json-syntax-error

This is a small middleware to resolve syntax errors in your express app

Usage no npm install needed!

<script type="module">
  import jsonSyntaxError from 'https://cdn.skypack.dev/json-syntax-error';
</script>

README

json-syntax-error

David npm bundle size NPM

Middleware to help you to catch syntax errors in JSON sent to your express server and give you a much cleaner error

Ever tried sending an invalid JSON syntax to your express server when you use it with body-parser or express.json() and you get an ugly error at your client side?

Tired of seeing your server throwing Syntax error when an invalid JSON data is forced down it's throat?


<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="utf-8">
<title>Error</title>
</head>
<body>
<pre>SyntaxError: Unexpected string in JSON at position 53<br> at JSON.parse (&lt;anonymous&gt;)<br>
   at parse (/home/pc/Desktop/TC/tc-sample/node_modules/body-parser/lib/types/json.js:89:19)<br>
   at /home/pc/Desktop/TC/tc-sample/node_modules/body-parser/lib/read.js:121:18<br>
   at invokeCallback (/home/pc/Desktop/TC/tc-sample/node_modules/raw-body/index.js:224:16)<br>
   at done (/home/pc/Desktop/TC/tc-sample/node_modules/raw-body/index.js:213:7)<br>
   at IncomingMessage.onEnd (/home/pc/Desktop/TC/tc-sample/node_modules/raw-body/index.js:273:7)<br>
   at IncomingMessage.emit (events.js:327:22)<br>
   at endReadableNT (_stream_readable.js:1220:12)<br> 
   at processTicksAndRejections (internal/process/task_queues.js:84:21)</pre>
</body>
</html>

This small middleware will help you to resolve syntax errors in your express server by allowing you to catch the error early and returning a cleaner error

{
   "status": "fail",
   "message": "Invalid JSON: The server is unable to process your request as it is badly malformed!
}

Installing / Getting started

Install via npm

npm install json-syntax-error --save

Configuration is easy, as a, b, c. Just require('json-syntax-error') anywhere below your json parser (express.json() or bodyParser.json())


const JSONSyntaxErr =  require('json-syntax-error')
...
const app = express();
...
app.use(express.json());
app.use(JSONSyntaxErr()); // That's all, really!

...

You can also pass in your custom response. It can be JSON, HTML, text or any format allowed by express .send()

app.use(JSONSyntaxErr({ error: 'Why are you sending a bad json?' })); // Torture their conscience!

or

app.use(JSONSyntaxErr('<p>Really? A bad JSON? Really?</p>')); // Wasn't hard, was it?!

Tests

npm test