WebSocket Tester

Tool Overview: WebSocket Tester

The WebSocket tester is a browser-based client for validating real-time services without leaving ToolMi. Supply an endpoint, connect instantly, and inspect every frame with timestamps, status updates, and direction tags.

What Is WebSocket Tester?

WebSocket Tester quickly tests rules or connections to help locate issues.

How to Use

1. Enter rules or parameters.
2. Provide sample input or a target address.
3. Review results and adjust.

Common Use Cases

• Pre-release checks and debugging
• Validate rules and edge cases
• Quick verification during integration

❓ FAQ

Q1: Results not as expected?
A: Check input and options.

Q2: Test failed?
A: Simplify the case to isolate the issue.

Q3: How to save output?
A: Copy the results or take a snapshot.

✨ Key Features

• 🔄 Live connection monitor: Track handshake progress, readyState transitions, close codes, and reasons in real time.
• 🧾 Structured message log: Each frame is recorded with timestamp, direction, and payload, with newest entries pinned to the top.
• 🧩 Binary awareness: Automatically labels binary frames so you can capture raw bytes from browser DevTools when necessary.
• ⚙️ Flexible editor workflow: Toggle auto scroll and post-send clearing to match either rapid probes or iterative payload editing.
• 🌐 Multilingual guidance: Help content stays in sync with your current locale for consistent team workflows.

🚀 Quick Start

1. Paste the target ws:// or wss:// endpoint into the Server Endpoint field.
2. Use Switch to ws:///wss:// to flip schemes without retyping the address.
3. (Optional) Enter subprotocol names separated by commas when the backend negotiates a specific protocol.
4. Click Connect and watch the status badge for handshake confirmation.
5. Write your payload in the message box and press Send Message to emit a frame.
6. Observe Sent and Received logs at the top of the panel, pausing auto scroll when you need to inspect history.

📖 Usage Examples

Echo server verification

Endpoint: wss://echo.websocket.events
Message: {"action":"ping","source":"toolmi"}

The server echoes the payload back immediately. You should see a Sent log followed by a Received log containing the same JSON text.

Subprotocol negotiation

Endpoint: wss://example.com/chat
Subprotocols: chat.v2, json
Message: {"type":"join","room":"support"}

If the server accepts chat.v2, the connection switches to that protocol and regular message exchange continues.

Iterative payload testing

1. Disable Clear message after sending.
2. Send an initial JSON document.
3. Modify only the changed fields and resend without retyping the entire payload.
4. Compare each response at the top of the log.

🎯 Application Scenarios

1. API integration debugging

Investigate WebSocket-based APIs before integrating them into your application. Validate authentication, channel subscriptions, and message shapes.

2. Real-time feature demos

Demonstrate streaming updates to stakeholders by connecting to staging services and showcasing live data flow without custom tooling.

3. Protocol education

Teach WebSocket behavior by showing how different close codes, binary frames, or subprotocols appear throughout a conversation.

📘 Log Legend

• Info – connection lifecycle messages including connect attempts, successful handshakes, disconnects, and close reasons.
• Sent – frames transmitted from the editor to the server.
• Received – frames returned by the server; text payloads display verbatim.
• Error – browser-level issues such as invalid URLs, TLS problems, or network interruptions.

🛠️ Troubleshooting

• Browsers do not allow custom headers on WebSocket handshakes. If you need authentication headers, test from the same origin or use a desktop client.
• Close code 1006 usually indicates the connection was interrupted during the handshake; inspect proxies, firewalls, or certificate settings.
• When the server rejects your connection, remove unknown subprotocols or confirm the expected protocol name with the backend team.
• If binary frames appear but you need raw bytes, open the Network tab in DevTools and save the frame contents from there.

💡 Additional Tips

• Pair the tester with the JSON formatter or JWT decoder tabs to craft payloads quickly.
• Keep auto scroll enabled for bursty streams; disable it when you need a static view for screenshots or comparisons.
• Use the scheme toggle button when switching between staging (ws://) and production (wss://) endpoints.
• Share the endpoint and payload snippet with teammates so they can reproduce the session using the same tool.