WebMocket

Websocket server for testing and development.

• Send custom messages to a client.
• Record messages sent by client.

I needed this for e2e and integration testing a bot that listened on a websocket.

webmocket

1. Start the webmocket webserver. ```bash RUST_LOG=info cargo run

   2022-09-15T14:38:07Z INFO webmocket] Listening on 127.0.0.1:3000

   ```

2. Connect a websocket client (webpage, bot, client, etc.). e.g. wscat. Then send a few messages to the server. Typically this would be the subject under test. ```bash wscat --connect http://127.0.0.1:3000/ws

   Connected (press CTRL-C to quit)

   > hello, this is the first message

   > my name is Foo and I am a Bar

   > { "message": "this would be JSON" }

   ```

3. Check messages received from client: ```bash curl http://127.0.0.1:3000/messages | jq

   [

   "hello, this is the first message",

   "my name is Foo and I am a Bar",

   "{ \"message\": \"this would be JSON\" }"

   ]

   ```

4. Fire websocket messages to the client using a normal HTTP library. e.g. curl. wscat --connect http://127.0.0.1:3000/ws curl -X POST -H"Content-type: text/plain; charset=UTF-8" \ --data 'Hello from the server 👋' \ http://127.0.0.1:3000/messages We should see wscat print the message to the console.

Install

In order to install the platform on development machine, run

cargo install webmocket

TODO: build binaries and make the avaiable for download.

Run

webmocket

Configure

Webmocket is configured through env vars. These must be set before starting.

| var | | default | |---------|----------|---------| | WEBMOCKET_ADDR | IP address of the listening host. Must be a valid IPV4 | 127.0.0.1 | | WEBMOCKET_PORT | Port on which the service will listen. Must be a valid unix port | 3000 | | WEBMOCKET_WS_PATH | Path on which the websocket can be connected. Must start with / | /ws |

E.g. to set all variables, one could run: bash WEBMOCKET_ADDR=127.0.0.2 WEBMOCKET_PORT=8080 WEBMOCKET_WS_PATH="/messages/user" RUST_LOG=info cargo run

Test

Get the source-code, then

cargo test

This builds the application and runs the tests locally.

Release

TODO: CI/CD setup

Deploy

TODO: CI/CD setup

Limitations

The service is intended for local development or tests (A CI server or such): it keeps its database in memory. This means that if you're going to send a lot of data to it, it will need a lot of memory.

The service does not bind to HTTPS (or SSL), because that is hard to achieve. if the client insists on SSL only, you may need to configure some proxy before it.

TODO

If needs arise, or pull-requests arrive, some additional features could be added:

• [ ] Proxy to an actual websocket and record messages as they would be sent server to client.
• [ ] Proxy to an actual websocket and record messages as they would be sent client to server.
• [ ] Store these recorded messages VCR style (though not nessecarily that format).
• [ ] Send those recorded server-to-client messages to a client on-demand.
• [ ] Set expectations on recorded client-to-server messages, to match that client sends what is expected.