throw error if selectors not provided

Author: Eskibear

src/AzureAppConfigurationImpl.ts

@@ -159,7 +159,7 @@ export class AzureAppConfigurationImpl implements AzureAppConfiguration {
         const loadedSettings: ConfigurationSetting[] = [];
 
         // validate selectors
-        const selectors = getValidSelectors(this.#options?.selectors);
+        const selectors = getValidKeyValueSelectors(this.#options?.selectors);
 
         for (const selector of selectors) {
             const listOptions: ListConfigurationSettingsOptions = {
@@ -240,7 +240,7 @@ export class AzureAppConfigurationImpl implements AzureAppConfiguration {
 
     async #loadFeatureFlags() {
         const featureFlags: FeatureFlagValue[] = [];
-        const featureFlagSelectors = getValidSelectors(this.#options?.featureFlagOptions?.selectors);
+        const featureFlagSelectors = getValidFeatureFlagSelectors(this.#options?.featureFlagOptions?.selectors);
         for (const selector of featureFlagSelectors) {
             const listOptions: ListConfigurationSettingsOptions = {
                 keyFilter: `${featureFlagPrefix}${selector.keyFilter}`,
@@ -465,12 +465,7 @@ export class AzureAppConfigurationImpl implements AzureAppConfiguration {
     }
 }
 
-function getValidSelectors(selectors?: SettingSelector[]) {
-    if (!selectors || selectors.length === 0) {
-        // Default selector: key: *, label: \0
-        return [{ keyFilter: KeyFilter.Any, labelFilter: LabelFilter.Null }];
-    }
-
+function validateSelectors(selectors: SettingSelector[]) {
     // below code deduplicates selectors by keyFilter and labelFilter, the latter selector wins
     const uniqueSelectors: SettingSelector[] = [];
     for (const selector of selectors) {
@@ -495,3 +490,20 @@ function getValidSelectors(selectors?: SettingSelector[]) {
         return selector;
     });
 }
+
+function getValidKeyValueSelectors(selectors?: SettingSelector[]) {
+    if (!selectors || selectors.length === 0) {
+        // Default selector: key: *, label: \0
+        return [{ keyFilter: KeyFilter.Any, labelFilter: LabelFilter.Null }];
+    }
+    return validateSelectors(selectors);
+}
+
+function getValidFeatureFlagSelectors(selectors?: SettingSelector[]) {
+    if (!selectors || selectors.length === 0) {
+        // selectors must be explicitly provided.
+        throw new Error("Feature flag selectors must be provided.");
+    } else {
+        return validateSelectors(selectors);
+    }
+}

test/featureFlag.test.ts

@@ -31,7 +31,10 @@ describe("feature flags", function () {
         const connectionString = createMockedConnectionString();
         const settings = await load(connectionString, {
             featureFlagOptions: {
-                enabled: true
+                enabled: true,
+                selectors: [{
+                    keyFilter: "*"
+                }]
             }
         });
         expect(settings).not.undefined;
@@ -50,13 +53,22 @@ describe("feature flags", function () {
         expect(settings.get("feature_management")).undefined;
     });
 
-    it("should not load feature flags if not specified", async () => {
+    it("should not load feature flags if featureFlagOptions not specified", async () => {
         const connectionString = createMockedConnectionString();
         const settings = await load(connectionString);
         expect(settings).not.undefined;
         expect(settings.get("feature_management")).undefined;
     });
 
+    it("should throw error if selectors not specified", async () => {
+        const connectionString = createMockedConnectionString();
+        return expect(load(connectionString, {
+            featureFlagOptions: {
+                enabled: true
+            }
+        })).eventually.rejectedWith("Feature flag selectors must be provided.");
+    });
+
     it("should load feature flags with custom selector", async () => {
         const connectionString = createMockedConnectionString();
         const settings = await load(connectionString, {