Incorrect Data (empty body) returned through req: lambda + API gateway

### app.post("/path/path", (req, res) => { }

I am not sure what exactly is the issue is, but it seems that my **req** variable contains weird data from aws- api gateway. When I try log the contents I get a circular error. The data exists in the event variable with the following code in my index .js:

```
const awsServerlessExpress = require('aws-serverless-express');
const app = require('./app');

const server = awsServerlessExpress.createServer(app);

exports.handler = (event, context) => {
console.log(`EVENT: ${JSON.stringify(event)}`);
return awsServerlessExpress.proxy(server, event, context, 'PROMISE').promise;
};

```

Then in my app.js i have the following code:

``` // app modules
var express = require("express");
var bodyParser = require("body-parser");
var awsServerlessExpressMiddleware = require("aws-serverless-express/middleware");

// declare a new express app
var app = express();
app.use(bodyParser.json());
app.use(awsServerlessExpressMiddleware.eventContext());

// Enable CORS for all methods
app.use(function (req, res, next) {
res.header("Access-Control-Allow-Origin", "*");
res.header("Access-Control-Allow-Headers", "*");
next();
});

app.post("/NotifyUrl-crprod/payfast", (req, res) => {

console.log("body" + Object.keys(req), Object.values(req));
console.log("body1" + req);
})
```
The req parameter contains stuff except the data that was actually sent through from api gateway, i.e. the data (body) doesn't exist in the **req**, even though it exists in **event** . The screenshots below are printouts of the keys and values that are printed out and the event variable data . These keys are not the issue, the issue is that the desired data doesn't appear at all **req.body** is empty. logging out the **req** will through a circular reference error which is okay, but the desired data is not present.

These are the different dependency version being used:
```
"aws-serverless-express": "^3.4.0",
"body-parser": "^1.17.1",
"express": "^4.15.2",
```

The below event printout screenshot is only a fraction of the full data that is contained in req.


Start with index.js and app.js, then compare the logged API Gateway event with the data exposed to the Express handler at /NotifyUrl-crprod/payfast. Reproduce the POST request and verify whether req.body contains the submitted payload; done means the request body is available in the handler or the integration boundary causing it to be absent is identified.

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