rash

Declarative shell scripting using Rust native bindings inspired by Ansible

Getting Started & Documentation

For installation and usage, see our Documentation.

Why Rash

Manage your scripts in a declarative style.

If you:

think that long bash scripts are difficult to maintain
love Ansible syntax to setup your environments

Or use it for your local scripts!

Then keep on reading.

Here is Rash!

Declarative vs imperative

Imperative: entrypoint.sh:

#!/bin/bash
set -e

REQUIRED_PARAMS="
VAULT_URL
VAULT_ROLE_ID
VAULT_SECRET_ID
VAULT_SECRET_PATH
"

for required in $REQUIRED_PARAMS ; do
  [[ -z "${!required}" ]] && echo "$required IS NOT DEFINED" && exit 1
done

echo "[$0] Logging into Vault..."
VAULT_TOKEN=$(curl -s $VAULT_URL/v1/auth/approle/login \
--data '{"role_id": "'$VAULT_ROLE_ID'","secret_id": "'$VAULT_SECRET_ID'"}' \
| jq -r .auth.client_token)

echo "[$0] Getting Samuel API key from Vault..."
export APP1_API_KEY=$(curl -s -H "X-Vault-Token: $VAULT_TOKEN" \
$VAULT_URL/v1/$VAULT_SECRET_PATH | jq -r .data.api_key)


exec "$@"

Declarative: entrypoint.rh

#!/bin/rash

- name: Verify input parameters
  assert:
    that:
      - env.VAULT_URL is defined
      - env.VAULT_ROLE_ID is defined
      - env.VAULT_SECRET_ID is defined
      - env.VAULT_SECRET_PATH is defined

- name: launch docker CMD
  command:
    cmd: { { rash.argv } }
    transfer_pid: yes
  env:
    APP1_API_KEY: "{{ lookup('vault', env.VAULT_SECRET_PATH ) }}"

Docopts

docopt implementation included:

Easy to define interfaces for command-line app.
Automatically generate a parser from doc.

Example:

#!/usr/bin/env -S rash --
#
# Copy files from source to dest dir
#
# Usage:
#   copy.rh [options] <source>... <dest>
#   copy.rh
#
# Options:
#   -h --help    show this help message and exit
#   --mode MODE  dest file permissions [default: 0644]

- copy:
    src: "{{ item }}"
    dest: "{{ dest }}/{{ item | split('/') | last }}"
    mode: "{{ options.mode }}"
  loop: "{{ source | default ([]) }}"

Lightness

All you need to run Rash is a Linux kernel!

You can use it in your favorite IoT chips running Linux or in containers from scratch!

Status

Stable API with few modules.