From 6b90edef649e6560a2d4a53f5da387cbdb6344ed Mon Sep 17 00:00:00 2001
From: Nicky Bondarenko <nickyb@spotify.com>
Date: Tue, 10 Sep 2024 15:49:35 +0200
Subject: [PATCH] feat: add a custom baseURL for sidecar resolves

---
 packages/sdk/src/Confidence.ts         |  5 +++++
 packages/sdk/src/FlagResolverClient.ts | 13 +++++++++++--
 2 files changed, 16 insertions(+), 2 deletions(-)

diff --git a/packages/sdk/src/Confidence.ts b/packages/sdk/src/Confidence.ts
index c27fd8dd..5ddd9437 100644
--- a/packages/sdk/src/Confidence.ts
+++ b/packages/sdk/src/Confidence.ts
@@ -38,6 +38,8 @@ export interface ConfidenceOptions {
   timeout: number;
   /** Debug logger */
   logger?: Logger;
+  /** Backend only option. Sets an alternative resolve url */
+  APIResolveBaseUrl?: string;
 }
 
 /**
@@ -323,6 +325,7 @@ export class Confidence implements EventSender, Trackable, FlagResolver {
    * @param environment - can be either "client" or "backend"
    * @param fetchImplementation - fetch implementation
    * @param logger - debug logger
+   * @param APIResolveBaseUrl - custom backend resolve URL
    * @returns
    */
   static create({
@@ -332,6 +335,7 @@ export class Confidence implements EventSender, Trackable, FlagResolver {
     environment,
     fetchImplementation = defaultFetchImplementation(),
     logger = defaultLogger(),
+    APIResolveBaseUrl,
   }: ConfidenceOptions): Confidence {
     const sdk = {
       id: SdkId.SDK_ID_JS_CONFIDENCE,
@@ -344,6 +348,7 @@ export class Confidence implements EventSender, Trackable, FlagResolver {
       environment,
       resolveTimeout: timeout,
       region,
+      APIResolveBaseUrl,
     });
     if (environment === 'client') {
       flagResolverClient = new CachingFlagResolverClient(flagResolverClient, Number.POSITIVE_INFINITY);
diff --git a/packages/sdk/src/FlagResolverClient.ts b/packages/sdk/src/FlagResolverClient.ts
index 94dc8ef3..4adb35a6 100644
--- a/packages/sdk/src/FlagResolverClient.ts
+++ b/packages/sdk/src/FlagResolverClient.ts
@@ -16,7 +16,10 @@ import { SimpleFetch } from './types';
 const FLAG_PREFIX = 'flags/';
 
 export class ResolveError extends Error {
-  constructor(public readonly code: FlagEvaluation.ErrorCode, message: string) {
+  constructor(
+    public readonly code: FlagEvaluation.ErrorCode,
+    message: string,
+  ) {
     super(message);
   }
 }
@@ -84,6 +87,7 @@ export type FlagResolverClientOptions = {
   resolveTimeout: number;
   environment: 'client' | 'backend';
   region?: 'eu' | 'us';
+  APIResolveBaseUrl?: string;
 };
 
 export class FetchingFlagResolverClient implements FlagResolverClient {
@@ -103,13 +107,18 @@ export class FetchingFlagResolverClient implements FlagResolverClient {
     // todo refactor to move out environment
     environment,
     region,
+    APIResolveBaseUrl,
   }: FlagResolverClientOptions) {
     // TODO think about both resolve and apply request logic for backends
     this.fetchImplementation = environment === 'backend' ? fetchImplementation : withRequestLogic(fetchImplementation);
     this.clientSecret = clientSecret;
     this.sdk = sdk;
     this.applyTimeout = applyTimeout;
-    this.baseUrl = region ? `https://resolver.${region}.confidence.dev/v1` : 'https://resolver.confidence.dev/v1';
+    if (environment === 'backend' && APIResolveBaseUrl) {
+      this.baseUrl = APIResolveBaseUrl;
+    } else {
+      this.baseUrl = region ? `https://resolver.${region}.confidence.dev/v1` : 'https://resolver.confidence.dev/v1';
+    }
     this.resolveTimeout = resolveTimeout;
   }