feat: add event type and action filtering

Configure which events to forward via comma-separated 'events' config.
Supports event-level ('push', 'pull_request') or event:action-level
('pull_request:opened', 'issues:closed') filtering.

Empty/omitted = forward everything (backwards compatible).

main.go

@@ -26,25 +26,57 @@ func main() {
 	signal := signalcli.NewClient(cfg.SignalURL, cfg.SignalAccount)
 	handle := githubevents.New(cfg.WebhookSecret)
 
-	notifier := &notifier{
+	n := &notifier{
 		signal:    signal,
 		recipient: cfg.SignalRecipient,
 		groupID:   cfg.SignalGroupID,
+		filter:    cfg.Events,
 	}
 
-	// Register event handlers.
-	handle.OnPushEventAny(notifier.onPush)
-	handle.OnIssuesEventAny(notifier.onIssue)
-	handle.OnIssueCommentEventAny(notifier.onIssueComment)
-	handle.OnPullRequestEventAny(notifier.onPR)
-	handle.OnPullRequestReviewEventAny(notifier.onPRReview)
-	handle.OnPullRequestReviewCommentEventAny(notifier.onPRReviewComment)
-	handle.OnReleaseEventAny(notifier.onRelease)
-	handle.OnStarEventAny(notifier.onStar)
-	handle.OnForkEventAny(notifier.onFork)
-	handle.OnWorkflowRunEventAny(notifier.onWorkflowRun)
-	handle.OnCreateEventAny(notifier.onCreate)
-	handle.OnDeleteEventAny(notifier.onDelete)
+	// Register event handlers (only for enabled events).
+	f := cfg.Events
+	if f.EventEnabled("push") {
+		handle.OnPushEventAny(n.onPush)
+	}
+	if f.EventEnabled("issues") {
+		handle.OnIssuesEventAny(n.onIssue)
+	}
+	if f.EventEnabled("issue_comment") {
+		handle.OnIssueCommentEventAny(n.onIssueComment)
+	}
+	if f.EventEnabled("pull_request") {
+		handle.OnPullRequestEventAny(n.onPR)
+	}
+	if f.EventEnabled("pull_request_review") {
+		handle.OnPullRequestReviewEventAny(n.onPRReview)
+	}
+	if f.EventEnabled("pull_request_review_comment") {
+		handle.OnPullRequestReviewCommentEventAny(n.onPRReviewComment)
+	}
+	if f.EventEnabled("release") {
+		handle.OnReleaseEventAny(n.onRelease)
+	}
+	if f.EventEnabled("star") {
+		handle.OnStarEventAny(n.onStar)
+	}
+	if f.EventEnabled("fork") {
+		handle.OnForkEventAny(n.onFork)
+	}
+	if f.EventEnabled("workflow_run") {
+		handle.OnWorkflowRunEventAny(n.onWorkflowRun)
+	}
+	if f.EventEnabled("create") {
+		handle.OnCreateEventAny(n.onCreate)
+	}
+	if f.EventEnabled("delete") {
+		handle.OnDeleteEventAny(n.onDelete)
+	}
+
+	if f.IsEmpty() {
+		log.Println("event filter: all events enabled")
+	} else {
+		log.Printf("event filter: %v", f.rules)
+	}
 
 	handle.OnError(func(_ context.Context, _ string, _ string, _ interface{}, err error) error {
 		log.Printf("webhook error: %v", err)
@@ -75,6 +107,7 @@ type notifier struct {
 	signal    *signalcli.Client
 	recipient string
 	groupID   string
+	filter    EventFilter
 }
 
 func (n *notifier) send(ctx context.Context, msg string) {
@@ -94,61 +127,97 @@ func (n *notifier) send(ctx context.Context, msg string) {
 }
 
 func (n *notifier) onPush(ctx context.Context, _ string, _ string, event *github.PushEvent) error {
+	if !n.filter.Allowed("push", "") {
+		return nil
+	}
 	n.send(ctx, formatPush(event))
 	return nil
 }
 
 func (n *notifier) onIssue(ctx context.Context, _ string, _ string, event *github.IssuesEvent) error {
+	if !n.filter.Allowed("issues", event.GetAction()) {
+		return nil
+	}
 	n.send(ctx, formatIssue(event))
 	return nil
 }
 
 func (n *notifier) onIssueComment(ctx context.Context, _ string, _ string, event *github.IssueCommentEvent) error {
+	if !n.filter.Allowed("issue_comment", event.GetAction()) {
+		return nil
+	}
 	n.send(ctx, formatIssueComment(event))
 	return nil
 }
 
 func (n *notifier) onPR(ctx context.Context, _ string, _ string, event *github.PullRequestEvent) error {
+	if !n.filter.Allowed("pull_request", event.GetAction()) {
+		return nil
+	}
 	n.send(ctx, formatPR(event))
 	return nil
 }
 
 func (n *notifier) onPRReview(ctx context.Context, _ string, _ string, event *github.PullRequestReviewEvent) error {
+	if !n.filter.Allowed("pull_request_review", event.GetAction()) {
+		return nil
+	}
 	n.send(ctx, formatPRReview(event))
 	return nil
 }
 
 func (n *notifier) onPRReviewComment(ctx context.Context, _ string, _ string, event *github.PullRequestReviewCommentEvent) error {
+	if !n.filter.Allowed("pull_request_review_comment", event.GetAction()) {
+		return nil
+	}
 	n.send(ctx, formatPRReviewComment(event))
 	return nil
 }
 
 func (n *notifier) onRelease(ctx context.Context, _ string, _ string, event *github.ReleaseEvent) error {
+	if !n.filter.Allowed("release", event.GetAction()) {
+		return nil
+	}
 	n.send(ctx, formatRelease(event))
 	return nil
 }
 
 func (n *notifier) onStar(ctx context.Context, _ string, _ string, event *github.StarEvent) error {
+	if !n.filter.Allowed("star", event.GetAction()) {
+		return nil
+	}
 	n.send(ctx, formatStar(event))
 	return nil
 }
 
 func (n *notifier) onFork(ctx context.Context, _ string, _ string, event *github.ForkEvent) error {
+	if !n.filter.Allowed("fork", "") {
+		return nil
+	}
 	n.send(ctx, formatFork(event))
 	return nil
 }
 
 func (n *notifier) onWorkflowRun(ctx context.Context, _ string, _ string, event *github.WorkflowRunEvent) error {
+	if !n.filter.Allowed("workflow_run", event.GetAction()) {
+		return nil
+	}
 	n.send(ctx, formatWorkflowRun(event))
 	return nil
 }
 
 func (n *notifier) onCreate(ctx context.Context, _ string, _ string, event *github.CreateEvent) error {
+	if !n.filter.Allowed("create", "") {
+		return nil
+	}
 	n.send(ctx, formatCreate(event))
 	return nil
 }
 
 func (n *notifier) onDelete(ctx context.Context, _ string, _ string, event *github.DeleteEvent) error {
+	if !n.filter.Allowed("delete", "") {
+		return nil
+	}
 	n.send(ctx, formatDelete(event))
 	return nil
 }