added gzip handler in middleware (#1290)

* added gzip handler in middleware

* added gzip handler specific to request middleware

* refactored gzip handler

health-services/project-factory/src/server/app.ts

@@ -50,7 +50,7 @@ class App {
         extended: true,
       })
     );
-    this.app.use(bodyParser.json());
+    // this.app.use(bodyParser.json());
     this.app.use(tracingMiddleware);
     this.app.use(requestMiddleware);
     this.app.use(errorLogger);

health-services/project-factory/src/server/utils/gzipHandler.ts

@@ -0,0 +1,36 @@
+import { Request } from "express";
+import * as zlib from "zlib";
+
+export const handleGzipRequest = async (req: Request): Promise<void> => {
+    const buffers: Buffer[] = [];
+
+    // Collect data chunks from the request
+    await new Promise<void>((resolve, reject) => {
+        req.on("data", (chunk: any) => buffers.push(chunk));
+        req.on("end", resolve);
+        req.on("error", reject);
+    });
+
+    // Concatenate and decompress the data
+    const gzipBuffer = Buffer.concat(buffers);
+    try {
+        const decompressedData = await decompressGzip(gzipBuffer);
+        req.body = decompressedData; // Assign the parsed data to req.body
+    } catch (err: any) {
+        throw new Error(`Failed to process Gzip data: ${err.message}`);
+    }
+};
+
+// Helper function to decompress Gzip data
+const decompressGzip = (gzipBuffer: Buffer): Promise<any> => {
+    return new Promise((resolve, reject) => {
+        zlib.gunzip(gzipBuffer, (err, result) => {
+            if (err) return reject(err);
+            try {
+                resolve(JSON.parse(result.toString()));
+            } catch (parseErr) {
+                reject(new Error("Invalid JSON format in decompressed data"));
+            }
+        });
+    });
+};

health-services/project-factory/src/server/utils/middlewares/requestMiddleware.ts

@@ -2,6 +2,7 @@ import { NextFunction, Request, Response } from "express"; // Importing necessar
 const { object, string } = require("yup"); // Importing object and string from yup for schema validation
 import { errorResponder } from "../genericUtils"; // Importing errorResponder function from genericUtils
 import { logger } from "../logger";
+import { handleGzipRequest } from "../gzipHandler";
 
 // Defining the request schema using yup
 const requestSchema = object({
@@ -13,18 +14,21 @@ const requestSchema = object({
 });
 
 // Middleware function to validate request payload
-const requestMiddleware = (req: Request, res: Response, next: NextFunction) => {
+const requestMiddleware = async (req: Request, res: Response, next: NextFunction) => {
   try {
     logger.info(`RECEIVED A HTTP REQUEST :: URI :: ${req.url}`);
     // Check if the content type is 'application/json'
     const contentType = req.headers['content-type'];
-    if (!contentType || !contentType.split(';').map(part => part.trim()).includes('application/json')) {
-      // If content type is not 'application/json', throw Unsupported Media Type error
-      let e: any = new Error("Unsupported Media Type: Content-Type should be 'application/json'");
+    if (!contentType || !contentType.split(';').map(part => part.trim()).includes('application/json') && !contentType.split(';').map(part => part.trim()).includes('application/gzip')) {
+      // If content type is not 'application/json' or 'application/gzip', throw Unsupported Media Type error
+      let e: any = new Error("Unsupported Media Type: Content-Type should be 'application/json' or 'application/gzip'");
       e = Object.assign(e, { status: 415, code: "UNSUPPORTED_MEDIA_TYPE" });
       errorResponder(e, req, res, 415)
       return;
     }
+    if (contentType === 'application/gzip') {
+      await handleGzipRequest(req);
+    }
     // Check if tenantId is missing in RequestInfo.userInfo
     if (!req?.body?.RequestInfo?.userInfo?.tenantId) {
       // If tenantId is missing, throw Validation Error
@@ -37,10 +41,11 @@ const requestMiddleware = (req: Request, res: Response, next: NextFunction) => {
     requestSchema.validateSync(req.body.RequestInfo);
     // If validation succeeds, proceed to the next middleware
     next();
-  } catch (error) {
+  }
+  catch (error) {
     // If an error occurs during validation process, handle the error using errorResponder function
     errorResponder(error, req, res);
   }
 };
 
-export default requestMiddleware; // Exporting the requestMiddleware function for use in Express middleware chain
+export default requestMiddleware; // Exporting the requestMiddleware function for use in Express middleware chain