fix: new client mode vs singleton client mode (#139)

Author: kwasniew

src/app.ts

@@ -7,7 +7,7 @@ import { createProxyConfig, IProxyOption } from './config';
 import UnleashProxy from './unleash-proxy';
 import { OpenApiService } from './openapi/openapi-service';
 import requireContentType from './content-type-checker';
-import { createClient } from './create-client';
+import { createSingletonClient, createNewClient } from './create-client';
 
 export function createApp(
     options: IProxyOption,
@@ -17,7 +17,11 @@ export function createApp(
     const config = createProxyConfig(options);
     const { logger } = config;
     logger.debug('Configuration:', config);
-    const client = unleashClient || createClient(config);
+    const client =
+        unleashClient ||
+        (options.clientMode === 'new'
+            ? createNewClient(config)
+            : createSingletonClient(config));
 
     const openApiService = new OpenApiService(config);
 

src/config.ts

@@ -42,6 +42,7 @@ export interface IProxyOption {
     expServerSideSdkConfig?: ServerSideSdkConfig;
     httpOptions?: HttpOptions;
     expCustomEnrichers?: ContextEnricher[];
+    clientMode?: 'singleton' | 'new';
 }
 
 export interface IProxyConfig {

src/create-client.ts

@@ -1,10 +1,10 @@
 import { IProxyConfig } from './config';
 import Client from './client';
-import { initialize } from 'unleash-client';
+import { initialize, Unleash } from 'unleash-client';
 import Metrics from 'unleash-client/lib/metrics';
 import { defaultStrategies } from 'unleash-client/lib/strategy';
 
-export const createClient = (config: IProxyConfig): Client => {
+export const createSingletonClient = (config: IProxyConfig): Client => {
     const customHeadersFunction = async () => ({
         Authorization: config.unleashApiToken,
     });
@@ -40,3 +40,40 @@ export const createClient = (config: IProxyConfig): Client => {
 
     return new Client(config, unleash, metrics);
 };
+
+export const createNewClient = (config: IProxyConfig): Client => {
+    const customHeadersFunction = async () => ({
+        Authorization: config.unleashApiToken,
+    });
+
+    const unleash = new Unleash({
+        url: config.unleashUrl,
+        appName: config.unleashAppName,
+        instanceId: config.unleashInstanceId,
+        environment: config.environment,
+        refreshInterval: config.refreshInterval,
+        projectName: config.projectName,
+        strategies: config.customStrategies,
+        disableMetrics: true,
+        namePrefix: config.namePrefix,
+        tags: config.tags,
+        customHeadersFunction,
+        bootstrap: config.bootstrap,
+        storageProvider: config.storageProvider,
+        ...(!!config.httpOptions ? { httpOptions: config.httpOptions } : {}),
+    });
+
+    const metrics = new Metrics({
+        disableMetrics: config.disableMetrics,
+        appName: config.unleashAppName,
+        instanceId: config.unleashInstanceId,
+        strategies: defaultStrategies.map((s) => s.name),
+        metricsInterval: config.metricsInterval,
+        metricsJitter: config.metricsJitter,
+        url: config.unleashUrl,
+        customHeadersFunction,
+        ...(!!config.httpOptions ? { httpOptions: config.httpOptions } : {}),
+    });
+
+    return new Client(config, unleash, metrics);
+};