From 362d4680de9164aac8c4b4c3f6c5a0d6ffcaf8fc Mon Sep 17 00:00:00 2001
From: Ben White <ben@posthog.com>
Date: Tue, 5 Dec 2023 09:06:53 +0100
Subject: [PATCH] fix: Sanitize given api_host urls to not have a trailing
 slash

---
 src/__tests__/posthog-core.js | 9 +++++++++
 src/posthog-core.ts           | 2 ++
 2 files changed, 11 insertions(+)

diff --git a/src/__tests__/posthog-core.js b/src/__tests__/posthog-core.js
index f9262e0ab..7db3a4f6c 100644
--- a/src/__tests__/posthog-core.js
+++ b/src/__tests__/posthog-core.js
@@ -702,6 +702,15 @@ describe('posthog core', () => {
             expect(given.overrides._send_request.mock.calls.length).toBe(0) // No outgoing requests
         })
 
+        it('sanitizes api_host urls', () => {
+            given('config', () => ({
+                api_host: 'https://example.com/custom/',
+            }))
+            given.subject()
+
+            expect(given.lib.config.api_host).toBe('https://example.com/custom')
+        })
+
         it('does not set __loaded_recorder_version flag if recording script has not been included', () => {
             given('overrides', () => ({
                 __loaded_recorder_version: undefined,
diff --git a/src/posthog-core.ts b/src/posthog-core.ts
index 0de7d319a..4deecff6f 100644
--- a/src/posthog-core.ts
+++ b/src/posthog-core.ts
@@ -1712,6 +1712,8 @@ export class PostHog {
                 this.config.disable_persistence = this.config.disable_cookie
             }
 
+            // We assume the api_host is without a trailing slash in most places throughout the codebase
+            this.config.api_host = this.config.api_host.replace(/\/$/, '')
             this.persistence?.update_config(this.config)
             this.sessionPersistence?.update_config(this.config)