Now use prometheus_retention_time > 0 to enable prometheus support

agent/agent_endpoint.go

@@ -89,6 +89,11 @@ func (s *HTTPServer) AgentMetrics(resp http.ResponseWriter, req *http.Request) (
 		return nil, acl.ErrPermissionDenied
 	}
 	if format := req.URL.Query().Get("format"); format == "prometheus" {
+		if s.agent.config.TelemetryPrometheusRetentionTime.Nanoseconds() < 1 {
+			resp.WriteHeader(http.StatusUnsupportedMediaType)
+			fmt.Fprint(resp, "Prometheus is not enable since its retention time is not positive")
+			return nil, nil
+		}
 		handlerOptions := promhttp.HandlerOpts{
 			ErrorLog:           s.agent.logger,
 			ErrorHandling:      promhttp.ContinueOnError,

agent/config/builder.go

@@ -626,7 +626,7 @@ func (b *Builder) Build() (rt RuntimeConfig, err error) {
 		TelemetryDisableHostname:                    b.boolVal(c.Telemetry.DisableHostname),
 		TelemetryDogstatsdAddr:                      b.stringVal(c.Telemetry.DogstatsdAddr),
 		TelemetryDogstatsdTags:                      c.Telemetry.DogstatsdTags,
-		TelemetryPrometheusDisable:                  b.boolVal(c.Telemetry.PrometheusDisable),
+		TelemetryPrometheusRetentionTime:            b.durationVal("prometheus_retention_time", c.Telemetry.PrometheusRetentionTime),
 		TelemetryFilterDefault:                      b.boolVal(c.Telemetry.FilterDefault),
 		TelemetryAllowedPrefixes:                    telemetryAllowedPrefixes,
 		TelemetryBlockedPrefixes:                    telemetryBlockedPrefixes,

agent/config/config.go

@@ -394,7 +394,7 @@ type Telemetry struct {
 	FilterDefault                      *bool    `json:"filter_default,omitempty" hcl:"filter_default" mapstructure:"filter_default"`
 	PrefixFilter                       []string `json:"prefix_filter,omitempty" hcl:"prefix_filter" mapstructure:"prefix_filter"`
 	MetricsPrefix                      *string  `json:"metrics_prefix,omitempty" hcl:"metrics_prefix" mapstructure:"metrics_prefix"`
-	PrometheusDisable                  *bool    `json:"prometheus_disable,omitempty" hcl:"prometheus_disable" mapstructure:"prometheus_disable"`
+	PrometheusRetentionTime            *string  `json:"prometheus_retention_time,omitempty" hcl:"prometheus_retention_time" mapstructure:"prometheus_retention_time"`
 	StatsdAddr                         *string  `json:"statsd_address,omitempty" hcl:"statsd_address" mapstructure:"statsd_address"`
 	StatsiteAddr                       *string  `json:"statsite_address,omitempty" hcl:"statsite_address" mapstructure:"statsite_address"`
 	EnableDeprecatedNames              *bool    `json:"enable_deprecated_names" hcl:"enable_deprecated_names" mapstructure:"enable_deprecated_names"`

agent/config/runtime.go

@@ -425,10 +425,10 @@ type RuntimeConfig struct {
 	// hcl: telemetry { dogstatsd_tags = []string }
 	TelemetryDogstatsdTags []string
 
-	// TelemetryPrometheusDisable enables prometheus Support for metrics
+	// PrometheusRetentionTime enables prometheus Support for metrics if greater than 0
 	//
-	// hcl: telemetry { prometheus_disable = (true|false) }
+	// hcl: telemetry { prometheus_retention_time = "duration" }
-	TelemetryPrometheusDisable bool
+	TelemetryPrometheusRetentionTime time.Duration
 
 	// TelemetryFilterDefault is the default for whether to allow a metric that's not
 	// covered by the filter.

agent/config/runtime_test.go

@@ -2589,7 +2589,7 @@ func TestFullConfig(t *testing.T) {
 				"prefix_filter": [ "+oJotS8XJ","-cazlEhGn" ],
 				"enable_deprecated_names": true,
 				"metrics_prefix": "ftO6DySn",
-				"prometheus_disable": true,
+				"prometheus_retention_time": "15s",
 				"statsd_address": "drce87cy",
 				"statsite_address": "HpFwKB8R"
 			},
@@ -3027,7 +3027,7 @@ func TestFullConfig(t *testing.T) {
 				prefix_filter = [ "+oJotS8XJ","-cazlEhGn" ]
 				enable_deprecated_names = true
 				metrics_prefix = "ftO6DySn"
-				prometheus_disable = true
+				prometheus_retention_time = "15s"
 				statsd_address = "drce87cy"
 				statsite_address = "HpFwKB8R"
 			}
@@ -3590,7 +3590,7 @@ func TestFullConfig(t *testing.T) {
 		TelemetryAllowedPrefixes:                    []string{"oJotS8XJ", "consul.consul"},
 		TelemetryBlockedPrefixes:                    []string{"cazlEhGn"},
 		TelemetryMetricsPrefix:                      "ftO6DySn",
-		TelemetryPrometheusDisable:                  true,
+		TelemetryPrometheusRetentionTime:            15 * time.Second,
 		TelemetryStatsdAddr:                         "drce87cy",
 		TelemetryStatsiteAddr:                       "HpFwKB8R",
 		TLSCipherSuites:                             []uint16{tls.TLS_ECDHE_RSA_WITH_CHACHA20_POLY1305, tls.TLS_ECDHE_ECDSA_WITH_AES_256_GCM_SHA384},
@@ -4143,7 +4143,7 @@ func TestSanitize(t *testing.T) {
     "TelemetryDogstatsdTags": [],
     "TelemetryFilterDefault": false,
     "TelemetryMetricsPrefix": "",
-    "TelemetryPrometheusDisable": false,
+    "TelemetryPrometheusRetentionTime": "0s",
     "TelemetryStatsdAddr": "",
     "TelemetryStatsiteAddr": "",
     "TranslateWANAddrs": false,

command/agent/agent.go

@@ -210,10 +210,13 @@ func dogstatdSink(config *config.RuntimeConfig, hostname string) (metrics.Metric
 }
 
 func prometheusSink(config *config.RuntimeConfig, hostname string) (metrics.MetricSink, error) {
-	if config.TelemetryPrometheusDisable {
+	if config.TelemetryPrometheusRetentionTime.Nanoseconds() < 1 {
 		return nil, nil
 	}
-	sink, err := prometheus.NewPrometheusSink()
+	prometheusOpts := prometheus.PrometheusOpts{
+		Expiration: config.TelemetryPrometheusRetentionTime,
+	}
+	sink, err := prometheus.NewPrometheusSinkFrom(prometheusOpts)
 	if err != nil {
 		return nil, err
 	}