Changes Accept header function of api version used.

  - v1: `application/openmetrics-text; version=0.0.1,text/plain;version=0.0.4;q=0.5,*/*;q=0.1`
  - v2: `text/plain; version=0.0.4; charset=utf-8`

api/metrics.go

@@ -7,23 +7,12 @@ import (
 	"strings"
 
 	"github.com/gorilla/mux"
-	"github.com/orange-cloudfoundry/promfetcher/models"
 	"github.com/prometheus/common/expfmt"
 
 	"github.com/orange-cloudfoundry/promfetcher/errors"
 )
 
 func (a Api) metrics(w http.ResponseWriter, req *http.Request) {
-	// extract the API version from the requested path (ie: /v2)
-	// and set it to an HTTP header
-	apiVersion := regexp.MustCompile("/v([0-9]+)(?:/|$)").FindStringSubmatch(req.URL.Path)
-	if len(apiVersion) == 2 {
-		req.Header.Set(models.XPromfetcherApiVersion, apiVersion[1])
-	} else {
-		// default to v1
-		req.Header.Set(models.XPromfetcherApiVersion, "1")
-	}
-
 	appIdOrPathOrName, ok := mux.Vars(req)["appIdOrPathOrName"]
 	if !ok {
 		appIdOrPathOrName = req.URL.Query().Get("app")
@@ -47,6 +36,15 @@ func (a Api) metrics(w http.ResponseWriter, req *http.Request) {
 	_, onlyAppMetrics := req.URL.Query()["only_from_app"]
 
 	headersMetrics := make(http.Header)
+	// extract the API version from the requested path (ie: /v2)
+	// and set it to an HTTP header
+	apiVersion := regexp.MustCompile("/v([0-9]+)(?:/|$)").FindStringSubmatch(req.URL.Path)
+	if len(apiVersion) == 2 && apiVersion[1] != "1" {
+		headersMetrics.Set("Accept", string(expfmt.FmtText))
+	} else {
+		headersMetrics.Set("Accept", `application/openmetrics-text; version=0.0.1,text/plain;version=0.0.4;q=0.5,*/*;q=0.1`)
+	}
+
 	auth := req.Header.Get("Authorization")
 	if auth != "" {
 		headersMetrics.Set("Authorization", auth)

scrapers/scrape.go

@@ -12,7 +12,6 @@ import (
 	"github.com/orange-cloudfoundry/promfetcher/clients"
 	"github.com/orange-cloudfoundry/promfetcher/errors"
 	"github.com/orange-cloudfoundry/promfetcher/models"
-	"github.com/prometheus/common/expfmt"
 )
 
 type Scraper struct {
@@ -68,14 +67,6 @@ func (s Scraper) Scrape(route *models.Route, metricPathDefault string, headers h
 			req.Header[k] = v
 		}
 	}
-	// Prometheus parser is not OpenMetrics compliant
-	// See: prometheus/common issues: 214, 829
-	req.Header.Set("Accept", string(expfmt.FmtText))
-	// keep the OpenMetrics accept HTTP header for the /v1 endpoint
-	if req.Header.Get(models.XPromfetcherApiVersion) == "1" {
-		req.Header.Set(models.XPromfetcherApiVersion, "1")
-		req.Header.Set("Accept", `application/openmetrics-text; version=0.0.1,text/plain;version=0.0.4;q=0.5,*/*;q=0.1`)
-	}
 	req.Header.Add("Accept-Encoding", "gzip")
 	req.Header.Set("X-Prometheus-Scrape-Timeout-Seconds", fmt.Sprintf("%f", (30*time.Second).Seconds()))
 	req.Header.Set("X-Forwarded-Proto", scheme)