graphql connections

Additional implementations of cursor-based paginations for GraphQL Ruby gem.

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Ruby

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GraphQL::Connections

Additional implementations of cursor-based paginations for GraphQL Ruby.

Sponsored by Evil Martians

Installation

Add this line to your application’s Gemfile:

gem "graphql-connections"

Usage

ActiveRecord

Implements Relay specification for serving stable connections based on column values.
If objects are created or destroyed during pagination, the list of items won’t be disrupted.

You can use a stable connection wrapper on a specific field:

field :messages, Types::Message.connection_type, null: false

def messages
  GraphQL::Connections::Stable.new(Message.all)
end

Records are sorted by model’s primary key by default. You can change this behaviour by providing primary_key param:

GraphQL::Connections::Stable.new(Message.all, primary_key: :created_at)

In case when you want records to be sorted by more than one field (i.e., keyset pagination), you can use keys param:

GraphQL::Connections::Stable.new(Message.all, keys: %w[name id])

When you pass only one key, a primary key will be added as a second one:

GraphQL::Connections::Stable.new(Message.all, keys: [:name])

NOTE: Currently we support maximum two keys in the keyset.

Also, you can pass the :desc option to reverse the relation:

GraphQL::Connections::Stable.new(Message.all, keys: %w[name id], desc: true)
GraphQL::Connections::Stable.new(Message.all, primary_key: :created_at, desc: true)

Also, you can disable opaque cursors by setting opaque_cursor param:

GraphQL::Connections::Stable.new(Message.all, opaque_cursor: false)

Or you can apply a stable connection to all Active Record relations returning by any field:

class ApplicationSchema < GraphQL::Schema
  connections.add(ActiveRecord::Relation, GraphQL::Connections::Stable)
end

NOTE: Don’t use stable connections for relations whose ordering is too complicated for cursor generation.

Elasticsearch via Chewy

Register connection for all Chewy requests:

class ApplicationSchema < GraphQL::Schema
  connections.add(Chewy::Search::Request, GraphQL::Connections::ChewyConnection)
end

And define field like below:

field :messages, Types::Message.connection_type, null: false

def messages
  CitiesIndex.query(match: {name: "Moscow"})
end

NOTE: Using first and lastarguments simultaneously is not supported yet.

Development

After checking out the repo, run bin/setup to install dependencies. Then, run rake spec to run the tests. You can also run bin/console for an interactive prompt that will allow you to experiment.

To install this gem onto your local machine, run bundle exec rake install. To release a new version, update the version number in version.rb, and then run bundle exec rake release, which will create a git tag for the version, push git commits and tags, and push the .gem file to rubygems.org.

Contributing

Bug reports and pull requests are welcome on GitHub at https://github.com/bibendi/graphql-connections.

License

The gem is available as open source under the terms of the MIT License.