test: cover initial api url resolution

Author: ammarlakis

frontend/src/helpers/apiUrl.test.ts

@@ -0,0 +1,29 @@
+import {describe, expect, it} from 'vitest'
+
+import {resolveInitialApiUrl} from './apiUrl'
+
+describe('resolveInitialApiUrl', () => {
+	it('keeps the injected api url when a stale stored url exists', () => {
+		const apiUrl = resolveInitialApiUrl('/api/v1', 'https://tasks.example.com/api/v1')
+
+		expect(apiUrl).toBe('/api/v1')
+	})
+
+	it('uses the stored api url when no api url was injected', () => {
+		const apiUrl = resolveInitialApiUrl('', 'https://tasks.example.com/api/v1')
+
+		expect(apiUrl).toBe('https://tasks.example.com/api/v1')
+	})
+
+	it('removes a trailing slash from the selected api url', () => {
+		const apiUrl = resolveInitialApiUrl('/api/v1/', 'https://tasks.example.com/api/v1/')
+
+		expect(apiUrl).toBe('/api/v1')
+	})
+
+	it('keeps an empty api url when neither source provides one', () => {
+		const apiUrl = resolveInitialApiUrl('', null)
+
+		expect(apiUrl).toBe('')
+	})
+})

frontend/src/helpers/apiUrl.ts

@@ -0,0 +1,13 @@
+export function resolveInitialApiUrl(injectedApiUrl: string, storedApiUrl: string | null): string {
+	let apiUrl = injectedApiUrl
+
+	if (storedApiUrl !== null && apiUrl === '') {
+		apiUrl = storedApiUrl
+	}
+
+	if (apiUrl.endsWith('/')) {
+		apiUrl = apiUrl.slice(0, -1)
+	}
+
+	return apiUrl
+}

frontend/src/main.ts

@@ -4,6 +4,7 @@ import pinia from './pinia'
 import router from './router'
 import App from './App.vue'
 import {error, success} from './message'
+import {resolveInitialApiUrl} from '@/helpers/apiUrl'
 
 // Notifications
 import Notifications from '@kyvg/vue3-notification'
@@ -24,18 +25,7 @@ declare global {
 	}
 }
 
-// Check if we have an api url in local storage and use it if the bundled
-// frontend did not provide one. This prevents stale values from another host
-// from overriding the same-origin default and causing CORS failures.
-const apiUrlFromStorage = localStorage.getItem('API_URL')
-if (apiUrlFromStorage !== null && window.API_URL === '') {
-	window.API_URL = apiUrlFromStorage
-}
-
-// Make sure the api url does not contain a / at the end
-if (window.API_URL.endsWith('/')) {
-	window.API_URL = window.API_URL.slice(0, -1)
-}
+window.API_URL = resolveInitialApiUrl(window.API_URL, localStorage.getItem('API_URL'))
 
 // directives
 import focus from '@/directives/focus'