From 50dbd4ee5257dae16a80c6fe52aefbcf54698d7e Mon Sep 17 00:00:00 2001
From: Pig Fang <g-plane@hotmail.com>
Date: Wed, 22 May 2019 23:55:37 +0800
Subject: [PATCH] Better UX for backend errors (fix #64)

---
 resources/assets/src/scripts/net.ts        | 19 +++++-----
 resources/assets/tests/scripts/net.test.ts | 44 +++++++++++++++++-----
 2 files changed, 44 insertions(+), 19 deletions(-)

diff --git a/resources/assets/src/scripts/net.ts b/resources/assets/src/scripts/net.ts
index d81e4d33..57ad8643 100644
--- a/resources/assets/src/scripts/net.ts
+++ b/resources/assets/src/scripts/net.ts
@@ -1,7 +1,7 @@
 import Vue from 'vue'
 import { emit } from './event'
 import { queryStringify } from './utils'
-import { showAjaxError } from './notify'
+import { showAjaxError, showModal } from './notify'
 
 class HTTPError extends Error {
   response: Response
@@ -30,26 +30,27 @@ export async function walkFetch(request: Request): Promise<any> {
 
   try {
     const response = await fetch(request)
+    const body = response.headers.get('Content-Type') === 'application/json'
+      ? await response.json()
+      : await response.text()
     if (response.ok) {
-      return response.headers.get('Content-Type') === 'application/json'
-        ? response.json()
-        : response.text()
+      return body
     }
 
     // Process validation errors from Laravel.
     if (response.status === 422) {
-      const { errors }: {
-        message: string,
-        errors: { [field: string]: string[] }
-      } = await response.json()
+      const { errors }: { message: string, errors: { [field: string]: string[] } } = body
       return {
         code: 1,
         message: Object.keys(errors).map(field => errors[field][0])[0],
       }
+    } else if (response.status === 403) {
+      showModal(body.message, undefined, 'warning')
+      return
     }
 
     const res = response.clone()
-    throw new HTTPError(await response.text(), res)
+    throw new HTTPError(body.message || body, res)
   } catch (error) {
     emit('fetchError', error)
     showAjaxError(error)
diff --git a/resources/assets/tests/scripts/net.test.ts b/resources/assets/tests/scripts/net.test.ts
index 6e7c51c4..68064ab5 100644
--- a/resources/assets/tests/scripts/net.test.ts
+++ b/resources/assets/tests/scripts/net.test.ts
@@ -1,7 +1,7 @@
 import Vue from 'vue'
 import * as net from '@/scripts/net'
 import { on } from '@/scripts/event'
-import { showAjaxError } from '@/scripts/notify'
+import { showAjaxError, showModal } from '@/scripts/notify'
 
 jest.mock('@/scripts/notify')
 
@@ -77,9 +77,16 @@ test('low level fetch', async () => {
     .mockRejectedValueOnce(new Error('network'))
     .mockResolvedValueOnce({
       ok: false,
+      headers: new Map(),
       text: () => Promise.resolve('404'),
       clone: () => ({}),
     })
+    .mockResolvedValueOnce({
+      ok: false,
+      json: () => Promise.resolve({ message: 'error' }),
+      headers: new Map([['Content-Type', 'application/json']]),
+      clone: () => ({}),
+    })
     .mockResolvedValueOnce({
       ok: true,
       json,
@@ -106,21 +113,35 @@ test('low level fetch', async () => {
   expect(stub.mock.calls[1][0]).toHaveProperty('message', '404')
   expect(stub.mock.calls[1][0]).toHaveProperty('response')
 
+  await net.walkFetch(request as Request)
+  expect(showAjaxError.mock.calls[2][0]).toBeInstanceOf(Error)
+  expect(stub.mock.calls[2][0]).toHaveProperty('message', 'error')
+  expect(stub.mock.calls[2][0]).toHaveProperty('response')
+
   await net.walkFetch(request as Request)
   expect(json).toBeCalled()
 
   expect(await net.walkFetch(request as Request)).toBe('text')
 })
 
-test('process Laravel validation errors', async () => {
-  window.fetch = jest.fn().mockResolvedValue({
-    status: 422,
-    json() {
-      return Promise.resolve({
-        errors: { name: ['required'] },
-      })
-    },
-  })
+test('process backend errors', async () => {
+  window.fetch = jest.fn()
+    .mockResolvedValueOnce({
+      status: 422,
+      headers: new Map([['Content-Type', 'application/json']]),
+      json() {
+        return Promise.resolve({
+          errors: { name: ['required'] },
+        })
+      },
+    })
+    .mockResolvedValueOnce({
+      status: 403,
+      headers: new Map([['Content-Type', 'application/json']]),
+      json() {
+        return Promise.resolve({ message: 'forbidden' })
+      },
+    })
 
   const result: {
     code: number,
@@ -128,6 +149,9 @@ test('process Laravel validation errors', async () => {
   } = await net.walkFetch({ headers: new Headers() } as Request)
   expect(result.code).toBe(1)
   expect(result.message).toBe('required')
+
+  await net.walkFetch({ headers: new Headers() } as Request)
+  expect(showModal).toBeCalledWith('forbidden', undefined, 'warning')
 })
 
 test('inject to Vue instance', () => {