Task automation tool on steroids for developers
Overview
devrc is an easy to use task runner on steroids. It's a small and fast utility written in Rust 🦀.
It's userful for project or common routine automation such as minification, compilation, unit testing, linting and many more.
It's just single binary and you don't need to install python
, ruby
or something else.
It allows you to run tasks that are stored in YAML file named Devrcfile
. Just type command, e.g. devrc task_name_1 task_name_2 task_name_3
.
Quick introduction
There are several ways to define task. Here are general variants:
-
Simple command definition without documentation string.
task_name: echo "Hello world"
-
More complex definition with documentation string.
task_name: desc: "Task description" exec: echo "Hello world"
To run task just type command devrc TASK_NAME
, e.g.:
For more details look into usage section or examples.
Features
Lets start with an overview of features that exist in devrc:
- All tasks can be listed from the command line with documentation
- Template engine and variables interpolation are supported
- Environment variables customization
- Command line completion scripts
- devrc supports dotenv files
- Writing task commands in different languages
- Task parameters and user input
- Remote command execution
- Read
Devrcfile
contents from stdin - Global and local defined variables and environment variables
Why YAML is used?
There are many formats (e.g. TOML, Makefile, YAML, custom formats) that have been examining after many years of using Makefiles
for project routine automation.
What are the benefits of using YAML for this purpose and why it's choosen:
- YAML is designed to be human-friendly and easy to read;
- Syntax highlight works out of the box;
- YAML is used industry-wide for declarative configuration. For example, it's used by gitlab-ci, GitHub actions and ansible;
- Many text editors and platforms have plugins or built-in tools to check YAML configuration syntax for you.
- Good parsers for YAML already exist and I don't need to waste time for implementing and testing a self-written parser.
Table of contents
Installation
To install devrc
, you can download a pre-compiled binary, or you can compile it from source.
You may be able to install devrc
using your OS’s package manager, depending on your platform.
Install from crates.io
devrc
is written in Rust. You will need rustc version 1.48.0 or higher.
The recommended way to install Rust for development is from the official download page, using rustup.
If you have the Rust toolchain already installed on your local system, you can use the cargo install
command:
Cargo will build the devrc
binary and place it in $HOME/.cargo
.
Compile from sources
Clone the repository and change it to your working directory.
Binary Releases
Binary releases are available in the github releases page for macOS, and Linux targets. The following binaries are available for each release:
- x86_64-unknown-linux-musl
- x86_64-apple-darwin
Usage
Tasks are stored as mappings (hashes/dictionaries/key-value pairs) in YAML file named Devrcfile
by default.
Or you can specify environment variable DEVRC_FILE
with alternative file name.
Also you can store global tasks in ~/.devrc
in your home directory or overwrite shared project tasks or varibles by local Devrcfile.local
file.
If command line option -f
is used:
- Loading
~/.devrc
in home directory if it exists and if command line flag-g
or optiondevrc_config.global
are enabled; - Loading files which are specified by command line option
-f
;
If command line option -f
isn't used:
- Loading
~/.devrc
in home directory if it exists and if command line flag-g
or optiondevrc_config.global
inDevrcfile
are enabled; - Loading
Devrcfile
or file name which is defined by environment variableDEVRC_FILE
in the current directory; - Loading
Devrcfile.local
.
The names of the files are a case sensitive.
Task defition is like to definition of job in .gitlab-ci files. Key is used as task name and value is used to create task logic. Some key names are reserved and described below.
Task definition
There are different types of tasks.
- Executable task
- Configuration task (it hasn't been implemented yet).
There are three styles of task definition:
-
Simple command definition without documentation string.
task_name: echo "Hello world"
or several commands in one task
task_name: - echo "Hello Alex!" - echo "Hello Alice!"
-
More complex definition with documentation string and variables.
variables: name: "Alex" task_name: desc: "Task description" exec: echo "Hello {{ name }}"
or
variables: first_name: "Alex" second_name: "Alice" environment: ENV_NAME: "{{ second_name }}" task_name: desc: "Task description" exec: - echo "Hello {{ first_name }}!" - echo "Hello $ENV_NAME!"
If we write code to Devrcfile
and type command devrc task_name
in console it will output to console:
Hello Alex!
Hello Alice!
Pay attention that {{ first_name }}
are replaced by Alex
by template engine and $ENV_NAME!
are replaced by Alice
by bash.
More complex examples can be found in examples directory.
Reserved keywords
There are few reserved keywords that can't be used as task name:
devrc_config
- global options such asshell
,log_level
,current_directory
;variables
- global set of variables that are used by template engine;environment
- global set of environment variables that are passed to children process's environment;before_script
- is a task that are executed before first task;after_script
- is a task that are executed after last task;before_task
- is a task that are executed before each task;after_task
- is a task that are executed after each task;env_file
- is used for (dotenv files)[#dotenv-files-support];
Configuration
devrc_config:
global: true
interpreter: /bin/bash -c
default:
Variables
Variables are used by template engine to compute commands, another variables (global or local) or environment variables. If there exists global and local variables with the same name, then local will overwrite it's value.
Environment variables
Environment variables that are passed to children process's environment and they must be accessed using $VARIABLE_NAME in commands. Environment variables can be defined globally or locally in task. If there exists global and local environment variables with the same name, then local will overwrite it's value.
The shell will expand or substitute the value of a variable into a command line if you put a Dollar Sign $
in front of the variable name.
tast_name:
environment:
name: "Alex"
exec: Hello $name!
Dotenv files support
devrc
can load environment variables from env (dotenv) files. These variables are environment variables, not template variables. By default if something goes wrong in dotenv loading, devrc
will break and exit. You can change default behaviour by using option ignore_errors
and if something goes wrong, devrc
will continue.
If env file contains:
ENV_NAME=Alex
you can load environment varibles from files using one of variants:
env_file:
- ./.env
- file: ./.env_3
ignore_errors: true
- file: ./.env_2
task_name: echo "Hello $ENV_NAME"
File path can be absolute or relative. Part ./
substitute to current directory.
Execution and computation rules
devrc
views commands, global or local task defined variables, global or local task defines environment variables as templates. It applies template engine for commands before executing them or before variable assignment.
devrc
consistently reads variables from files and applies a template engine based on Jinja2/Django syntax.
In the example text variable_1 variable_2
is assigned to a variable var_2
and text env_var variable_1 variable_2
is assignet to an environment variable ENV_VAR
:
variables:
var_1: "variable 1"
var_2: "variable_2 {{ var_1}}"
environment:
ENV_VAR: "env_var {{ var_2 }}"
Task dependencies
Task may have dependencies from another tasks. Dependencies of a task always run before a task execution and before before_task
hook.
This is useful to make some job before given task, like clean cache, remove atrifacts, etc. Dependencies run in series.
task_1: echo "Hello world!"
task_2:
exec: echo "Hello $USER!"
deps:
Template engine
Task parameters and user input
Task may have parameters or user input.
Notice: This feature has't been implemented yet.
Here task has a required parameter name
, an optional parameter other
with default value of Alice
and host parameter host
which is assigned after user input:
task_name:
exec:
- echo "Hello {{ name }} and {{ other}}"
- curl -v {{ host }}
params:
name: required
other: "Alice"
host:
type: input
default: https://github.com
Remote command execution
It's also possible to execute task on remote hosts.
Notice: This feature has't been implemented yet.
task_name:
exec: echo "Hello {{ name }} from $(hostname)"
variables:
name: "Alex"
username: root
remote:
- "{{ username }}@hostname1:22"
- root@hostname2:22
task_name:
exec: echo "Hello {{ name }} from $(hostname)"
variables:
name: "Alex"
username: root
remote:
hosts:
- "{{ username }}@hostname1:22"
- hostname2
Writing task commands in different languages
hello_1:
desc: "Execute python script"
exec: |
#!/usr/bin/env python
print("Hello from python")
hello_2:
desc: "Execute javascript by node"
exec: |
#!/usr/bin/env node
console.log("Hello from node")
Command devrc hello_1 hello_2
output:
Hello from python
Hello from node
Read Devrcfile from stdin
Instead of reading files devrc
can read tasks file from stdin. To enable this behaviour pass --stdin
flag:
|
or
Alternatives
- Bash or makefile :-)
- just - is a handy way to save and run project-specific commands. Commands are stored in a file called justfile with syntax inspired by
make
. - robo - Simple YAML-based task runner written in Go. It looks abandoned.
- go-task - simpler Make alternative written in Go. It uses Go's template engine which syntax makes me cry.
Contributing
Any suggestion, feedback or contributing is highly appreciated.
I'm especially very thankful for your grammar correction contributions, because English isn't my native language.
Thank you for your support!