Add TCPMon with WSO2 MI integration diagrams and documentation

en/docs/observe-and-manage/classic-observability-tcp/message-monitoring-with-tcpmon.md

@@ -53,3 +53,164 @@ To monitor messages from client to server using TCPMon:
     windows.
 
     ![TCPMon console option]({{base_path}}/assets/img/integrate/tcp/tcp-console-options.png)
+
+ ## Using TCPMon with WSO2 Micro Integrator
+
+This section shows how to integrate TCPMon with **WSO2 Micro Integrator (MI)** so you can observe messages flowing between clients, MI, and backend services during development and troubleshooting.
+
+### Prerequisites
+
+- WSO2 Micro Integrator **4.4.0+**
+- TCPMon (Apache Axis utility)
+- Java 8+  
+- MI running locally (default HTTP port **8290**)
+
+!!! note
+    TCPMon works at the TCP level and is ideal for **HTTP** traffic during debugging.  
+    For HTTPS, either configure trusted certificates end-to-end or switch services to HTTP temporarily while you debug.
+
+---
+
+### Monitor inbound messages (Client → MI)
+
+Use TCPMon as a listener **in front of MI** so all client requests pass through it.
+
+![Monitor Inbound Messages]({{base_path}}/assets/img/integrate/tcp/Client_MI2.png)
+
+1. **Start TCPMon** and create a new listener:
+   - **Listen Port**: `8081` (any free local port)
+   - **Target Host**: `localhost`
+   - **Target Port**: `8290` (MI default HTTP port)
+
+2. **Send client requests via TCPMon**, not directly to MI.  
+
+For example, if your MI proxy is normally at:
+```
+http://localhost:8290/services/SimpleProxy
+```
+
+send requests to:
+```
+http://localhost:8081/services/SimpleProxy
+```
+
+3. Observe in TCPMon:
+- **Left pane** → incoming request from client  
+- **Right pane** → response returned by MI
+
+---
+
+### Monitor outbound messages (MI → Backend)
+
+Route MI's **endpoint** through a second TCPMon listener to capture calls MI makes to upstream/backends.
+
+![Monitor Outbound Messages]({{base_path}}/assets/img/integrate/tcp/MI_BACKEND.png)
+
+1. **Start another TCPMon** instance:
+- **Listen Port**: `8082`
+- **Target Host**: `<real-backend-host>` (e.g., `backend.example.com`)
+- **Target Port**: `<real-backend-port>` (e.g., `9000`)
+
+2. **Point your MI endpoint to TCPMon** instead of the real backend.  
+Example Proxy Service:
+```xml
+<proxy name="SimpleProxy" startOnLoad="true" transports="http">
+    <target>
+        <inSequence>
+            <log level="full"/>
+            <send>
+                <endpoint>
+                    <!-- Route via TCPMon (8082) instead of the real backend -->
+                    <address uri="http://localhost:8082/services/BackendService"/>
+                </endpoint>
+            </send>
+        </inSequence>
+        <outSequence>
+            <send/>
+        </outSequence>
+    </target>
+</proxy>
+```
+
+---
+
+### End-to-end example (both directions)
+
+The setup below shows how to monitor both inbound and outbound traffic using two TCPMon instances.
+
+![End-to-End Monitoring]({{base_path}}/assets/img/integrate/tcp/ALL.png)
+
+| Flow | Source | → | Destination | TCPMon Mapping |
+|------|----------|---|--------------|----------------|
+| Inbound | Client | → | Micro Integrator | TCPMon `8081 → 8290` |
+| Outbound | Micro Integrator | → | Backend Service | TCPMon `8082 → 9000` |
+
+1. Start TCPMon **#1**: Listen on **8081**, target **localhost:8290**  
+2. Start TCPMon **#2**: Listen on **8082**, target your backend (e.g., `backend.example.com:9000`)  
+3. Update the MI endpoint to `http://localhost:8082/...`  
+4. Send requests to `http://localhost:8081/services/SimpleProxy`
+
+**You can now view:**
+- Requests/responses between **Client ↔ MI** in TCPMon 8081  
+- Requests/responses between **MI ↔ Backend** in TCPMon 8082
+
+---
+
+### Practical Use Cases
+
+#### Use Case 1: Debugging SOAP Message Transformation
+
+![SOAP Transformation]({{base_path}}/assets/img/integrate/tcp/SOAP_Transform.png)
+
+**Scenario:** You need to verify that SOAP envelopes are correctly transformed to REST JSON before reaching the backend.
+
+**Setup:**
+- Client sends SOAP requests to TCPMon (8081)
+- TCPMon forwards to MI which transforms SOAP to REST
+- MI sends JSON to backend REST API
+- View XML format in TCPMon to debug transformation issues
+
+---
+
+#### Use Case 2: Debugging Authentication Headers
+
+![Authentication Debugging]({{base_path}}/assets/img/integrate/tcp/Auth_Debug.png)
+
+**Scenario:** Debug authentication issues by inspecting whether authorization headers are being correctly passed or modified.
+
+**Setup:**
+- Client sends requests with Authorization headers to TCPMon (8081)
+- TCPMon captures headers for inspection
+- MI may modify or add additional headers via Header Mediator
+- Backend API validates and responds with 200 OK or 401 Unauthorized
+- Verify headers are correctly passed or modified by MI
+
+---
+
+#### Use Case 3: Load Balancing & Failover Testing
+
+![Load Balancing]({{base_path}}/assets/img/integrate/tcp/Load_Balance.png)
+
+**Scenario:** Test load balancing behavior and verify requests are distributed correctly across multiple backend servers.
+
+**Setup:**
+- Client sends load test requests to TCPMon (8081)
+- TCPMon forwards to MI Load Balance Endpoint
+- MI distributes requests across Server 1 and Server 2
+- Monitor distribution to ensure proper load balancing and failover
+
+---
+
+### Tips & troubleshooting
+
+- **Port in use?** Pick any free local port for the TCPMon listener (e.g., 8083/8084).  
+- **Nothing appears in TCPMon?** Ensure your client or MI **actually targets the TCPMon port** (8081/8082).  
+- **HTTPS traffic?** Use HTTP for debugging or configure certificates so TCPMon can handle TLS.  
+- **Headers/payloads:** Enable **XML view** in TCPMon to inspect SOAP/REST bodies.
+
+---
+
+### References
+
+- [Apache TCPMon Documentation](https://ws.apache.org/tcpmon/)  
+- [WSO2 MI Docs – Message Monitoring with TCPMon](https://mi.docs.wso2.com/en/latest/observe-and-manage/classic-observability-tcp/message-monitoring-with-tcpmon/)

en/mkdocs.yml

@@ -1213,6 +1213,6 @@ extra:
       version: 1.2.0-1
       git_tag: v1.2.0.1
   site_version: 4.5.0
-  #base_path: http://localhost:8000/en/latest
+  base_path: http://localhost:8000/en/latest
   base_path: https://mi.docs.wso2.com/en/4.5.0
   envoy_path: https://www.envoyproxy.io/docs/envoy/v1.24.1