sam701 / zig-cli

A simple package for building command line apps in Zig

ZIG-CLI

A simple package for building command line apps in Zig.

Inspired by urfave/cli Go package.

Features

• command line arguments are parsed into zig values
• long and short options: --option1, -o
• optional = sign: --address=127.0.0.1 equals --address 127.0.0.1
• concatenated short options: -a -b -c equals -abc
• subcommands: command1 -option1 subcommand2 -option2
• multiple option values: --opt val1 --opt val2 --opt val3
• enums as option values: --opt EnumValue1
• options value can be read from environment variables with a configured prefix
• positional arguments can be mixed with options: --opt1 val1 arg1 -v
• stops option parsing after --: command -- --abc will consider --abc as a positional argument to command.
• errors on missing required options: ERROR: option 'ip' is required
• prints help with --help
• colored help messages when TTY is attached

Usage

const std = @import("std");
const cli = @import("zig-cli");

// Define a configuration structure with default values.
var config = struct {
    host: []const u8 = "localhost",
    port: u16 = undefined,
}{};

pub fn main() !void {
    var r = try cli.AppRunner.init(std.heap.page_allocator);

    // Create an App with a command named "short" that takes host and port options.
    const app = cli.App{
        .command = cli.Command{
            .name = "short",
            .options = &.{
                // Define an Option for the "host" command-line argument.
                .{
                    .long_name = "host",
                    .help = "host to listen on",
                    .value_ref = r.mkRef(&config.host),
                },

                // Define an Option for the "port" command-line argument.
                .{
                    .long_name = "port",
                    .help = "port to bind to",
                    .required = true,
                    .value_ref = r.mkRef(&config.port),
                },

            },
            .target = cli.CommandTarget{
                .action = cli.CommandAction{ .exec = run_server },
            },
        },
    };
    return r.run(&app);
}

// Action function to execute when the "short" command is invoked.
fn run_server() !void {
    // Log a debug message indicating the server is listening on the specified host and port.
    std.log.debug("server is listening on {s}:{d}", .{ config.host, config.port });
}

Using with the Zig package manager

See the standalone example in the examples folder.

Printing help

See simple.zig

$ ./zig-out/bin/simple sub1 --help
USAGE:
  abc sub1 [OPTIONS]

another awesome command

this is my awesome multiline description.
This is already line 2.
And this is line 3.

COMMANDS:
  sub2   sub2 help

OPTIONS:
  -i, --ip <IP>         this is the IP address
      --int <VALUE>     this is an int
      --bool            this is a bool
      --float <VALUE>   this is a float
  -h, --help            Prints help information

License

MIT