nesteduniqpairs.rb

# Get all the unique command/argument pairs inside a hash of hashes of arrays of hashes.

# Example
extras={
  stage1:{
    job1:[
      {
        command: "cmd1",
        argument: "arg1",
        otherstuff: "foo"
      },
      {
        command: "cmd1.1",
        argument: "arg1.1",
        otherstuff: "foo.1"
      }
    ],
    job2:[{
      command: "cmd2",
      argument: "arg2",
      otherstuff: "foo"
    }]
  },
  stage2:{
    job1:[{
      command: "cmd1",
      argument: "arg1",
      otherstuff: "foo"
    }],
    job2:[{
      command: "cmd3",
      argument: "arg3",
      otherstuff: "foo"
    }]
  }
}

# Do it
extras.values.map{|stage| 
  stage.values.map{|job|
    job.map{|item|
      {command:item[:command],argument:item[:argument]}
    }
  }
}.flatten.uniq

# It works, but is there a better way?
=> [{:command=>"cmd1", :argument=>"arg1"},
    {:command=>"cmd2", :argument=>"arg2"},
    {:command=>"cmd3", :argument=>"arg3"}]