GraphQL for Python.

This library is a port of graphql-js to Python and currently is up-to-date with release 0.6.0.

See more complete documentation at http://graphql.org/ and http://graphql.org/docs/api-reference-graphql/.

For questions, ask Stack Overflow.

An overview of the GraphQL language is available in the README for the Specification for GraphQL. The overview describes a simple set of GraphQL examples that exist as tests in this repository. A good way to get started is to walk through that README and the corresponding tests in parallel.

Install from pip:

pip install graphql-core

GraphQL.js provides two important capabilities: building a type schema, and serving queries against that type schema.

First, build a GraphQL type schema which maps to your code base.

from graphql import ( graphql, GraphQLSchema, GraphQLObjectType, GraphQLField, GraphQLString ) schema = GraphQLSchema( query= GraphQLObjectType( name='RootQueryType', fields={ 'hello': GraphQLField( type= GraphQLString, resolver=lambda *_: 'world' ) } ) )

This defines a simple schema with one type and one field, that resolves to a fixed value. The resolve function can return a value, a promise, or an array of promises. A more complex example is included in the top level tests directory.

Then, serve the result of a query against that type schema.

query = '{ hello }' result = graphql(schema, query) # Prints # {'hello': 'world'} (as OrderedDict) print result.data

This runs a query fetching the one field defined. The graphql function will first ensure the query is syntactically and semantically valid before executing it, reporting errors otherwise.

query = '{ boyhowdy }' result = graphql(schema, query) # Prints # [GraphQLError('Cannot query field "boyhowdy" on type "RootQueryType".',)] print result.errors

The graphql query is executed, by default, synchronously (using SyncExecutor). However the following executors are available if we want to resolve our fields in parallel:

• graphql.execution.executors.asyncio.AsyncioExecutor: This executor executes the resolvers in the Python asyncio event loop.
• graphql.execution.executors.gevent.GeventExecutor: This executor executes the resolvers in the Gevent event loop.
• graphql.execution.executors.process.ProcessExecutor: This executor executes each resolver as a process.
• graphql.execution.executors.thread.ThreadExecutor: This executor executes each resolver in a Thread.
• graphql.execution.executors.sync.SyncExecutor: This executor executes each resolver synchronusly (default).

You can specify the executor to use via the executor keyword argument in the grapqhl.execution.execute function.

from graphql.execution.execute import execute execute(schema, ast, executor=SyncExecutor())

• @syrusakbary
• @jhgg
• @dittos

MIT License