refresh option registerAll

Author: zhiyuanliang-ms

src/AzureAppConfigurationImpl.ts

@@ -75,6 +75,7 @@ export class AzureAppConfigurationImpl implements AzureAppConfiguration {
     #featureFlagRefreshTimer: RefreshTimer;
 
     // selectors
+    #keyValueSelectors: PagedSettingSelector[] = [];
     #featureFlagSelectors: PagedSettingSelector[] = [];
 
     constructor(
@@ -94,9 +95,10 @@ export class AzureAppConfigurationImpl implements AzureAppConfiguration {
         }
 
         if (options?.refreshOptions?.enabled) {
-            const { watchedSettings, refreshIntervalInMs } = options.refreshOptions;
-            // validate watched settings
-            if (watchedSettings === undefined || watchedSettings.length === 0) {
+            const { watchedSettings, refreshIntervalInMs, registerAll } = options.refreshOptions;
+            
+            // validate refresh options
+            if (registerAll !== true && (watchedSettings === undefined || watchedSettings.length === 0)) {
                 throw new Error("Refresh is enabled but no watched settings are specified.");
             }
 
@@ -110,19 +112,30 @@ export class AzureAppConfigurationImpl implements AzureAppConfiguration {
                 }
             }
 
-            for (const setting of watchedSettings) {
-                if (setting.key.includes("*") || setting.key.includes(",")) {
-                    throw new Error("The characters '*' and ',' are not supported in key of watched settings.");
+            if (registerAll !== true) {
+                if (watchedSettings === undefined || watchedSettings.length === 0) {
+                    throw new Error("Refresh is enabled but no watched settings are specified.");
                 }
-                if (setting.label?.includes("*") || setting.label?.includes(",")) {
-                    throw new Error("The characters '*' and ',' are not supported in label of watched settings.");
+                else {
+                    for (const setting of watchedSettings) {
+                        if (setting.key.includes("*") || setting.key.includes(",")) {
+                            throw new Error("The characters '*' and ',' are not supported in key of watched settings.");
+                        }
+                        if (setting.label?.includes("*") || setting.label?.includes(",")) {
+                            throw new Error("The characters '*' and ',' are not supported in label of watched settings.");
+                        }
+                        this.#sentinels.push(setting);
+                    }
                 }
-                this.#sentinels.push(setting);
+            } else if (watchedSettings && watchedSettings.length > 0) {
+                throw new Error("Watched settings should not be specified when registerAll is enabled.");
             }
 
             this.#refreshTimer = new RefreshTimer(this.#refreshInterval);
         }
 
+        this.#keyValueSelectors = getValidKeyValueSelectors(options?.selectors);
+
         // feature flag options
         if (options?.featureFlagOptions?.enabled) {
             // validate feature flag selectors
@@ -185,6 +198,10 @@ export class AzureAppConfigurationImpl implements AzureAppConfiguration {
         return !!this.#options?.refreshOptions?.enabled;
     }
 
+    get #registerAll(): boolean {
+        return !!this.#options?.refreshOptions?.registerAll;
+    }
+
     get #featureFlagEnabled(): boolean {
         return !!this.#options?.featureFlagOptions?.enabled;
     }
@@ -204,26 +221,27 @@ export class AzureAppConfigurationImpl implements AzureAppConfiguration {
     async #loadSelectedKeyValues(): Promise<ConfigurationSetting[]> {
         const loadedSettings: ConfigurationSetting[] = [];
 
-        // validate selectors
-        const selectors = getValidKeyValueSelectors(this.#options?.selectors);
-
-        for (const selector of selectors) {
+        for (const selector of this.#keyValueSelectors) {
             const listOptions: ListConfigurationSettingsOptions = {
                 keyFilter: selector.keyFilter,
                 labelFilter: selector.labelFilter
             };
 
-            const settings = listConfigurationSettingsWithTrace(
+            const pageEtags: string[] = [];
+            const pageIterator = listConfigurationSettingsWithTrace(
                 this.#requestTraceOptions,
                 this.#client,
                 listOptions
-            );
-
-            for await (const setting of settings) {
-                if (!isFeatureFlag(setting)) { // exclude feature flags
-                    loadedSettings.push(setting);
+            ).byPage();
+            for await (const page of pageIterator) {
+                pageEtags.push(page.etag ?? "");
+                for (const setting of page.items) {
+                    if (!isFeatureFlag(setting)) { // exclude feature flags
+                        loadedSettings.push(setting);
+                    }
                 }
             }
+            selector.pageEtags = pageEtags;
         }
         return loadedSettings;
     }
@@ -232,10 +250,6 @@ export class AzureAppConfigurationImpl implements AzureAppConfiguration {
      * Update etag of watched settings from loaded data. If a watched setting is not covered by any selector, a request will be sent to retrieve it.
      */
     async #updateWatchedKeyValuesEtag(existingSettings: ConfigurationSetting[]): Promise<void> {
-        if (!this.#refreshEnabled) {
-            return;
-        }
-
         for (const sentinel of this.#sentinels) {
             const matchedSetting = existingSettings.find(s => s.key === sentinel.key && s.label === sentinel.label);
             if (matchedSetting) {
@@ -256,7 +270,9 @@ export class AzureAppConfigurationImpl implements AzureAppConfiguration {
     async #loadSelectedAndWatchedKeyValues() {
         const keyValues: [key: string, value: unknown][] = [];
         const loadedSettings = await this.#loadSelectedKeyValues();
-        await this.#updateWatchedKeyValuesEtag(loadedSettings);
+        if (!this.#registerAll) {
+            await this.#updateWatchedKeyValuesEtag(loadedSettings);
+        }
 
         // process key-values, watched settings have higher priority
         for (const setting of loadedSettings) {
@@ -413,19 +429,46 @@ export class AzureAppConfigurationImpl implements AzureAppConfiguration {
             return Promise.resolve(false);
         }
 
-        // try refresh if any of watched settings is changed.
         let needRefresh = false;
-        for (const sentinel of this.#sentinels.values()) {
-            const response = await this.#getConfigurationSetting(sentinel, {
-                onlyIfChanged: true
-            });
-
-            if (response?.statusCode === 200 // created or changed
-                || (response === undefined && sentinel.etag !== undefined) // deleted
-            ) {
-                sentinel.etag = response?.etag;// update etag of the sentinel
-                needRefresh = true;
-                break;
+        if (this.#registerAll) {
+            // check whether there is any change based on page etags
+            for (const selector of this.#featureFlagSelectors) {
+                const listOptions: ListConfigurationSettingsOptions = {
+                    keyFilter: selector.keyFilter,
+                    labelFilter: selector.labelFilter,
+                    pageEtags: selector.pageEtags // when etags are provided, sdk will send conditional request
+                };
+                const pageIterator = listConfigurationSettingsWithTrace(
+                    this.#requestTraceOptions,
+                    this.#client,
+                    listOptions
+                ).byPage();
+    
+                for await (const page of pageIterator) {
+                    if (page._response.status === 200) { // created or changed
+                        needRefresh = true;
+                        break;
+                    }
+                }
+    
+                if (needRefresh) {
+                    break; // short-circuit if result from any of the selectors is changed
+                }
+            }
+        } else {
+            // check whether there is any change based on watched settings etags
+            for (const sentinel of this.#sentinels.values()) {
+                const response = await this.#getConfigurationSetting(sentinel, {
+                    onlyIfChanged: true
+                });
+
+                if (response?.statusCode === 200 // created or changed
+                    || (response === undefined && sentinel.etag !== undefined) // deleted (404 exception is caught in #getConfigurationSetting)
+                ) {
+                    sentinel.etag = response?.etag;// update etag of the sentinel
+                    needRefresh = true;
+                    break;
+                }
             }
         }
 
@@ -779,15 +822,15 @@ function getValidSelectors(selectors: SettingSelector[]): SettingSelector[] {
 }
 
 function getValidKeyValueSelectors(selectors?: SettingSelector[]): SettingSelector[] {
-    if (!selectors || selectors.length === 0) {
+    if (selectors === undefined || selectors.length === 0) {
         // Default selector: key: *, label: \0
         return [{ keyFilter: KeyFilter.Any, labelFilter: LabelFilter.Null }];
     }
     return getValidSelectors(selectors);
 }
 
 function getValidFeatureFlagSelectors(selectors?: SettingSelector[]): SettingSelector[] {
-    if (!selectors || selectors.length === 0) {
+    if (selectors === undefined || selectors.length === 0) {
         // selectors must be explicitly provided.
         throw new Error("Feature flag selectors must be provided.");
     } else {

src/RefreshOptions.ts

@@ -24,6 +24,11 @@ export interface RefreshOptions {
      * Any modifications to watched settings will refresh all settings loaded by the configuration provider when refresh() is called.
      */
     watchedSettings?: WatchedSetting[];
+
+    /**
+     * Specifies whether all configuration settings will be watched for changes on the server.
+     */
+    registerAll?: boolean;
 }
 
 export interface FeatureFlagRefreshOptions {