Quick Start
One page summary on how to start using FunLess.
Install the CLI
To start hacking with FunLess, all you need is the CLI tool: fl.
You can check out the Releases page and download the most recent one based on your system (Windows is not currently supported although there is a build for it).
Here are some quick links to download it:
Extract the executable from the archive and you can start using fl.
Deploy FunLess Locally
⚠️ You need to have Docker installed for this! ⚠️
You can use the CLI tool to deploy the platform locally using Docker containers.
It uses docker compose internally so it's a hard requirement to have a recent version of Docker.
The CLI will pull and launch 4 containers, one for the Core component, one for the Worker, one for Prometheus and one for Postgres. You can remove everything using the cli again.
fl admin deploy docker up
Now that FunLess is running, you can start deploying and running functions.
Create a function
FunLess uses WebAssembly runtimes via Wasmtime to run your functions. As of now we support Rust and JavaScript, but we are working on adding more languages.
The CLI tool already handles the compiling into WebAssembly for you, so you can focus on writing your functions.
For example, let's create a new function using the fn new cli command. We will use Rust. From a folder of your choosing, run:
fl fn new hello_funless -l rust
This will download the template folder which contains the Rust and Javascript templates, and use the Rust template
to create a new project named hello. The folder hello will contain a Cargo.toml and a lib.rs with the fl_main function,
which you can fill with your code.
The template function takes a json of the form {"name": "FunLess"} and returns a {"payload": "Hello FunLess"}. You can change it to your liking.
Now you can build and deploy it to FunLess. The create subcommand will take care of both building and uploading.
fl fn create hello hello/ --language rust
The first argument of the create subcommand is the name of the function inside FunLess, the second is the path to the directory with the code. There are other commands like build that only builds the wasm file and saves it, upload that takes a wasm file and uses it to create a function in the platform. The create command is a combination of both, but after the function creation it deletes the wasm file so your pc stays clean. At last the --language is the programming language of the code.
In FunLess each function is part of a module (you can think of them as namespaces from the C family of languages, or packages).
Every FunLess instance has a default _ module, so if you don't create a new module (with the mod subcommand) and specify it when creating functions, they will be created in the _ module. You can get info about a module with its list of function with:
fl mod get _
Invoke it
Now you can invoke it. Since the function takes a json argument, you can use the -j flag to pass the JSON object with the 'name' key as input:
fl fn invoke hello -j '{"name": "FunLess"}'
If everything worked correctly, the invocation request will be received by the core component, passed to the worker componend and the wasm function will be executed. The result will be returned to the core component and then to the CLI, which will print it to the console.
Delete it
You can delete the function with:
fl fn delete hello
Cleaning up
When you are done, you can remove the containers and cleanup the dev deployment with:
fl admin docker deploy down