From 05f3cbfbc9b8d801252e19ad4d033bce90404ecd Mon Sep 17 00:00:00 2001
From: nitish-egov <137176807+nitish-egov@users.noreply.github.com>
Date: Wed, 18 Dec 2024 18:03:04 +0530
Subject: [PATCH] added gzip handler in middleware

---
 .../project-factory/src/server/app.ts         | 17 ++++++--
 .../src/server/utils/gzipHandler.ts           | 41 +++++++++++++++++++
 .../utils/middlewares/requestMiddleware.ts    |  8 ++--
 3 files changed, 58 insertions(+), 8 deletions(-)
 create mode 100644 health-services/project-factory/src/server/utils/gzipHandler.ts

diff --git a/health-services/project-factory/src/server/app.ts b/health-services/project-factory/src/server/app.ts
index f662b76d104..c1ca2179a3b 100644
--- a/health-services/project-factory/src/server/app.ts
+++ b/health-services/project-factory/src/server/app.ts
@@ -11,6 +11,7 @@ import { tracingMiddleware } from "./tracing";
 import { createProxyMiddleware } from "http-proxy-middleware";
 import * as v8 from "v8";
 import { logger } from "./utils/logger";
+import { handleGzipRequest } from "./utils/gzipHandler";
 
 const printMemoryInMB = (memoryInBytes: number) => {
   const memoryInMB = memoryInBytes / (1024 * 1024); // Convert bytes to MB
@@ -41,16 +42,24 @@ class App {
   }
 
   private initializeMiddlewares() {
-    this.app.use(
-      bodyParser.json({ limit: config.app.incomingRequestPayloadLimit })
-    );
+    this.app.use((req, res, next) => {
+      const contentType = req.headers["content-type"];
+
+      if (contentType === "application/gzip") {
+        return handleGzipRequest(req, res, next);
+      }
+
+      return bodyParser.json({ limit: config.app.incomingRequestPayloadLimit })(req, res, next);
+    });
+
+
     this.app.use(
       bodyParser.urlencoded({
         limit: config.app.incomingRequestPayloadLimit,
         extended: true,
       })
     );
-    this.app.use(bodyParser.json());
+    // this.app.use(bodyParser.json());
     this.app.use(tracingMiddleware);
     this.app.use(requestMiddleware);
     this.app.use(errorLogger);
diff --git a/health-services/project-factory/src/server/utils/gzipHandler.ts b/health-services/project-factory/src/server/utils/gzipHandler.ts
new file mode 100644
index 00000000000..5b40ce6a0bb
--- /dev/null
+++ b/health-services/project-factory/src/server/utils/gzipHandler.ts
@@ -0,0 +1,41 @@
+import zlib from "zlib";
+import { Request, Response, NextFunction } from "express";
+import { logger } from "./logger";
+
+export const handleGzipRequest = (
+    req: Request,
+    res: Response,
+    next: NextFunction
+) => {
+    const buffers: Buffer[] = [];
+
+    req.on("data", (chunk) => buffers.push(chunk));
+    req.on("end", () => {
+        try {
+            const gzipBuffer = Buffer.concat(buffers);
+
+            // Decompress the Gzip data
+            zlib.gunzip(gzipBuffer, (err, decompressedBuffer) => {
+                if (err) {
+                    logger.error("Error decompressing Gzip file:", err);
+                    res.status(500).send("Invalid Gzip file");
+                    return;
+                }
+
+                try {
+                    // Convert the decompressed buffer to string and parse as JSON
+                    const jsonData = decompressedBuffer.toString();
+                    const parsedData = JSON.parse(jsonData);
+                    req.body = parsedData; // Attach parsed data to the request body
+                    next(); // Proceed to next middleware
+                } catch (parseError) {
+                    logger.error("Error parsing JSON data:", parseError);
+                    res.status(500).send("Invalid JSON in Gzip content");
+                }
+            });
+        } catch (err) {
+            logger.error("Error processing Gzip content:", err);
+            res.status(500).send("Invalid Gzip content");
+        }
+    });
+};
\ No newline at end of file
diff --git a/health-services/project-factory/src/server/utils/middlewares/requestMiddleware.ts b/health-services/project-factory/src/server/utils/middlewares/requestMiddleware.ts
index a8bfd34a330..5c5c1eb32be 100644
--- a/health-services/project-factory/src/server/utils/middlewares/requestMiddleware.ts
+++ b/health-services/project-factory/src/server/utils/middlewares/requestMiddleware.ts
@@ -18,9 +18,9 @@ const requestMiddleware = (req: Request, res: Response, next: NextFunction) => {
     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;
@@ -43,4 +43,4 @@ const requestMiddleware = (req: Request, res: Response, next: NextFunction) => {
   }
 };
 
-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
\ No newline at end of file