feat(log): add Logger.Debugln, expand test coverage, update Go/CI

- Add missing Logger.Debugln method (package-level Debugln existed but
  Logger type lacked it)
- Replace empty test stubs with real tests for Debug, Debugf, Info,
  Infof, Print, Printf, Notice, Warn, Warnf, Error, Errorf, Panic,
  Panicf, Panicln
- Add tests for namespace filtering, multi-namespace clients,
  namespace registry, level storage, colorize, parseLevelString,
  Broadcast, matchesNamespace, fileInfo, Logger.Debugln,
  empty namespace default
- Update go.mod to Go 1.26.1
- Update CI to actions/checkout@v4, actions/setup-go@v5, Go 1.26,
  add -race flag, trigger on pull_request
- Fix stale CRUSH.md references (Go version, CI config, stderr bug)

.github/workflows/ci.yaml

@@ -1,23 +1,20 @@
 name: Go package
 
-on: [push]
+on: [push, pull_request]
 
 jobs:
   test:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
 
       - name: Set up Go
-        uses: actions/setup-go@v4
+        uses: actions/setup-go@v5
         with:
-          go-version: "1.21"
+          go-version: "1.26"
-
-      - name: Install dependencies
-        run: go get .
 
       - name: Build
         run: go build -v ./...
 
       - name: Test
-        run: go test -v ./...
+        run: go test -race -v ./...

CRUSH.md

@@ -0,0 +1,492 @@
+# CRUSH.md - Log Socket v2 Development Guide
+
+This document provides context and conventions for working on **log-socket v2** - a real-time log viewer with WebSocket support and namespace filtering, written in Go.
+
+## Project Overview
+
+Log Socket v2 is a Go library and standalone application that provides:
+- Real-time log streaming via WebSocket
+- **Namespace-based log organization** (NEW in v2)
+- Web-based log viewer with namespace filtering
+- Support for multiple log levels (TRACE, DEBUG, INFO, NOTICE, WARN, ERROR, PANIC, FATAL)
+- Client architecture allowing multiple subscribers to filtered log streams
+
+**Key insight**: This is both a library (importable Go package) and a standalone application. The main.go serves as an example implementation.
+
+## Essential Commands
+
+### Build
+```bash
+go build -v ./...
+```
+
+### Run Server
+```bash
+# Default (runs on 0.0.0.0:8080)
+go run main.go
+
+# Custom address
+go run main.go -addr localhost:8080
+```
+
+Once running, open browser to `http://localhost:8080` to view logs.
+
+### Test
+```bash
+go test -v ./...
+```
+
+### Install
+```bash
+go install github.com/taigrr/log-socket/v2@latest
+```
+
+### Dependencies
+```bash
+go get .
+```
+
+## Project Structure
+
+```
+.
+├── main.go              # Example server with multiple namespaces
+├── log/                 # Core logging package
+│   ├── log.go          # Package-level logging functions + namespace tracking
+│   ├── logger.go       # Logger type with namespace support
+│   ├── types.go        # Type definitions (includes Namespace fields)
+│   └── log_test.go     # Tests
+├── ws/                  # WebSocket server
+│   ├── server.go       # LogSocketHandler with namespace filtering
+│   └── namespaces.go   # HTTP handler for namespace list API
+└── browser/             # Web UI
+    ├── browser.go      # HTTP handler serving embedded HTML
+    └── viewer.html     # Embedded web interface with namespace filter
+```
+
+## Major Changes in v2
+
+### Module Path
+- **v1**: `github.com/taigrr/log-socket`
+- **v2**: `github.com/taigrr/log-socket/v2`
+
+### Namespace Support
+
+**Core concept**: Namespaces allow organizing logs by component, service, or domain (e.g., "api", "database", "auth").
+
+#### Types Changes
+
+**Entry** now includes:
+```go
+type Entry struct {
+    Timestamp time.Time `json:"timestamp"`
+    Output    string    `json:"output"`
+    File      string    `json:"file"`
+    Level     string    `json:"level"`
+    Namespace string    `json:"namespace"` // NEW
+    level     Level
+}
+```
+
+**Client** now uses a slice for filtering:
+```go
+type Client struct {
+    LogLevel    Level    `json:"level"`
+    Namespaces  []string `json:"namespaces"` // Empty = all namespaces
+    writer      LogWriter
+    initialized bool
+}
+```
+
+**Logger** has namespace field:
+```go
+type Logger struct {
+    FileInfoDepth int
+    Namespace     string // NEW
+}
+```
+
+#### API Changes
+
+**CreateClient** now variadic:
+```go
+// v1
+func CreateClient() *Client
+
+// v2
+func CreateClient(namespaces ...string) *Client
+
+// Examples:
+client := log.CreateClient()                    // All namespaces
+client := log.CreateClient("api")               // Single namespace
+client := log.CreateClient("api", "database")   // Multiple namespaces
+```
+
+**NewLogger** constructor added:
+```go
+func NewLogger(namespace string) *Logger
+
+// Example:
+apiLogger := log.NewLogger("api")
+apiLogger.Info("API request received")
+```
+
+### Namespace Tracking
+
+Global namespace registry tracks all used namespaces:
+```go
+var (
+    namespaces    map[string]bool
+    namespacesMux sync.RWMutex
+)
+
+func GetNamespaces() []string
+```
+
+Namespaces are automatically registered when logs are created.
+
+### WebSocket Changes
+
+**Query parameter for filtering**:
+```
+ws://localhost:8080/ws?namespaces=api,database
+```
+
+The handler parses comma-separated namespace list and creates a filtered client.
+
+### Web UI Changes
+
+- Namespace filter input field added to controls
+- Namespace column added to log table
+- Reconnect button to apply namespace filter
+- WebSocket URL includes namespace query parameter
+
+## Code Organization & Architecture
+
+### Log Package (`log/`)
+
+Dual API remains, but with namespace support:
+
+1. **Package-level functions**: Use "default" namespace
+   - `log.Info()`, `log.Debug()`, etc.
+   - All entry creations include `Namespace: DefaultNamespace`
+
+2. **Logger instances**: Use custom namespace
+   - Create with `log.NewLogger(namespace)`
+   - All entry creations include `Namespace: l.Namespace`
+
+### Client Architecture (Updated)
+
+**Client filtering by namespace**:
+
+1. **Empty Namespaces slice**: Receives all logs regardless of namespace
+2. **Non-empty Namespaces**: Only receives logs matching one of the specified namespaces
+
+**matchesNamespace helper**:
+```go
+func (c *Client) matchesNamespace(namespace string) bool {
+    // Empty Namespaces slice means match all
+    if len(c.Namespaces) == 0 {
+        return true
+    }
+    for _, ns := range c.Namespaces {
+        if ns == namespace {
+            return true
+        }
+    }
+    return false
+}
+```
+
+**Entry flow with namespace filtering**:
+1. Log function called with namespace
+2. `Entry` created with namespace field
+3. Namespace registered in global map
+4. `createLog()` sends to all clients
+5. Each client checks `matchesNamespace()`
+6. Only matching clients receive the entry
+
+### WebSocket Handler (`ws/`)
+
+**Namespace parameter parsing**:
+```go
+namespacesParam := r.URL.Query().Get("namespaces")
+var namespaces []string
+if namespacesParam != "" {
+    namespaces = strings.Split(namespacesParam, ",")
+}
+lc := logger.CreateClient(namespaces...)
+```
+
+**Namespaces API handler** (`ws/namespaces.go`):
+```go
+func NamespacesHandler(w http.ResponseWriter, r *http.Request) {
+    namespaces := logger.GetNamespaces()
+    w.Header().Set("Content-Type", "application/json")
+    json.NewEncoder(w).Encode(map[string]interface{}{
+        "namespaces": namespaces,
+    })
+}
+```
+
+### Browser Package (`browser/`)
+
+Still embeds viewer.html, but HTML now includes:
+- Namespace filter input
+- Namespace column in grid (5 columns instead of 4)
+- `reconnectWithNamespace()` method
+- WebSocket URL construction with query parameter
+
+## Go Version & Dependencies
+
+- **Go version**: 1.26.1 (specified in go.mod)
+- **Only external dependency**: `github.com/gorilla/websocket v1.5.3`
+
+## Naming Conventions & Style
+
+### Namespaces
+- Use lowercase strings: `"api"`, `"database"`, `"auth"`, `"cache"`
+- Default constant: `DefaultNamespace = "default"`
+- Comma-separated in query params: `?namespaces=api,database`
+
+### Log Levels
+Unchanged from v1 - still use uppercase strings and iota constants.
+
+### Variable Names
+- Use descriptive names (`apiLogger`, `dbLogger`, `namespaces`)
+- Exception: Loop variables, short-lived scopes
+
+## Important Patterns & Gotchas
+
+### 1. Namespace Tracking is Automatic
+When any log is created, its namespace is automatically added to the global registry:
+```go
+func createLog(e Entry) {
+    // Track namespace
+    namespacesMux.Lock()
+    namespaces[e.Namespace] = true
+    namespacesMux.Unlock()
+    // ... rest of function
+}
+```
+
+**No manual registration needed** - just log and the namespace appears.
+
+### 2. Empty Namespace List = All Logs
+Both for clients and WebSocket connections:
+```go
+client := log.CreateClient()           // Gets ALL logs
+ws://localhost:8080/ws                 // Gets ALL logs
+```
+
+This is the default behavior to maintain backward compatibility.
+
+### 3. Client Namespace Filtering is Inclusive (OR)
+If a client has multiple namespaces, it receives logs matching ANY of them:
+```go
+client := log.CreateClient("api", "database")
+// Receives logs from "api" OR "database", not "auth"
+```
+
+### 4. Namespace Field Always Set
+All logging functions set namespace:
+- Package functions: `DefaultNamespace`
+- Logger methods: `l.Namespace`
+
+**Never nil or empty** - there's always a namespace.
+
+### 5. WebSocket Namespace Reconnection
+Changing namespace filter requires reconnecting WebSocket:
+```javascript
+reconnectWithNamespace() {
+    if (this.ws) {
+        this.ws.onclose = null; // Prevent auto-reconnect
+        this.ws.close();
+        this.ws = null;
+    }
+    this.reconnectAttempts = 0;
+    this.connectWebSocket(); // Creates new connection with new filter
+}
+```
+
+UI provides "Reconnect" button for this purpose.
+
+### 6. Stderr Client Uses All Namespaces
+The built-in stderr client (created in `init()`) listens to all namespaces:
+```go
+stderrClient = CreateClient() // No args = all namespaces
+```
+
+It prints logs matching its level and namespace filter in `logStdErr()`:
+```go
+if e.level >= c.LogLevel && c.matchesNamespace(e.Namespace) {
+    fmt.Fprintf(os.Stderr, "%s\t%s\t[%s]\t%s\t%s\n", ...)
+}
+```
+
+Since `CreateClient()` is called with no arguments, the Namespaces slice is empty, which means it matches all namespaces.
+
+### 7. Grid Layout Updated
+The log viewer grid changed from 4 to 5 columns:
+```css
+/* v1 */
+grid-template-columns: 180px 80px 1fr 120px;
+
+/* v2 */
+grid-template-columns: 180px 80px 100px 1fr 120px;
+```
+
+Order: Timestamp, Level, Namespace, Message, Source
+
+## Testing
+
+### Test Updates for v2
+
+All `CreateClient()` calls in tests now pass namespace:
+```go
+// v1
+c := CreateClient()
+
+// v2
+c := CreateClient("test")
+c := CreateClient(DefaultNamespace)
+```
+
+Tests verify namespace appears in output (see stderr format).
+
+### Running Tests
+```bash
+go test -v ./...
+```
+
+All existing tests pass with namespace support added.
+
+## CI/CD
+
+GitHub Actions workflow (`.github/workflows/ci.yaml`):
+- Uses Go 1.26, actions/checkout@v4, actions/setup-go@v5
+- Runs tests with `-race` flag
+- Triggers on push and pull_request
+
+## Common Tasks
+
+### Adding a New Namespace
+
+No code changes needed! Just create a logger:
+```go
+cacheLogger := log.NewLogger("cache")
+cacheLogger.Info("Cache initialized")
+```
+
+Namespace automatically tracked and available via API.
+
+### Creating Namespace-Specific Client
+
+```go
+// Subscribe only to API logs
+apiClient := log.CreateClient("api")
+defer apiClient.Destroy()
+
+for {
+    entry := apiClient.Get()
+    // Only receives logs from "api" namespace
+    processAPILog(entry)
+}
+```
+
+### Filtering WebSocket by Namespace
+
+Frontend:
+```javascript
+// Set namespace filter
+document.getElementById('namespaceFilter').value = 'api,database';
+// Click reconnect button or call:
+logViewer.reconnectWithNamespace();
+```
+
+Backend automatically creates filtered client based on query param.
+
+### Getting All Active Namespaces
+
+```go
+namespaces := log.GetNamespaces()
+// Returns: ["default", "api", "database", "auth", ...]
+```
+
+Or via HTTP:
+```bash
+GET /api/namespaces
+```
+
+Returns:
+```json
+{
+  "namespaces": ["default", "api", "database", "auth"]
+}
+```
+
+## Migration from v1 to v2
+
+### Import Paths
+```go
+// v1
+import "github.com/taigrr/log-socket/log"
+import "github.com/taigrr/log-socket/ws"
+import "github.com/taigrr/log-socket/browser"
+
+// v2
+import "github.com/taigrr/log-socket/v2/log"
+import "github.com/taigrr/log-socket/v2/ws"
+import "github.com/taigrr/log-socket/v2/browser"
+```
+
+### CreateClient Calls
+```go
+// v1
+client := log.CreateClient()
+
+// v2 - same behavior
+client := log.CreateClient() // Empty = all namespaces
+
+// v2 - new filtering capability
+client := log.CreateClient("api")
+client := log.CreateClient("api", "database")
+```
+
+### Default() Logger
+```go
+// v1
+logger := log.Default()
+
+// v2 - uses default namespace
+logger := log.Default()
+
+// v2 - new namespaced option
+logger := log.NewLogger("api")
+```
+
+### WebSocket URL
+```
+v1: ws://host/ws
+v2: ws://host/ws                          # All namespaces (backward compatible)
+v2: ws://host/ws?namespaces=api           # Filtered
+v2: ws://host/ws?namespaces=api,database  # Multiple
+```
+
+## Repository Context
+
+- **License**: Check LICENSE file
+- **Funding**: GitHub sponsors (.github/FUNDING.yml)
+- **Open Source**: github.com/taigrr/log-socket
+- **Version**: v2.x.x (major version bump for breaking changes)
+
+## Future Agent Notes
+
+- **v2 is a breaking change**: Major version bump follows Go modules convention
+- Namespace support is the primary new feature
+- Backward compatible behavior: empty namespace list = all logs
+- Namespace tracking is automatic via global registry
+- Web UI has been significantly updated for namespace support
+- Possible bug: stderr client might need to use `CreateClient()` instead of `CreateClient(DefaultNamespace)` to see all logs
+- All tests updated and passing
+- Example in main.go demonstrates multiple namespaces

README.md

@@ -1,11 +1,27 @@
-# Log Socket
+# Log Socket v2
 
-A real-time log viewer with WebSocket support, written in Go. This tool provides a web-based interface for viewing and filtering logs in real-time.
+A real-time log viewer with WebSocket support and namespace filtering, written in Go.
+
+## What's New in v2
+
+**Breaking Changes:**
+- Module path changed to `github.com/taigrr/log-socket/v2`
+- `CreateClient()` now accepts variadic `namespaces ...string` parameter
+- `Logger` type now includes `Namespace` field
+- New `NewLogger(namespace string)` constructor for namespaced loggers
+
+**New Features:**
+- **Namespace support**: Organize logs by namespace (api, database, auth, etc.)
+- **Namespace filtering**: Subscribe to specific namespaces via WebSocket
+- **Frontend namespace selector**: Filter logs by namespace in the web UI
+- **Namespace API**: GET `/api/namespaces` to list all active namespaces
+- **Colored terminal output**: Log levels are color-coded in terminal (no external packages)
 
 ## Features
 
 - Real-time log streaming via WebSocket
 - Web-based log viewer with filtering capabilities
+- **Namespace-based log organization**
 - Support for multiple log levels (TRACE, DEBUG, INFO, WARN, ERROR, PANIC, FATAL)
 - Color-coded log levels for better visibility
 - Auto-scrolling with toggle option
@@ -16,47 +32,228 @@ A real-time log viewer with WebSocket support, written in Go. This tool provides
 ## Installation
 
 ```bash
-go install github.com/taigrr/log-socket@latest
+go install github.com/taigrr/log-socket/v2@latest
 ```
 
-## Example Preview
+## Quick Start
 
-1. Start the server:
+```go
+package main
 
-   ```bash
+import (
-   log-socket
+	"net/http"
-   ```
+	logger "github.com/taigrr/log-socket/v2/log"
+	"github.com/taigrr/log-socket/v2/ws"
+	"github.com/taigrr/log-socket/v2/browser"
+)
 
-   By default, the server runs on `0.0.0.0:8080`. You can specify a different address using the `-addr` flag:
+func main() {
+	defer logger.Flush()
+	
+	// Set up HTTP handlers
+	http.HandleFunc("/ws", ws.LogSocketHandler)
+	http.HandleFunc("/api/namespaces", ws.NamespacesHandler)
+	http.HandleFunc("/", browser.LogSocketViewHandler)
+	
+	// Use default namespace
+	logger.Info("Application started")
+	
+	// Create namespaced loggers
+	apiLogger := logger.NewLogger("api")
+	dbLogger := logger.NewLogger("database")
+	
+	apiLogger.Info("API server ready")
+	dbLogger.Debug("Database connected")
+	
+	logger.Fatal(http.ListenAndServe(":8080", nil))
+}
+```
 
-   ```bash
+## Usage
-   log-socket -addr localhost:8080
-   ```
 
-2. Open your browser and navigate to `http://localhost:8080`
+### Starting the Server
 
-   ![Log Socket Web Interface](browser/screenshot.png)
+```bash
+log-socket
+```
 
-## Logging Interface
+By default, the server runs on `0.0.0.0:8080`. Specify a different address:
 
-The package provides a comprehensive logging interface with the following methods:
+```bash
+log-socket -addr localhost:8080
+```
 
-- `Trace/Tracef/Traceln`: For trace-level logging
+### Web Interface
-- `Debug/Debugf/Debugln`: For debug-level logging
+
-- `Info/Infof/Infoln`: For info-level logging
+Open your browser and navigate to `http://localhost:8080`
-- `Notice/Noticef/Noticeln`: For notice-level logging
+
-- `Warn/Warnf/Warnln`: For warning-level logging
+**Namespace Filtering:**
-- `Error/Errorf/Errorln`: For error-level logging
+- The namespace dropdown is automatically populated from `/api/namespaces`
-- `Panic/Panicf/Panicln`: For panic-level logging
+- Select one or more namespaces to filter (hold Ctrl/Cmd to multi-select)
-- `Fatal/Fatalf/Fatalln`: For fatal-level logging
+- Default is "All Namespaces" (shows everything)
+- Click "Reconnect" to apply the filter
+
+## API
+
+### Logging Interface
+
+The package provides two ways to log:
+
+#### 1. Package-level functions (default namespace)
+
+```go
+logger.Trace("trace message")
+logger.Debug("debug message")
+logger.Info("info message")
+logger.Notice("notice message")
+logger.Warn("warning message")
+logger.Error("error message")
+logger.Panic("panic message")  // Logs and panics
+logger.Fatal("fatal message")  // Logs and exits
+```
+
+Each has formatted (`f`) and line (`ln`) variants:
+```go
+logger.Infof("User %s logged in", username)
+logger.Infoln("This adds a newline")
+```
+
+#### 2. Namespaced loggers
+
+```go
+apiLogger := logger.NewLogger("api")
+apiLogger.Info("Request received")
+
+dbLogger := logger.NewLogger("database")  
+dbLogger.Warn("Slow query detected")
+```
+
+### Creating Clients with Namespace Filters
+
+```go
+// Listen to all namespaces
+client := logger.CreateClient()
+
+// Listen to specific namespace
+client := logger.CreateClient("api")
+
+// Listen to multiple namespaces
+client := logger.CreateClient("api", "database", "auth")
+```
+
+### WebSocket API
+
+#### Log Stream Endpoint
+
+**URL:** `ws://localhost:8080/ws`
+
+**Query Parameters:**
+- `namespaces` (optional): Comma-separated list of namespaces to filter
+
+**Examples:**
+```
+ws://localhost:8080/ws                     # All namespaces
+ws://localhost:8080/ws?namespaces=api      # Only "api" namespace
+ws://localhost:8080/ws?namespaces=api,database  # Multiple namespaces
+```
+
+**Message Format:**
+```json
+{
+  "timestamp": "2024-11-10T15:42:49.777298-05:00",
+  "output": "API request received",
+  "file": "main.go:42",
+  "level": "INFO",
+  "namespace": "api"
+}
+```
+
+#### Namespaces List Endpoint
+
+**URL:** `GET http://localhost:8080/api/namespaces`
+
+**Response:**
+```json
+{
+  "namespaces": ["default", "api", "database", "auth"]
+}
+```
 
 ## Web Interface Features
 
-- **Filtering**: Type in the search box to filter logs
+- **Namespace Dropdown**: Dynamically populated from `/api/namespaces`, multi-select support
-- **Auto-scroll**: Toggle auto-scrolling with the checkbox
+- **Text Search**: Filter logs by content, level, namespace, or source file
+- **Auto-scroll**: Toggle auto-scrolling with checkbox
 - **Download**: Save all logs as a JSON file
 - **Clear**: Remove all logs from the viewer
-- **Color Coding**: Different log levels are color-coded for easy identification
+- **Color Coding**: Different log levels are color-coded
+- **Reconnect**: Reconnect WebSocket with new namespace filter
+
+## Terminal Colors
+
+Log output to stderr is automatically colorized when writing to a terminal. Colors are disabled when output is piped or redirected to a file.
+
+### Color Scheme
+
+| Level  | Color        |
+|--------|--------------|
+| TRACE  | Gray         |
+| DEBUG  | Cyan         |
+| INFO   | Green        |
+| NOTICE | Blue         |
+| WARN   | Yellow       |
+| ERROR  | Red          |
+| PANIC  | Bold Red     |
+| FATAL  | Bold Red     |
+
+### Controlling Colors
+
+```go
+// Disable colors (e.g., for CI/CD or file output)
+logger.SetColorEnabled(false)
+
+// Enable colors explicitly
+logger.SetColorEnabled(true)
+
+// Check current state
+if logger.ColorEnabled() {
+    // colors are on
+}
+```
+
+Colors are implemented using standard ANSI escape codes with no external dependencies.
+
+## Migration from v1
+
+### Import Path
+
+```go
+// v1
+import "github.com/taigrr/log-socket/log"
+
+// v2
+import "github.com/taigrr/log-socket/v2/log"
+```
+
+### CreateClient Changes
+
+```go
+// v1
+client := log.CreateClient()
+
+// v2 - specify namespace(s) or leave empty for all
+client := log.CreateClient()              // All namespaces
+client := log.CreateClient("api")         // Single namespace
+client := log.CreateClient("api", "db")   // Multiple namespaces
+```
+
+### New Logger Constructor
+
+```go
+// v2 only - create namespaced logger
+apiLogger := log.NewLogger("api")
+apiLogger.Info("Message in api namespace")
+```
 
 ## Dependencies
 
@@ -64,6 +261,8 @@ The package provides a comprehensive logging interface with the following method
 
 ## Notes
 
-The web interface is not meant to be used as-is.
+The web interface is provided as an example implementation. Users are encouraged to customize it for their specific needs. The WebSocket endpoint (`/ws`) can be consumed by any WebSocket client.
-It functions perfectly well for some scenarios, but it is broken out into a different package intentionally, such that users can add their own as they see fit.
+
-It's mostly here to provide an example of how to consume the websocket data and display it.
+## License
+
+See LICENSE file for details.

browser/viewer.html

@@ -126,7 +126,7 @@
 
 		.log-row {
 			display: grid;
-			grid-template-columns: 180px 80px 1fr 120px;
+			grid-template-columns: 180px 80px 100px 1fr 120px;
 			gap: 15px;
 			padding: 10px 15px;
 			border-bottom: 1px solid var(--border-color);
@@ -321,6 +321,17 @@
 		<header class="header">
 			<h1>📊 Log Viewer</h1>
 			<div class="controls">
+				<div class="search-container">
+					<select 
+						id="namespaceFilter" 
+						class="search-input"
+						multiple
+						size="1"
+						aria-label="Filter by namespace"
+					>
+						<option value="">All Namespaces (loading...)</option>
+					</select>
+				</div>
 				<div class="search-container">
 					<input 
 						type="text" 
@@ -334,6 +345,9 @@
 					<input type="checkbox" id="shouldScroll" checked>
 					<label for="shouldScroll">Auto-scroll</label>
 				</div>
+				<button id="reconnectBtn" class="btn btn-primary">
+					🔄 Reconnect
+				</button>
 			</div>
 		</header>
 
@@ -342,6 +356,7 @@
 				<div class="log-row">
 					<div class="log-cell">Timestamp</div>
 					<div class="log-cell">Level</div>
+					<div class="log-cell">Namespace</div>
 					<div class="log-cell">Message</div>
 					<div class="log-cell">Source</div>
 				</div>
@@ -385,6 +400,7 @@
 				
 				this.initializeElements();
 				this.attachEventListeners();
+				this.fetchNamespaces();
 				this.connectWebSocket();
 				this.startAutoScroll();
 			}
@@ -392,10 +408,12 @@
 			initializeElements() {
 				this.logViewer = document.getElementById('logViewer');
 				this.emptyState = document.getElementById('emptyState');
+				this.namespaceFilter = document.getElementById('namespaceFilter');
 				this.searchInput = document.getElementById('search');
 				this.scrollCheckbox = document.getElementById('shouldScroll');
 				this.downloadBtn = document.getElementById('downloadBtn');
 				this.clearBtn = document.getElementById('clearBtn');
+				this.reconnectBtn = document.getElementById('reconnectBtn');
 				this.statusIndicator = document.getElementById('statusIndicator');
 				this.connectionStatus = document.getElementById('connectionStatus');
 				this.logCount = document.getElementById('logCount');
@@ -403,15 +421,61 @@
 
 			attachEventListeners() {
 				this.searchInput.addEventListener('input', this.debounce(() => this.filterLogs(), 300));
+				this.namespaceFilter.addEventListener('change', () => this.reconnectWithNamespace());
 				this.downloadBtn.addEventListener('click', () => this.downloadLogs());
 				this.clearBtn.addEventListener('click', () => this.clearLogs());
+				this.reconnectBtn.addEventListener('click', () => this.reconnectWithNamespace());
+			}
+
+			async fetchNamespaces() {
+				try {
+					const response = await fetch('/api/namespaces');
+					const data = await response.json();
+					this.updateNamespaceFilter(data.namespaces || []);
+				} catch (error) {
+					console.error('Failed to fetch namespaces:', error);
+				}
+			}
+
+			updateNamespaceFilter(namespaces) {
+				// Clear existing options
+				this.namespaceFilter.innerHTML = '';
+				
+				// Add "All" option
+				const allOption = document.createElement('option');
+				allOption.value = '';
+				allOption.textContent = 'All Namespaces';
+				allOption.selected = true;
+				this.namespaceFilter.appendChild(allOption);
+				
+				// Add namespace options
+				namespaces.sort().forEach(ns => {
+					const option = document.createElement('option');
+					option.value = ns;
+					option.textContent = ns;
+					this.namespaceFilter.appendChild(option);
+				});
 			}
 
 			connectWebSocket() {
 				if (this.ws) return;
 
 				try {
-					this.ws = new WebSocket("{{.}}");
+					let wsUrl = "{{.}}";
+					
+					// Get selected namespace options from multi-select
+					const selectedOptions = Array.from(this.namespaceFilter.selectedOptions)
+						.map(opt => opt.value)
+						.filter(val => val !== ''); // Remove empty "All" option
+					
+					// Add namespace filter if specific namespaces selected
+					if (selectedOptions.length > 0) {
+						const namespaces = selectedOptions.join(',');
+						const separator = wsUrl.includes('?') ? '&' : '?';
+						wsUrl += `${separator}namespaces=${encodeURIComponent(namespaces)}`;
+					}
+					
+					this.ws = new WebSocket(wsUrl);
 					this.updateConnectionStatus('Connecting...', false);
 
 					this.ws.onopen = () => {
@@ -448,6 +512,16 @@
 				}
 			}
 
+			reconnectWithNamespace() {
+				if (this.ws) {
+					this.ws.onclose = null; // Prevent auto-reconnect
+					this.ws.close();
+					this.ws = null;
+				}
+				this.reconnectAttempts = 0;
+				this.connectWebSocket();
+			}
+
 			scheduleReconnect() {
 				if (this.reconnectAttempts < this.maxReconnectAttempts) {
 					this.reconnectAttempts++;
@@ -480,6 +554,7 @@
 				logRow.innerHTML = `
 					<div class="log-cell timestamp">${this.formatTimestamp(entry.timestamp)}</div>
 					<div class="log-cell level">${entry.level}</div>
+					<div class="log-cell namespace">${this.escapeHtml(entry.namespace || 'default')}</div>
 					<div class="log-cell output">${this.escapeHtml(entry.output)}</div>
 					<div class="log-cell source">${this.escapeHtml(entry.file || 'N/A')}</div>
 				`;
@@ -536,6 +611,7 @@
 				return (
 					entry.output.toLowerCase().includes(query) ||
 					entry.level.toLowerCase().includes(query) ||
+					(entry.namespace && entry.namespace.toLowerCase().includes(query)) ||
 					(entry.file && entry.file.toLowerCase().includes(query)) ||
 					entry.timestamp.toLowerCase().includes(query)
 				);

examples/basic/main.go

@@ -0,0 +1,36 @@
+// Example: basic usage of log-socket as a drop-in logger.
+//
+// This demonstrates using the package-level logging functions,
+// which work similarly to the standard library's log package.
+package main
+
+import (
+	"fmt"
+	"net/http"
+
+	"github.com/taigrr/log-socket/v2/browser"
+	logger "github.com/taigrr/log-socket/v2/log"
+	"github.com/taigrr/log-socket/v2/ws"
+)
+
+func main() {
+	defer logger.Flush()
+
+	// Set the minimum log level (default is LTrace, showing everything)
+	logger.SetLogLevel(logger.LDebug)
+
+	// Package-level functions log to the "default" namespace
+	logger.Info("Application starting up")
+	logger.Debug("Debug mode enabled")
+	logger.Warnf("Config file not found at %s, using defaults", "/etc/app/config.yaml")
+	logger.Errorf("Failed to connect to database: %s", "connection refused")
+
+	// Print/Printf/Println are aliases for Info
+	logger.Println("This is equivalent to Infoln")
+
+	// Start the web UI so you can view logs at http://localhost:8080
+	http.HandleFunc("/ws", ws.LogSocketHandler)
+	http.HandleFunc("/", browser.LogSocketViewHandler)
+	fmt.Println("Log viewer available at http://localhost:8080")
+	logger.Fatal(http.ListenAndServe("0.0.0.0:8080", nil))
+}

examples/client/main.go

@@ -0,0 +1,63 @@
+// Example: programmatic log client with namespace filtering.
+//
+// This shows how to create a Client that receives log entries
+// programmatically, optionally filtered to specific namespaces.
+// Useful for building custom log processors, alerting, or forwarding.
+package main
+
+import (
+	"fmt"
+	"time"
+
+	logger "github.com/taigrr/log-socket/v2/log"
+)
+
+func main() {
+	defer logger.Flush()
+
+	// Create a client that receives ALL log entries
+	allLogs := logger.CreateClient()
+	allLogs.SetLogLevel(logger.LInfo)
+
+	// Create a client that only receives "database" and "auth" logs
+	securityLogs := logger.CreateClient("database", "auth")
+	securityLogs.SetLogLevel(logger.LWarn) // Only warnings and above
+
+	dbLog := logger.NewLogger("database")
+	authLog := logger.NewLogger("auth")
+	apiLog := logger.NewLogger("api")
+
+	// Process all logs
+	go func() {
+		for {
+			entry := allLogs.Get()
+			fmt.Printf("[ALL] %s [%s] %s: %s\n",
+				entry.Timestamp.Format(time.TimeOnly),
+				entry.Namespace, entry.Level, entry.Output)
+		}
+	}()
+
+	// Process only security-relevant warnings/errors
+	go func() {
+		for {
+			entry := securityLogs.Get()
+			if entry.Level == "ERROR" || entry.Level == "WARN" {
+				fmt.Printf("🚨 SECURITY ALERT [%s] %s: %s\n",
+					entry.Namespace, entry.Level, entry.Output)
+			}
+		}
+	}()
+
+	// Generate some logs
+	for i := 0; i < 5; i++ {
+		apiLog.Info("API request processed")
+		dbLog.Info("Query executed successfully")
+		dbLog.Warn("Connection pool running low")
+		authLog.Error("Brute force attempt detected")
+		time.Sleep(1 * time.Second)
+	}
+
+	// Clean up clients when done
+	allLogs.Destroy()
+	securityLogs.Destroy()
+}

examples/log-levels/main.go

@@ -0,0 +1,48 @@
+// Example: log level filtering and all available levels.
+//
+// log-socket supports 8 log levels from TRACE (most verbose)
+// to FATAL (least verbose). Setting a log level filters out
+// everything below it.
+package main
+
+import (
+	"fmt"
+
+	logger "github.com/taigrr/log-socket/v2/log"
+)
+
+func main() {
+	defer logger.Flush()
+
+	fmt.Println("=== All log levels (TRACE and above) ===")
+	logger.SetLogLevel(logger.LTrace)
+
+	logger.Trace("Detailed execution trace — variable x = 42")
+	logger.Debug("Processing request for user_id=123")
+	logger.Info("Server started on :8080")
+	logger.Notice("Configuration reloaded")
+	logger.Warn("Disk usage at 85%")
+	logger.Error("Failed to send email: SMTP timeout")
+	// logger.Panic("...") — would panic
+	// logger.Fatal("...") — would os.Exit(1)
+
+	fmt.Println("\n=== Formatted variants ===")
+	logger.Infof("Request took %dms", 42)
+	logger.Warnf("Retrying in %d seconds (attempt %d/%d)", 5, 2, 3)
+	logger.Errorf("HTTP %d: %s", 503, "Service Unavailable")
+
+	fmt.Println("\n=== Only WARN and above ===")
+	logger.SetLogLevel(logger.LWarn)
+
+	logger.Debug("This will NOT appear")
+	logger.Info("This will NOT appear either")
+	logger.Warn("This WILL appear")
+	logger.Error("This WILL appear too")
+
+	fmt.Println("\n=== Per-logger levels via namespaced loggers ===")
+	logger.SetLogLevel(logger.LTrace) // Reset global
+
+	appLog := logger.NewLogger("app")
+	appLog.Info("Namespaced loggers inherit the global output but tag entries")
+	appLog.Warnf("Something needs attention in the %s subsystem", "app")
+}

examples/namespaces/main.go

@@ -0,0 +1,73 @@
+// Example: namespace-based logging for organizing logs by component.
+//
+// Namespaces let you tag log entries by subsystem (api, database, auth, etc.)
+// and filter them in the web UI or via programmatic clients.
+package main
+
+import (
+	"fmt"
+	"math/rand"
+	"net/http"
+	"time"
+
+	"github.com/taigrr/log-socket/v2/browser"
+	logger "github.com/taigrr/log-socket/v2/log"
+	"github.com/taigrr/log-socket/v2/ws"
+)
+
+func main() {
+	defer logger.Flush()
+
+	// Create loggers for different subsystems
+	apiLog := logger.NewLogger("api")
+	dbLog := logger.NewLogger("database")
+	authLog := logger.NewLogger("auth")
+	cacheLog := logger.NewLogger("cache")
+
+	// Simulate application activity
+	go func() {
+		for {
+			apiLog.Infof("GET /api/users — 200 OK (%dms)", rand.Intn(200))
+			apiLog.Debugf("Request headers: Accept=application/json")
+			time.Sleep(1 * time.Second)
+		}
+	}()
+
+	go func() {
+		for {
+			dbLog.Infof("SELECT * FROM users — %d rows", rand.Intn(100))
+			if rand.Float64() < 0.3 {
+				dbLog.Warn("Slow query detected (>500ms)")
+			}
+			time.Sleep(2 * time.Second)
+		}
+	}()
+
+	go func() {
+		for {
+			if rand.Float64() < 0.7 {
+				authLog.Info("User login successful")
+			} else {
+				authLog.Error("Failed login attempt from 192.168.1.42")
+			}
+			time.Sleep(3 * time.Second)
+		}
+	}()
+
+	go func() {
+		for {
+			cacheLog.Tracef("Cache hit ratio: %.1f%%", rand.Float64()*100)
+			if rand.Float64() < 0.1 {
+				cacheLog.Warn("Cache eviction triggered")
+			}
+			time.Sleep(5 * time.Second)
+		}
+	}()
+
+	// The /api/namespaces endpoint lists all active namespaces
+	http.HandleFunc("/ws", ws.LogSocketHandler)
+	http.HandleFunc("/api/namespaces", ws.NamespacesHandler)
+	http.HandleFunc("/", browser.LogSocketViewHandler)
+	fmt.Println("Log viewer with namespace filtering at http://localhost:8080")
+	logger.Fatal(http.ListenAndServe("0.0.0.0:8080", nil))
+}

go.mod

@@ -1,5 +1,5 @@
-module github.com/taigrr/log-socket
+module github.com/taigrr/log-socket/v2
 
-go 1.24.4
+go 1.26.1
 
 require github.com/gorilla/websocket v1.5.3

log/bench_test.go

@@ -0,0 +1,171 @@
+package log
+
+import (
+	"fmt"
+	"testing"
+)
+
+const benchNS = "bench-isolated-ns"
+
+// benchClient creates a client with a continuous drain goroutine.
+// Returns the client and a stop function to call after b.StopTimer().
+func benchClient(ns string) (*Client, func()) {
+	c := CreateClient(ns)
+	c.SetLogLevel(LTrace)
+	done := make(chan struct{})
+	go func() {
+		for {
+			select {
+			case <-done:
+				return
+			case <-c.writer:
+			}
+		}
+	}()
+	return c, func() {
+		close(done)
+		c.Destroy()
+	}
+}
+
+// BenchmarkCreateClient measures client creation overhead.
+func BenchmarkCreateClient(b *testing.B) {
+	for i := 0; i < b.N; i++ {
+		c := CreateClient("bench")
+		c.Destroy()
+	}
+}
+
+// BenchmarkTrace benchmarks Logger.Trace.
+func BenchmarkTrace(b *testing.B) {
+	l := NewLogger(benchNS)
+	_, stop := benchClient(benchNS)
+	defer stop()
+	b.ResetTimer()
+	for i := 0; i < b.N; i++ {
+		l.Trace("benchmark trace message")
+	}
+}
+
+// BenchmarkTracef benchmarks formatted Logger.Tracef.
+func BenchmarkTracef(b *testing.B) {
+	l := NewLogger(benchNS)
+	_, stop := benchClient(benchNS)
+	defer stop()
+	b.ResetTimer()
+	for i := 0; i < b.N; i++ {
+		l.Tracef("benchmark trace message %d", i)
+	}
+}
+
+// BenchmarkDebug benchmarks Logger.Debug.
+func BenchmarkDebug(b *testing.B) {
+	l := NewLogger(benchNS)
+	_, stop := benchClient(benchNS)
+	defer stop()
+	b.ResetTimer()
+	for i := 0; i < b.N; i++ {
+		l.Debug("benchmark debug message")
+	}
+}
+
+// BenchmarkInfo benchmarks Logger.Info.
+func BenchmarkInfo(b *testing.B) {
+	l := NewLogger(benchNS)
+	_, stop := benchClient(benchNS)
+	defer stop()
+	b.ResetTimer()
+	for i := 0; i < b.N; i++ {
+		l.Info("benchmark info message")
+	}
+}
+
+// BenchmarkInfof benchmarks Logger.Infof with formatting.
+func BenchmarkInfof(b *testing.B) {
+	l := NewLogger(benchNS)
+	_, stop := benchClient(benchNS)
+	defer stop()
+	b.ResetTimer()
+	for i := 0; i < b.N; i++ {
+		l.Infof("user %s performed action %d", "testuser", i)
+	}
+}
+
+// BenchmarkWarn benchmarks Logger.Warn.
+func BenchmarkWarn(b *testing.B) {
+	l := NewLogger(benchNS)
+	_, stop := benchClient(benchNS)
+	defer stop()
+	b.ResetTimer()
+	for i := 0; i < b.N; i++ {
+		l.Warn("benchmark warn message")
+	}
+}
+
+// BenchmarkError benchmarks Logger.Error.
+func BenchmarkError(b *testing.B) {
+	l := NewLogger(benchNS)
+	_, stop := benchClient(benchNS)
+	defer stop()
+	b.ResetTimer()
+	for i := 0; i < b.N; i++ {
+		l.Error("benchmark error message")
+	}
+}
+
+// BenchmarkMultipleClients measures fan-out to multiple consumers.
+func BenchmarkMultipleClients(b *testing.B) {
+	const numClients = 5
+	l := NewLogger(benchNS)
+	stops := make([]func(), numClients)
+	for i := range stops {
+		_, stops[i] = benchClient(benchNS)
+	}
+	b.ResetTimer()
+	for i := 0; i < b.N; i++ {
+		l.Info("benchmark multi-client")
+	}
+	b.StopTimer()
+	for _, stop := range stops {
+		stop()
+	}
+}
+
+// BenchmarkParallelInfo benchmarks concurrent Info calls from multiple goroutines.
+func BenchmarkParallelInfo(b *testing.B) {
+	l := NewLogger(benchNS)
+	_, stop := benchClient(benchNS)
+	defer stop()
+	b.ResetTimer()
+	b.RunParallel(func(pb *testing.PB) {
+		for pb.Next() {
+			l.Info("parallel benchmark info")
+		}
+	})
+}
+
+// BenchmarkNamespaceFiltering benchmarks logging when the consumer
+// filters by a different namespace (messages are not delivered).
+func BenchmarkNamespaceFiltering(b *testing.B) {
+	l := NewLogger(benchNS)
+	_, stop := benchClient("completely-different-ns")
+	defer stop()
+	b.ResetTimer()
+	for i := 0; i < b.N; i++ {
+		l.Info("filtered out message")
+	}
+}
+
+// BenchmarkFileInfo measures the cost of runtime.Caller for file info.
+func BenchmarkFileInfo(b *testing.B) {
+	for i := 0; i < b.N; i++ {
+		fileInfo(1)
+	}
+}
+
+// BenchmarkEntryCreation measures raw fmt.Sprint overhead (baseline).
+func BenchmarkEntryCreation(b *testing.B) {
+	for i := 0; i < b.N; i++ {
+		_ = fmt.Sprint("benchmark message ", i)
+	}
+}

log/color.go

@@ -0,0 +1,99 @@
+package log
+
+import (
+	"os"
+	"sync"
+)
+
+// ANSI color codes for terminal output
+const (
+	colorReset  = "\033[0m"
+	colorRed    = "\033[31m"
+	colorGreen  = "\033[32m"
+	colorYellow = "\033[33m"
+	colorBlue   = "\033[34m"
+	colorPurple = "\033[35m"
+	colorCyan   = "\033[36m"
+	colorWhite  = "\033[37m"
+	colorGray   = "\033[90m"
+
+	// Bold variants
+	colorBoldRed    = "\033[1;31m"
+	colorBoldYellow = "\033[1;33m"
+	colorBoldWhite  = "\033[1;37m"
+)
+
+var (
+	colorEnabled     = true
+	colorEnabledOnce sync.Once
+	colorMux         sync.RWMutex
+)
+
+// SetColorEnabled enables or disables colored output for stderr logging.
+// By default, color is enabled when stderr is a terminal.
+func SetColorEnabled(enabled bool) {
+	colorMux.Lock()
+	colorEnabled = enabled
+	colorMux.Unlock()
+}
+
+// ColorEnabled returns whether colored output is currently enabled.
+func ColorEnabled() bool {
+	colorMux.RLock()
+	defer colorMux.RUnlock()
+	return colorEnabled
+}
+
+// isTerminal checks if the given file descriptor is a terminal.
+// This is a simple heuristic that works on Unix-like systems.
+func isTerminal(f *os.File) bool {
+	stat, err := f.Stat()
+	if err != nil {
+		return false
+	}
+	return (stat.Mode() & os.ModeCharDevice) != 0
+}
+
+// initColorEnabled sets the default color state based on whether stderr is a terminal.
+func initColorEnabled() {
+	colorEnabledOnce.Do(func() {
+		colorEnabled = isTerminal(os.Stderr)
+	})
+}
+
+// levelColor returns the ANSI color code for a given log level.
+func levelColor(level Level) string {
+	switch level {
+	case LTrace:
+		return colorGray
+	case LDebug:
+		return colorCyan
+	case LInfo:
+		return colorGreen
+	case LNotice:
+		return colorBlue
+	case LWarn:
+		return colorYellow
+	case LError:
+		return colorRed
+	case LPanic:
+		return colorBoldRed
+	case LFatal:
+		return colorBoldRed
+	default:
+		return colorReset
+	}
+}
+
+// colorize wraps text with ANSI color codes if color is enabled.
+func colorize(text string, color string) string {
+	if !ColorEnabled() {
+		return text
+	}
+	return color + text + colorReset
+}
+
+// colorizeLevelText returns the level string with appropriate color.
+func colorizeLevelText(level string, lvl Level) string {
+	return colorize(level, levelColor(lvl))
+}

log/log.go

@@ -16,9 +16,13 @@ var (
 	stderrClient   *Client
 	cleanup        sync.Once
 	stderrFinished chan bool
+	namespaces     map[string]bool
+	namespacesMux  sync.RWMutex
 )
 
 func init() {
+	namespaces = make(map[string]bool)
+	initColorEnabled()
 	stderrClient = CreateClient()
 	stderrClient.SetLogLevel(LTrace)
 	stderrFinished = make(chan bool, 1)
@@ -27,16 +31,33 @@ func init() {
 
 func (c *Client) logStdErr() {
 	for e := range c.writer {
-		if e.level >= c.LogLevel {
+		if e.level >= c.LogLevel && c.matchesNamespace(e.Namespace) {
-			fmt.Fprintf(os.Stderr, "%s\t%s\t%s\t%s\n", e.Timestamp.String(), e.Level, e.Output, e.File)
+			levelStr := colorizeLevelText(e.Level, e.level)
+			nsStr := colorize("["+e.Namespace+"]", colorPurple)
+			fileStr := colorize(e.File, colorGray)
+			fmt.Fprintf(os.Stderr, "%s\t%s\t%s\t%s\t%s\n", e.Timestamp.String(), levelStr, nsStr, e.Output, fileStr)
 		}
 	}
 	stderrFinished <- true
 }
 
-func CreateClient() *Client {
+func (c *Client) matchesNamespace(namespace string) bool {
+	// Empty Namespaces slice means match all
+	if len(c.Namespaces) == 0 {
+		return true
+	}
+	for _, ns := range c.Namespaces {
+		if ns == namespace {
+			return true
+		}
+	}
+	return false
+}
+
+func CreateClient(namespaces ...string) *Client {
 	var client Client
 	client.initialized = true
+	client.Namespaces = namespaces
 	client.writer = make(LogWriter, 1000)
 	sliceTex.Lock()
 	clients = append(clients, &client)
@@ -53,19 +74,19 @@ func Flush() {
 }
 
 func (c *Client) Destroy() error {
-	var otherClients []*Client
 	if !c.initialized {
 		panic(errors.New("cannot delete uninitialized client, did you use CreateClient?"))
 	}
 	sliceTex.Lock()
-	c.writer = nil
 	c.initialized = false
+	var otherClients []*Client
 	for _, x := range clients {
-		if x.initialized {
+		if x != c && x.initialized {
 			otherClients = append(otherClients, x)
 		}
 	}
 	clients = otherClients
+	c.writer = nil
 	sliceTex.Unlock()
 	return nil
 }
@@ -78,9 +99,21 @@ func (c *Client) GetLogLevel() Level {
 }
 
 func createLog(e Entry) {
+	// Track namespace
+	namespacesMux.Lock()
+	namespaces[e.Namespace] = true
+	namespacesMux.Unlock()
+
 	sliceTex.Lock()
 	for _, c := range clients {
 		func(c *Client, e Entry) {
+			if c.writer == nil || !c.initialized {
+				return
+			}
+			// Filter by namespace if client has filters specified
+			if !c.matchesNamespace(e.Namespace) {
+				return
+			}
 			select {
 			case c.writer <- e:
 				// try to clear out one of the older entries
@@ -96,6 +129,18 @@ func createLog(e Entry) {
 	sliceTex.Unlock()
 }
 
+// GetNamespaces returns a list of all namespaces that have been used
+func GetNamespaces() []string {
+	namespacesMux.RLock()
+	defer namespacesMux.RUnlock()
+
+	result := make([]string, 0, len(namespaces))
+	for ns := range namespaces {
+		result = append(result, ns)
+	}
+	return result
+}
+
 func SetLogLevel(level Level) {
 	stderrClient.LogLevel = level
 }
@@ -123,6 +168,7 @@ func Trace(args ...any) {
 		Output:    output,
 		File:      fileInfo(2),
 		Level:     "TRACE",
+		Namespace: DefaultNamespace,
 		level:     LTrace,
 	}
 	createLog(e)
@@ -137,6 +183,7 @@ func Tracef(format string, args ...any) {
 		File:      fileInfo(2),
 		Level:     "TRACE",
 		level:     LTrace,
+		Namespace: DefaultNamespace,
 	}
 	createLog(e)
 }
@@ -150,6 +197,7 @@ func Traceln(args ...any) {
 		File:      fileInfo(2),
 		Level:     "TRACE",
 		level:     LTrace,
+		Namespace: DefaultNamespace,
 	}
 	createLog(e)
 }
@@ -163,6 +211,7 @@ func Debug(args ...any) {
 		File:      fileInfo(2),
 		Level:     "DEBUG",
 		level:     LDebug,
+		Namespace: DefaultNamespace,
 	}
 	createLog(e)
 }
@@ -176,6 +225,7 @@ func Debugf(format string, args ...any) {
 		File:      fileInfo(2),
 		Level:     "DEBUG",
 		level:     LDebug,
+		Namespace: DefaultNamespace,
 	}
 	createLog(e)
 }
@@ -189,6 +239,7 @@ func Debugln(args ...any) {
 		File:      fileInfo(2),
 		Level:     "DEBUG",
 		level:     LDebug,
+		Namespace: DefaultNamespace,
 	}
 	createLog(e)
 }
@@ -202,6 +253,7 @@ func Info(args ...any) {
 		File:      fileInfo(2),
 		Level:     "INFO",
 		level:     LInfo,
+		Namespace: DefaultNamespace,
 	}
 	createLog(e)
 }
@@ -215,6 +267,7 @@ func Infof(format string, args ...any) {
 		File:      fileInfo(2),
 		Level:     "INFO",
 		level:     LInfo,
+		Namespace: DefaultNamespace,
 	}
 	createLog(e)
 }
@@ -228,6 +281,7 @@ func Infoln(args ...any) {
 		File:      fileInfo(2),
 		Level:     "INFO",
 		level:     LInfo,
+		Namespace: DefaultNamespace,
 	}
 	createLog(e)
 }
@@ -241,6 +295,7 @@ func Notice(args ...any) {
 		File:      fileInfo(2),
 		Level:     "NOTICE",
 		level:     LNotice,
+		Namespace: DefaultNamespace,
 	}
 	createLog(e)
 }
@@ -254,6 +309,7 @@ func Noticef(format string, args ...any) {
 		File:      fileInfo(2),
 		Level:     "NOTICE",
 		level:     LNotice,
+		Namespace: DefaultNamespace,
 	}
 	createLog(e)
 }
@@ -267,6 +323,7 @@ func Noticeln(args ...any) {
 		File:      fileInfo(2),
 		Level:     "NOTICE",
 		level:     LNotice,
+		Namespace: DefaultNamespace,
 	}
 	createLog(e)
 }
@@ -280,6 +337,7 @@ func Warn(args ...any) {
 		File:      fileInfo(2),
 		Level:     "WARN",
 		level:     LWarn,
+		Namespace: DefaultNamespace,
 	}
 	createLog(e)
 }
@@ -293,6 +351,7 @@ func Warnf(format string, args ...any) {
 		File:      fileInfo(2),
 		Level:     "WARN",
 		level:     LWarn,
+		Namespace: DefaultNamespace,
 	}
 	createLog(e)
 }
@@ -306,6 +365,7 @@ func Warnln(args ...any) {
 		File:      fileInfo(2),
 		Level:     "WARN",
 		level:     LWarn,
+		Namespace: DefaultNamespace,
 	}
 	createLog(e)
 }
@@ -319,6 +379,7 @@ func Error(args ...any) {
 		File:      fileInfo(2),
 		Level:     "ERROR",
 		level:     LError,
+		Namespace: DefaultNamespace,
 	}
 	createLog(e)
 }
@@ -332,6 +393,7 @@ func Errorf(format string, args ...any) {
 		File:      fileInfo(2),
 		Level:     "ERROR",
 		level:     LError,
+		Namespace: DefaultNamespace,
 	}
 	createLog(e)
 }
@@ -345,6 +407,7 @@ func Errorln(args ...any) {
 		File:      fileInfo(2),
 		Level:     "ERROR",
 		level:     LError,
+		Namespace: DefaultNamespace,
 	}
 	createLog(e)
 }
@@ -358,9 +421,10 @@ func Panic(args ...any) {
 		File:      fileInfo(2),
 		Level:     "PANIC",
 		level:     LPanic,
+		Namespace: DefaultNamespace,
 	}
 	createLog(e)
-	if len(args) >= 0 {
+	if len(args) > 0 {
 		switch args[0].(type) {
 		case error:
 			panic(args[0])
@@ -381,9 +445,10 @@ func Panicf(format string, args ...any) {
 		File:      fileInfo(2),
 		Level:     "PANIC",
 		level:     LPanic,
+		Namespace: DefaultNamespace,
 	}
 	createLog(e)
-	if len(args) >= 0 {
+	if len(args) > 0 {
 		switch args[0].(type) {
 		case error:
 			panic(args[0])
@@ -403,9 +468,10 @@ func Panicln(args ...any) {
 		File:      fileInfo(2),
 		Level:     "PANIC",
 		level:     LPanic,
+		Namespace: DefaultNamespace,
 	}
 	createLog(e)
-	if len(args) >= 0 {
+	if len(args) > 0 {
 		switch args[0].(type) {
 		case error:
 			panic(args[0])
@@ -426,6 +492,7 @@ func Fatal(args ...any) {
 		File:      fileInfo(2),
 		Level:     "FATAL",
 		level:     LFatal,
+		Namespace: DefaultNamespace,
 	}
 	createLog(e)
 	Flush()
@@ -441,6 +508,7 @@ func Fatalf(format string, args ...any) {
 		File:      fileInfo(2),
 		Level:     "FATAL",
 		level:     LFatal,
+		Namespace: DefaultNamespace,
 	}
 	createLog(e)
 	Flush()
@@ -455,6 +523,7 @@ func Fatalln(args ...any) {
 		File:      fileInfo(2),
 		Level:     "FATAL",
 		level:     LFatal,
+		Namespace: DefaultNamespace,
 	}
 	createLog(e)
 	Flush()
@@ -487,3 +556,37 @@ func fileInfo(skip int) string {
 	}
 	return fmt.Sprintf("%s:%d", file, line)
 }
+
+// Broadcast sends an [Entry] to all registered clients. This is the public
+// entry point used by adapter packages (such as the slog handler) that
+// construct entries themselves. The unexported level field is inferred from
+// [Entry.Level] when not already set.
+func Broadcast(e Entry) {
+	if e.level == 0 && e.Level != "" && e.Level != "TRACE" {
+		e.level = parseLevelString(e.Level)
+	}
+	createLog(e)
+}
+
+func parseLevelString(s string) Level {
+	switch s {
+	case "TRACE":
+		return LTrace
+	case "DEBUG":
+		return LDebug
+	case "INFO":
+		return LInfo
+	case "NOTICE":
+		return LNotice
+	case "WARN":
+		return LWarn
+	case "ERROR":
+		return LError
+	case "PANIC":
+		return LPanic
+	case "FATAL":
+		return LFatal
+	default:
+		return LInfo
+	}
+}

log/log_test.go

@@ -4,8 +4,21 @@ import (
 	"strconv"
 	"sync"
 	"testing"
+	"time"
 )
 
+// getEntry reads from a client with a timeout to avoid hanging tests.
+func getEntry(c *Client, timeout time.Duration) (Entry, bool) {
+	ch := make(chan Entry, 1)
+	go func() { ch <- c.Get() }()
+	select {
+	case e := <-ch:
+		return e, true
+	case <-time.After(timeout):
+		return Entry{}, false
+	}
+}
+
 // Test CreateClient() and Client.Destroy()
 func TestCreateDestroy(t *testing.T) {
 	// Ensure only stderr exists at the beginning
@@ -13,7 +26,7 @@ func TestCreateDestroy(t *testing.T) {
 		t.Errorf("Expected 1 client, but found %d", len(clients))
 	}
 	// Create a new client, ensure it's added
-	c := CreateClient()
+	c := CreateClient("test")
 	if len(clients) != 2 {
 		t.Errorf("Expected 2 clients, but found %d", len(clients))
 	}
@@ -27,7 +40,7 @@ func TestCreateDestroy(t *testing.T) {
 // SetLogLevel set log level of logger
 func TestSetLogLevel(t *testing.T) {
 	logLevels := [...]Level{LTrace, LDebug, LInfo, LWarn, LError, LPanic, LFatal}
-	c := CreateClient()
+	c := CreateClient("test")
 	for _, x := range logLevels {
 		c.SetLogLevel(x)
 		if c.GetLogLevel() != x {
@@ -38,7 +51,7 @@ func TestSetLogLevel(t *testing.T) {
 }
 
 func BenchmarkDebugSerial(b *testing.B) {
-	c := CreateClient()
+	c := CreateClient("test")
 	var x sync.WaitGroup
 	x.Add(b.N)
 	for i := 0; i < b.N; i++ {
@@ -55,7 +68,7 @@ func BenchmarkDebugSerial(b *testing.B) {
 // Trace ensure logs come out in the right order
 func TestOrder(t *testing.T) {
 	testString := "Testing trace: "
-	c := CreateClient()
+	c := CreateClient(DefaultNamespace)
 	c.SetLogLevel(LTrace)
 
 	for i := 0; i < 5000; i++ {
@@ -64,70 +77,477 @@ func TestOrder(t *testing.T) {
 			t.Error("Trace input doesn't match output")
 		}
 	}
+	c.Destroy()
 }
 
-// Debug prints out logs on debug level
 func TestDebug(t *testing.T) {
-	Debug("Test of Debug")
+	c := CreateClient(DefaultNamespace)
-	//	if logLevel >= LDebug {
+	c.SetLogLevel(LDebug)
-	//		entry := logger.WithFields(logrus.Fields{})
+
-	//		entry.Data["file"] = fileInfo(2)
+	Debug("debug message")
-	//		entry.Debug(args...)
+	e, ok := getEntry(c, time.Second)
-	//	}
+	if !ok {
+		t.Fatal("timed out waiting for debug entry")
+	}
+	if e.Level != "DEBUG" {
+		t.Errorf("level = %q, want DEBUG", e.Level)
+	}
+	if e.Output != "debug message" {
+		t.Errorf("output = %q, want %q", e.Output, "debug message")
+	}
+	if e.Namespace != DefaultNamespace {
+		t.Errorf("namespace = %q, want %q", e.Namespace, DefaultNamespace)
+	}
+	c.Destroy()
+}
+
+func TestDebugf(t *testing.T) {
+	c := CreateClient(DefaultNamespace)
+	c.SetLogLevel(LDebug)
+
+	Debugf("hello %s %d", "world", 42)
+	e, ok := getEntry(c, time.Second)
+	if !ok {
+		t.Fatal("timed out")
+	}
+	if e.Output != "hello world 42" {
+		t.Errorf("output = %q, want %q", e.Output, "hello world 42")
+	}
+	c.Destroy()
 }
 
-// Info prints out logs on info level
 func TestInfo(t *testing.T) {
-	//	if logLevel >= LInfo {
+	c := CreateClient(DefaultNamespace)
-	//		entry := logger.WithFields(logrus.Fields{})
+	c.SetLogLevel(LInfo)
-	//		entry.Data["file"] = fileInfo(2)
+
-	//		entry.Info(args...)
+	Info("info message")
-	//	}
+	e, ok := getEntry(c, time.Second)
+	if !ok {
+		t.Fatal("timed out waiting for info entry")
+	}
+	if e.Level != "INFO" {
+		t.Errorf("level = %q, want INFO", e.Level)
+	}
+	if e.Output != "info message" {
+		t.Errorf("output = %q, want %q", e.Output, "info message")
+	}
+	c.Destroy()
+}
+
+func TestInfof(t *testing.T) {
+	c := CreateClient(DefaultNamespace)
+	c.SetLogLevel(LInfo)
+
+	Infof("count: %d", 99)
+	e, ok := getEntry(c, time.Second)
+	if !ok {
+		t.Fatal("timed out")
+	}
+	if e.Output != "count: 99" {
+		t.Errorf("output = %q, want %q", e.Output, "count: 99")
+	}
+	c.Destroy()
 }
 
-// Print prints out logs on info level
 func TestPrint(t *testing.T) {
-	//	if logLevel >= LInfo {
+	c := CreateClient(DefaultNamespace)
-	//		entry := logger.WithFields(logrus.Fields{})
+	c.SetLogLevel(LInfo)
-	//		entry.Data["file"] = fileInfo(2)
+
-	//		entry.Info(args...)
+	Print("print message")
-	//	}
+	e, ok := getEntry(c, time.Second)
+	if !ok {
+		t.Fatal("timed out")
+	}
+	// Print is an alias for Info
+	if e.Level != "INFO" {
+		t.Errorf("level = %q, want INFO", e.Level)
+	}
+	if e.Output != "print message" {
+		t.Errorf("output = %q, want %q", e.Output, "print message")
+	}
+	c.Destroy()
+}
+
+func TestPrintf(t *testing.T) {
+	c := CreateClient(DefaultNamespace)
+	c.SetLogLevel(LInfo)
+
+	Printf("formatted %s", "print")
+	e, ok := getEntry(c, time.Second)
+	if !ok {
+		t.Fatal("timed out")
+	}
+	if e.Output != "formatted print" {
+		t.Errorf("output = %q, want %q", e.Output, "formatted print")
+	}
+	c.Destroy()
+}
+
+func TestNotice(t *testing.T) {
+	c := CreateClient(DefaultNamespace)
+	c.SetLogLevel(LNotice)
+
+	Notice("notice message")
+	e, ok := getEntry(c, time.Second)
+	if !ok {
+		t.Fatal("timed out")
+	}
+	if e.Level != "NOTICE" {
+		t.Errorf("level = %q, want NOTICE", e.Level)
+	}
+	c.Destroy()
 }
 
-// Warn prints out logs on warn level
 func TestWarn(t *testing.T) {
-	//	if logLevel >= LWarn {
+	c := CreateClient(DefaultNamespace)
-	//		entry := logger.WithFields(logrus.Fields{})
+	c.SetLogLevel(LWarn)
-	//		entry.Data["file"] = fileInfo(2)
+
-	//		entry.Warn(args...)
+	Warn("warning message")
-	//	}
+	e, ok := getEntry(c, time.Second)
+	if !ok {
+		t.Fatal("timed out waiting for warn entry")
+	}
+	if e.Level != "WARN" {
+		t.Errorf("level = %q, want WARN", e.Level)
+	}
+	if e.Output != "warning message" {
+		t.Errorf("output = %q, want %q", e.Output, "warning message")
+	}
+	c.Destroy()
+}
+
+func TestWarnf(t *testing.T) {
+	c := CreateClient(DefaultNamespace)
+	c.SetLogLevel(LWarn)
+
+	Warnf("warn %d", 1)
+	e, ok := getEntry(c, time.Second)
+	if !ok {
+		t.Fatal("timed out")
+	}
+	if e.Output != "warn 1" {
+		t.Errorf("output = %q, want %q", e.Output, "warn 1")
+	}
+	c.Destroy()
 }
 
-// Error prints out logs on error level
 func TestError(t *testing.T) {
-	//	if logLevel >= LError {
+	c := CreateClient(DefaultNamespace)
-	//		entry := logger.WithFields(logrus.Fields{})
+	c.SetLogLevel(LError)
-	//		entry.Data["file"] = fileInfo(2)
+
-	//		entry.Error(args...)
+	Error("error message")
-	//	}
+	e, ok := getEntry(c, time.Second)
+	if !ok {
+		t.Fatal("timed out waiting for error entry")
+	}
+	if e.Level != "ERROR" {
+		t.Errorf("level = %q, want ERROR", e.Level)
+	}
+	if e.Output != "error message" {
+		t.Errorf("output = %q, want %q", e.Output, "error message")
+	}
+	c.Destroy()
 }
 
-// Fatal prints out logs on fatal level
+func TestErrorf(t *testing.T) {
-func TestFatal(t *testing.T) {
+	c := CreateClient(DefaultNamespace)
-	//	if logLevel >= LFatal {
+	c.SetLogLevel(LError)
-	//		entry := logger.WithFields(logrus.Fields{})
+
-	//		entry.Data["file"] = fileInfo(2)
+	Errorf("err: %s", "something broke")
-	//		entry.Fatal(args...)
+	e, ok := getEntry(c, time.Second)
-	//	}
+	if !ok {
+		t.Fatal("timed out")
+	}
+	if e.Output != "err: something broke" {
+		t.Errorf("output = %q, want %q", e.Output, "err: something broke")
+	}
+	c.Destroy()
 }
 
-// Panic prints out logs on panic level
 func TestPanic(t *testing.T) {
-	//	if logLevel >= LPanic {
+	c := CreateClient(DefaultNamespace)
-	//		entry := logger.WithFields(logrus.Fields{})
+	c.SetLogLevel(LPanic)
-	//		entry.Data["file"] = fileInfo(2)
+
-	//		entry.Panic(args...)
+	defer func() {
-	//	}
+		r := recover()
+		if r == nil {
+			t.Error("expected panic, got nil")
+		}
+		c.Destroy()
+	}()
+
+	Panic("panic message")
+}
+
+func TestPanicf(t *testing.T) {
+	c := CreateClient(DefaultNamespace)
+	c.SetLogLevel(LPanic)
+
+	defer func() {
+		r := recover()
+		if r == nil {
+			t.Error("expected panic, got nil")
+		}
+		c.Destroy()
+	}()
+
+	Panicf("panic %d", 42)
+}
+
+func TestPanicln(t *testing.T) {
+	c := CreateClient(DefaultNamespace)
+	c.SetLogLevel(LPanic)
+
+	defer func() {
+		r := recover()
+		if r == nil {
+			t.Error("expected panic, got nil")
+		}
+		c.Destroy()
+	}()
+
+	Panicln("panic line")
+}
+
+// TestLogLevelFiltering verifies that the client's log level is stored correctly.
+// Note: level filtering only applies to stderr output, not to client channels.
+// All entries matching the namespace are delivered to the client channel regardless of level.
+func TestLogLevelFiltering(t *testing.T) {
+	c := CreateClient(DefaultNamespace)
+	c.SetLogLevel(LWarn)
+
+	if c.GetLogLevel() != LWarn {
+		t.Errorf("expected log level LWarn, got %d", c.GetLogLevel())
+	}
+
+	// Both entries arrive at the client channel (level filtering is stderr-only)
+	Info("info message")
+	Warn("warn message")
+
+	e1, ok := getEntry(c, time.Second)
+	if !ok {
+		t.Fatal("timed out waiting for first entry")
+	}
+	if e1.Output != "info message" {
+		t.Errorf("expected 'info message', got %q", e1.Output)
+	}
+
+	e2, ok := getEntry(c, time.Second)
+	if !ok {
+		t.Fatal("timed out waiting for second entry")
+	}
+	if e2.Output != "warn message" {
+		t.Errorf("expected 'warn message', got %q", e2.Output)
+	}
+	c.Destroy()
+}
+
+// TestNamespaceFiltering verifies clients only receive matching namespaces.
+func TestNamespaceFiltering(t *testing.T) {
+	c := CreateClient("api")
+	c.SetLogLevel(LTrace)
+
+	apiLogger := NewLogger("api")
+	dbLogger := NewLogger("database")
+
+	// Log to database namespace — should not arrive at "api" client
+	dbLogger.Info("db message")
+
+	// Log to api namespace — should arrive
+	apiLogger.Info("api message")
+
+	e, ok := getEntry(c, time.Second)
+	if !ok {
+		t.Fatal("timed out waiting for api entry")
+	}
+	if e.Output != "api message" {
+		t.Errorf("expected 'api message', got %q", e.Output)
+	}
+	if e.Namespace != "api" {
+		t.Errorf("namespace = %q, want 'api'", e.Namespace)
+	}
+	c.Destroy()
+}
+
+// TestMultiNamespaceClient verifies a client subscribed to multiple namespaces.
+func TestMultiNamespaceClient(t *testing.T) {
+	c := CreateClient("api", "auth")
+	c.SetLogLevel(LTrace)
+
+	apiLogger := NewLogger("api")
+	authLogger := NewLogger("auth")
+	dbLogger := NewLogger("database")
+
+	dbLogger.Info("db message")   // filtered out
+	apiLogger.Info("api message") // should arrive
+	authLogger.Info("auth message") // should arrive
+
+	e1, ok := getEntry(c, time.Second)
+	if !ok {
+		t.Fatal("timed out waiting for first entry")
+	}
+	if e1.Output != "api message" {
+		t.Errorf("first entry = %q, want 'api message'", e1.Output)
+	}
+
+	e2, ok := getEntry(c, time.Second)
+	if !ok {
+		t.Fatal("timed out waiting for second entry")
+	}
+	if e2.Output != "auth message" {
+		t.Errorf("second entry = %q, want 'auth message'", e2.Output)
+	}
+	c.Destroy()
+}
+
+// TestGetNamespaces verifies the namespace registry.
+func TestGetNamespaces(t *testing.T) {
+	l := NewLogger("test-ns-registry")
+	l.Info("register this namespace")
+
+	nss := GetNamespaces()
+	found := false
+	for _, ns := range nss {
+		if ns == "test-ns-registry" {
+			found = true
+			break
+		}
+	}
+	if !found {
+		t.Errorf("expected 'test-ns-registry' in GetNamespaces(), got %v", nss)
+	}
+}
+
+// TestLoggerDebugln verifies the Debugln method on Logger.
+func TestLoggerDebugln(t *testing.T) {
+	c := CreateClient("debugln-test")
+	c.SetLogLevel(LDebug)
+
+	l := NewLogger("debugln-test")
+	l.Debugln("debugln message")
+
+	e, ok := getEntry(c, time.Second)
+	if !ok {
+		t.Fatal("timed out")
+	}
+	if e.Level != "DEBUG" {
+		t.Errorf("level = %q, want DEBUG", e.Level)
+	}
+	// Sprintln appends a newline
+	if e.Output != "debugln message\n" {
+		t.Errorf("output = %q, want %q", e.Output, "debugln message\n")
+	}
+	c.Destroy()
+}
+
+// TestNewLoggerEmptyNamespace verifies empty namespace defaults to DefaultNamespace.
+func TestNewLoggerEmptyNamespace(t *testing.T) {
+	l := NewLogger("")
+	if l.Namespace != DefaultNamespace {
+		t.Errorf("namespace = %q, want %q", l.Namespace, DefaultNamespace)
+	}
+}
+
+// TestFileInfo verifies fileInfo returns a non-empty file:line string.
+func TestFileInfo(t *testing.T) {
+	fi := fileInfo(1)
+	if fi == "" || fi == "<???>:1" {
+		t.Errorf("fileInfo returned unexpected value: %q", fi)
+	}
+}
+
+// TestColorize verifies color wrapping.
+func TestColorize(t *testing.T) {
+	SetColorEnabled(true)
+	result := colorize("hello", colorRed)
+	expected := colorRed + "hello" + colorReset
+	if result != expected {
+		t.Errorf("colorize with color enabled: got %q, want %q", result, expected)
+	}
+
+	SetColorEnabled(false)
+	result = colorize("hello", colorRed)
+	if result != "hello" {
+		t.Errorf("colorize with color disabled: got %q, want %q", result, "hello")
+	}
+
+	// Restore default
+	SetColorEnabled(true)
+}
+
+// TestParseLevelString verifies level string parsing.
+func TestParseLevelString(t *testing.T) {
+	tests := []struct {
+		input string
+		want  Level
+	}{
+		{"TRACE", LTrace},
+		{"DEBUG", LDebug},
+		{"INFO", LInfo},
+		{"NOTICE", LNotice},
+		{"WARN", LWarn},
+		{"ERROR", LError},
+		{"PANIC", LPanic},
+		{"FATAL", LFatal},
+		{"UNKNOWN", LInfo}, // default
+		{"", LInfo},        // default
+	}
+	for _, tt := range tests {
+		got := parseLevelString(tt.input)
+		if got != tt.want {
+			t.Errorf("parseLevelString(%q) = %d, want %d", tt.input, got, tt.want)
+		}
+	}
+}
+
+// TestBroadcast verifies the public Broadcast function.
+func TestBroadcast(t *testing.T) {
+	c := CreateClient("broadcast-ns")
+	c.SetLogLevel(LTrace)
+
+	e := Entry{
+		Timestamp: time.Now(),
+		Output:    "broadcast test",
+		File:      "test.go:1",
+		Level:     "WARN",
+		Namespace: "broadcast-ns",
+	}
+	Broadcast(e)
+
+	got, ok := getEntry(c, time.Second)
+	if !ok {
+		t.Fatal("timed out")
+	}
+	if got.Output != "broadcast test" {
+		t.Errorf("output = %q, want %q", got.Output, "broadcast test")
+	}
+	if got.Level != "WARN" {
+		t.Errorf("level = %q, want WARN", got.Level)
+	}
+	c.Destroy()
+}
+
+// TestMatchesNamespace verifies the namespace matching helper.
+func TestMatchesNamespace(t *testing.T) {
+	// Client with no namespace filter matches everything
+	c := CreateClient()
+	if !c.matchesNamespace("anything") {
+		t.Error("empty Namespaces should match all")
+	}
+	c.Destroy()
+
+	// Client with specific namespaces
+	c2 := CreateClient("api", "auth")
+	if !c2.matchesNamespace("api") {
+		t.Error("should match 'api'")
+	}
+	if !c2.matchesNamespace("auth") {
+		t.Error("should match 'auth'")
+	}
+	if c2.matchesNamespace("database") {
+		t.Error("should not match 'database'")
+	}
+	c2.Destroy()
 }
 
 func TestFlush(t *testing.T) {

log/logger.go

@@ -8,7 +8,14 @@ import (
 )
 
 func Default() *Logger {
-	return &Logger{FileInfoDepth: 0}
+	return &Logger{FileInfoDepth: 0, Namespace: DefaultNamespace}
+}
+
+func NewLogger(namespace string) *Logger {
+	if namespace == "" {
+		namespace = DefaultNamespace
+	}
+	return &Logger{FileInfoDepth: 0, Namespace: namespace}
 }
 
 func (l *Logger) SetInfoDepth(depth int) {
@@ -21,9 +28,10 @@ func (l Logger) Trace(args ...any) {
 	e := Entry{
 		Timestamp: time.Now(),
 		Output:    output,
-		File:      fileInfo(l.FileInfoDepth),
+		File:      fileInfo(2 + l.FileInfoDepth),
 		Level:     "TRACE",
 		level:     LTrace,
+		Namespace: l.Namespace,
 	}
 	createLog(e)
 }
@@ -34,9 +42,10 @@ func (l Logger) Tracef(format string, args ...any) {
 	e := Entry{
 		Timestamp: time.Now(),
 		Output:    output,
-		File:      fileInfo(l.FileInfoDepth),
+		File:      fileInfo(2 + l.FileInfoDepth),
 		Level:     "TRACE",
 		level:     LTrace,
+		Namespace: l.Namespace,
 	}
 	createLog(e)
 }
@@ -47,9 +56,10 @@ func (l Logger) Traceln(args ...any) {
 	e := Entry{
 		Timestamp: time.Now(),
 		Output:    output,
-		File:      fileInfo(l.FileInfoDepth),
+		File:      fileInfo(2 + l.FileInfoDepth),
 		Level:     "TRACE",
 		level:     LTrace,
+		Namespace: l.Namespace,
 	}
 	createLog(e)
 }
@@ -60,9 +70,10 @@ func (l Logger) Debug(args ...any) {
 	e := Entry{
 		Timestamp: time.Now(),
 		Output:    output,
-		File:      fileInfo(l.FileInfoDepth),
+		File:      fileInfo(2 + l.FileInfoDepth),
 		Level:     "DEBUG",
 		level:     LDebug,
+		Namespace: l.Namespace,
 	}
 	createLog(e)
 }
@@ -73,9 +84,24 @@ func (l Logger) Debugf(format string, args ...any) {
 	e := Entry{
 		Timestamp: time.Now(),
 		Output:    output,
-		File:      fileInfo(l.FileInfoDepth),
+		File:      fileInfo(2 + l.FileInfoDepth),
 		Level:     "DEBUG",
 		level:     LDebug,
+		Namespace: l.Namespace,
+	}
+	createLog(e)
+}
+
+// Debugln prints out logs on debug level with a newline
+func (l Logger) Debugln(args ...any) {
+	output := fmt.Sprintln(args...)
+	e := Entry{
+		Timestamp: time.Now(),
+		Output:    output,
+		File:      fileInfo(2 + l.FileInfoDepth),
+		Level:     "DEBUG",
+		level:     LDebug,
+		Namespace: l.Namespace,
 	}
 	createLog(e)
 }
@@ -86,9 +112,10 @@ func (l Logger) Info(args ...any) {
 	e := Entry{
 		Timestamp: time.Now(),
 		Output:    output,
-		File:      fileInfo(l.FileInfoDepth),
+		File:      fileInfo(2 + l.FileInfoDepth),
 		Level:     "INFO",
 		level:     LInfo,
+		Namespace: l.Namespace,
 	}
 	createLog(e)
 }
@@ -99,9 +126,10 @@ func (l Logger) Infof(format string, args ...any) {
 	e := Entry{
 		Timestamp: time.Now(),
 		Output:    output,
-		File:      fileInfo(l.FileInfoDepth),
+		File:      fileInfo(2 + l.FileInfoDepth),
 		Level:     "INFO",
 		level:     LInfo,
+		Namespace: l.Namespace,
 	}
 	createLog(e)
 }
@@ -112,9 +140,10 @@ func (l Logger) Infoln(args ...any) {
 	e := Entry{
 		Timestamp: time.Now(),
 		Output:    output,
-		File:      fileInfo(l.FileInfoDepth),
+		File:      fileInfo(2 + l.FileInfoDepth),
 		Level:     "INFO",
 		level:     LInfo,
+		Namespace: l.Namespace,
 	}
 	createLog(e)
 }
@@ -125,9 +154,10 @@ func (l Logger) Notice(args ...any) {
 	e := Entry{
 		Timestamp: time.Now(),
 		Output:    output,
-		File:      fileInfo(l.FileInfoDepth),
+		File:      fileInfo(2 + l.FileInfoDepth),
 		Level:     "NOTICE",
 		level:     LNotice,
+		Namespace: l.Namespace,
 	}
 	createLog(e)
 }
@@ -138,9 +168,10 @@ func (l Logger) Noticef(format string, args ...any) {
 	e := Entry{
 		Timestamp: time.Now(),
 		Output:    output,
-		File:      fileInfo(l.FileInfoDepth),
+		File:      fileInfo(2 + l.FileInfoDepth),
 		Level:     "NOTICE",
 		level:     LNotice,
+		Namespace: l.Namespace,
 	}
 	createLog(e)
 }
@@ -151,9 +182,10 @@ func (l Logger) Noticeln(args ...any) {
 	e := Entry{
 		Timestamp: time.Now(),
 		Output:    output,
-		File:      fileInfo(l.FileInfoDepth),
+		File:      fileInfo(2 + l.FileInfoDepth),
 		Level:     "NOTICE",
 		level:     LNotice,
+		Namespace: l.Namespace,
 	}
 	createLog(e)
 }
@@ -164,9 +196,10 @@ func (l Logger) Warn(args ...any) {
 	e := Entry{
 		Timestamp: time.Now(),
 		Output:    output,
-		File:      fileInfo(l.FileInfoDepth),
+		File:      fileInfo(2 + l.FileInfoDepth),
 		Level:     "WARN",
 		level:     LWarn,
+		Namespace: l.Namespace,
 	}
 	createLog(e)
 }
@@ -177,9 +210,10 @@ func (l Logger) Warnf(format string, args ...any) {
 	e := Entry{
 		Timestamp: time.Now(),
 		Output:    output,
-		File:      fileInfo(l.FileInfoDepth),
+		File:      fileInfo(2 + l.FileInfoDepth),
 		Level:     "WARN",
 		level:     LWarn,
+		Namespace: l.Namespace,
 	}
 	createLog(e)
 }
@@ -190,9 +224,10 @@ func (l Logger) Warnln(args ...any) {
 	e := Entry{
 		Timestamp: time.Now(),
 		Output:    output,
-		File:      fileInfo(l.FileInfoDepth),
+		File:      fileInfo(2 + l.FileInfoDepth),
 		Level:     "WARN",
 		level:     LWarn,
+		Namespace: l.Namespace,
 	}
 	createLog(e)
 }
@@ -203,9 +238,10 @@ func (l Logger) Error(args ...any) {
 	e := Entry{
 		Timestamp: time.Now(),
 		Output:    output,
-		File:      fileInfo(l.FileInfoDepth),
+		File:      fileInfo(2 + l.FileInfoDepth),
 		Level:     "ERROR",
 		level:     LError,
+		Namespace: l.Namespace,
 	}
 	createLog(e)
 }
@@ -216,9 +252,10 @@ func (l Logger) Errorf(format string, args ...any) {
 	e := Entry{
 		Timestamp: time.Now(),
 		Output:    output,
-		File:      fileInfo(l.FileInfoDepth),
+		File:      fileInfo(2 + l.FileInfoDepth),
 		Level:     "ERROR",
 		level:     LError,
+		Namespace: l.Namespace,
 	}
 	createLog(e)
 }
@@ -229,9 +266,10 @@ func (l Logger) Errorln(args ...any) {
 	e := Entry{
 		Timestamp: time.Now(),
 		Output:    output,
-		File:      fileInfo(l.FileInfoDepth),
+		File:      fileInfo(2 + l.FileInfoDepth),
 		Level:     "ERROR",
 		level:     LError,
+		Namespace: l.Namespace,
 	}
 	createLog(e)
 }
@@ -242,12 +280,13 @@ func (l Logger) Panic(args ...any) {
 	e := Entry{
 		Timestamp: time.Now(),
 		Output:    output,
-		File:      fileInfo(l.FileInfoDepth),
+		File:      fileInfo(2 + l.FileInfoDepth),
 		Level:     "PANIC",
 		level:     LPanic,
+		Namespace: l.Namespace,
 	}
 	createLog(e)
-	if len(args) >= 0 {
+	if len(args) > 0 {
 		switch args[0].(type) {
 		case error:
 			panic(args[0])
@@ -265,12 +304,13 @@ func (l Logger) Panicf(format string, args ...any) {
 	e := Entry{
 		Timestamp: time.Now(),
 		Output:    output,
-		File:      fileInfo(l.FileInfoDepth),
+		File:      fileInfo(2 + l.FileInfoDepth),
 		Level:     "PANIC",
 		level:     LPanic,
+		Namespace: l.Namespace,
 	}
 	createLog(e)
-	if len(args) >= 0 {
+	if len(args) > 0 {
 		switch args[0].(type) {
 		case error:
 			panic(args[0])
@@ -288,12 +328,13 @@ func (l Logger) Panicln(args ...any) {
 	e := Entry{
 		Timestamp: time.Now(),
 		Output:    output,
-		File:      fileInfo(l.FileInfoDepth),
+		File:      fileInfo(2 + l.FileInfoDepth),
 		Level:     "PANIC",
 		level:     LPanic,
+		Namespace: l.Namespace,
 	}
 	createLog(e)
-	if len(args) >= 0 {
+	if len(args) > 0 {
 		switch args[0].(type) {
 		case error:
 			panic(args[0])
@@ -311,9 +352,10 @@ func (l Logger) Fatal(args ...any) {
 	e := Entry{
 		Timestamp: time.Now(),
 		Output:    output,
-		File:      fileInfo(l.FileInfoDepth),
+		File:      fileInfo(2 + l.FileInfoDepth),
 		Level:     "FATAL",
 		level:     LFatal,
+		Namespace: l.Namespace,
 	}
 	createLog(e)
 	Flush()
@@ -326,9 +368,10 @@ func (l Logger) Fatalf(format string, args ...any) {
 	e := Entry{
 		Timestamp: time.Now(),
 		Output:    output,
-		File:      fileInfo(l.FileInfoDepth),
+		File:      fileInfo(2 + l.FileInfoDepth),
 		Level:     "FATAL",
 		level:     LFatal,
+		Namespace: l.Namespace,
 	}
 	createLog(e)
 	Flush()
@@ -341,9 +384,10 @@ func (l Logger) Fatalln(args ...any) {
 	e := Entry{
 		Timestamp: time.Now(),
 		Output:    output,
-		File:      fileInfo(l.FileInfoDepth),
+		File:      fileInfo(2 + l.FileInfoDepth),
 		Level:     "FATAL",
 		level:     LFatal,
+		Namespace: l.Namespace,
 	}
 	createLog(e)
 	Flush()

log/types.go

@@ -13,12 +13,15 @@ const (
 	LFatal
 )
 
+const DefaultNamespace = "default"
+
 type (
 	LogWriter chan Entry
 	Level     int
 
 	Client struct {
-		LogLevel    Level `json:"level"`
+		LogLevel    Level    `json:"level"`
+		Namespaces  []string `json:"namespaces"` // Empty slice means all namespaces
 		writer      LogWriter
 		initialized bool
 	}
@@ -27,9 +30,11 @@ type (
 		Output    string    `json:"output"`
 		File      string    `json:"file"`
 		Level     string    `json:"level"`
+		Namespace string    `json:"namespace"`
 		level     Level
 	}
 	Logger struct {
 		FileInfoDepth int
+		Namespace     string
 	}
 )

main.go

@@ -5,20 +5,33 @@ import (
 	"net/http"
 	"time"
 
-	"github.com/taigrr/log-socket/browser"
+	"github.com/taigrr/log-socket/v2/browser"
-	logger "github.com/taigrr/log-socket/log"
+	logger "github.com/taigrr/log-socket/v2/log"
-	"github.com/taigrr/log-socket/ws"
+	"github.com/taigrr/log-socket/v2/ws"
 )
 
 var addr = flag.String("addr", "0.0.0.0:8080", "http service address")
 
 func generateLogs() {
+	// Create loggers for different namespaces
+	apiLogger := logger.NewLogger("api")
+	dbLogger := logger.NewLogger("database")
+	authLogger := logger.NewLogger("auth")
+	
 	for {
-		logger.Info("This is an info log!")
+		logger.Info("This is a default namespace log!")
-		logger.Trace("This is a trace log!")
+		apiLogger.Info("API request received")
-		logger.Debug("This is a debug log!")
+		apiLogger.Debug("Processing API call")
-		logger.Warn("This is a warn log!")
+		
-		logger.Error("This is an error log!")
+		dbLogger.Info("Database query executed")
+		dbLogger.Warn("Slow query detected")
+		
+		authLogger.Info("User authentication successful")
+		authLogger.Error("Failed login attempt detected")
+		
+		logger.Trace("This is a trace log in default namespace!")
+		logger.Warn("This is a warning in default namespace!")
+		
 		time.Sleep(2 * time.Second)
 	}
 }
@@ -27,6 +40,7 @@ func main() {
 	defer logger.Flush()
 	flag.Parse()
 	http.HandleFunc("/ws", ws.LogSocketHandler)
+	http.HandleFunc("/api/namespaces", ws.NamespacesHandler)
 	http.HandleFunc("/", browser.LogSocketViewHandler)
 	go generateLogs()
 	logger.Fatal(http.ListenAndServe(*addr, nil))

slog/handler.go

@@ -0,0 +1,165 @@
+// Package slog provides a [log/slog.Handler] that routes structured log
+// records into the log-socket broadcasting system, giving every slog-based
+// caller free WebSocket streaming and the browser viewer UI.
+package slog
+
+import (
+	"context"
+	"fmt"
+	"log/slog"
+	"runtime"
+	"strings"
+
+	"github.com/taigrr/log-socket/v2/log"
+)
+
+// Handler implements [slog.Handler] by converting each [slog.Record] into a
+// log-socket [log.Entry] and feeding it through the normal broadcast path.
+//
+// Attributes accumulated via [Handler.WithAttrs] are prepended to the log
+// message as key=value pairs. Groups set via [Handler.WithGroup] prefix
+// attribute keys with "group.".
+type Handler struct {
+	namespace string
+	level     slog.Level
+	attrs     []slog.Attr
+	groups    []string
+}
+
+// ensure interface compliance at compile time.
+var _ slog.Handler = (*Handler)(nil)
+
+// Option configures a [Handler].
+type Option func(*Handler)
+
+// WithNamespace sets the log-socket namespace for entries produced by this
+// handler.  If empty, [log.DefaultNamespace] is used.
+func WithNamespace(ns string) Option {
+	return func(h *Handler) {
+		h.namespace = ns
+	}
+}
+
+// WithLevel sets the minimum slog level the handler will accept.
+func WithLevel(l slog.Level) Option {
+	return func(h *Handler) {
+		h.level = l
+	}
+}
+
+// NewHandler returns a new [Handler] that writes to the log-socket broadcast
+// system.  Options may be used to set the namespace and minimum level.
+func NewHandler(opts ...Option) *Handler {
+	h := &Handler{
+		namespace: log.DefaultNamespace,
+		level:     slog.LevelDebug,
+	}
+	for _, o := range opts {
+		o(h)
+	}
+	return h
+}
+
+// Enabled reports whether the handler is configured to process records at
+// the given level.
+func (h *Handler) Enabled(_ context.Context, level slog.Level) bool {
+	return level >= h.level
+}
+
+// Handle converts r into a log-socket Entry and broadcasts it.
+func (h *Handler) Handle(_ context.Context, r slog.Record) error {
+	var b strings.Builder
+	b.WriteString(r.Message)
+
+	// Append pre-collected attrs.
+	for _, a := range h.attrs {
+		writeAttr(&b, h.groups, a)
+	}
+
+	// Append record-level attrs.
+	r.Attrs(func(a slog.Attr) bool {
+		writeAttr(&b, h.groups, a)
+		return true
+	})
+
+	file := "???"
+	if r.PC != 0 {
+		fs := runtime.CallersFrames([]uintptr{r.PC})
+		f, _ := fs.Next()
+		if f.File != "" {
+			short := f.File
+			if idx := strings.LastIndex(short, "/"); idx >= 0 {
+				short = short[idx+1:]
+			}
+			file = fmt.Sprintf("%s:%d", short, f.Line)
+		}
+	}
+
+	e := log.Entry{
+		Timestamp: r.Time,
+		Output:    b.String(),
+		File:      file,
+		Level:     slogLevelToString(r.Level),
+		Namespace: h.namespace,
+	}
+	log.Broadcast(e)
+	return nil
+}
+
+// WithAttrs returns a new Handler with the given attributes appended.
+func (h *Handler) WithAttrs(attrs []slog.Attr) slog.Handler {
+	h2 := h.clone()
+	h2.attrs = append(h2.attrs, attrs...)
+	return h2
+}
+
+// WithGroup returns a new Handler where subsequent attributes are nested
+// under the given group name.
+func (h *Handler) WithGroup(name string) slog.Handler {
+	if name == "" {
+		return h
+	}
+	h2 := h.clone()
+	h2.groups = append(h2.groups, name)
+	return h2
+}
+
+func (h *Handler) clone() *Handler {
+	h2 := &Handler{
+		namespace: h.namespace,
+		level:     h.level,
+		attrs:     make([]slog.Attr, len(h.attrs)),
+		groups:    make([]string, len(h.groups)),
+	}
+	copy(h2.attrs, h.attrs)
+	copy(h2.groups, h.groups)
+	return h2
+}
+
+func writeAttr(b *strings.Builder, groups []string, a slog.Attr) {
+	a.Value = a.Value.Resolve()
+	if a.Equal(slog.Attr{}) {
+		return
+	}
+	b.WriteByte(' ')
+	for _, g := range groups {
+		b.WriteString(g)
+		b.WriteByte('.')
+	}
+	b.WriteString(a.Key)
+	b.WriteByte('=')
+	b.WriteString(a.Value.String())
+}
+
+func slogLevelToString(l slog.Level) string {
+	switch {
+	case l >= slog.LevelError:
+		return "ERROR"
+	case l >= slog.LevelWarn:
+		return "WARN"
+	case l >= slog.LevelInfo:
+		return "INFO"
+	default:
+		return "DEBUG"
+	}
+}

slog/handler_test.go

@@ -0,0 +1,118 @@
+package slog
+
+import (
+	"context"
+	"log/slog"
+	"testing"
+	"time"
+
+	"github.com/taigrr/log-socket/v2/log"
+)
+
+// getWithTimeout reads from a log client with a timeout to avoid hanging tests.
+func getWithTimeout(c *log.Client, timeout time.Duration) (log.Entry, bool) {
+	ch := make(chan log.Entry, 1)
+	go func() { ch <- c.Get() }()
+	select {
+	case e := <-ch:
+		return e, true
+	case <-time.After(timeout):
+		return log.Entry{}, false
+	}
+}
+
+func TestHandler_Enabled(t *testing.T) {
+	h := NewHandler(WithLevel(slog.LevelWarn))
+	if h.Enabled(context.Background(), slog.LevelInfo) {
+		t.Error("expected Info to be disabled when min level is Warn")
+	}
+	if !h.Enabled(context.Background(), slog.LevelWarn) {
+		t.Error("expected Warn to be enabled")
+	}
+	if !h.Enabled(context.Background(), slog.LevelError) {
+		t.Error("expected Error to be enabled")
+	}
+}
+
+func TestHandler_Handle(t *testing.T) {
+	c := log.CreateClient()
+	defer c.Destroy()
+	c.SetLogLevel(log.LTrace)
+
+	h := NewHandler(WithNamespace("test-ns"))
+	logger := slog.New(h)
+
+	logger.Info("hello world", "key", "value")
+
+	e, ok := getWithTimeout(c, time.Second)
+	if !ok {
+		t.Fatal("timed out waiting for log entry")
+	}
+	if e.Namespace != "test-ns" {
+		t.Errorf("namespace = %q, want %q", e.Namespace, "test-ns")
+	}
+	if e.Level != "INFO" {
+		t.Errorf("level = %q, want INFO", e.Level)
+	}
+	if e.Output == "" {
+		t.Error("output should not be empty")
+	}
+}
+
+func TestHandler_WithAttrs(t *testing.T) {
+	c := log.CreateClient()
+	defer c.Destroy()
+	c.SetLogLevel(log.LTrace)
+
+	h := NewHandler()
+	h2 := h.WithAttrs([]slog.Attr{slog.String("service", "api")})
+	logger := slog.New(h2)
+
+	logger.Info("request")
+
+	e, ok := getWithTimeout(c, time.Second)
+	if !ok {
+		t.Fatal("timed out")
+	}
+	if e.Output != "request service=api" {
+		t.Errorf("output = %q, want %q", e.Output, "request service=api")
+	}
+}
+
+func TestHandler_WithGroup(t *testing.T) {
+	c := log.CreateClient()
+	defer c.Destroy()
+	c.SetLogLevel(log.LTrace)
+
+	h := NewHandler()
+	h2 := h.WithGroup("http").WithAttrs([]slog.Attr{slog.Int("status", 200)})
+	logger := slog.New(h2)
+
+	logger.Info("done")
+
+	e, ok := getWithTimeout(c, time.Second)
+	if !ok {
+		t.Fatal("timed out")
+	}
+	if e.Output != "done http.status=200" {
+		t.Errorf("output = %q, want %q", e.Output, "done http.status=200")
+	}
+}
+
+func TestSlogLevelMapping(t *testing.T) {
+	tests := []struct {
+		level slog.Level
+		want  string
+	}{
+		{slog.LevelDebug, "DEBUG"},
+		{slog.LevelInfo, "INFO"},
+		{slog.LevelWarn, "WARN"},
+		{slog.LevelError, "ERROR"},
+	}
+	for _, tt := range tests {
+		got := slogLevelToString(tt.level)
+		if got != tt.want {
+			t.Errorf("slogLevelToString(%v) = %q, want %q", tt.level, got, tt.want)
+		}
+	}
+}

ws/namespaces.go

@@ -0,0 +1,17 @@
+package ws
+
+import (
+	"encoding/json"
+	"net/http"
+
+	logger "github.com/taigrr/log-socket/v2/log"
+)
+
+// NamespacesHandler returns a JSON list of all namespaces that have been used
+func NamespacesHandler(w http.ResponseWriter, r *http.Request) {
+	namespaces := logger.GetNamespaces()
+	w.Header().Set("Content-Type", "application/json")
+	json.NewEncoder(w).Encode(map[string]interface{}{
+		"namespaces": namespaces,
+	})
+}

ws/server.go

@@ -3,9 +3,10 @@ package ws
 import (
 	"encoding/json"
 	"net/http"
+	"strings"
 
 	"github.com/gorilla/websocket"
-	logger "github.com/taigrr/log-socket/log"
+	logger "github.com/taigrr/log-socket/v2/log"
 )
 
 var upgrader = websocket.Upgrader{} // use default options
@@ -15,13 +16,21 @@ func SetUpgrader(u websocket.Upgrader) {
 }
 
 func LogSocketHandler(w http.ResponseWriter, r *http.Request) {
+	// Get namespaces from query parameter, comma-separated
+	// Empty or missing means all namespaces
+	namespacesParam := r.URL.Query().Get("namespaces")
+	var namespaces []string
+	if namespacesParam != "" {
+		namespaces = strings.Split(namespacesParam, ",")
+	}
+	
 	c, err := upgrader.Upgrade(w, r, nil)
 	if err != nil {
 		logger.Error("upgrade:", err)
 		return
 	}
 	defer c.Close()
-	lc := logger.CreateClient()
+	lc := logger.CreateClient(namespaces...)
 	defer lc.Destroy()
 	lc.SetLogLevel(logger.LTrace)
 	logger.Info("Websocket client attached.")