Metadata-Version: 2.1
Name: cannula
Version: 0.0.2
Summary: Async GraphQL Helper Library
Home-page: https://github.com/rmyers/cannula
Author: Robert Myers
Author-email: robert@julython.org
License: MIT License
Description: # Cannula
        
        [![CircleCI](https://circleci.com/gh/rmyers/cannula.svg?style=shield)](https://circleci.com/gh/rmyers/cannula)
        [![Documentation Status](https://readthedocs.org/projects/cannula/badge/?version=latest)](https://cannula.readthedocs.io/en/latest/?badge=latest)
        
        > GraphQL for people who like Python!
        
        * [Why Cannula](#why)
        * [Installation](#install)
        * [Quick Start](#start)
        * [Examples](#examples)
        * [Documentation](https://cannula.readthedocs.io/)
        
        <h2 id="why">Why Cannula?</h2>
        
        We wanted to make the world a better place, but we are programmers so we settled
        on making the web fun again. Too much attention has been given to Javascript
        client libraries. They all seem to compete on size and speed and features but
        most of them do not solve any of the actual problems you have. So while the
        todo application is quick and easy to follow the hard parts take a long time
        to complete.
        
        Now a days if you want a fancy single page application you need to invest a
        good week or so planning out all the tools you will need to assemble your site.
        Every decision is full of sorrow and doubt as you google for the latest trends
        or how to setup unit tests. Or searching for a bootstrapped version of the
        library you like.
        
        Using GraphQL you can simplify your web application stack and reduce
        dependencies to achieve the same customer experience without regret. By using
        just a few core libraries you can increase productivity and make your
        application easier to maintain.
        
        Our Philosophy:
        1. Make your site easy to maintain.
        2. Document your code.
        3. Don't lock yourself into a framework.
        4. Be happy!
        
        <h2 id="install">Installation</h2>
        
        Requires Python 3.6 or greater! The only dependency is
        [graphql-core-next](https://graphql-core-next.readthedocs.io/en/latest/).
        
        ```bash
        pip3 install cannula
        ```
        
        <h2 id="start">Quick Start</h2>
        
        Here is a small [hello world example](examples/hello.py):
        
        ```python
        import logging
        import typing
        import sys
        
        import cannula
        from cannula.middleware import DebugMiddleware
        
        SCHEMA = cannula.gql("""
          type Message {
            text: String
          }
          type Query {
            hello(who: String): Message
          }
        """)
        
        logging.basicConfig(level=logging.DEBUG)
        
        api = cannula.API(
          __name__,
          schema=SCHEMA,
          middleware=[
            DebugMiddleware()
          ]
        )
        
        
        class Message(typing.NamedTuple):
            text: str
        
        
        # The query resolver takes a source and info objects
        # and any arguments defined by the schema. Here we
        # only accept a single argument `who`.
        @api.resolver('Query')
        async def hello(source, info, who):
            return Message(f"Hello, {who}!")
        
        # Pre-parse your query to speed up your requests.
        # Here is an example of how to pass arguments to your
        # query functions.
        SAMPLE_QUERY = cannula.gql("""
          query HelloWorld ($who: String!) {
            hello(who: $who) {
              text
            }
          }
        """)
        
        
        who = 'world'
        if len(sys.argv) > 1:
            who = sys.argv[1]
        
        print(api.call_sync(SAMPLE_QUERY, variables={'who': who}))
        ```
        
        Now you should see the results if you run the sample on the command line:
        
        ```bash
        $ python3 examples/hello.py
        DEBUG:asyncio:Using selector: KqueueSelector
        DEBUG:cannula.schema:Adding default empty Mutation type
        DEBUG:cannula.middleware.debug:Resolving Query.hello expecting type Message
        DEBUG:cannula.middleware.debug:Field Query.hello resolved: Message(text='Hello, world!') in 0.000108 seconds
        DEBUG:cannula.middleware.debug:Resolving Message.text expecting type String
        DEBUG:cannula.middleware.debug:Field Message.text resolved: 'Hello, world!' in 0.000067 seconds
        ExecutionResult(
          data={'hello': {'text': 'Hello, world!'}},
          errors=None
        )
        
        $ python3 examples/hello.py Bob
        DEBUG:asyncio:Using selector: KqueueSelector
        DEBUG:cannula.schema:Adding default empty Mutation type
        DEBUG:cannula.middleware.debug:Resolving Query.hello expecting type Message
        DEBUG:cannula.middleware.debug:Field Query.hello resolved: Message(text='Hello, Bob!') in 0.000104 seconds
        DEBUG:cannula.middleware.debug:Resolving Message.text expecting type String
        DEBUG:cannula.middleware.debug:Field Message.text resolved: 'Hello, Bob!' in 0.000101 seconds
        ExecutionResult(
          data={'hello': {'text': 'Hello, Bob!'}},
          errors=None
        )
        ```
        
        But what about Django integration or flask?
        
        ```python
        # pip install channels, Django
        import cannula
        from channels.db import database_sync_to_async
        from django.contrib.auth.models import User
        
        schema = cannula.gql("""
          type User {
            username: String   # Only expose the fields you actually use
            first_name: String
            last_name: String
            made_up_field: String
          }
          extend type Query {
            getUserById(user_id: String): User
          }
        """)
        
        @api.query()
        async def getUserById(source, info, user_id):
            return await get_user(user_id)
        
        @database_sync_to_async
        def get_user(user_id):
            return User.objects.get(pk=user_id)
        
        @api.resolve('User')
        async def made_up_field(source, info):
            return f"{source.get_full_name()} is a lying lier there is no 'made_up_field'"
        ```
        
        Since GraphQL is agnostic about where or how you store your data all you need
        to do is provide a function to resolve a query. The results you return just
        need to match the schema and you are done.
        
        Django and sqlalchemy already provide tools to query the database. And they
        work quite well. Or you may choose to use an async database library to make
        concurrent requests work even better. Try them all and see what works best for
        your team and your use case.
        
        <h2 id="examples">Examples and Documentation</h2>
        
        * [hello world](examples/hello.py)
        * [using mocks](examples/mocks.py)
        * [Real World Example](examples/cloud)
        
        [Documentation](https://cannula.readthedocs.io/)
        
Keywords: graphql
Platform: UNKNOWN
Classifier: Development Status :: 4 - Beta
Classifier: Programming Language :: Python :: 3.6
Classifier: License :: OSI Approved :: MIT License
Classifier: Operating System :: OS Independent
Description-Content-Type: text/markdown
