sh-art

just a piece of shcript

Developing marginally complex command line utilities using bash in a consistent manner presents challenges.

This project aims at providing a generic library facilitating that task, driven by personal needs.

Specifically, it takes care of argument parsing and validation, logging, http, string manipulation and other commodities in a consistent fashion.

TL;DR

On mac: brew install sh_art

You can then use one of the example binaries to get a taste (named dc-*).

Or start your own foobar script:

#!/usr/bin/env bash

. "$(brew --prefix)/lib/dc-sh-art"

# Information about your `foobar` script
readonly CLI_VERSION="0.0.1"
readonly CLI_LICENSE="MIT License"
readonly CLI_DESC="super top dupper awesome"

# Declare flags and arguments
dc::commander::initialize
dc::commander::declare::flag myflag "^(foo|bar)$" "a flag that does foo or bar" optional
dc::commander::declare::arg 1 "[0-9]+" "somearg" "first mandatory argument, that must be an integer"
dc::commander::boot

# State that you need the `find` binary
dc::require find

# Test if the optional flag `myflag` was set
if [ "$DC_ARGE_MYFLAG" ]; then
  dc::logger::info "Hey! You used --myflag, and the value was $DC_ARGV_MYFLAG. Did you try --help and --version as well?"
fi

# HEAD something over http
dc::logger::debug "Now, let's query something"
dc::http::request "https://www.google.com" HEAD

# Output the result
dc::logger::warning "We got something!"
dc::http::dump::body

# ... Now go do something useful (like, looking at other cli for inspiration, or reading the docs)

Requirements

Right now this is tested on:

• macOS 10.14
• Ubuntu 16.04, 18.04, 19.04, 19.10
• Debian stretch, buster, and testing
• Alpine 3.10 and edge

If that wasn't clear, this is meant to be used with bash.

Parts of the core library (dc:http) requires jq and curl, or shasum.

Library extensions require sqlite.

Specific binaries (the dc-tooling-*) may also require additional binaries like git, shellcheck, hadolint, and make.

Design principles

• emphasize use of json for cli output (you should really learn jq)
• don't pollute stdout, use stderr for all logging
• aim for correctness (eg: shellcheck), but not true POSIX-ness (too boring)

Moar

• explore some of the example clis, as one of them may turn out to be useful
• read about the core library details
• or extensions library details
• or developing sh-art

Why the name?

• it's a portementeau: "sh" (short for "shell") + "art" (short for "I like it"), which somewhat makes sense
• if it was powershell instead of bash, it would probably have been named phart, which doesn't really sound right

License