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Capsule Module SDK

What's new?

  • v0.0.6: 🐞 Redis fix
  • v0.0.5: ✨ Add 2 new helpers: GetHeaders (transform a JSON string to a map[string]string) and SetHeaders (transform a map[string]string to a JSON string)
  • v0.0.4: ✨ Add the Success and Failure functions (public functions to call success and failure) and the StringifyHTTPResponse function
  • v0.0.3: ✨ Encode retValue.TextBody to avoid special characters in jsonString
  • v0.0.2: ✨ Redis support
  • v0.0.1: 🎉 first release

What is the Capsule Module SDK alias Capsule MDK?

Capsule MDK is a WASM SDK to develop WASM modules for the Capsule applications.

The Capsule WASM modules are developed in GoLang and compiled with TinyGo 💜 (with the WASI specification)

Capsule applications?

A Capsule application is a WebAssembly Module(or Function) Runner. Right now, it exists two kind of Capsule application:

  • capsule-cli, CLI. With capsule-cli, you can simply execute a WebAssembly Capsule module in a terminal
  • capsule-http, an HTTP server that serves WebAssembly Capsule modules

Good to know

  • 🖐 you can develop your own Capsule application with Capsule Host SDK (alias Capsule HDK).
  • 🤗 a capsule application is "small" (capsule-http weighs 12M)
  • 🐳 a Capsule application is statically compiled: you can easily run it in a Distroless Docker container.
  • 💜 The Capsule applications are developed with GoLang and thanks to the Wazero project

What does a WASM Capsule function look like?

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package main

import (
    capsule "github.com/bots-garden/capsule-module-sdk"
)

func main() {
    // define wich function to run
    capsule.SetHandle(Handle)
}

// Handle function
func Handle(params []byte) ([]byte, error) {
    name := string(params)
    message := "👋 Hello " + name

    return []byte(message), nil
}

What are the added values of a Capsule application?

A Capsule application brings superpowers to the WASM Capsule modules with host functions. Thanks to these host functions, a WASM Capsule module can, for example, prints a message, reads files, writes to files, makes HTTP requests, ... See the host functions section.

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