GraphQL Cache
A custom middleware for graphql-ruby
Goals
- Provide resolver-level caching for GraphQL APIs written in ruby
- Configurable to work with or without Rails
- API Documentation
Why?
At StackShare we've been rolling out graphql-ruby for several of our new features and found ourselves in need of a caching solution. We could have simply used Rails.cache
in our resolvers, but this creates very verbose types or resolver classes. It also means that each and every resolver must define it's own expiration and key. GraphQL Cache solves that problem by integrating caching functionality into the graphql-ruby resolution process making caching transparent on most fields except for a metadata flag denoting the field as cached. More details on our motivation for creating this here.
Installation
Add this line to your application's Gemfile:
gem 'graphql-cache'
And then execute:
$ bundle
Or install it yourself as:
$ gem install graphql-cache
Setup
- Use GraphQL Cache as a plugin in your schema.
class MySchema < GraphQL::Schema
query Types::Query
use GraphQL::Cache
end
- Add the custom caching field class to your base object class. This adds the
cache
metadata key when defining fields.ruby module Types class Base < GraphQL::Schema::Object field_class GraphQL::Cache::Field end end
Configuration
GraphQL Cache can be configured in an initializer:
# config/initializers/graphql_cache.rb
GraphQL::Cache.configure do |config|
config.namespace = 'GraphQL::Cache' # Cache key prefix for keys generated by graphql-cache
config.cache = Rails.cache # The cache object to use for caching
config.logger = Rails.logger # Logger to receive cache-related log messages
config.expiry = 5400 # 90 minutes (in seconds)
config.force = false # Cache override, when true no caching takes place
end
Usage
Any object, list, or connection field can be cached by simply adding cache: true
to the field definition:
field :calculated_field, Int, cache: true
By default all keys will have an expiration of GraphQL::Cache.expiry
which defaults to 90 minutes. If you want to set a field-specific expiration time pass a hash to the cache
parameter like this:
field :calculated_field, Int, cache: { expiry: 10800 } # expires key after 180 minutes
When passing a hash in the cache
parameter the possible options are:
expiry
: expiration time for this field's key in seconds (default: 5400)force
: for cache misses on this field (default: false)prefix
: cache key prefix (appended after GraphQL::Cache.namespace)
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/stackshareio/graphql-cache. This project is intended to be a safe, welcoming space for collaboration, and contributors are expected to adhere to the Contributor Covenant code of conduct.
License
The gem is available as open source under the terms of the MIT License.
Code of Conduct
Everyone interacting in the graphql-cache project's codebases, issue trackers, chat rooms and mailing lists is expected to follow the code of conduct.