First simple API version with autogenerated GraphQL types

app/graph/exposable_field.rb

@@ -0,0 +1,26 @@
+class ExposableField
+  attr_reader :name, :graphql_type
+
+  def initialize(column, options = {})
+    @name = column.name
+    @graphql_type = ExposableField.convert_type(column.type)
+  end
+
+  private
+
+  # Return a GraphQL type for 'database_type'
+  def self.convert_type(database_type)
+    case database_type
+    when :integer
+      GraphQL::INT_TYPE
+    when :boolean
+      GraphQL::BOOLEAN_TYPE
+    when :float
+      GraphQL::FLOAT_TYPE
+    when :double
+      GraphQL::FLOAT_TYPE
+    else
+      GraphQL::STRING_TYPE
+    end
+  end
+end

app/graph/exposable_model.rb

@@ -0,0 +1,31 @@
+class ExposableModel
+  attr_reader :exposed_fields, :name, :description
+
+  def initialize(model_class, options = {})
+    @model_class = model_class
+    @filter_list = options[:filter_list] || []
+    @name = model_class.name
+    @description = model_class.model_name.human
+    @filter_strategy = options[:filter_strategy]
+    set_exposed_fields
+  end
+
+  private
+
+  # determine which model fields are exposed to the API
+  def set_exposed_fields
+    case @filter_strategy
+    when :whitelist
+      @exposed_fields = @model_class.columns.select do |column|
+        @filter_list.include? column.name
+      end
+    when :blacklist
+      @exposed_fields = @model_class.columns.select do |column|
+        !(@filter_list.include? column.name)
+      end
+    else
+      @exposed_fields = []
+    end
+  end
+
+end

app/graph/query_root.rb

@@ -3,7 +3,7 @@ QueryRoot = GraphQL::ObjectType.define do
   description "The query root for this schema"
 
   field :proposal do
-    type ProposalType
+    type TYPE_BUILDER.types[Proposal]
     description "Find a Proposal by id"
     argument :id, !types.ID
     resolve -> (object, arguments, context) {
@@ -11,7 +11,8 @@ QueryRoot = GraphQL::ObjectType.define do
     }
   end
 
-  connection :proposals, ProposalType.connection_type do
+  field :proposals do
+    type types[TYPE_BUILDER.types[Proposal]]
     description "Find all Proposals"
     resolve -> (object, arguments, context) {
       Proposal.all
@@ -19,7 +20,7 @@ QueryRoot = GraphQL::ObjectType.define do
   end
 
   field :debate do
-    type DebateType
+    type TYPE_BUILDER.types[Debate]
     description "Find a Debate by id"
     argument :id, !types.ID
     resolve -> (object, arguments, context) {
@@ -27,7 +28,8 @@ QueryRoot = GraphQL::ObjectType.define do
     }
   end
 
-  connection :debates, DebateType.connection_type do
+  field :debates do
+    type types[TYPE_BUILDER.types[Debate]]
     description "Find all Debates"
     resolve -> (object, arguments, context) {
       Debate.all
@@ -35,7 +37,7 @@ QueryRoot = GraphQL::ObjectType.define do
   end
 
   field :comment do
-    type CommentType
+    type TYPE_BUILDER.types[Comment]
     description "Find a Comment by id"
     argument :id, !types.ID
     resolve -> (object, arguments, context) {
@@ -43,7 +45,8 @@ QueryRoot = GraphQL::ObjectType.define do
     }
   end
 
-  connection :comments, CommentType.connection_type do
+  field :comments do
+    type types[TYPE_BUILDER.types[Comment]]
     description "Find all Comments"
     resolve -> (object, arguments, context) {
       Comment.all
@@ -51,7 +54,7 @@ QueryRoot = GraphQL::ObjectType.define do
   end
 
   field :user do
-    type UserType
+    type TYPE_BUILDER.types[User]
     description "Find a User by id"
     argument :id, !types.ID
     resolve -> (object, arguments, context) {

app/graph/type_builder.rb

@@ -0,0 +1,57 @@
+class TypeBuilder
+  attr_reader :filter_strategy, :graphql_models
+
+  def initialize(graphql_models, options = {})
+    @graphql_models = graphql_models
+    @graphql_types = {}
+
+    # determine filter strategy for this field
+    if (options[:filter_strategy] == :blacklist)
+      @filter_strategy = :blacklist
+    else
+      @filter_strategy = :whitelist
+    end
+
+    create_all_types
+  end
+
+  def types
+    @graphql_types
+  end
+
+private
+
+  def create_all_types
+    @graphql_models.keys.each do |model_class|
+      @graphql_types[model_class] = create_type(model_class)
+    end
+  end
+
+  def create_type(model_class)
+    type_builder = self
+
+    graphql_type = GraphQL::ObjectType.define do
+      em = ExposableModel.new(model_class, filter_strategy: type_builder.filter_strategy, filter_list: type_builder.graphql_models[model_class])
+
+      name(em.name)
+      description(em.description)
+
+      em.exposed_fields.each do |column|
+        ef = ExposableField.new(column)
+        field(ef.name, ef.graphql_type)
+      end
+    end
+
+    return graphql_type
+  end
+end
+
+graphql_models = {}
+
+graphql_models.store(User, ['id', 'username'])
+graphql_models.store(Proposal, ['id', 'title', 'description', 'author_id', 'created_at'])
+graphql_models.store(Debate, ['id', 'title', 'description', 'author_id', 'created_at'])
+graphql_models.store(Comment, ['id', 'commentable_id', 'commentable_type', 'body'])
+graphql_models.store(Geozone, ['id', 'name', 'html_map_coordinates'])
+
+TYPE_BUILDER = TypeBuilder.new(graphql_models, filter_strategy: :whitelist)

config/application.rb

@@ -46,7 +46,7 @@ module Consul
     config.paths['app/views'].unshift(Rails.root.join('app', 'views', 'custom'))
 
     # Add GraphQL directories to the autoload path
-    config.autoload_paths << Rails.root.join('app', 'graph', 'types')
+    config.autoload_paths << Rails.root.join('app', 'graph')
   end
 end