fix(find): return error on partial failure of metrics find

cmd/carbonapi/http/find_handlers.go

@@ -23,6 +23,7 @@ import (
 	"github.com/go-graphite/carbonapi/date"
 	"github.com/go-graphite/carbonapi/intervalset"
 	utilctx "github.com/go-graphite/carbonapi/util/ctx"
+	"github.com/go-graphite/carbonapi/zipper/helper"
 )
 
 // Find handler and it's helper functions
@@ -175,6 +176,7 @@ func findList(multiGlobs *pbv3.MultiGlobResponse) ([]byte, error) {
 func findHandler(w http.ResponseWriter, r *http.Request) {
 	t0 := time.Now()
 	uid := uuid.NewV4()
+	carbonapiUUID := uid.String()
 	// TODO: Migrate to context.WithTimeout
 	// ctx, _ := context.WithTimeout(context.TODO(), config.Config.ZipperTimeout)
 	ctx := utilctx.SetUUID(r.Context(), uid.String())
@@ -197,7 +199,7 @@ func findHandler(w http.ResponseWriter, r *http.Request) {
 	var accessLogDetails = carbonapipb.AccessLogDetails{
 		Handler:        "find",
 		Username:       username,
-		CarbonapiUUID:  uid.String(),
+		CarbonapiUUID:  carbonapiUUID,
 		URL:            r.URL.RequestURI(),
 		PeerIP:         srcIP,
 		PeerPort:       srcPort,
@@ -214,10 +216,10 @@ func findHandler(w http.ResponseWriter, r *http.Request) {
 	}()
 
 	if !ok || !format.ValidFindFormat() {
-		http.Error(w, "unsupported format: "+formatRaw, http.StatusBadRequest)
 		accessLogDetails.HTTPCode = http.StatusBadRequest
 		accessLogDetails.Reason = "unsupported format: " + formatRaw
 		logAsError = true
+		writeErrorResponse(w, int(accessLogDetails.HTTPCode), accessLogDetails.Reason, carbonapiUUID)
 		return
 	}
 
@@ -240,15 +242,15 @@ func findHandler(w http.ResponseWriter, r *http.Request) {
 		if err != nil {
 			accessLogDetails.HTTPCode = http.StatusBadRequest
 			accessLogDetails.Reason = "failed to parse message body: " + err.Error()
-			http.Error(w, "bad request (failed to parse format): "+err.Error(), http.StatusBadRequest)
+			writeErrorResponse(w, http.StatusBadRequest, accessLogDetails.Reason, carbonapiUUID)
 			return
 		}
 
 		err = pv3Request.Unmarshal(body)
 		if err != nil {
 			accessLogDetails.HTTPCode = http.StatusBadRequest
 			accessLogDetails.Reason = "failed to parse message body: " + err.Error()
-			http.Error(w, "bad request (failed to parse format): "+err.Error(), http.StatusBadRequest)
+			writeErrorResponse(w, http.StatusBadRequest, accessLogDetails.Reason, carbonapiUUID)
 			return
 		}
 	} else {
@@ -258,10 +260,10 @@ func findHandler(w http.ResponseWriter, r *http.Request) {
 	}
 
 	if len(pv3Request.Metrics) == 0 {
-		http.Error(w, "missing parameter `query`", http.StatusBadRequest)
 		accessLogDetails.HTTPCode = http.StatusBadRequest
 		accessLogDetails.Reason = "missing parameter `query`"
 		logAsError = true
+		writeErrorResponse(w, http.StatusBadRequest, accessLogDetails.Reason, carbonapiUUID)
 		return
 	}
 
@@ -273,7 +275,7 @@ func findHandler(w http.ResponseWriter, r *http.Request) {
 		accessLogDetails.TotalMetricsCount += stats.TotalMetricsCount
 	}
 	if err != nil {
-		returnCode := merry.HTTPCode(err)
+		returnCode := merry.HTTPCode(helper.HttpErrorByCode(err))
 		if returnCode != http.StatusOK || multiGlobs == nil {
 			// Allow override status code for 404-not-found replies.
 			if returnCode == http.StatusNotFound {
@@ -283,9 +285,9 @@ func findHandler(w http.ResponseWriter, r *http.Request) {
 			if returnCode < 300 {
 				multiGlobs = &pbv3.MultiGlobResponse{Metrics: []pbv3.GlobResponse{}}
 			} else {
-				http.Error(w, http.StatusText(returnCode), returnCode)
 				accessLogDetails.HTTPCode = int32(returnCode)
 				accessLogDetails.Reason = err.Error()
+				writeErrorResponse(w, returnCode, accessLogDetails.Reason, carbonapiUUID)
 				// We don't want to log this as an error if it's something normal
 				// Normal is everything that is >= 500. So if config.Config.NotFoundStatusCode is 500 - this will be
 				// logged as error
@@ -365,12 +367,12 @@ func findHandler(w http.ResponseWriter, r *http.Request) {
 	}
 
 	if err != nil {
-		http.Error(w, http.StatusText(http.StatusInternalServerError), http.StatusInternalServerError)
 		accessLogDetails.HTTPCode = http.StatusInternalServerError
 		accessLogDetails.Reason = err.Error()
 		logAsError = true
+		writeErrorResponse(w, http.StatusInternalServerError, accessLogDetails.Reason, carbonapiUUID)
 		return
 	}
 
-	writeResponse(w, http.StatusOK, b, format, jsonp, uid.String())
+	writeResponse(w, http.StatusOK, b, format, jsonp, carbonapiUUID)
 }

cmd/carbonapi/http/helper.go

@@ -158,6 +158,11 @@ func getFormat(r *http.Request, defaultFormat responseFormat) (responseFormat, b
 	return f, ok, format
 }
 
+func writeErrorResponse(w http.ResponseWriter, returnCode int, err, carbonapiUUID string) {
+	w.Header().Set(ctxHeaderUUID, carbonapiUUID)
+	http.Error(w, err, returnCode)
+}
+
 func writeResponse(w http.ResponseWriter, returnCode int, b []byte, format responseFormat, jsonp, carbonapiUUID string) {
 	//TODO: Simplify that switch
 	w.Header().Set(ctxHeaderUUID, carbonapiUUID)