From 8fc2f93e947e2c232cf3c6b68bd30ba01fb13327 Mon Sep 17 00:00:00 2001
From: Simon Larsen <simonlarsen@oneuptime.com>
Date: Tue, 10 Oct 2023 14:51:59 +0100
Subject: [PATCH] refactor otel middleware

---
 CommonServer/Utils/StartServer.ts | 35 ++++++++------
 Ingestor/API/OTelIngest.ts        | 76 +++++++++++++------------------
 2 files changed, 52 insertions(+), 59 deletions(-)

diff --git a/CommonServer/Utils/StartServer.ts b/CommonServer/Utils/StartServer.ts
index cc597791c8..9a89acee68 100644
--- a/CommonServer/Utils/StartServer.ts
+++ b/CommonServer/Utils/StartServer.ts
@@ -33,7 +33,7 @@ import { DashboardApiRoute } from 'Common/ServiceRoute';
 import HTTPResponse from 'Common/Types/API/HTTPResponse';
 import HTTPErrorResponse from 'Common/Types/API/HTTPErrorResponse';
 import ServerException from 'Common/Types/Exception/ServerException';
-// import zlib from 'zlib';
+import zlib from 'zlib';
 // import OpenTelemetrySDK from "./OpenTelemetry";
 
 const app: ExpressApplication = Express.getExpressApp();
@@ -99,25 +99,32 @@ app.use(setDefaultHeaders);
 
 app.use(function (req, res, next) {
     if (req.headers['content-encoding'] === 'gzip') {
-        // var gunzip = zlib.createGunzip();
-        // req.pipe(gunzip);
-        // var buffer: any = [];
-        // gunzip.on('data', function (data) {
-        //     buffer.push(data.toString());
-        // }).on('end', function () {
-        //     req.body = buffer.join('');
-        //     next();
-        // }).on('error', function (e) {
-        //     next(e);
-        // });
-        next();
+        let buffers: any = [];
+
+        req.on('data', (chunk) => {
+            buffers.push(chunk);
+        });
+
+        req.on('end', () => {
+            let buffer = Buffer.concat(buffers);
+            zlib.gunzip(buffer, (err, decoded) => {
+                if (err) {
+                    logger.error(err);
+                    return Response.sendErrorResponse(req, res, new ServerException("Error decompressing data"));
+                }
+
+                req.body = decoded;
+
+                next();
+            });
+        });
     } else {
         jsonBodyParserMiddleware(req, res, next);
     }
 });
 
 app.use(function (req, res, next) {
-    
+
     if (req.headers['content-encoding'] === 'gzip') {
         next();
     } else {
diff --git a/Ingestor/API/OTelIngest.ts b/Ingestor/API/OTelIngest.ts
index 6f2a347cb8..320f1b9a7b 100644
--- a/Ingestor/API/OTelIngest.ts
+++ b/Ingestor/API/OTelIngest.ts
@@ -7,7 +7,7 @@ import Express, {
 import Response from 'CommonServer/Utils/Response';
 import logger from 'CommonServer/Utils/Logger';
 import protobuf from 'protobufjs';
-import zlib from 'zlib';
+
 // Load proto file for OTel
 
 // Create a root namespace
@@ -23,6 +23,33 @@ const MetricsData = MetricsProto.lookupType('MetricsData');
 
 const router: ExpressRouter = Express.getRouter();
 
+/** 
+ *  
+ *  Otel Middleware
+ * 
+ */
+router.use('/otel/*', (req: ExpressRequest, _res: ExpressResponse, next: NextFunction) => {
+    try {
+
+        if (req.baseUrl === '/otel/v1/traces') {
+            req.body = TracesData.decode(req.body);
+        }
+
+        if (req.baseUrl === '/otel/v1/logs') {
+            req.body = LogsData.decode(req.body);
+        }
+
+        if (req.baseUrl === '/otel/v1/metrics') {
+            req.body = MetricsData.decode(req.body);
+        }
+
+        next();
+
+    } catch (err) {
+        return next(err);
+    }
+});
+
 router.post(
     '/otel/*',
     async (
@@ -31,52 +58,11 @@ router.post(
         next: NextFunction
     ): Promise<void> => {
         try {
+            logger.info('OTel Ingestor API called');
 
-            let buffers: any = [];
-            req.on('data', (chunk) => {
-                buffers.push(chunk);
-            });
+            logger.info(req.body);
 
-
-            req.on('end', () => {
-                let buffer = Buffer.concat(buffers);
-                zlib.gunzip(buffer, (err, decoded) => {
-                    if (err) {
-                        console.error(err);
-                        res.status(500).send('Error decompressing data');
-                        return;
-                    }
-
-
-                    if (req.url === '/otel/v1/traces') {
-                        const traces = TracesData.decode(decoded);
-        
-                        logger.info('Traces: ', traces);
-                    }
-        
-                    if (req.url === '/otel/v1/logs') {
-                        const logs = LogsData.decode(decoded);
-        
-                        logger.info('Logs: ', logs);
-                    }
-        
-                    if (req.url === '/otel/v1/metrics') {
-                        const metrics = MetricsData.decode(decoded);
-        
-                        logger.info('Metrics: ', metrics);
-                    }
-        
-                    // middleware marks the probe as alive.
-                    // so we don't need to do anything here.
-                    return Response.sendEmptyResponse(req, res);
-        
-                    
-                });
-            });
-
-            logger.info('OTelIngest URL: ', req.url);
-
-            
+            return Response.sendEmptyResponse(req, res);
         } catch (err) {
             return next(err);
         }