WAZEMMES

What is this project?

We needed a WASM module for Caddy and made it proxy agnostic, so you can use it as an HTTP middleware in your projects.

How to build

Make sure you have already installed:

• go
• tinygo
• xcaddy After all requirements done, just run

make build caddy run-caddy

Explanations:

• build: compile the demo WASM plugin (located in the wasm directory)
• caddy: compile a new caddy instance using xcaddy
• run-caddy: run your fresh caddy instance

Caddyfile

You have to tell to your instance to use the WASM middleware in the Caddyfile. To do that, you can take your inspiration from this Caddyfile:

localhost {
    wasm {
        item {
            filepath ../relative/plugin.wasm
            configuration {
                # The configuration your WASM plugin expects.
                body_response "Bonjour! 🥖"
            }
        }
        item {
            filepath /another/path/to/your.wasm
            configuration {
                # The configuration your WASM plugin expects.
                body_response "Hello middleware!"
            }
        }
    }

    respond "Hello world!"
}

Configuration

This module allows you to chain multiple middlewares, you just have to define one or more item in the Caddyfile. For each item you have to pass the filepath that is the path to the compiled WASM plugin, and a configuration that is a free shape.

wasm {
    item {
        filepath first.wasm
        configuration {
            my_key my_value
        }
    }
    item {
        filepath second.wasm
    }
}

Under the hood, this middleware uses a pool to be memory efficient and you are able to configure it through the Caddyfile using the pool directive. Refers to the configuration from github.com/jolestar/go-commons-pool to learn more about the keys.

wasm {
    pool {
        LIFO false
        TestOnCreate false
        TestOnBorrow false
        TestOnReturn false
        TestWhileIdle false
        BlockWhenExhausted false
        MaxTotal 1000
        MaxIdle 1000
        MinIdle 1000
        NumTestsPerEvictionRun 1000
        MinEvictableIdleTime 10s
        SoftMinEvictableIdleTime 10s
        TimeBetweenEvictionRuns 10s
    }
}