(FFM-5314) Optionally poll targets

cmd/ff-proxy/main.go

@@ -185,7 +185,7 @@ func init() {
 	flag.StringVar(&redisPassword, redisPasswordFlag, "", "Optional. Redis password")
 	flag.IntVar(&redisDB, redisDBFlag, 0, "Database to be selected after connecting to the server.")
 	flag.Var(&apiKeys, apiKeysFlag, "API keys to connect with ff-server for each environment")
-	flag.IntVar(&targetPollDuration, targetPollDurationFlag, 60, "How often in seconds the proxy polls feature flags for Target changes")
+	flag.IntVar(&targetPollDuration, targetPollDurationFlag, 60, "How often in seconds the proxy polls feature flags for Target changes. Set to 0 to disable.")
 	flag.IntVar(&metricPostDuration, metricPostDurationFlag, 60, "How often in seconds the proxy posts metrics to Harness. Set to 0 to disable.")
 	flag.IntVar(&heartbeatInterval, heartbeatIntervalFlag, 60, "How often in seconds the proxy polls pings it's health function")
 	flag.BoolVar(&pprofEnabled, pprofEnabledFlag, false, "enables pprof on port 6060")
@@ -388,6 +388,7 @@ func main() {
 			adminService,
 			config.WithLogger(logger),
 			config.WithConcurrency(20),
+			config.WithFetchTargets(targetPollDuration != 0), // don't fetch targets if poll duration is 0
 		)
 		if err != nil {
 			logger.Error("error(s) encountered fetching config from FeatureFlags, startup will continue but the Proxy may be missing required config", "errors", err)
@@ -514,17 +515,20 @@ func main() {
 
 	if !offline {
 		// start target polling ticker
-		go func() {
-			ticker := time.NewTicker(time.Duration(targetPollDuration) * time.Second)
-			defer ticker.Stop()
+		// don't poll for targets if duration is 0
+		if targetPollDuration != 0 {
+			go func() {
+				ticker := time.NewTicker(time.Duration(targetPollDuration) * time.Second)
+				defer ticker.Stop()
 
-			logger.Info(fmt.Sprintf("polling for new targets every %d seconds", targetPollDuration))
-			for targetConfig := range remoteConfig.PollTargets(ctx, ticker.C) {
-				for key, values := range targetConfig {
-					tr.DeltaAdd(ctx, key, values...)
+				logger.Info(fmt.Sprintf("polling for new targets every %d seconds", targetPollDuration))
+				for targetConfig := range remoteConfig.PollTargets(ctx, ticker.C) {
+					for key, values := range targetConfig {
+						tr.DeltaAdd(ctx, key, values...)
+					}
 				}
-			}
-		}()
+			}()
+		}
 
 		// start metric sending ticker
 		if metricPostDuration != 0 {

config/remote_config.go

@@ -31,6 +31,13 @@ func WithLogger(l log.Logger) RemoteOption {
 	}
 }
 
+// WithFetchTargets specifies if the RemoteConfig instance should fetch targets or not
+func WithFetchTargets(fetchTargets bool) RemoteOption {
+	return func(r *RemoteConfig) {
+		r.fetchTargets = fetchTargets
+	}
+}
+
 type adminClient interface {
 	PageProjects(ctx context.Context, input services.PageProjectsInput) (services.PageProjectsResult, error)
 	PageTargets(ctx context.Context, input services.PageTargetsInput) (services.PageTargetsResult, error)
@@ -50,7 +57,8 @@ type RemoteConfig struct {
 	// we store project and environment info after the initial load so that the
 	// PollTargets functioncan use it and not have to make GetProjects and
 	// GetEnvironments requests every time
-	projEnvInfo map[string]configPipeline
+	projEnvInfo  map[string]configPipeline
+	fetchTargets bool
 }
 
 // NewRemoteConfig creates a RemoteConfig and retrieves the configuration for
@@ -68,6 +76,7 @@ func NewRemoteConfig(ctx context.Context, accountIdentifer string, orgIdentifier
 		accountIdentifer: accountIdentifer,
 		orgIdentifier:    orgIdentifier,
 		allowedAPIKeys:   allowedAPIKeys,
+		fetchTargets:     true,
 	}
 
 	for _, opt := range opts {
@@ -446,6 +455,11 @@ func (r RemoteConfig) addTargetConfig(ctx context.Context, inputs <-chan configP
 		defer close(out)
 
 		for input := range inputs {
+			// if we don't watch to fetch targets just skip
+			if !r.fetchTargets {
+				sendOrDone(ctx, out, input)
+				continue
+			}
 			// If an earlier stage in the pipeline has failed there's no point
 			// trying to execute this stage. We still pass the event on so the
 			// caller can get the original error

docs/configuration.md

@@ -75,12 +75,11 @@ Some corporate networks may be highly restrictive on allowing sse connections. I
 ### Adjust timings
 Adjust how often certain actions are performed.
 
-| Environment Variable | Flag                 | Description                                                                                                                                                                                                                          | Type    | Default |
-|----------------------|----------------------|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|---------|---------|
-| TARGET_POLL_DURATION | target-poll-duration | How often in seconds the proxy polls feature flags for Target changes                                                                                                                                                                | int     | 60      |
-| METRIC_POST_DURATION | metric-post-duration | How often in seconds the proxy posts metrics to Harness. Set to 0 to disable.                                                                                                                                                        | int     | 60      |
-| HEARTBEAT_INTERVAL   | heartbeat-interval   | How often in seconds the proxy polls pings it's health function                                                                                                                                                                      | int     | 60      |
-
+| Environment Variable | Flag                 | Description                                                                                 | Type | Default |
+|----------------------|----------------------|---------------------------------------------------------------------------------------------|------|---------|
+| TARGET_POLL_DURATION | target-poll-duration | How often in seconds the proxy polls feature flags for Target changes. Set to 0 to disable. | int  | 60      |
+| METRIC_POST_DURATION | metric-post-duration | How often in seconds the proxy posts metrics to Harness. Set to 0 to disable.               | int  | 60      |
+| HEARTBEAT_INTERVAL   | heartbeat-interval   | How often in seconds the proxy polls pings it's health function                             | int  | 60      |
 
 ### Harness URLs
 You may need to adjust these if you pass all your traffic through a filter or proxy rather than sending the requests directly. 

tests/e2e/testhelpers/setup/main.go

@@ -44,7 +44,8 @@ ADMIN_SERVICE_TOKEN=%s
 API_KEYS=%s
 AUTH_SECRET=my_secret
 REDIS_ADDRESS=redis:6379
-PORT=9000`
+PORT=9000
+TARGET_POLL_DURATION=0`
 
 var generateOfflineConfigTemplate = `ACCOUNT_IDENTIFIER=%s
 ORG_IDENTIFIER=%s