mingling 0.1.8

A Rust CLI framework for many subcmds & complex workflows, reduces boilerplate via proc macros, focus on biz logic
Documentation

[!WARNING]

Note: Mingling is still under active development, and its API may change. Feel free to try it out and give us feedback! Hint: This note will be removed in version 0.5.0

πŸ“š Contents

πŸš€ Intro

Mingling is a proc-macro and type system-based Rust CLI framework, suitable for developing complex command-line programs with numerous subcommands.

BTW: Its name comes from the Chinese Pinyin "mΓ¬ng lΓ¬ng", meaning "Command". πŸ˜„

⚑ Quick Start

To use a release version of Mingling, get the latest version from crates.io

To use the latest version, pull the project from the main branch on github

If you have cargo-generate installed, you can quickly generate a new project template:

cargo generate --git catilgrass/mingling-template

Otherwise, add Mingling to your Cargo.toml:

# From crates.io

mingling = "0.1.8"



# From GitHub

mingling = { git = "https://github.com/catilgrass/mingling", branch = "main" }

The example below shows how to use Mingling to create a simple CLI program:

use mingling::macros::{dispatcher, gen_program, r_println, renderer};

fn main() {
    let mut program = ThisProgram::new();
    program.with_dispatcher(HelloCommand);

    // Execute
    program.exec();
}

// Define command: "<bin> hello"
dispatcher!("hello", HelloCommand => HelloEntry);

// Render HelloEntry
#[renderer]
fn render_hello_world(_prev: HelloEntry) {
    r_println!("Hello, World!")
}

// Fallbacks
#[renderer]
fn fallback_dispatcher_not_found(prev: DispatcherNotFound) {
    r_println!("Dispatcher not found for command `{}`", prev.join(", "))
}

#[renderer]
fn fallback_renderer_not_found(prev: RendererNotFound) {
    r_println!("Renderer not found `{}`", *prev)
}

// Collect renderers and chains to generate ThisProgram
gen_program!();

Output:

> mycmd hello
Hello, World!
> mycmd hallo
Dispatcher not found for command `hallo`

Now, let's see the full usage of Mingling: The following example shows how to use Mingling to create a complete CLI program with help, completion, fallback, and parser features:

use mingling::{
    ShellContext, Suggest,
    macros::{
        chain, completion, dispatcher, gen_program, help, pack, r_println, renderer, suggest,
    },
    parser::AsPicker,
    setup::BasicProgramSetup,
};

fn main() {
    // Initialize program
    let mut program = ThisProgram::new();

    // Load plugins
    program.with_setup(BasicProgramSetup);
    program.with_dispatcher(CompletionDispatcher);

    // Load commands
    program.with_dispatcher(GreetCommand);

    // Run program
    program.exec();
}

// Define dispatcher `greet`
dispatcher!("greet", GreetCommand => GreetEntry);

// Define intermediate type `StateGreeting`
pack!(StateGreeting = String);

// Define `greet` command help
#[help]
fn help_greet_command(_prev: GreetEntry) {
    r_println!("Usage: greet <NAME>");
}

// Define `greet` command completion
#[completion(GreetEntry)]
fn comp_greet_command(ctx: &ShellContext) -> Suggest {
    if ctx.previous_word == "greet" {
        return suggest! {
            "Alice",
            "Bob",
            "Peter"
        };
    }
    return suggest!();
}

// Define chain, parsing `GreetEntry` into `StateGreeting`
#[chain]
fn parse_name_to_greet(prev: GreetEntry) -> Next {
    let state_greeting: StateGreeting = 
        prev.pick_or::<String>((), "World").unpack().into();
    state_greeting
}

// Render `StateGreeting`
#[renderer]
fn render_state_greeting(prev: StateGreeting) {
    r_println!("Hello, {}!", *prev);
}

// Define fallback logic when no matching dispatcher is found
#[renderer]
fn fallback_no_dispatcher_found(prev: DispatcherNotFound) {
    r_println!("Command \"{}\" not found.", prev.join(" "));
}

// Generate program
gen_program!();

Output:

~> mycmd greet
   Hello, World!
~> mycmd greet Alice
   Hello, Alice!
~> mycmd greet --help
   Usage: greet <NAME>
~> mycmd great
   Command "great" not found.

🧠 Core Concepts

Mingling abstracts command execution into the following parts:

  1. Dispatcher - Routes user input to a specific renderer or chain based on the command node name.
  2. Chain - Transforms the incoming type into another type, passing it to the next chain or renderer.
  3. Renderer - Stops the chain and prints the currently processed type to the terminal.
  4. Program - Manages the lifecycle and configuration of the entire CLI application.

πŸ—οΈ Project Structure

The Mingling project consists of two main parts:

  • mingling/ - The core runtime library, containing type definitions, error handling, and basic functionality.
  • mingling_macros/ - The procedural macro library, providing declarative macros to simplify development.

πŸ’‘ Example Projects

πŸ‘£ Next Steps

You can read the following docs to learn more about the Mingling framework:

πŸ—ΊοΈ Roadmap

  • Milestone.1

    • [0.1.4] [core] [general_renderer] Mingling can render data into serializable formats via --json and --yaml flags
    • [0.1.5] [core] [comp] Mingling can dynamically invoke itself to provide completions for shells like bash, zsh, fish, and pwsh
    • [0.1.6] [core] [comp] Mingling can gather more context for smarter completions
    • [0.1.7] [clap] Provides a Clap compatibility layer, allowing Mingling to reuse its powerful parsing capabilities
    • [0.1.7] [core] Mingling can intercept -h or --help flags to display custom help text for each subcommand
    • [0.1.7] [mling] Provides a basic scaffolding tool (mling) for rapid development and debugging
    • [0.1.8] [core] [dispatch_tree] Converts the subcommand list into a prefix tree to improve command matching speed
    • [0.1.9] [core] [dev_toolkits] Provides debugging interfaces for developers to capture invocation information when issues arise (InvokeStackDisplay)
    • [0.1.9] [core] [repl] Provides REPL capability (program.exec_repl();)
  • Milestone.2

    • ...
    • [0.2.5] [mling] Helpdoc Maker

🚫 Unplanned Features

While Mingling has several common CLI features that are NOT PLANNED to be directly included in the framework. This is because the Rust ecosystem already has excellent and mature crates to handle these issues, and Mingling's design is intended to be used in combination with them.

  • Colored Output: To add color and styles (bold, italic, etc.) to terminal output, consider using crates like colored or owo-colors. You can integrate their types directly into your renderers.
  • I18n: To translate your CLI application, the rust-i18n crate provides a powerful internationalization solution that you can use in your command logic and renderers.
  • Progress Bars: To display progress indicators, the indicatif crate is the standard choice.
  • TUI: To build full-screen interactive terminal applications, it is recommended to use a framework like ratatui (formerly tui-rs).

πŸ“„ License

This project is licensed under the MIT License.

See LICENSE-MIT or LICENSE-APACHE file for details.