Chris/schy 49 add timeouts to node sdk (#78)

* allow configuring of request timeout

* add defaultvalue argument to flagcheck

* refactor checkFlag signature to accept and options object and implement per flag check timeout

* use milliseconds for timeouts

Author: cbrady

src/wrapper.ts

@@ -31,6 +31,15 @@ export interface SchematicOptions {
     logger?: Logger;
     /** Enable offline mode to prevent network activity */
     offline?: boolean;
+    /** The default maximum time to wait for a response in milliseconds */
+    timeoutMs?: number;
+}
+
+export interface CheckFlagOptions {
+    /** Default value to return on error. Can be a boolean or a function returning a boolean. If not provided, uses configured flag defaults */
+    defaultValue?: boolean | (() => boolean);
+    /** The maximum time to wait for a response in milliseconds */
+    timeoutMs?: number;
 }
 
 export class SchematicClient extends BaseClient {
@@ -51,6 +60,7 @@ export class SchematicClient extends BaseClient {
             eventBufferInterval,
             flagDefaults = {},
             logger = new ConsoleLogger(),
+            timeoutMs,
         } = opts ?? {};
         let { offline = false } = opts ?? {};
 
@@ -78,6 +88,7 @@ export class SchematicClient extends BaseClient {
             apiKey,
             environment: basePath,
             fetcher: offline ? offlineFetcher : provideFetcher(headers),
+            timeoutInSeconds: timeoutMs !== undefined ? timeoutMs / 1000 : undefined,
         });
 
         this.logger = logger;
@@ -95,13 +106,21 @@ export class SchematicClient extends BaseClient {
      * Checks the value of a feature flag for the given evaluation context
      * @param evalCtx - The context (company and/or user) for evaluating the feature flag
      * @param key - The unique identifier of the feature flag
+     * @param options - Optional configuration for the flag check
      * @returns Promise resolving to the flag's boolean value, falling back to default if unavailable
      * @throws Will log error and return flag default if check fails
      */
-    async checkFlag(evalCtx: api.CheckFlagRequestBody, key: string): Promise<boolean> {
+    async checkFlag(evalCtx: api.CheckFlagRequestBody, key: string, options?: CheckFlagOptions): Promise<boolean> {
+        const getDefault = (): boolean => {
+            if (options?.defaultValue === undefined) {
+                return this.getFlagDefault(key);
+            }
+            return typeof options.defaultValue === "function" ? options.defaultValue() : options.defaultValue;
+        };
+
         if (this.offline) {
             this.logger.debug(`Offline mode enabled, returning default flag value for flag ${key}`);
-            return this.getFlagDefault(key);
+            return getDefault();
         }
 
         try {
@@ -114,10 +133,12 @@ export class SchematicClient extends BaseClient {
                 }
             }
 
-            const response = await this.features.checkFlag(key, evalCtx);
+            const response = await this.features.checkFlag(key, evalCtx, {
+                timeoutInSeconds: options?.timeoutMs !== undefined ? options.timeoutMs / 1000 : undefined,
+            });
             if (response.data.value === undefined) {
                 this.logger.debug(`No value returned from feature flag API for flag ${key}, falling back to default`);
-                return this.getFlagDefault(key);
+                return getDefault();
             }
 
             for (const provider of this.flagCheckCacheProviders) {
@@ -129,7 +150,7 @@ export class SchematicClient extends BaseClient {
             return response.data.value;
         } catch (err) {
             this.logger.error(`Error checking flag ${key}: ${err}`);
-            return this.getFlagDefault(key);
+            return getDefault();
         }
     }