CircleCI::Parallel provides simple Ruby APIs for syncing CircleCI parallel nodes and transferring all node data to a single master node.
Add this line to your application's Gemfile:
gem 'circleci-parallel'
And then execute:
$ bundle install
Before using CircleCI::Parallel:
- Add
parallel: true
to the command that you'll use CircleCI::Parallel in yourcircle.yml
. - Set up parallelism for your project from the CircleCI web console.
CircleCI::Parallel uses SSH for syncing nodes and transferring data between nodes.
All data will be transferred to the master node (where CIRCLE_NODE_INDEX
is 0
).
# circle.yml
test:
override:
- ruby test.rb:
parallel: true
# test.rb
require 'circleci/parallel'
CircleCI::Parallel.configure do |config|
# This hook will be invoked on every node.
# The current working directory in this hook is set to the local data directory
# where node specific data should be saved in.
config.on_every_node.before_sync do
data = { 'foo' => ENV['CIRCLE_NODE_INDEX'].to_i * 10 }
json = JSON.generate(data)
File.write('data.json', json)
end
# This hook will be invoked only on the master node after downloading all data from slave nodes.
# The current working directory in this hook is set to the download data directory
# where all node data are gathered into.
# The directory structure on the master node will be the following:
#
# .
# ├── node0
# │ └── node_specific_data_you_saved_on_node0.txt
# ├── node1
# │ └── node_specific_data_you_saved_on_node1.txt
# └── node2
# └── node_specific_data_you_saved_on_node2.txt
config.on_master_node.after_download do
merged_data = {}
Dir.glob('*/data.json') do |path|
json = File.read(path)
data = JSON.parse(json)
node_name = File.dirname(path)
merged_data[node_name] = data
end
p merged_data
# {
# "node0" => { "foo" => 0 },
# "node1" => { "foo" => 10 },
# "node2" => { "foo" => 20 }
# }
end
end
# Sync all nodes in the same build and gather all node data into the master node.
# Invoking this method blocks until the sync and the data transfer is complete.
CircleCI::Parallel.sync
See API docs for more details.
The gem is available as open source under the terms of the MIT License.