mruby-bin-barista

A ruby build tool to execute a dependency graph of tasks

NOTE: this project is beta. Actively accepting feedback and contributions.

features:

• file tracking
• argument handling and recipes for common arguments
• rudiumentary handling for local and remote imports

about

I originally made this project to handle processing separate mruby projects with more flexibility but a consistent compilation environment. I have since moved it into a more generic build system.

running barista <target> in a directory will try to locate a Brewfile which describes a dependency graph of tasks.

an example:

# declare a project spec
spec("new-barista-project") do |config|
  # define a task
  #
  # arguments paseed to this task via the cli will be reachable from the task.
  task "grind" do |args| 
    # the build method will be invoked when running the task
    def build
      # run arbitrary commands using helper methods and any cli arguments
      # this task writes to `beans.txt`
      command("echo 'grind #{args[:type] || 'arabica'} beans' > beans.txt")
    end
  end

  # another task which produces a file
  task "milk" do |args|
    def build
      command("echo 'steaming milk'")
      command("echo 'milk steamed!' > milk.txt")
    end
  end
  
  # a task with dependencies
  task "brew" do |args|
    # depends on the milk task
    #
    # if milk.txt changes, rerun the milk task
    dependency "milk" do
      files "milk.txt"
    end   

    # if beans.txt changes, rerun the grind task
    dependency "grind" do
      files "beans.txt"  
    end
 
    # wrap it up
    def build
      (args[:times] || 1).times do
        command("echo 'drip drip drip'")
      end

      command("echo 'all done!!'")
    end  
  end

  # remove produced files
  task "clean" do |args|
    def build
      command("rm -rf milk.txt && rm -rf beans.txt")
    end
  end
end

running barista brew will produce the following output.

new-barista-project run started
new-barista-project::milk started
new-barista-project::milk - running command: echo 'steaming milk'
new-barista-project::grind started
new-barista-project::grind - running command: echo 'grind arabica beans' > beans.txt
new-barista-project::milk - steaming milk
new-barista-project::milk - running command: echo 'milk steamed!' > milk.txt
new-barista-project::grind did the damn thing
new-barista-project::milk did the damn thing
new-barista-project::brew started
new-barista-project::brew - running command: echo 'drip drip drip'
new-barista-project::brew - drip drip drip
new-barista-project::brew - running command: echo 'all done!!'
new-barista-project::brew - all done!!
new-barista-project::brew did the damn thing

running barista brew again will produce the following output

new-barista-project run started
new-barista-project::brew started
new-barista-project::brew - running command: echo 'drip drip drip'
new-barista-project::brew - drip drip drip
new-barista-project::brew - running command: echo 'all done!!'
new-barista-project::brew - all done!!
new-barista-project::brew did the damn thing

touch beans.txt && barista brew

new-barista-project run started
new-barista-project::grind started
new-barista-project::grind - running command: echo 'grind arabica beans' > beans.txt
new-barista-project::grind did the damn thing
new-barista-project::brew started
new-barista-project::brew - running command: echo 'drip drip drip'
new-barista-project::brew - drip drip drip
new-barista-project::brew - running command: echo 'all done!!'
new-barista-project::brew - all done!!
new-barista-project::brew did the damn thing

arguments

pass arguments to the task with the following syntax

barista task:key=value:float=1.0:int=4:bool=true

Let's try it

barista brew:times=2

new-barista-project run started
new-barista-project::brew started
new-barista-project::brew - running command: echo 'drip drip drip'
new-barista-project::brew - drip drip drip
new-barista-project::brew - running command: echo 'drip drip drip'
new-barista-project::brew - drip drip drip
new-barista-project::brew - running command: echo 'all done!!'
new-barista-project::brew - all done!!
new-barista-project::brew did the damn thing

groups

Each task in a Brewfile will receive its own arguments.

barista brew:times=2 grind:type=robusta

Arguments can be grouped for multiple tasks by delimiting the tasks with a comma ,

barista brew,grind:times=2:type=robusta

recipes

Remembering all the permutations of arguments can be cumbersome, so the Brewfile can describe common recipes

spec("new-barista-project") do |config|
  recipe "strong", "brew:times=2"
  recipe "popular", "brew,grind:times=1:type=liberica"

  # ...
end

The recipe can now be invoked as barista @popular

imports (wip)

an rough idea is to resolve imports via git/http/filesystem

spec("barista-project") do
  # fetch and run the Brewfile in this project
  import github: "skinnyjames/some-other-barista-project"

  #....
end

It currently is tested with local file paths and will run all the tasks in the imported project.

dependencies

To build barista, you need ruby, and build tools such as a c compiler/make/git

Barista is built on mruby and should be portable once built.

installation

ruby setup.rb to build and run tests

The barista binary will be located in ./tmp/mruby/build/host/bin/barista

goals

• implementing portable commands
• more robust imports
  • checksum handling and git fetching via bundled libgit2
• safer evaluation of code (don't run untrusted Brewfile!)
• more dependency resolvers (change in environment, or change in user defined values)

contributing

This is in POC phase, so I'd love feedback. There are currently a lot of unhandled edge cases, but feel free to make an issue.

If you have ideas please also make an issue!

gratitude

Massive thanks to HellRok and the Taylor project for the beautiful build scripts.