introducing requestID to http stack

httpd/filters.go

@@ -8,6 +8,8 @@ import (
 	"strings"
 	"time"
 
+	"code.google.com/p/go-uuid/uuid"
+
 	"github.com/influxdb/influxdb"
 )
 
@@ -111,6 +113,16 @@ func cors(inner http.Handler) http.Handler {
 	})
 }
 
+func requestID(inner http.Handler) http.Handler {
+	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		uid := uuid.NewUUID()
+		r.Header.Set("Request-Id", uid.String())
+		w.Header().Set("Request-Id", r.Header.Get("Request-Id"))
+
+		inner.ServeHTTP(w, r)
+	})
+}
+
 func logging(inner http.Handler, name string, weblog *log.Logger) http.Handler {
 	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
 		start := time.Now()

httpd/handler.go

@@ -85,6 +85,7 @@ func NewHandler(s *influxdb.Server, requireAuthentication bool) *Handler {
 		handler = r.handlerFunc
 		handler = authorize(handler, h, requireAuthentication)
 		handler = cors(handler)
+		handler = requestID(handler)
 		handler = logging(handler, r.name, weblog)
 		handler = recovery(handler, r.name, weblog) // make sure recovery is always last
 

httpd/response_logger.go

@@ -50,7 +50,8 @@ func (l *responseLogger) Size() int {
 
 // Common Log Format: http://en.wikipedia.org/wiki/Common_Log_Format
 
-// buildLogLine creates a common log format, plus referrer and user agent at the end
+// buildLogLine creates a common log format
+// in addittion to the common fields, we also append referrer, user agent and request ID
 func buildLogLine(l *responseLogger, r *http.Request, start time.Time) string {
 	username := "-"
 	url := r.URL
@@ -68,7 +69,7 @@ func buildLogLine(l *responseLogger, r *http.Request, start time.Time) string {
 
 	uri := url.RequestURI()
 	return fmt.Sprintf(
-		"%s %s %s %s %s %s %s %d %d %s %s",
+		"%s %s %s %s %s %s %s %d %d %s %s %s",
 		host,
 		"-",
 		username,
@@ -80,5 +81,6 @@ func buildLogLine(l *responseLogger, r *http.Request, start time.Time) string {
 		l.Size(),
 		r.Referer(),
 		r.UserAgent(),
+		r.Header.Get("Request-Id"),
 	)
 }