gql

The special example for gql users.

Step 1

Download GraphQL schema from https://countries.trevorblades.com/ and run graphql2python with her:

# graphql2python.yaml
schema: ./schema.graphql
output: ./model.py
options:
  each_field_optional: true
  scalar_pytypes:
    Boolean: bool

You will receive the following file model.py:

"""Auto-generated by graphql2python."""

# pylint: disable-all
# mypy: ignore-errors

import enum
import typing as _t
from datetime import date, datetime

from pydantic import BaseModel, Field

__all__ = [
    "GraphQLBaseModel",
    # scalars
    "Boolean",
    "ID",
    "String",
    "_Any",
    # enums
    # unions
    "_Entity",
    # interfaces
    # objects
    "Continent",
    "Country",
    "Language",
    "State",
    "_Service",
]


class GraphQLBaseModel(BaseModel):
    """Base Model for GraphQL object."""

    class Config:
        allow_population_by_field_name = True
        json_encoders = {
            # custom output conversion for datetime
            datetime: lambda dt: dt.isoformat()
        }
        smart_union = True


# The `Boolean` scalar type represents `true` or `false`.
Boolean = bool


# The `ID` scalar type represents a unique identifier, often used to refetch an object or as key for a cache. The ID
# type appears in a JSON response as a String; however, it is not intended to be human-readable. When expected as an
# input type, any string (such as `"4"`) or integer (such as `4`) input value will be accepted as an ID.
ID = str


# The `String` scalar type represents textual data, represented as UTF-8 character sequences. The String type is most
# often used by GraphQL to represent free-form human-readable text.
String = str


# A Scalar type
# See https://graphql.org/learn/schema/#scalar-types
_Any = str


# A Union type
# See https://graphql.org/learn/schema/#union-types
_Entity = _t.Union[
    'Continent',
    'Country',
    'Language',
]


class Continent(GraphQLBaseModel):
    """
    An Object type
    See https://graphql.org/learn/schema/#object-types-and-fields
    """
    code: _t.Optional['ID'] = Field(default=None)
    countries: _t.Optional[_t.List['Country']] = Field(default_factory=list)
    name: _t.Optional['String'] = Field(default=None)
    typename__: _t.Literal["Continent"] = Field(default="Continent", alias="__typename")


class Country(GraphQLBaseModel):
    """
    An Object type
    See https://graphql.org/learn/schema/#object-types-and-fields
    """
    capital: _t.Optional['String'] = Field(default=None)
    code: _t.Optional['ID'] = Field(default=None)
    continent: _t.Optional['Continent'] = Field(default=None)
    currency: _t.Optional['String'] = Field(default=None)
    emoji: _t.Optional['String'] = Field(default=None)
    emojiU: _t.Optional['String'] = Field(default=None)
    languages: _t.Optional[_t.List['Language']] = Field(default_factory=list)
    name: _t.Optional['String'] = Field(default=None)
    native: _t.Optional['String'] = Field(default=None)
    phone: _t.Optional['String'] = Field(default=None)
    states: _t.Optional[_t.List['State']] = Field(default_factory=list)
    typename__: _t.Literal["Country"] = Field(default="Country", alias="__typename")


class Language(GraphQLBaseModel):
    """
    An Object type
    See https://graphql.org/learn/schema/#object-types-and-fields
    """
    code: _t.Optional['ID'] = Field(default=None)
    name: _t.Optional['String'] = Field(default=None)
    native: _t.Optional['String'] = Field(default=None)
    rtl: _t.Optional['Boolean'] = Field(default=None)
    typename__: _t.Literal["Language"] = Field(default="Language", alias="__typename")


class State(GraphQLBaseModel):
    """
    An Object type
    See https://graphql.org/learn/schema/#object-types-and-fields
    """
    code: _t.Optional['String'] = Field(default=None)
    country: _t.Optional['Country'] = Field(default=None)
    name: _t.Optional['String'] = Field(default=None)
    typename__: _t.Literal["State"] = Field(default="State", alias="__typename")


class _Service(GraphQLBaseModel):
    """
    An Object type
    See https://graphql.org/learn/schema/#object-types-and-fields
    """
    sdl: _t.Optional['String'] = Field(default=None)
    typename__: _t.Literal["_Service"] = Field(default="_Service", alias="__typename")


Continent.update_forward_refs()
Country.update_forward_refs()
Language.update_forward_refs()
State.update_forward_refs()
_Service.update_forward_refs()

Step 2

Create the queries with graphql-query (https://github.com/denisart/graphql-query):

# queries.py
from graphql_query import Operation, Query

continents = Query(name="continents", fields=["code", "name"])
getContinents = Operation(
    type="query",
    name="getContinents",
    queries=[continents]
)

Step 3

Install gql and do magic

from gql import gql, Client
from gql.transport.aiohttp import AIOHTTPTransport

from queries import getContinents
from model import Continent

# Select your transport with a defined url endpoint
transport = AIOHTTPTransport(url="https://countries.trevorblades.com/")

# Create a GraphQL client using the defined transport
client = Client(transport=transport, fetch_schema_from_transport=True)

# Provide a GraphQL query
query = gql(getContinents.render())

# Execute the query on the transport
result = client.execute(query)
continents = [
    Continent.parse_obj(continent)
    for continent in result[getContinents.queries[0].name]
]

print(continents)
# [Continent(code='AF', countries=[], name='Africa', typename__='Continent'), Continent(code='AN', countries=[], name='Antarctica', typename__='Continent'), Continent(code='AS', countries=[], name='Asia', typename__='Continent'), Continent(code='EU', countries=[], name='Europe', typename__='Continent'), Continent(code='NA', countries=[], name='North America', typename__='Continent'), Continent(code='OC', countries=[], name='Oceania', typename__='Continent'), Continent(code='SA', countries=[], name='South America', typename__='Continent')]