Adds support to configure retry on Rate-Limiting from remote-write config.

Signed-off-by: Harkishen-Singh <harkishensingh@hotmail.com>

config/config.go

@@ -653,6 +653,7 @@ type QueueConfig struct {
 	// On recoverable errors, backoff exponentially.
 	MinBackoff       model.Duration `yaml:"min_backoff,omitempty"`
 	MaxBackoff       model.Duration `yaml:"max_backoff,omitempty"`
+	RetryOnRateLimit bool           `yaml:"retry_on_http_429,omitempty"`
 }
 
 // MetadataConfig is the configuration for sending metadata to remote

config/config_test.go

@@ -734,6 +734,20 @@ func TestYAMLRoundtrip(t *testing.T) {
 	require.Equal(t, want, got)
 }
 
+func TestRemoteWriteRetryOnRateLimit(t *testing.T) {
+	want, err := LoadFile("testdata/remote_write_retry_on_rate_limit.good.yml")
+	require.NoError(t, err)
+
+	out, err := yaml.Marshal(want)
+
+	require.NoError(t, err)
+	got := &Config{}
+	require.NoError(t, yaml.UnmarshalStrict(out, got))
+
+	require.Equal(t, true, got.RemoteWriteConfigs[0].QueueConfig.RetryOnRateLimit)
+	require.Equal(t, false, got.RemoteWriteConfigs[1].QueueConfig.RetryOnRateLimit)
+}
+
 func TestLoadConfig(t *testing.T) {
 	// Parse a valid file that sets a global scrape timeout. This tests whether parsing
 	// an overwritten default field in the global config permanently changes the default.

config/testdata/remote_write_retry_on_rate_limit.good.yml

@@ -0,0 +1,5 @@
+remote_write:
+  - url: localhost:9090
+    queue_config:
+      retry_on_http_429: true
+  - url: localhost:9201

docs/configuration/configuration.md

@@ -1775,6 +1775,9 @@ queue_config:
   [ min_backoff: <duration> | default = 30ms ]
   # Maximum retry delay.
   [ max_backoff: <duration> | default = 100ms ]
+  # Retry upon receiving a 429 status code from the remote-write storage.
+  # This is experimental and might change in the future.
+  [ retry_on_http_429: <boolean> | default = false ]
 
 # Configures the sending of series metadata to remote storage.
 # Metadata configuration is subject to change at any point

storage/remote/client.go

@@ -85,6 +85,8 @@ type Client struct {
 	timeout    time.Duration
 	headers    map[string]string
 
+	retryOnRateLimit bool
+
 	readQueries         prometheus.Gauge
 	readQueriesTotal    *prometheus.CounterVec
 	readQueriesDuration prometheus.Observer
@@ -96,6 +98,7 @@ type ClientConfig struct {
 	Timeout          model.Duration
 	HTTPClientConfig config_util.HTTPClientConfig
 	Headers          map[string]string
+	RetryOnRateLimit bool
 }
 
 // ReadClient uses the SAMPLES method of remote read to read series samples from remote server.
@@ -143,6 +146,7 @@ func NewWriteClient(name string, conf *ClientConfig) (WriteClient, error) {
 		remoteName:       name,
 		url:              conf.URL,
 		Client:           httpClient,
+		retryOnRateLimit: conf.RetryOnRateLimit,
 		timeout:          time.Duration(conf.Timeout),
 		headers:          conf.Headers,
 	}, nil
@@ -209,7 +213,7 @@ func (c *Client) Store(ctx context.Context, req []byte) error {
 	if httpResp.StatusCode/100 == 5 {
 		return RecoverableError{err, defaultBackoff}
 	}
-	if httpResp.StatusCode == http.StatusTooManyRequests {
+	if c.retryOnRateLimit && httpResp.StatusCode == http.StatusTooManyRequests {
 		return RecoverableError{err, retryAfterDuration(httpResp.Header.Get("Retry-After"))}
 	}
 	return err

storage/remote/client_test.go

@@ -84,6 +84,50 @@ func TestStoreHTTPErrorHandling(t *testing.T) {
 	}
 }
 
+func TestClientRetryAfter(t *testing.T) {
+	server := httptest.NewServer(
+		http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+			http.Error(w, longErrMessage, 429)
+		}),
+	)
+	defer server.Close()
+
+	getClient := func(conf *ClientConfig) WriteClient {
+		hash, err := toHash(conf)
+		require.NoError(t, err)
+		c, err := NewWriteClient(hash, conf)
+		require.NoError(t, err)
+		return c
+	}
+
+	serverURL, err := url.Parse(server.URL)
+	require.NoError(t, err)
+
+	conf := &ClientConfig{
+		URL:              &config_util.URL{URL: serverURL},
+		Timeout:          model.Duration(time.Second),
+		RetryOnRateLimit: false,
+	}
+
+	c := getClient(conf)
+	err = c.Store(context.Background(), []byte{})
+	if _, ok := err.(RecoverableError); ok {
+		t.Fatal("recoverable error not expected")
+	}
+
+	conf = &ClientConfig{
+		URL:              &config_util.URL{URL: serverURL},
+		Timeout:          model.Duration(time.Second),
+		RetryOnRateLimit: true,
+	}
+
+	c = getClient(conf)
+	err = c.Store(context.Background(), []byte{})
+	if _, ok := err.(RecoverableError); !ok {
+		t.Fatal("recoverable error was expected")
+	}
+}
+
 func TestRetryAfterDuration(t *testing.T) {
 	tc := []struct {
 		name     string

storage/remote/write.go

@@ -135,6 +135,7 @@ func (rws *WriteStorage) ApplyConfig(conf *config.Config) error {
 			Timeout:          rwConf.RemoteTimeout,
 			HTTPClientConfig: rwConf.HTTPClientConfig,
 			Headers:          rwConf.Headers,
+			RetryOnRateLimit: rwConf.QueueConfig.RetryOnRateLimit,
 		})
 		if err != nil {
 			return err