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graphql-ruby under the hood
and how to write more elegant APIs
Dmitry Tsepelev, Evil Martians
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RUBYRUSSIA 2019 DmitryTsepelev
@dmitrytsepelev 2
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@dmitrytsepelev 3
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@dmitrytsepelev 4
evilmartians.com
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@dmitrytsepelev 5
evilmartians.com
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@dmitrytsepelev 6
uses graphql-ruby and wants to know how it works internally
wants to understand, how GraphQL execution engines are
implemented
wants to extend the API of graphql-ruby
wants to learn, how to dig into a popular open-source project and
start contributing
THIS TALK IS FOR PEOPLE, WHO
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@dmitrytsepelev 7
GraphQL query language
how to use GraphQL in your projects
pros and cons of GraphQL as a technology
WHAT WE ARE NOT GOING TO DISCUSS
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@dmitrytsepelev 8
DUMP 2019 Saint P Rubyconf 2019
https:!//youtu.be/xUrLslKdnr8 https:!//youtu.be/CjOwKbf8L3I?t=9615
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https:!//evl.ms/blog/graphql-on-rails-1-from-zero-to-the-first-query
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GRAPHQL FOR DUMMIES
GRAPHQL-RUBY UNDER THE HOOD
EXTENDING LIBRARY API
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every entity is a type
each type has a list of fields
some types are connected
DATA AS A GRAPH
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Request:
query {
user(id: 42) {
orders {
items {
product {
title
}
quantity
}
}
}
}
Response:
{
"data": {
"user": {
"orders": [
{
"items": [
{
"product": { "title": "iPhone 7" },
"quantity": 2
}
]
}
]
}
}
}
QUERY LANGUAGE
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@dmitrytsepelev 13
query language
execution engine
WHAT IS GRAPHQL?
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@dmitrytsepelev 14
type UserType {
id: ID!
name: String!
orders: [OrderType]!
}
SCHEMA
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@dmitrytsepelev 15
gem
serializes the data you provide
implements execution engine rules
WHAT IS GRAPHQL-RUBY?
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@dmitrytsepelev 16
$ rails generate graphql:install
route post "/graphql", to: "graphql#execute"
GraphqlController
app/graphql/ contains some base classes
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CONTROLLER AND SCHEMA
class GraphqlController < ApplicationController
def execute
result = GraphqlSchema.execute(
params[:query],
variables: params[:variables],
context: {},
operation_name: params[:operationName]
)
render json: result
end
end
class GraphqlSchema < GraphQL!::Schema
query Types!::QueryType
end
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@dmitrytsepelev 18
ROOT FIELDS
class Types!::QueryType < GraphQL!::Schema!::Object
field :user, Types!::UserType, null: true do
argument :id, ID, required: true
end
def user(id:)
User.find(id)
end
end
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@dmitrytsepelev 19
TYPE DEFINITION
class Types!::UserType < GraphQL!::Schema!::Object
field :id, ID, null: false
field :name, String, null: false
field :orders, resolver: Resolvers!::OrderResolver
end
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@dmitrytsepelev 20
GRAPHQL FOR DUMMIES
GRAPHQL-RUBY UNDER THE HOOD
EXTENDING LIBRARY API
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@dmitrytsepelev
SCHEMA DEFINITION
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GraphQL::Schema
class GraphQL!::Schema
class !<< self
def query(query_type)
@query_type = query_type
end
end
end
class GraphqlSchema < GraphQL!::Schema
query Types!::QueryType
end
application code library code
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@dmitrytsepelev 23
class GraphqlSchema < GraphQL!::Schema
lazy_resolve OrdersResolver, :orders
end
class Types!::UserType < GraphQL!::Schema!::Object
field :orders, [OrderType], null: false
def orders
OrdersResolver.new(context, object.id)
end
end
GraphQL::Schema#lazy_resolve
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class OrdersResolver
def initialize(query_ctx, user_id)
@user_id = user_id
@lazy_state = query_ctx[:lazy_find_orders] !!||= {
pending_ids: Set.new, loaded_ids: {}
}
@lazy_state[:pending_ids] !<< user_id
end
def orders
loaded_records = @lazy_state[:loaded_ids][@user_id]
return loaded_records if loaded_records
pending_ids = @lazy_state[:pending_ids].to_a
@lazy_state[:loaded_ids] = Order.where(user_id: pending_ids).group_by(&:user_id)
@lazy_state[:pending_ids].clear
@lazy_state[:loaded_ids][@user_id]
end
end
GraphQL::Schema#lazy_resolve
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@dmitrytsepelev
class GraphQL!::Schema
class !<< self
def lazy_resolve(lazy_class, value_method)
lazy_classes[lazy_class] = value_method
end
def lazy_classes
@lazy_classes !!||= {}
end
end
end
GraphQL::Schema#lazy_resolve
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@dmitrytsepelev 26
GraphQL::Schema::Object
class GraphQL!::Schema!::Object
class !<< self
def field(*args, !**kwargs, &block)
own_fields[field_defn.name] =
field_class.from_options(
*args, !**kwargs, &block
)
end
def own_fields
@own_fields !!||= {}
end
end
end
class Types!::UserType
field :id, ID, null: false
end
application code library code
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@dmitrytsepelev 27
GraphQL::Schema::Object
class GraphQL!::Schema!::Object
class !<< self
def field(*args, !**kwargs, &block)
own_fields[field_defn.name] =
GraphQL!::Schema!::Field.from_options(
*args, !**kwargs, &block
)
end
def own_fields
@own_fields !!||= {}
end
end
end
class Types!::UserType
field :id, ID, null: false
end
application code library code
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@dmitrytsepelev
GraphQL::Schema::Field
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class GraphQL!::Schema!::Field
def self.from_options(name = nil, …, !**kwargs, &block)
kwargs[:name] = name if name
new(!**kwargs, &block)
end
attr_accessor :name
def initialize(…, &definition_block)
@name = name
@type = type
@null = null
…
end
end
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&definition_block
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class Types!::QueryType < GraphQL!::Schema!::Object
field :user, Types!::UserType, null: true do
argument :id, ID, required: true
end
end
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@dmitrytsepelev 30
GraphQL::Schema::Field
class GraphQL!::Schema!::Field
def initialize(!!..., &definition_block)
instance_eval(&definition_block) if definition_block
end
def argument(*args, !**kwargs, &block)
arg_defn = GraphQL!::Schema!::Argument.new(*args, !**kwargs, &block)
own_arguments[arg_defn.name] = arg_defn
end
def own_arguments
@own_arguments !!||= {}
end
end
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@dmitrytsepelev 31
#
FIELD DATA STRUCTURE
class Types!::UserType < GraphQL!::Schema!::Object
field :id, ID, null: false
field :name, String, null: false
field :orders,
resolver: Resolvers!::OrderResolver
end
Types!::UserType.fields
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@dmitrytsepelev 32
# #,
"perPage"!=> #
}
>
class Types!::UserType < GraphQL!::Schema!::Object
field :id, ID, null: false
field :name, String, null: false
field :orders,
resolver: Resolvers!::OrderResolver
end
Types!::UserType.fields
FIELD DATA STRUCTURE
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@dmitrytsepelev
RESOLVING QUERIES
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@dmitrytsepelev
GraphQL::Schema#execute
class GraphQL!::Schema
def self.execute(query_str = nil, !**kwargs)
kwargs[:query] = query_str if query_str
all_results = GraphQL!::Execution!::Multiplex.run_all(self, [kwargs])
all_results[0]
end
end
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@dmitrytsepelev
class GraphQL!::Execution!::Multiplex
class !<< self
def run_all(schema, query_options, *args)
queries = query_options.map do |opts|
GraphQL!::Query.new(schema, nil, opts)
end
run_queries(schema, queries, *args)
end
end
end
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Schema.execute
⇨ Multiplex.run_all
GraphQL::Execution::Multiplex.run_all
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@dmitrytsepelev
GraphQL::Query#prepare_ast
GraphQL!::Language!::Parser.parse !!<<-QUERY
query {
user {
name
}
}
QUERY
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query
user
name
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@dmitrytsepelev
@operation_type= @name= @name=
GraphQL::Query#prepare_ast
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query user name
Document
OperationDefinition Field Field
@selections
@selections
@definitions
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@dmitrytsepelev
class GraphQL!::Execution!::Multiplex
class !<< self
def run_all(schema, query_options, *args)
queries = query_options.map do |opts|
GraphQL!::Query.new(schema, nil, opts)
end
run_queries(schema, queries, *args)
end
end
end
GraphQL::Execution::Multiplex.run_all
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Schema.execute
⇨ Multiplex.run_all
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@dmitrytsepelev
GraphQL::Execution::Multiplex#run_as_multiplex
class GraphQL!::Execution!::Multiplex
def run_as_multiplex(multiplex)
strategy = multiplex.schema.query_execution_strategy
results = multiplex.queries.map do |query|
strategy.begin_query(query, multiplex)
end
results.each_with_index.map do |data_result, idx|
multiplex.queries[idx].result
end
end
end
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Schema.execute
Multiplex.run_all
…
⇨ Multiplex#run_as_multiplex
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@dmitrytsepelev
GraphQL::Execution::Execute
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class GraphQL!::Execution!::Execute
def self.begin_query(query, _multiplex)
ExecutionFunctions.resolve_root_selection(query)
end
end
Schema.execute
Multiplex.run_all
…
Multiplex#run_as_multiplex
⇨ Execute.begin_query
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@dmitrytsepelev
ExecutionFunctions.resolve_root_selection
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module ExecutionFunctions
def resolve_root_selection(query)
operation = query.selected_operation
root_type = query.root_type_for_operation(
operation.operation_type
)
resolve_selection(
query.root_value,
root_type,
query.context
)
end
end
Schema.execute
Multiplex.run_all
…
Multiplex#run_as_multiplex
Execute.begin_query
⇨ ExecutionFunctions.resolve_root_selection
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@dmitrytsepelev
ExecutionFunctions.resolve_selection
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module ExecutionFunctions
def resolve_selection(object, current_type, current_ctx)
current_ctx.value = {}
selections_on_type =
current_ctx.irep_node
.typed_children[current_type]
selections_on_type.each do |name|
field_ctx = current_ctx.spawn_child(!!...)
resolve_field(object, field_ctx)
current_ctx.value[name] = field_ctx
end
current_ctx.value
end
end
Schema.execute
Multiplex.run_all
…
Multiplex#run_as_multiplex
Execute.begin_query
ExecutionFunctions.resolve_root_selection
⇨ ExecutionFunctions.resolve_selection
resolve_selection
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@dmitrytsepelev
module ExecutionFunctions
def resolve_field(object, field_ctx)
raw_value = field_ctx.schema
.middleware
.invoke(object, field_ctx)
field_ctx.value = resolve_value(
raw_value, field_ctx.type, field_ctx
)
end
end
ExecutionFunctions.resolve_field
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Schema.execute
Multiplex.run_all
…
Multiplex#run_as_multiplex
Execute.begin_query
ExecutionFunctions.resolve_root_selection
ExecutionFunctions.resolve_selection
⇨ ExecutionFunctions.resolve_field
resolve_field
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@dmitrytsepelev 44
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FieldResolveStep
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module FieldResolveStep
def self.call(
_parent_type,
parent_object,
field_definition,
field_args,
context
)
field_definition.resolve(
parent_object, field_args, context
)
end
end
Schema.execute
Multiplex.run_all
…
Multiplex#run_as_multiplex
Execute.begin_query
ExecutionFunctions.resolve_root_selection
ExecutionFunctions.resolve_selection
ExecutionFunctions.resolve_field
…
⇨ FieldResolverStep.call
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@dmitrytsepelev
GraphQL::Schema::Field#resolve
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class GraphQL!::Schema!::Field
def resolve(object, args, ctx)
with_extensions(object, args, ctx) do |e_obj, e_args|
field_receiver = if @resolver_class
@resolver_class.new(object: e_obj, context: ctx)
else
e_obj
end
if field_receiver.respond_to?(@resolver_method)
field_receiver.public_send(@resolver_method, !**e_args)
else
resolve_field_method(field_receiver, e_args, ctx)
end
end
end
end
Schema.execute
Multiplex.run_all
…
Multiplex#run_as_multiplex
Execute.begin_query
ExecutionFunctions.resolve_root_selection
ExecutionFunctions.resolve_selection
ExecutionFunctions.resolve_field
…
FieldResolverStep.call
⇨ Field#resolve
resolve
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@dmitrytsepelev
GraphQL::Schema::Field#resolve
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class GraphQL!::Schema!::Field
def resolve(object, args, ctx)
with_extensions(object, args, ctx) do |e_obj, e_args|
field_receiver = if @resolver_class
@resolver_class.new(object: e_obj, context: ctx)
else
e_obj
end
if field_receiver.respond_to?(@resolver_method)
field_receiver.public_send(@resolver_method, !**e_args)
else
resolve_field_method(field_receiver, e_args, ctx)
end
end
end
end
resolve
#
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@dmitrytsepelev
GraphQL::Schema::Field#resolve
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class GraphQL!::Schema!::Field
def resolve(object, args, ctx)
with_extensions(object, args, ctx) do |e_obj, e_args|
field_receiver = OrderResolver.new(
object: e_obj, context: ctx
)
if field_receiver.respond_to?(@resolver_method)
field_receiver.public_send(@resolver_method, !**e_args)
else
resolve_field_method(field_receiver, e_args, ctx)
end
end
end
end
resolve
#
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@dmitrytsepelev
GraphQL::Schema::Field#resolve
49
class GraphQL!::Schema!::Field
def resolve(object, args, ctx)
with_extensions(object, args, ctx) do |e_obj, e_args|
field_receiver = OrderResolver.new(
object: e_obj, context: ctx
)
if field_receiver.respond_to?(@resolver_method)
field_receiver.public_send(@resolver_method, !**e_args)
else
resolve_field_method(field_receiver, e_args, ctx)
end
end
end
end
resolve
#
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@dmitrytsepelev
GraphQL::Schema::Field#resolve
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class GraphQL!::Schema!::Field
def resolve(object, args, ctx)
with_extensions(object, args, ctx) do |e_obj, e_args|
field_receiver = OrderResolver.new(
object: e_obj, context: ctx
)
field_receiver.public_send(@resolver_method, !**e_args)
end
end
end
resolve
#
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@dmitrytsepelev
GraphQL::Schema::Field#resolve
51
class GraphQL!::Schema!::Field
def resolve(object, args, ctx)
with_extensions(object, args, ctx) do |e_obj, e_args|
field_receiver = OrderResolver.new(
object: e_obj, context: ctx
)
field_receiver.public_send(:resolve, !**e_args)
end
end
end
resolve
#
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@dmitrytsepelev
GraphQL::Schema::Field#resolve
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class GraphQL!::Schema!::Field
def resolve(object, args, ctx)
with_extensions(object, args, ctx) do |e_obj, e_args|
field_receiver = if @resolver_class
@resolver_class.new(object: e_obj, context: ctx)
else
e_obj
end
if field_receiver.respond_to?(@resolver_method)
field_receiver.public_send(@resolver_method, !**e_args)
else
resolve_field_method(field_receiver, e_args, ctx)
end
end
end
end
resolve
#
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@dmitrytsepelev
GraphQL::Schema::Field#resolve
53
class GraphQL!::Schema!::Field
def resolve(object, args, ctx)
with_extensions(object, args, ctx) do |e_obj, e_args|
field_receiver = e_obj
if field_receiver.respond_to?(@resolver_method)
field_receiver.public_send(@resolver_method, !**e_args)
else
resolve_field_method(field_receiver, e_args, ctx)
end
end
end
end
resolve
#
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@dmitrytsepelev
GraphQL::Schema::Field#resolve
54
class GraphQL!::Schema!::Field
def resolve(object, args, ctx)
with_extensions(object, args, ctx) do |e_obj, e_args|
field_receiver = e_obj
if field_receiver.respond_to?(@resolver_method)
field_receiver.public_send(@resolver_method, !**e_args)
else
resolve_field_method(field_receiver, e_args, ctx)
end
end
end
end
resolve
#
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@dmitrytsepelev
GraphQL::Schema::Field#resolve
55
class GraphQL!::Schema!::Field
def resolve(object, args, ctx)
with_extensions(object, args, ctx) do |e_obj, e_args|
field_receiver = e_obj
field_receiver.public_send(:name, !**e_args)
end
end
end
resolve
#
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@dmitrytsepelev
module ExecutionFunctions
def resolve_field(object, field_ctx)
raw_value = field_ctx.schema
.middleware
.invoke(object, field_ctx)
field_ctx.value = resolve_value(
raw_value, field_ctx.type, field_ctx
)
end
end
ExecutionFunctions.resolve_field
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Schema.execute
Multiplex.run_all
…
Multiplex#run_as_multiplex
Execute.begin_query
ExecutionFunctions.resolve_root_selection
ExecutionFunctions.resolve_selection
⇨ ExecutionFunctions.resolve_field
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@dmitrytsepelev
ExecutionFunctions.resolve_value
57
module ExecutionFunctions
def resolve_value(value, field_type, field_ctx)
field_defn = field_ctx.field
case field_type.kind
when GraphQL!::TypeKinds!::SCALAR
field_type.coerce_result(value, field_ctx)
when GraphQL!::TypeKinds!::OBJECT
resolve_selection(value, field_type, field_ctx)
end
end
end
Schema.execute
Multiplex.run_all
…
Multiplex#run_as_multiplex
Execute.begin_query
ExecutionFunctions.resolve_root_selection
ExecutionFunctions.resolve_selection
ExecutionFunctions.resolve_field
…
⇨ ExecutionFunctions.resolve_value
resolve_value
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@dmitrytsepelev
class GraphQL!::Execution!::Multiplex
def run_as_multiplex(multiplex)
strategy = multiplex.schema.query_execution_strategy
results = multiplex.queries.map do |query|
strategy.begin_query(query, multiplex)
end
results.each_with_index.map do |data_result, idx|
multiplex.queries[idx].result
end
end
end
GraphQL::Execution::Multiplex#run_as_multiplex
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Schema.execute
Multiplex.run_all
…
⇨ Multiplex#run_as_multiplex
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@dmitrytsepelev
IS IT SLOW?
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https:!//gist.github.com/DmitryTsepelev/36e290cf64b4ec0b18294d0a57fb26ff
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@dmitrytsepelev 60
GRAPHQL PARSER BENCHMARK
fields – count of fields in each selection set
nested levels – count of nested levels
query {
field1 {
field1
field2
}
field2 {
field1
field2
}
}
fields = 2, nested levels = 1
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@dmitrytsepelev 61
user system total real
1 fields, 0 nested levels: 0.000153 0.000002 0.000155 ( 0.000152)
1 fields, 2 nested levels: 0.000188 0.000001 0.000189 ( 0.000187)
1 fields, 4 nested levels: 0.000252 0.000001 0.000253 ( 0.000240)
2 fields, 0 nested levels: 0.000134 0.000013 0.000147 ( 0.000132)
2 fields, 2 nested levels: 0.000420 0.000006 0.000426 ( 0.000411)
2 fields, 4 nested levels: 0.001695 0.000001 0.001696 ( 0.001694)
4 fields, 0 nested levels: 0.000154 0.000001 0.000155 ( 0.000153)
4 fields, 2 nested levels: 0.001744 0.000001 0.001745 ( 0.001744)
4 fields, 4 nested levels: 0.032188 0.000269 0.032457 ( 0.032581)
8 fields, 0 nested levels: 0.000316 0.000034 0.000350 ( 0.000352)
8 fields, 2 nested levels: 0.013464 0.000218 0.013682 ( 0.013917)
8 fields, 4 nested levels: 0.910159 0.008081 0.918240 ( 0.919507)
GRAPHQL PARSER BENCHMARK
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30.50 kB (285 objects)
/users/1?include=orders&fields[users]=id,name&fields[orders]=id,placed_at
{
"data" !=> {
"id"!=>"1", "type"!=>"users", "links"!=>{"self"!=>"users/1"},
"attributes"!=>{"id"!=>"1", "name"!=>"John Doe"}
},
"included"!=> [
{
"id"!=>"1", "type"!=>"orders", "links"!=>{"self"!=>"orders/1"},
"attributes"!=>{"id"!=>1, "placed_at"!=>"2019-09-21T12:56:31+03:00"}
},
{
"id"!=>"2", "type"!=>"orders", "links"!=>{"self"!=>"orders/2"},
"attributes"!=>{"id"!=>2, "placed_at"!=>"2019-09-21T12:56:31+03:00"}
}
]
}
MEMORY PROFILER (JSON API)
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113.19 kB (1059 objects)
query GetUser($id: ID!) {
user(id: $id) {
id
name
orders {
id
placedAt
}
}
}
{
"data" !=> {
"user" !=> {
"id"!=>"1",
"name"!=>"John Doe",
"orders"!=>[
{
"id"!=>"1",
"placedAt"!=>"2019-09-21T13:00:02+03:00"
},
{
"id"!=>"2",
"placedAt"!=>"2019-09-21T13:00:02+03:00"
}
]
}
}
}
MEMORY PROFILER (GRAPHQL)
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GRAPHQL FOR DUMMIES
GRAPHQL-RUBY UNDER THE HOOD
EXTENDING LIBRARY API
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BLOCK-BASED API
Types!::Post = GraphQL!::ObjectType.define do
field :comments, types[Types!::Comments] do
argument :orderBy, Types!::CommentOrder
resolve !->(obj, args, ctx) {
obj.comments.order(args[:orderBy])
}
end
end
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@dmitrytsepelev 66
looks more like JavaScript than Ruby
problems with constant loading (especially in Rails)
hard to patch
https:!//rmosolgo.github.io/blog/2018/03/25/why-a-new-schema-definition-api/
BLOCK-BASED API
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@dmitrytsepelev 67
graphql-ruby supports both APIs
some classes look more complex than they could
some old plugins do not work
BLOCK-BASED API
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GRAPHQL-BATCH
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class GraphqlSchema < GraphQL!::Schema
query QueryType
use GraphQL!::Batch
end
class QueryType < GraphQL!::Schema!::Object
field :product_title, String, null: true do
argument :id, ID, required: true
end
def product_title(id:)
RecordLoader.for(Product).load(id).then(&:title)
end
end
SETUP AND USAGE
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class RecordLoader < GraphQL!::Batch!::Loader
def initialize(model)
@model = model
end
def perform(ids)
@model.where(id: ids).each do |record|
fulfill(record.id, record)
end
ids.each do |id|
fulfill(id, nil) unless fulfilled?(id)
end
end
end
LOADING DATA
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class GraphQL!::Schema
class !<< self
def use(plugin, options = {})
plugins !<< [plugin, options]
end
def plugins
@plugins !!||= []
end
def to_graphql
plugins.each { |plugin| plugin.use(self) }
end
end
end
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HOW SCHEMA LOADS PLUGINS
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PATCHING SCHEMA WITH #use
module GraphQL"::Batch
def self.use(schema_defn, executor_class: GraphQL!::Batch!::Executor)
instrumentation = GraphQL!::Batch!::SetupMultiplex.new(
schema, executor_class: executor_class
)
schema_defn.instrument(:multiplex, instrumentation)
schema_defn.lazy_resolve(!::Promise, :sync)
end
end
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REDEFINING FIELD RESOLVER
class GraphQL!::Batch!::SetupMultiplex
def instrument(type, field)
old_resolve_proc = field.resolve_proc
field.redefine do
resolve !->(obj, args, ctx) {
!::Promise.sync(old_resolve_proc.call(obj, args, ctx))
}
end
end
end
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@dmitrytsepelev
FIELD EXTENSIONS
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HOW TO EXTEND A FIELD
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class Types!::QueryType < GraphQL!::Schema!::Object
field :users,
[Types!::UserType],
null: false,
extensions: [SearchableExtension]
def users(query:)
User.search(query)
end
end
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ADDING ARGUMENT TO A FIELD USING EXTENSION
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class SearchableExtension < GraphQL!::Schema!::FieldExtension
def apply
field.argument(:query, String, required: false)
end
end
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HOW EXTENSIONS WORK
77
class GraphQL!::Schema!::Field
def resolve(object, args, ctx)
with_extensions(object, args, ctx) do |e_obj, e_args|
# resolve logic
end
end
def with_extensions(obj, args, ctx)
extensions.each do |extension|
obj, args = extension.resolve(
object: obj, arguments: args, context: ctx
)
end
yield(obj, args)
end
end
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@dmitrytsepelev
PLUGIN IN 5 MINUTES ⏰
78
https:!//gist.github.com/DmitryTsepelev/065bb6bc796898f5745c4209d1b4bb21
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WHAT WE ARE BUILDING
class QueryType < BaseObject
field :cached_val, String, null: false
def cached_val
"I'm cached at "#{Time.now}"
end
end
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ADDING EXTENSION TO THE FIELD
class QueryType < BaseObject
field :cached_val, String, null: false, extensions: [CacheExtension]
def cached_val
"I'm cached at "#{Time.now}"
end
end
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HOW TO IMPLEMENT THE EXTENSION
class CacheExtension < GraphQL!::Schema!::FieldExtension
def resolve(object:, arguments:, !**rest)
key = cache_key(object, arguments)
store[key] !!||= yield(object, arguments)
end
private
def store
Thread.current[:field_cache] !!||= {}
end
def cache_key(object, arguments)
""#{object.class.name}-"#{@field}-"#{arguments.hash}"
end
end
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I WANT TO USE KWARG!
class QueryType < BaseObject
field :cached_val, String, null: false, cached: true
def cached_val
"I'm cached at "#{Time.now}"
end
end
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PATCHING BASE CLASS
class BaseObject < GraphQL!::Schema!::Object
field_class.prepend(Module.new do
def initialize(*args, !**kwargs, &block)
if kwargs.delete(:cached)
kwargs[:extensions] !!||= [] !<< CacheExtension
end
super
end
end)
end
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@dmitrytsepelev 84
graphql-ruby is a complex library with a complex architecture
this architecture allows to extend the functionality of the library
benefits coming with GraphQL do not require to sacrifice the
performance
TO SUM UP
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evl.ms/blog
@dmitrytsepelev
DmitryTsepelev
@evilmartians
evl.ms/telegram
THANK YOU!
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