Function

The function command is used to interact with Scale Functions locally. fn is an alias for function.

New

To create a new Scale Function, run the following command:

scale function new <name>:<tag>

This will create a new scale function in the current directory in the Go programming language.

You can also specify the language of the function you want to create by using the --language flag:

scale function new <name>:<tag> --language <language>

The following languages are currently supported:

• go - Go
• rust - Rust
• ts - TypeScript/JavaScript

Build

The build subcommand is used to build a Scale Function using the toolchain for the Scale Function's source language. It can be run from the root of the Scale Function's directory:

scale function build

The --directory flag can be used to specify the directory of the Scale Function:

scale function build --directory <directory>

The --name, --org, and --tag flags can be used to specify the name, organization, and tag of the Scale Function at build time:

scale function build --name <name> --org <org> --tag <tag>

Because this command relies on the toolchain for the Scale Function's source language being installed on your machine, it may sometimes be necessary to tell the command where it can find the toolchain executables.

The --cargo, --go, and --tinygo flags can be used to specify the path to the cargo, go, and tinygo executables.

List

The list subcommand is used to list all the compiled Scale Functions available in the local Scale Function cache.

scale function list

If you'd like to specify the directory of the Scale Function cache, you can use the --cache-directory flag:

scale function list --cache-directory <cache-directory>

Run

You can run your compiled scale functions locally using the run subcommand. This command will start a local HTTP server that will execute the Scale Function when it receives an HTTP request.

scale function run  [ ...[ <name>:<tag> ] | [ <org>/<name>:<tag> ] ]

The --listen flag can be used to specify the address and port that the local HTTP server should listen on (by default it will listen on :8080)

It is also possible to provide multiple Scale Functions to the run subcommand. If you do, the local HTTP server will execute the Scale Functions in a chain, and will only execute the next function in the chain if the previous function calls .Next().

If the function is not available locally, the run command will attempt to look for it in the Scale Registry (if the CLI is authenticated).

Export

The export subcommand is used to export a Scale Function from the local Scale Function cache to a local .scale file.

It's helpful in situations where you want to distribute a Scale Function without using the Scale Registry, or if you want to embed it inside your Runtime or Application.

scale function export [<name>:<tag> | [<org>/<name>:<tag>] <path>

The function will be exported to the specified <path> directory as a .scale file. The --output flag can be used to override the name of the exported .scale file:

scale function export [<name>:<tag> | [<org>/<name>:<tag>] <path> --output <output>

The --raw flag can be used to export the raw WebAssembly .wasm binary instead of the .scale file:

scale function export [<name>:<tag> | [<org>/<name>:<tag>] <path> --raw

Delete

To delete a Scale Function from the local Scale Function cache, run the following command:

scale function delete [<name>:<tag> | [<org>/<name>:<tag>]