[exporter/signalfx] fix invalid error response message (#12654)

Fixing a bug - The signalfx exporter discards metric submission response messages and thus provides invalid error content

exporter/signalfxexporter/dpclient.go

@@ -138,8 +138,10 @@ func (s *sfxDPClient) pushMetricsDataForToken(ctx context.Context, sfxDataPoints
 		return len(sfxDataPoints), err
 	}
 
-	io.Copy(ioutil.Discard, resp.Body)
-	resp.Body.Close()
+	defer func() {
+		io.Copy(ioutil.Discard, resp.Body)
+		resp.Body.Close()
+	}()
 
 	err = splunk.HandleHTTPCode(resp)
 	if err != nil {

exporter/signalfxexporter/exporter_test.go

@@ -140,6 +140,7 @@ func TestConsumeMetrics(t *testing.T) {
 		wantErr              bool
 		wantPermanentErr     bool
 		wantThrottleErr      bool
+		expectedErrorMsg     string
 	}{
 		{
 			name:             "happy_path",
@@ -152,13 +153,15 @@ func TestConsumeMetrics(t *testing.T) {
 			httpResponseCode:     http.StatusForbidden,
 			numDroppedTimeSeries: 1,
 			wantErr:              true,
+			expectedErrorMsg:     "HTTP 403 \"Forbidden\"",
 		},
 		{
 			name:                 "response_bad_request",
 			md:                   smallBatch,
 			httpResponseCode:     http.StatusBadRequest,
 			numDroppedTimeSeries: 1,
 			wantPermanentErr:     true,
+			expectedErrorMsg:     "Permanent error: \"HTTP/1.1 400 Bad Request",
 		},
 		{
 			name:                 "response_throttle",
@@ -190,6 +193,7 @@ func TestConsumeMetrics(t *testing.T) {
 					w.Header().Add(splunk.HeaderRetryAfter, strconv.Itoa(tt.retryAfter))
 				}
 				w.WriteHeader(tt.httpResponseCode)
+				w.Write([]byte("response content"))
 			}))
 			defer server.Close()
 
@@ -219,12 +223,15 @@ func TestConsumeMetrics(t *testing.T) {
 
 			if tt.wantErr {
 				assert.Error(t, err)
+				assert.EqualError(t, err, tt.expectedErrorMsg)
 				return
 			}
 
 			if tt.wantPermanentErr {
 				assert.Error(t, err)
 				assert.True(t, consumererror.IsPermanent(err))
+				assert.True(t, strings.HasPrefix(err.Error(), tt.expectedErrorMsg))
+				assert.Contains(t, err.Error(), "response content")
 				return
 			}
 

unreleased/sfxexportearlyrespclose.yaml

@@ -0,0 +1,5 @@
+change_type: bug_fix
+component: signalfxexporter
+note: fix invalid response error message
+issues: [12654]
+