initial prototype for metrics

router/middleware/stats/metrics.go

@@ -0,0 +1,91 @@
+package stats
+
+import (
+	"bytes"
+	"encoding/json"
+	"fmt"
+	"net/http"
+	"os"
+	"sync"
+	"time"
+
+	"github.com/gin-gonic/gin"
+
+	"github.com/drone/drone/router/middleware/location"
+	"github.com/drone/drone/store"
+)
+
+var once sync.Once
+
+var key string
+
+// Schedule is a middleware function that triggers
+// usage statistics.
+func Schedule(c *gin.Context) {
+	once.Do(func() {
+		go schedule(c.Copy())
+	})
+	c.Next()
+}
+
+func schedule(c *gin.Context) {
+	for {
+		send(c)
+		select {
+		case <-time.After(time.Hour * 24):
+		}
+	}
+}
+
+func send(c *gin.Context) {
+	defer recover()
+
+	// disable statistics for local hosting and test environments
+	host := location.Hostname(c)
+	switch host {
+	case "locahost", "127.0.0.1":
+		return
+	}
+
+	// disable statistics if no key provided
+	if len(key) == 0 {
+		return // skip
+	}
+
+	// disable statistics if environment variable specified
+	if os.Getenv("DISABLE_METRICS") != "" {
+		return // skip
+	}
+
+	in := struct {
+		Version string
+		Host    string
+		Config  struct {
+			Database string
+			Remote   string
+		}
+		Stats struct {
+			Users int
+			Repos int
+			Nodes int
+		}
+	}{}
+
+	var (
+		remote_, _   = c.Get("remote")
+		database_, _ = c.Get("database")
+		version, _   = c.Get("version")
+	)
+
+	in.Version = version.(string)
+	in.Config.Database = database_.(fmt.Stringer).String()
+	in.Config.Remote = remote_.(fmt.Stringer).String()
+	in.Stats.Users, _ = store.CountUsers(c)
+	in.Stats.Nodes, _ = store.CountNodes(c)
+	in.Stats.Repos, _ = store.CountRepos(c)
+
+	buf := new(bytes.Buffer)
+	json.NewEncoder(buf).Encode(&in)
+
+	http.Post("https://stats.drone.io", "application/json", buf)
+}