Added min and max supported interval

extension/solarwindsapmsettingsextension/README.md

@@ -34,4 +34,10 @@ The service key in format `<token>:<name>` for `getSettings` from Solarwinds APM
 ### interval (Optional)
 Periodic interval to get Solarwinds APM specific settings from Solarwinds APM collector.
 
+Minimum value: `5s`
+
+Maximum value: `60s`
+
+Value that is outside the boundary will be bounded to either the minimum or maximum value.
+
 Default: `10s`

extension/solarwindsapmsettingsextension/config_test.go

@@ -49,6 +49,15 @@ func TestValidate(t *testing.T) {
 			},
 			err: errors.New("key should be in \"<token>:<service_name>\" format"),
 		},
+		{
+			name: "valid",
+			cfg: &Config{
+				Endpoint: "host:12345",
+				Key:      "token:name",
+				Interval: "1s",
+			},
+			err: nil,
+		},
 	}
 	for _, tc := range tests {
 		t.Run(tc.name, func(t *testing.T) {

extension/solarwindsapmsettingsextension/extension.go

@@ -21,8 +21,10 @@ import (
 )
 
 const (
-	RawOutputFile  = "/tmp/solarwinds-apm-settings-raw"
-	JSONOutputFile = "/tmp/solarwinds-apm-settings.json"
+	RawOutputFile   = "/tmp/solarwinds-apm-settings-raw"
+	JSONOutputFile  = "/tmp/solarwinds-apm-settings.json"
+	MinimumInterval = "5s"
+	MaximumInterval = "60s"
 )
 
 type solarwindsapmSettingsExtension struct {
@@ -195,7 +197,18 @@ func (extension *solarwindsapmSettingsExtension) Start(ctx context.Context, _ co
 
 	// setup lightweight thread to refresh
 	var interval time.Duration
-	interval, err = time.ParseDuration(extension.config.Interval)
+	interval, _ = time.ParseDuration(extension.config.Interval)
+	minimum, _ := time.ParseDuration(MinimumInterval)
+	maximum, _ := time.ParseDuration(MaximumInterval)
+	if interval.Seconds() < minimum.Seconds() {
+		interval = minimum
+		extension.logger.Warn("Interval " + extension.config.Interval + " is bounded to the minimum interval " + MinimumInterval)
+	}
+	if interval.Seconds() > maximum.Seconds() {
+		interval = maximum
+		extension.logger.Warn("Interval " + extension.config.Interval + " is bounded to the maximum interval " + MaximumInterval)
+	}
+
 	go func() {
 		ticker := time.NewTicker(interval)
 		defer ticker.Stop()

extension/solarwindsapmsettingsextension/extension_test.go

@@ -12,7 +12,7 @@ func TestCreateExtension(t *testing.T) {
 	conf := &Config{
 		Endpoint: "apm-testcollector.click:443",
 		Key:      "valid:unittest",
-		Interval: "1s",
+		Interval: "10s",
 	}
 	ex := createAnExtension(conf, t)
 	ex.Shutdown(context.TODO())
@@ -22,7 +22,7 @@ func TestCreateExtensionWrongEndpoint(t *testing.T) {
 	conf := &Config{
 		Endpoint: "apm-testcollector.nothing:443",
 		Key:      "valid:unittest",
-		Interval: "1s",
+		Interval: "5s",
 	}
 	ex := createAnExtension(conf, t)
 	ex.Shutdown(context.TODO())
@@ -32,7 +32,27 @@ func TestCreateExtensionWrongKey(t *testing.T) {
 	conf := &Config{
 		Endpoint: "apm-testcollector.click:443",
 		Key:      "invalid",
-		Interval: "1s",
+		Interval: "60s",
+	}
+	ex := createAnExtension(conf, t)
+	ex.Shutdown(context.TODO())
+}
+
+func TestCreateExtensionIntervalLessThanMinimum(t *testing.T) {
+	conf := &Config{
+		Endpoint: "apm-testcollector.click:443",
+		Key:      "valid:unittest",
+		Interval: "4s",
+	}
+	ex := createAnExtension(conf, t)
+	ex.Shutdown(context.TODO())
+}
+
+func TestCreateExtensionIntervalGreaterThanMaximum(t *testing.T) {
+	conf := &Config{
+		Endpoint: "apm-testcollector.click:443",
+		Key:      "valid:unittest",
+		Interval: "61s",
 	}
 	ex := createAnExtension(conf, t)
 	ex.Shutdown(context.TODO())