Merge pull request #152 from PeerPrep/questions-service-serverless-update

Add new endpoint

Author: sivayogasubramanian

deployment/docker-compose.yml

@@ -75,6 +75,8 @@ services:
       MONGODB_URL: ${MONGODB_URL}
       BUCKET_NAME: ${BUCKET_NAME}
       USERS_SERVICE_URL: ${USERS_SERVICE_URL}
+      INITIALIZATION_VECTOR: ${INITIALIZATION_VECTOR}
+      ENCRYPTION_KEY: ${ENCRYPTION_KEY}
 
   users:
     image: ghcr.io/peerprep/peerprep-users-service:latest

questions/.env.example

@@ -2,3 +2,5 @@ MONGODB_URL=mongodb://localhost:27017/questions
 BUCKET_NAME=peerprep3219.appspot.com
 GOOGLE_APPLICATION_CREDENTIALS=./service-account.json
 USERS_SERVICE_URL=http://localhost:6969
+INITIALIZATION_VECTOR=
+ENCRYPTION_KEY=

questions/src/index.ts

@@ -1,15 +1,15 @@
-import express from "express";
 import bodyParser from "body-parser";
 import compression from "compression";
 import cors, { CorsOptions } from "cors";
+import dotenv from "dotenv";
+import express from "express";
+import { applicationDefault, initializeApp } from "firebase-admin/app";
+import { getAuth } from "firebase-admin/auth";
 import http from "http";
 import mongoose from "mongoose";
-import router from "./router";
-import { initializeApp } from "firebase-admin/app";
-import { applicationDefault } from "firebase-admin/app";
-import { getAuth } from "firebase-admin/auth";
-import getFirebaseMiddleware from "./middleware";
-import dotenv from "dotenv";
+import getFirebaseMiddleware from "./middleware/auth";
+import decryptRequestBody from "./middleware/serverless";
+import { normalRouter } from "./router";
 
 dotenv.config();
 
@@ -33,7 +33,8 @@ const app = express();
 app.use(cors(corsOptions));
 app.use(compression());
 app.use(bodyParser.json());
-app.use("/api/v1/", getFirebaseMiddleware(firebaseAuth), router());
+app.use("/api/v1/", getFirebaseMiddleware(firebaseAuth), normalRouter());
+app.use("/api/serverless", decryptRequestBody(), normalRouter());
 
 const server = http.createServer(app);
 

questions/src/middleware/index.ts renamed to questions/src/middleware/auth.ts

@@ -0,0 +1,63 @@
+import express, { NextFunction } from "express";
+import { handleServerError } from "../utils";
+import crypto from "crypto";
+
+const decryptMessage = (iv: string, key: string, ciphertext: string) => {
+  try {
+    const decipher = crypto.createDecipheriv(
+      "aes-256-cbc",
+      Buffer.from(key, "hex"),
+      Buffer.from(iv, "hex")
+    );
+    let decrypted = decipher.update(ciphertext, "hex", "utf-8");
+    decrypted += decipher.final("utf-8");
+    return decrypted;
+  } catch (error) {
+    return null;
+  }
+};
+
+const decryptRequestBody = () => {
+  return async (
+    req: express.Request,
+    res: express.Response,
+    next: NextFunction
+  ) => {
+    try {
+      const iv = process.env.INITIALIZATION_VECTOR;
+      const key = process.env.ENCRYPTION_KEY;
+      const ciphertext = req.body;
+
+      if (!key) {
+        handleServerError(new Error("No encryption key provided"), res);
+        return;
+      }
+
+      if (!iv) {
+        handleServerError(new Error("No initialization vector provided"), res);
+        return;
+      }
+
+      if (!ciphertext) {
+        handleServerError(new Error("No request body provided"), res);
+        return;
+      }
+
+      const decryptedMsg = decryptMessage(iv, key, ciphertext);
+      if (!decryptedMsg) {
+        handleServerError(new Error("Unable to decrypt request body"), res);
+        return;
+      }
+
+      req.body = JSON.parse(decryptedMsg);
+
+      next();
+      return;
+    } catch (err: any) {
+      handleServerError(err, res);
+      return;
+    }
+  };
+};
+
+export default decryptRequestBody;

questions/src/middleware/serverless.ts

@@ -1,9 +1,14 @@
 import express from "express";
-import questions from "./questions";
+import { questions, serverlessQuestions } from "./questions";
 
 const router = express.Router();
 
-export default (): express.Router => {
+export const normalRouter = (): express.Router => {
   questions(router);
   return router;
 };
+
+export const serverlessRouter = (): express.Router => {
+  serverlessQuestions(router);
+  return router;
+};

questions/src/router/index.ts

@@ -8,11 +8,15 @@ import {
   updateQuestion,
 } from "../controllers/questions";
 
-export default (router: express.Router) => {
+export const questions = (router: express.Router) => {
   router.get("/questions", getAllQuestions);
   router.get("/questions/:id", getQuestion);
   router.get("/questions/group/:ids", getQuestionsByGroupOfIds);
   router.post("/questions", createQuestion);
   router.put("/questions/:id", updateQuestion);
   router.delete("/questions/:id", deleteQuestion);
 };
+
+export const serverlessQuestions = (router: express.Router) => {
+  router.post("/questions", createQuestion);
+};