Desktop OIDC: full page nav to localhost, meta redirect back

SPA navigates to 127.0.0.1:18901/oidc/start, passing ret URL.
Go opens browser, waits for callback, saves token, returns HTML with
<meta refresh> back to Wails app with ?desktop=1&token=TOKEN.
main.ts extracts token from URL on reload.

web/src/lib/oidc.ts

@@ -103,7 +103,9 @@ export async function startLogin(): Promise<void> {
 
   if (isDesktop) {
     const apiUrl = getConfig().apiUrl || ''
-    throw new Error('DESKTOP_OIDC:' + apiUrl)
+    const ret = encodeURIComponent(location.origin + location.pathname.replace(/\/$/, '') + '?desktop=1')
+    location.href = `http://127.0.0.1:18901/oidc/start?apiUrl=${encodeURIComponent(apiUrl)}&ret=${ret}`
+    return
   }
 
   location.href = `${cfg.authorization_endpoint.replace(/\/$/, '')}/?${params}`

web/src/main.ts

@@ -1,10 +1,26 @@
 import { mount } from 'svelte'
 import App from './App.svelte'
 import './app.css'
-import { initConfig } from '$lib/config'
+import { initConfig, setConfig, getConfig } from '$lib/config'
+
+function handleDesktopToken() {
+  const params = new URLSearchParams(location.search)
+  const token = params.get('token')
+  if (token && new URLSearchParams(location.search).has('desktop')) {
+    const apiUrl = getConfig().apiUrl || ''
+    setConfig({ apiUrl, token, isDesktop: true })
+    initConfig({ apiUrl, token, isDesktop: true })
+    params.delete('token')
+    const q = params.toString()
+    history.replaceState(null, '', location.pathname + (q ? '?' + q : ''))
+    return true
+  }
+  return false
+}
 
 function start() {
   initConfig()
+  handleDesktopToken()
 
   requestAnimationFrame(() => import('./lib/renderers'))
 

web/src/pages/Config.svelte

@@ -72,43 +72,11 @@
     try {
       await startLogin()
     } catch (e: any) {
-      const msg = e?.message || e || ''
-      if (msg.startsWith('DESKTOP_OIDC:')) {
-        const url = msg.substring('DESKTOP_OIDC:'.length)
-        await desktopOIDC(url)
-        return
-      }
-      error = msg || 'OIDC login failed'
+      error = e.message || 'OIDC login failed'
       oidcLoggingIn = false
     }
   }
 
-  async function desktopOIDC(apiUrl: string) {
-    try {
-      const resp = await fetch(`http://127.0.0.1:18901/oidc/open?apiUrl=${encodeURIComponent(apiUrl)}`)
-      const { id } = await resp.json()
-      if (!id) throw new Error('No session ID')
-
-      for (let i = 0; i < 600; i++) {
-        await new Promise(r => setTimeout(r, 500))
-        const r = await fetch(`http://127.0.0.1:18901/oidc/result?id=${id}`)
-        const data = await r.json()
-        if (data.token) {
-          setConfig({ apiUrl, token: data.token, isDesktop: true })
-          initConfig({ apiUrl, token: data.token, isDesktop: true })
-          oidcLoggingIn = false
-          onConnected()
-          return
-        }
-        if (!data.pending || data.pending === 'false') break
-      }
-      error = 'Login timed out'
-    } catch (e: any) {
-      error = e?.message || 'Could not reach login service'
-    }
-    oidcLoggingIn = false
-  }
-
   function logoutOIDC() {
     oidcLogout()
     oidcUser = null