✨ Starlet - Supercharging Starlark, Simply

Enhancing your Starlark scripting experience with powerful extensions and enriched wrappers. Start your Starlark journey with Starlet, where simplicity meets functionality.

Starlet is yet another Go wrapper for the official Starlark in Go project, designed to enhance the Starlark scripting experience with powerful extensions and enriched wrappers, and provide a more user-friendly and powerful interface for embedding Starlark scripting in your Go applications.

Inspired by the Starlight and Starlib projects, Starlet focuses on three main objectives: providing an easier-to-use Go wrapper for Starlark, offering flexible data conversion between Go and Starlark, and supplying a set of useful libraries for Starlark.

Key Features

Starlet provides the following key features:

Flexible Machine Abstraction

Starlet introduces a streamlined interface for executing Starlark scripts, encapsulating the complexities of setting up and running the scripts: The Machine type serves as a comprehensive wrapper for Starlark runtime environments, offering an intuitive API for executing Starlark scripts, managing global variables, loading modules, controlling the script execution flow., and handling script outputs.

Enhanced Data Conversion

Starlet offers the dataconv package that simplifies the data exchange between Go and Starlark types. Unlike Starlight, which wraps Go values in Starlark-friendly structures, it focuses on transforming Go values into their Starlark equivalents and vice versa. This allows for a more seamless integration of Go's rich data types into Starlark scripts.

Extended Libraries & Functionalities

Starlet includes a set of custom modules and libraries that extend the functionality of the Starlark language. These modules cover a wide range of use cases, such as file manipulation, HTTP client, JSON/CSV handling, and more, making Starlark scripts even more powerful and versatile.

Libraries

Starlet comes with a set of libraries to extend the standard Starlark library. Here's a brief overview:

Package	Go Doc	Description
atom		Atomic operations for integers, floats, and strings
base64		Base64 encoding & decoding functions
csv		Parses and writes comma-separated values (csv) contents
file		Functions to interact with the file system
goidiomatic		Go idiomatic functions and values for Starlark
hashlib		Hash primitives for Starlark
http		HTTP client and server handler implementation for Starlark
json		Utilities for converting Starlark values to/from JSON strings
log		Functionality for logging messages at various severity levels
path		Functions to manipulate directories and file paths
random		Functions to generate random values for various distributions
re		Regular expression functions for Starlark
runtime		Provides Go and app runtime information
string		Constants and functions to manipulate strings

For extensive documentation on each library, please refer to the respective README files in the lib directory. Additionally, Starlet includes an array of official modules. You can explore all provided modules by using GetAllBuiltinModuleNames() method.

Installation

To install Starlet, use the following Go command under your project directory:

go get github.com/1set/starlet

To explore the capabilities of the Starlet CLI tool, use the command below to install:

go install github.com/1set/starlet/cmd/starlet@latest

Usage

You can use Starlet to enhance your Starlark scripting experience. Here's a quick example:

import "github.com/1set/starlet"

// Define your machine with global variables and modules
globals := starlet.StringAnyMap{
    "greet": func(name string) string {
        return fmt.Sprintf("Hello, %s!", name)
    },
}
mac := starlet.NewWithNames(globals, []string{"random"}, nil)

// Run a Starlark script in the machine
script := `
target = random.choice(["World", "Starlark", "Starlet"])
text = greet(target)
print("Starlark:", text)
`
res, err := mac.RunScript([]byte(script), nil)

// Check for errors and results
if err != nil {
    fmt.Println("Error executing script:", err)
    return
}
fmt.Println("Go:", res["text"].(string))
fmt.Println("Modules:", starlet.GetAllBuiltinModuleNames())

This may output:

Starlark: Hello, Starlet!
Go: Hello, Starlet!
Modules: [atom base64 csv file go_idiomatic hashlib http json log math path random re runtime string struct time]

Use CLI to interact with the read-eval-print loop (REPL):

>>> resp = http.get("https://api.github.com/repos/1set/starlet")
>>> resp.status_code
200
>>> data = resp.json()
>>> data["description"]
"✨ Enhancing your Starlark scripting experience with powerful extensions and enriched wrappers. Start your Starlark journey with Starlet, where simplicity meets functionality."
>>> ",".join(data["topics"])
"go,golang,script,scripting,scripting-language,starlark,starlark-go,starlark-lang,starlark-language,starlarky"
>>> pprint(data["license"])
{
    "key": "mit",
    "name": "MIT License",
    "node_id": "MDc6TGljZW5zZTEz",
    "spdx_id": "MIT",
    "url": "https://api.github.com/licenses/mit"
}
>>>

Contributing

Contributions to Starlet are all welcomed. If you encounter any issues or have suggestions for improvements, please feel free to open an issue or submit a pull request. Before undertaking any significant changes, please let us know by filing an issue or claiming an existing one to ensure there is no duplication of effort.

License

Starlet is licensed under the MIT License.

Credits

Starlet is inspired by two projects:

1. Starlight: A Go wrapper and data conversion tool between Go and Starlark.
2. Starlib: A collection of third-party libraries for Starlark.

We appreciate the work done by the creators and contributors of these projects. Their efforts have paved the way for the development of Starlet. Special thanks to the authors and contributors of these projects! 🎉