fix: cloudevents from 3.2.0 to 4.0.0 (#376)

* fix: examples/express-ex/package.json to reduce vulnerabilities

The following vulnerabilities are fixed with an upgrade:
- https://snyk.io/vuln/SNYK-JS-AXIOS-1038255

* fix(examples): remove the body-parser module.

* When a structured formatted CloudEvent comes in, the body parser module does know how to parse it since the content type is not application/json, which resulted in an empty request body

Signed-off-by: Lucas Holmquist <lholmqui@redhat.com>

Co-authored-by: Lucas Holmquist <lholmqui@redhat.com>

examples/express-ex/index.js

@@ -1,17 +1,29 @@
 /* eslint-disable */
 
 const express = require("express");
-const { Receiver } = require("cloudevents");
+const { CloudEvent, HTTP } = require("cloudevents");
 const app = express();
-const bodyParser = require('body-parser')
-app.use(bodyParser.json())
+
+app.use((req, res, next) => {
+  let data = "";
+
+  req.setEncoding("utf8");
+  req.on("data", function (chunk) {
+    data += chunk;
+  });
+
+  req.on("end", function () {
+    req.body = data;
+    next();
+  });
+});
 
 app.post("/", (req, res) => {
   console.log("HEADERS", req.headers);
   console.log("BODY", req.body);
 
   try {
-    const event = Receiver.accept(req.headers, req.body);
+    const event = HTTP.toEvent({ headers: req.headers, body: req.body });
     // respond as an event
     const responseEventMessage = new CloudEvent({
       source: '/',

examples/express-ex/package.json

@@ -14,8 +14,7 @@
   "author": "fabiojose@gmail.com",
   "license": "Apache-2.0",
   "dependencies": {
-    "body-parser": "^1.19.0",
-    "cloudevents": "^3.1.0",
+    "cloudevents": "^4.0.0",
     "express": "^4.17.1"
   }
 }