WebSocket proxy gateway

This recipe is a proxy gateway for WebSocket end points.

Installation

• Install Go
• Download the mashling-gateway binary for respective OS from Mashling
• Install gorilla websocket go library

go get github.com/gorilla/websocket

Setup

git clone https://github.com/TIBCOSoftware/mashling-recipes
cd mashling-recipes/recipes/proxy-websocket

Place the downloaded mashling-gateway binary in proxy-websocket folder.

Testing

Start the gateway:

./mashling-gateway -c proxy-websocket.json

Start the echo WebSocket server:

go run main.go -server

#1 Streaming through the gateway

Run the client:

go run main.go -client -name=CLIENT -url=ws://localhost:9096/ws

Now you should see client is able to send & receive WebSocket messages from echo server through the proxy gateway.

#2 Limit number of concurrent connections

Run 2nd client:

go run main.go -client -name=CLIENT2 -url=ws://localhost:9096/ws

Run 3rd client:

go run main.go -client -name=CLIENT3 -url=ws://localhost:9096/ws

Now you should see that gateway rejecting 3rd client connection.

Note: You can change maximum allowed concurrent connections using maxConnections service setting.

#3 Secure websocket proxy gateway with Basic Authentication

Note that the gateway can be secured by adding the below basicauth setting in gateway->triggers->settings section.

"basicAuthFile": "${env.BASIC_AUTH_FILE}"

1. Start the microgateway with the BASIC_AUTH_FILE set to the full path to where your password file is located. The password file can be of the following form:

Plain (username:password)

foo:bar
tom:jerry

Hashed using SHA256 (username:salt:hashed)

foo:5VvmQnTXZ10wGZu_Gkjb8umfUPIOQTQ3p1YFadAWTl8=:6267beb3f851b7fee14011f6aa236556f35b186a6791b80b48341e990c367643

Start the gateway:

export BASIC_AUTH_FILE=/path/to/password.txt
./mashling-gateway -c proxy-websocket.json

2. Run the client with basicauth credentials:

go run main.go -client -url=ws://localhost:9096/ws -basicauth=foo:bar

Note that client fails to establish websocket connection when wrong credentials are supplied.