py-gql 0.2.0

Comprehensive GraphQL implementation for Python.

py-gql

py-gql_is a pure python GraphQL implementation aimed at creating GraphQL servers.

It supports:

• Parsing the GraphQL query language and schema definition language.
• Building a GraphQL type schema programatically and from Schema Definition files (including support for schema directives).
• Validating and Executing a GraphQL request against a type schema.

Quick links

• Source Code & Issue Tracker
• PyPI project
• Read The Docs
• Changelog

Installation

pip install py-gql

For more details see install.rst.

Usage & Examples

Hello World

from py_gql import build_schema, graphql_blocking

schema = build_schema(
    """
    type Query {
        hello(value: String = "world"): String!
    }
    """
)


@schema.resolver("Query.hello")
def resolve_hello(*_, value):
    return f"Hello {value}!"


result = graphql_blocking(schema, '{ hello(value: "Foo") }')
assert result.response() == {
    "data": {
        "hello": "Hello Foo!"
    }
}

For more usage examples, you can refer to the User Guide and some more involved examples available in the examples folder.

The tests should also provide some contrived exmaples.

Goals & Status

This project was initially born as an experiment / learning project following some frustration with with graphql-core and Graphene I encountered at work.

The main goals were originally to:

• Get a deeper understanding of GraphQL

• Provide an alternative to graphql-core which:

  • tracks the latest version of the spec (which graphql-core didn't)
  • does so without being a port of the JS code which leads to some weird edge case when we tried to extend the library
  • keeps support for Python 2 (which graphql-core-next) didn't.
  • (subjective) attempts to be a bit more usable for our use cases, the ideal result would sit somewhere in between Graphene and graphql-core
  • makes it easier for us to build / include some extra tooling such as custom tracing, custom validation and SDL based tools.

After going through a couple iterations, it should be ready ready for general use to create GraphQL servers; with the notable omissions of:

• Subscription support
• Python 2 support has been dropped
• Middleware have been dropped pending an iteration on the API (and consequently tracers are not supported either)

Development setup

Make sure you are using Python 3.6+.

Clone this repo and create a virtualenv before installing the development dependencies:

git clone [e-mail]:lirsacc/py-gql.git
python -m venv $WORKON_HOME/py-gql --copies
pip install -U -r dev-requirements.txt

From there, most development tasks are available through invoke.

Use inv -l to list all available tasks and inv {TASKS} --help to get help on a specific task.