Add env var to use raw body and set max json size

This change adds the use of 2 environment variables allowing users to receive the
request body as a buffer (the 'raw' body) as well as the ability to set the maximum
JSON body size.
The raw body is required when processing Stripe webhooks
The max JSON body size is defaulted to a low limit from body-parser which has caused
issues with users in the past.

Signed-off-by: Burton Rheutan <[email protected]>

Author: burtonr

template/node12/index.js

@@ -8,10 +8,15 @@ const app = express()
 const handler = require('./function/handler');
 const bodyParser = require('body-parser')
 
-// app.use(bodyParser.urlencoded({ extended: false }));
-app.use(bodyParser.json());
-app.use(bodyParser.raw());
-app.use(bodyParser.text({ type : "text/*" }));
+if (process.env.RAW_BODY === 'true') {
+    app.use(bodyParser.raw({ type: '*/*' }))
+} else {
+    var jsonLimit = process.env.MAX_JSON_SIZE || '100kb' //body-parser default
+    app.use(bodyParser.json({ limit: jsonLimit}));
+    app.use(bodyParser.raw()); // "Content-Type: application/octet-stream"
+    app.use(bodyParser.text({ type : "text/*" }));
+}
+
 app.disable('x-powered-by');
 
 class FunctionEvent {