Skip to main content

Go Developer Guide

Research Project: Compiling Functions from the FairBlock DistributedIBE to WebAssembly (WASM)​

This document outlines the steps to compile functions from the FairBlock DistributedIBE GitHub Repository using TinyGo to WebAssembly (WASM). The goal is to convert Fairblock's cryptography functions into WASM modules. It's needed for integration fairblock with fluent network.

Prerequisites​

To compile the Golang functions into WebAssembly, you will need to install TinyGo, which supports compiling Go programs to WASM. TinyGo is a smaller version of Go designed for embedded systems and WebAssembly targets.

Installing TinyGo​

Follow the installation instructions provided in the official TinyGo documentation. TinyGo supports multiple platforms, so ensure that you select the correct installation steps for your operating system.

Compilation Steps​

Compiling to WASM​

To compile a Golang function from the FairBlock DistributedIBE repository into a .wasm file, you need to use the wasm-unknown target in TinyGo. Here is the example command that can be used for this purpose:

tinygo build -o wasm1.wasm -target=wasm-unknown github.com/FairBlock/DistributedIBE

This command will generate a wasm1.wasm file of approximately 1 MB in size. The file size may vary slightly depending on the content of the functions you are compiling and any additional dependencies.

Check result. Converting WASM to WAT​

After generating the .wasm file, you can convert it to WAT (WebAssembly Text Format) using the wasm2wat tool, which is part of the WebAssembly Binary Toolkit (WABT). The conversion is done with the following command:

wasm2wat wasm1.wasm -o wasm1.wat

The WAT format is a human-readable representation of the WebAssembly binary format and is useful for inspecting the WebAssembly code.

Adding Exported Functions in Golang​

To compile specific Golang functions to WASM using TinyGo, you need to mark the functions with a special comment. TinyGo recognizes this comment and ensures that the function will be compiled into the WASM output. The comment //export <function_name> should be placed above the function definition.

Example Golang Function with Export Comment​

Below is an example of a Golang function from the FairBlock DistributedIBE repository that includes the necessary export comment for TinyGo compilation:

//export decrypt
func decrypt() {
	message := "this is a long message with more than 32 bytes! this is a long message with more than 32 bytes!long message with more than 32 bytes! this is a long message with long message with more than 32 bytes! this is a long message with long message with more than 32 bytes! this is a long message with long message with more than 32 bytes! this is a long message with long message with more than 32 bytes! this is a long message with long message with more than 32 bytes! this is a long message with long message with more than 32 bytes! this is a long message with "
	//message = message
	var plainData bytes.Buffer
	plainData.WriteString(message)

	res, err := DistributedIBE(4, 1, "300", plainData, message)

	if res == false {
		fmt.Println(err)
	}
}

This decrypt() function will be included in the WASM output due to the //export decrypt comment. You can modify the function's behavior as necessary before compiling it to WebAssembly.

Reference​

https://github.com/fluentlabs-xyz/fluentbase/tree/devel/examples/fairblock