Implement Twitter API fetching for twitterstats

* Create Oauth2 client configured for Twitter and create a HTTP client out of that
 * Fetch user stats for each of the users, parse out of JSON, and return stats as stats structs

modules/twitterstats/client.go

@@ -1,18 +1,31 @@
 package twitterstats
 
 import (
+	"encoding/json"
+	"fmt"
+	"io/ioutil"
 	"log"
+	"net/http"
+
+	"golang.org/x/oauth2"
+	"golang.org/x/oauth2/clientcredentials"
 )
 
 type Client struct {
 	apiBase     string
-	consumerKey       string
-	consumerSecret    string
-	accessToken       string
-	accessTokenSecret string
+	httpClient  *http.Client
 	screenNames []string
 }
 
+type TwitterStats struct {
+	followerCount int64
+	tweetCount    int64
+}
+
+const (
+	userTimelineUrl = "https://api.twitter.com/1.1/users/show.json"
+)
+
 func NewClient(settings *Settings) *Client {
 	usernames := make([]string, len(settings.screenNames))
 	for i, username := range settings.screenNames {
@@ -27,22 +40,55 @@ func NewClient(settings *Settings) *Client {
 
 	}
 
+	conf := &clientcredentials.Config{
+		ClientID:     settings.consumerKey,
+		ClientSecret: settings.consumerSecret,
+		TokenURL:     "https://api.twitter.com/oauth2/token",
+	}
+
+	// token, err := conf.Token(oauth2.NoContext)
+	httpClient := conf.Client(oauth2.NoContext)
+
 	client := Client{
 		apiBase:     "https://api.twitter.com/1.1/",
-		consumerKey:       settings.consumerKey,
-		consumerSecret:    settings.consumerSecret,
-		accessToken:       settings.accessToken,
-		accessTokenSecret: settings.accessTokenSecret,
+		httpClient:  httpClient,
 		screenNames: usernames,
 	}
 
 	return &client
 }
 
-func (client *Client) GetFollowerCounts() []int64 {
-	return []int64{0, 0, 0, 0, 0} // TODO
+func (client *Client) GetStats() []TwitterStats {
+	stats := make([]TwitterStats, len(client.screenNames))
+
+	for i, username := range client.screenNames {
+		stats[i] = TwitterStats{
+			followerCount: 0,
+			tweetCount:    0,
 		}
 
-func (client *Client) GetTweetCounts() []int64 {
-	return []int64{0, 0, 0, 0, 0} // TODO
+		res, err := client.httpClient.Get(fmt.Sprintf("%s?screen_name=%s", userTimelineUrl, username))
+		if err != nil {
+			continue
+		}
+		defer res.Body.Close()
+
+		body, err := ioutil.ReadAll(res.Body)
+		if err != nil {
+			continue
+		}
+
+		var parsed map[string]interface{}
+		err = json.Unmarshal(body, &parsed)
+		if err != nil {
+			continue
+		}
+
+		stats[i] = TwitterStats{
+			followerCount: int64(parsed["followers_count"].(float64)),
+			tweetCount:    int64(parsed["statuses_count"].(float64)),
+		}
+	}
+
+	return stats
 }

modules/twitterstats/widget.go

@@ -40,16 +40,15 @@ func (widget *Widget) Refresh() {
 
 func (widget *Widget) content() (string, string, bool) {
 	usernames := widget.client.screenNames
-	followerCounts := widget.client.GetFollowerCounts()
-	tweetCounts := widget.client.GetTweetCounts()
+	stats := widget.client.GetStats()
 
 	// Add header row
 	str := fmt.Sprintf("%-16s %-8s %-8s\n", "Username", "Followers", "# Tweets")
 
 	// Add rows for each of the followed usernames
 	for i, username := range usernames {
-		followerCount := followerCounts[i]
-		tweetCount := tweetCounts[i]
+		followerCount := stats[i].followerCount
+		tweetCount := stats[i].tweetCount
 
 		str += fmt.Sprintf("%-16s %8d %8d\n", username, followerCount, tweetCount)
 	}