格子链接与 Back4App 的集成答案

【问题标题】：Plaid Link integration with Back4App格子链接与 Back4App 的集成
【发布时间】：2020-12-18 13:21:47
【问题描述】：

开发新手，实际上只是将格子链接集成 (https://plaid.com/docs/#integrating-with-link) 复制并粘贴到客户端代码的基本 HTML 页面中，并直接粘贴到服务器端代码的 back4app 的云代码 (Node JS) 中，然后调用从云端运行，但没有任何反应，我收到以下错误：

Fetch API 无法加载 file:///create_link_token。对于 CORS 请求，URL 方案必须是“http”或“https”。

index2.html:42 Uncaught (in promise) TypeError: 无法获取在 fetchLinkToken (index2.html:42)

parse.min.js:13 POST https://parseapi.back4app.com/functions/plaidAPI400

parse.min.js:13 Uncaught (in promise) 错误：无效函数：“plaidAPI” 在句柄错误

我的 Html 代码如下：

<html>
<head>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width">
  <script type="text/javascript"  src="https://cdnjs.cloudflare.com/ajax/libs/parse/2.1.0/parse.js"></script>
  <script type="text/javascript" src="https://npmcdn.com/parse/dist/parse.min.js"></script>
  <title>JS Bin</title>
  <style>
    .inputs{
      margin: 30px 0px;
    }
    .inputs input{
      margin: 5px 0px;
      height: 20px;
    }
  </style>
</head>
<body>
<div align="center">
   <div class="title">
     <h1>Test</h1>
   </div>
</div>
<button id="link-button">Link Account</button>
<script src="js/credentials.js"></script>
<script src="https://cdn.plaid.com/link/v2/stable/link-initialize.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/2.2.3/jquery.min.js"></script>
<script src="js/server.js"></script>
<script type="text/javascript">
(async function($) {
  const fetchLinkToken = async () => {
    const response = await fetch('/create_link_token', { method: 'POST' });
    const responseJSON = await response.json();
    return responseJSON.link_token;
  };

  const configs = {
 
    token: await fetchLinkToken(),
    onLoad: function() {
      // Optional, called when Link loads
    },
    onSuccess: async function(public_token, metadata) {
      
      await fetch('/get_access_token', {
        method: 'POST',
        body: JSON.stringify({ public_token: public_token }),
      });
    },
    onExit: async function(err, metadata) {
      // The user exited the Link flow.
      if (err != null) {
        // The user encountered a Plaid API error prior to exiting.
        if (err.error_code === 'INVALID_LINK_TOKEN') {
          
          handler.destroy();
          handler = Plaid.create({
            ...configs,
            token: await fetchLinkToken(),
          });
        }
      }
      
    },
    onEvent: function(eventName, metadata) {
      }
    }
  };

  let handler = Plaid.create(configs);


  $('#link-button').on('click', function(e) {
    handler.open();
  });
})(jQuery);
</script>
<script id="plaid">
  Parse.Cloud.run("plaidAPI")
  </script>



</body>



</body>
</html>

这是我的云代码：


var bodyParser = require('body-parser');
var express = require('express');
var plaid = require('plaid');

// We store the access_token in memory - in production, store it in
// a secure persistent data store.
let ACCESS_TOKEN = null;
let ITEM_ID = null;

const client = new plaid.Client({
  clientID: 'Hidden-For-Obvious-Reasons',
  secret: 'Hidden-For-Obvious-Reasons',
  env: plaid.environments.sandbox
});

const app = express();

// Create a link_token to initialize Link
app.post('/create_link_token', async function(request, response, next) {
  // Grab the client_user_id by searching for the current user in your database
  const user = await User.find(...);
  const clientUserId = user.id;

  // Create the link_token with all of your configurations
  client.createLinkToken({
    user: {
      client_user_id: clientUserId,
    },
    client_name: 'My App',
    products: ['transactions'],
    country_codes: ['US'],
    language: 'en',
    webhook: 'https://sample.webhook.com',
  }, function(error, linkTokenResponse) {
    // Pass the result to your client-side app to initialize Link
    response.json({ link_token: linkTokenResponse.link_token });
  });
});

// Accept the public_token sent from Link
app.post('/get_access_token', function(request, response, next) {
  const public_token = request.body.public_token;
  client.exchangePublicToken(public_token, function(error, response) {
    if (error != null) {
      console.log('Could not exchange public_token!' + '\n' + error);
      return response.json({error: msg});
    }

    // Store the access_token and item_id in your database
    ACCESS_TOKEN = response.access_token;
    ITEM_ID = response.item_id;

    console.log('Access Token: ' + ACCESS_TOKEN);
    console.log('Item ID: ' + ITEM_ID);
    response.json({'error': false});
  });
});
app.listen(8000);
}

【问题讨论】：

您首先需要决定是要创建cloud code function 还是custom express route。您当前正在创建自定义快速路由并像调用云代码函数一样调用它。

标签： javascript html node.js parse-platform plaid

【解决方案1】：

需要通过快速路由启动节点，而不是调用云代码。

【讨论】：