GraphQLDocs

Easily generate beautiful documentation from your GraphQL schema.

Installation

Add this line to your application's Gemfile:

gem 'graphql-docs'

And then execute:

$ bundle

Or install it yourself as:

$ gem install graphql-docs

Usage

# pass in a filename
GraphQLDocs.build(filename: filename)

# or pass in a string
GraphQLDocs.build(schema: contents)

# or a schema class
schema = GraphQL::Schema.define do
  query query_type
end
GraphQLDocs.build(schema: schema)

Breakdown

There are several phases going on the single GraphQLDocs.build call:

The GraphQL IDL file is read (if you passed filename) through GraphQL::Client (or simply read if you passed a string through schema).
GraphQL::Parser manipulates the IDL into a slightly saner format.
GraphQL::Generator takes that saner format and begins the process of applying items to the HTML templates.
GraphQL::Renderer technically runs as part of the generation phase. It passes the contents of each page and converts it into HTML.

If you wanted to, you could break these calls up individually. For example:

options = {}
options[:filename] = "#{File.dirname(__FILE__)}/../data/graphql/schema.idl"
options[:renderer] = MySuperCoolRenderer

options = GraphQLDocs::Configuration::GRAPHQLDOCS_DEFAULTS.merge(options)

response = File.read(options[:filename])

parser = GraphQLDocs::Parser.new(response, options)
parsed_schema = parser.parse

generator = GraphQLDocs::Generator.new(parsed_schema, options)

generator.generate

Generating output

By default, the HTML generation process uses ERB to layout the content. There are a bunch of default options provided for you, but feel free to override any of these. The Configuration section below has more information on what you can change.

It also uses html-pipeline to perform the rendering by default. You can override this by providing a custom rendering class.You must implement two methods:

initialize - Takes two arguments, the parsed schema and the configuration options.
render Takes the contents of a template page. It also takes two optional kwargs, the GraphQL type and its name. For example:

class CustomRenderer
  def initialize(parsed_schema, options)
    @parsed_schema = parsed_schema
    @options = options
  end

  def render(contents, type: nil, name: nil)
    contents.sub(/Repository/i, '<strong>Meow Woof!</strong>')

    opts[:content] = contents
    @graphql_default_layout.result(OpenStruct.new(opts).instance_eval { binding })
  end
end

options[:filename] = 'location/to/sw-api.graphql'
options[:renderer] = CustomRenderer

GraphQLDocs.build(options)

If your render method returns nil, the Generator will not attempt to write any HTML file.

Templates

The layouts for the individual GraphQL pages are ERB templates, but you can also use ERB templates for your static landing pages.

If you want to add additional variables for your landing pages, you can add define a variables hash within the landing_pages option.

Helper methods

In your ERB layouts, there are several helper methods you can use. The helper methods are:

slugify(str) - This slugifies the given string.
include(filename, opts) - This embeds a template from your includes folder, passing along the local options provided.
markdownify(string) - This converts a string into HTML via CommonMarker.
graphql_operation_types, graphql_mutation_types, graphql_object_types, graphql_interface_types, graphql_enum_types, graphql_union_types, graphql_input_object_types, graphql_scalar_types - Collections of the various GraphQL types.

To call these methods within templates, you must use the dot notation, such as <%= slugify.(text) %>.

Configuration

The following options are available:

Option	Description	Default
`filename`	The location of your schema's IDL file.	`nil`
`schema`	A string representing a schema IDL file.	`nil`
`output_dir`	The location of the output HTML.	`./output/`
`use_default_styles`	Indicates if you want to use the default styles.	`true`
`base_url`	Indicates the base URL to prepend for assets and links.	`""`
`delete_output`	Deletes `output_dir` before generating content.	`false`
`pipeline_config`	Defines two sub-keys, `pipeline` and `context`, which are used by `html-pipeline` when rendering your output.	`pipeline` has `ExtendedMarkdownFilter`, `EmojiFilter`, and `TableOfContentsFilter`. `context` has `gfm: false` and `asset_root` set to GitHub's CDN.
`renderer`	The rendering class to use.	`GraphQLDocs::Renderer`
`templates`	The templates to use when generating HTML. You may override any of the following keys: `default`, `includes`, `operations`, `objects`, `mutations`, `interfaces`, `enums`, `unions`, `input_objects`, `scalars`.	The defaults are found in lib/graphql-docs/layouts/.
`landing_pages`	The landing page to use when generating HTML for each type. You may override any of the following keys: `index`, `query`, `object`, `mutation`, `interface`, `enum`, `union`, `input_object`, `scalar`.	The defaults are found in lib/graphql-docs/layouts/.
`classes`	Additional class names you can provide to certain elements.	The full list is available in lib/graphql-docs/configuration.rb.
`notices`	A proc used to add notices to schema members. See Customizing Notices section below.	`nil`

Customizing Notices

A notice is a block of CommonMark text that optionally has a title which is displayed above a schema member's description. The look of a notice block can be controlled by specifying a custom class for it and then styled via CSS.

The notices option allows you to customize the notices that appear for a specific schema member using a proc.

The proc will be called for each schema member and needs to return an array of notices or an empty array if there are none.

A notice has the following options:

Option	Description
`body`	CommonMark body of the notice
`title`	Optional title of the notice
`class`	Optional CSS class for the wrapper `<div>` of the notice
`title_class`	Optional CSS class for the `<span>` of the notice's title

Example of a notices proc that adds a notice to the TeamDiscussion type:

options[:notices] = ->(schema_member_path) {
  notices = []

  if schema_member_path == "TeamDiscussion"
    notices << {
      class: "preview-notice",
      body: "Available via the [Team Discussion](/previews/team-discussion) preview.",
    }
  end

  notices
}

The format of schema_member_path is a dot delimited path to the schema member. For example:

"Author", # an object
"ExtraInfo" # an interface,
"Author.socialSecurityNumber" # a field
"Book.author.includeMiddleInitial" # an argument
"Likeable" # a union,
"Cover" # an enum
"Cover.DIGITAL" # an enum value
"BookOrder" # an input object
"Mutation.addLike" # a mutation

Development

After checking out the repo, run script/bootstrap to install dependencies. Then, run rake test to run the tests. You can also run bundle exec rake console for an interactive prompt that will allow you to experiment.

Sample site

Clone this repository and run:

bundle exec rake sample

to see some sample output.

cmatheson/graphql-docs