Client API

GraphQLClient

class aiographql.client.GraphQLClient(endpoint: str, headers: Optional[Mapping[str, str]] = None, method: Optional[str] = None, schema: Optional[graphql.type.schema.GraphQLSchema] = None, session: Optional[aiohttp.client.ClientSession] = None)

Client implementation handling all interactions with a specified endpoint. The following example shows how to make a simple query.

client = GraphQLClient(
    endpoint="http://127.0.0.1:8080/v1/graphql",
    headers={"Authorization": "Bearer <token>"},
)
response: GraphQLResponse = await client.query("{ city { name } }")

You can also use an application scoped aiohttp.ClientSession throughout the life of the client as show below.

async with aiohttp.ClientSession() as session:
    client = GraphQLClient(
        endpoint="http://127.0.0.1:8080/v1/graphql",
        session=session
    )
Parameters:
  • endpoint – URI of graph api.
  • headers – Default headers to use for every request made by this client. By default the client adds ‘Content-Type: application/json’ and ‘Accept-Encoding: gzip’ to all requests. These can be overridden by specifying then here.
  • method – Default method to use when submitting a GraphQL request to the specified endpoint.
  • session – Optional aiohttp.ClientSession to use when making requests. This is expected to be externally managed.
get(request: aiographql.client.request.GraphQLRequest, headers: Optional[Dict[str, str]] = None, operation: Optional[str] = None, variables: Optional[Dict[str, Any]] = None, session: Optional[aiohttp.client.ClientSession] = None) → aiographql.client.response.GraphQLResponse

Helper method that wraps :method: GraphQLClient.query with method explicitly set as GraphQLQueryMethod.get.

Parameters:
  • request – Request to send to the GraphQL server.
  • headers – Additional headers to be set when sending HTTP request.
  • operation – GraphQL operation name to use if the GraphQLRequest.query contains named operations. This will override any default operation set.
  • variables – Query variables to set for the provided request. This will override the default values for any existing variables in the request if set.
  • session – Optional aiohttp.ClientSession to use for requests
Returns:

The resulting GraphQLResponse object.

get_schema(refresh: bool = False, headers: Optional[Dict[str, str]] = None) → graphql.type.schema.GraphQLSchema

Get the introspected schema for the endpoint used by this client. If an unexpired cache exists, this is returned unless the refresh parameter is set to True.

Parameters:
  • refresh – Refresh the cached schema by forcing an introspection of the GraphQL endpoint.
  • headers – Request headers
Returns:

The GraphQL schema as introspected. This maybe a previously cached value.

introspect(headers: Optional[Dict[str, str]] = None) → graphql.type.schema.GraphQLSchema

Introspect the GraphQL endpoint specified for this client and return a graphql.GraphQLSchema object specifying the schema associated with this endpoint.

Returns:GraphQL schema for the configured endpoint
post(request: aiographql.client.request.GraphQLRequest, headers: Optional[Dict[str, str]] = None, operation: Optional[str] = None, variables: Optional[Dict[str, Any]] = None, session: Optional[aiohttp.client.ClientSession] = None) → aiographql.client.response.GraphQLResponse

Helper method that wraps GraphQLClient.query with method explicitly set as GraphQLQueryMethod.post.

Parameters:
  • request – Request to send to the GraphQL server.
  • headers – Additional headers to be set when sending HTTP request.
  • operation – GraphQL operation name to use if the GraphQLRequest.query contains named operations. This will override any default operation set.
  • variables – Query variables to set for the provided request. This will override the default values for any existing variables in the request if set.
  • session – Optional aiohttp.ClientSession to use for requests
Returns:

The resulting GraphQLResponse object.

query(request: Union[aiographql.client.request.GraphQLRequest, str], method: Optional[str] = None, headers: Optional[Dict[str, str]] = None, operation: Optional[str] = None, variables: Optional[Dict[str, Any]] = None, session: Optional[aiohttp.client.ClientSession] = None) → aiographql.client.response.GraphQLResponse

Method to send provided GraphQLRequest to the configured endpoint as an HTTP request. This method handles the configuration of headers HTTP method specific handling of request parameters and/or data as required.

The order of precedence, least to greatest, of headers is as follows,
  1. client headers (GraphQLClient.headers)
  2. request headers (GraphQLRequest.headers)
  3. headers specified as method parameter

In accordance to the GraphQL specification, any non 2XX response is treated as an error and raises GraphQLTransactionException instance.

Parameters:
  • request – Request to send to the GraphQL server.
  • method – HTTP method to use when submitting request (POST/GET). If once is not specified, the client default (GraphQLClient.method) is used.
  • headers – Additional headers to be set when sending HTTP request.
  • operation – GraphQL operation name to use if the GraphQLRequest.query contains named operations. This will override any default operation set.
  • variables – Query variables to set for the provided request. This will override the default values for any existing variables in the request if set.
  • session – Optional aiohttp.ClientSession to use for requests
Returns:

The resulting response object.

subscribe(request: aiographql.client.request.GraphQLRequest, headers: Optional[Dict[str, str]] = None, operation: Optional[str] = None, variables: Optional[Dict[str, Any]] = None, callbacks: Union[cafeteria.asyncio.callbacks.CallbackRegistry, Dict[aiographql.client.subscription.GraphQLSubscriptionEventType, Union[Callable, Coroutine[T_co, T_contra, V_co], Callback, List[Union[Callable, Coroutine[T_co, T_contra, V_co], Callback]]]], None] = None, on_data: Union[Callable, Coroutine[T_co, T_contra, V_co], Callback, None] = None, on_error: Union[Callable, Coroutine[T_co, T_contra, V_co], Callback, None] = None, session: Optional[aiohttp.client.ClientSession] = None) → aiographql.client.subscription.GraphQLSubscription

Create and initialise a GraphQL subscription. Once subscribed and a known event is received, all registered callbacks for the event type is triggered with the aiographql.client.GraphQLSubscriptionEvent instance passed in the first argument.

The following example will start a subscription that prints all data events as it receives them.

# initialise and subscribe to events in the background
subscription: GraphQLSubscription = await client.subscribe(
    request="{ notifications: { id, summary } }",
    on_data=lambda event: print(f"Data: {event}"),
    on_error=lambda event: print(f"Error: {event}"),
)
# process events for 10 seconds then unsubscribe
await asyncio.wait(subscription.task, timeout=10)
subscription.unsubscribe()
Parameters:
  • request – Request to send to the GraphQL server.
  • headers – Additional headers to be set when sending HTTP request.
  • operation – GraphQL operation name to use if the GraphQLRequest.query contains named operations. This will override any default operation set.
  • variables – Query variables to set for the provided request. This will override the default values for any existing variables in the request if set.
  • session – Optional aiohttp.ClientSession to use for requests
  • callbacks – Custom callback registry mapping an event to one more more callback methods. If not provided, a new instance is created.
  • on_data – Callback to use when data event is received.
  • on_error – Callback to use when an error occurs.
  • session – Optional session to use for connecting the graphql endpoint, if one is not provided, a new session is created for the duration of the subscription.
Returns:

The resulting GraphQLResponse object.

Returns:

The initialised subscription.

validate(request: aiographql.client.request.GraphQLRequest, schema: Optional[graphql.type.schema.GraphQLSchema] = None, headers: Optional[Dict[str, str]] = None, force: bool = False) → None

Validate a given request against a schema (provided or fetched). Validation is skipped if the request’s validate property is set to False unless forced.

Parameters:
  • request – Request that is to be validated.
  • schema – Schema against which provided request should be validated, if different from GraphQLRequest.schema or as fetched from the client endpoint.
  • headers – Headers to be set when fetching the schema from the client endpoint. If provided, request headers are ignored.
  • force – Force validation even if the provided request has validation disabled.

GraphQLSubscription

class aiographql.client.GraphQLSubscription(request: GraphQLRequest, headers: InitVar[Optional[Dict[str, str]]] = None, operation: InitVar[Optional[str]] = None, variables: InitVar[Optional[Dict[str, Any]]] = None, callbacks: Optional[CallbacksType] = <factory>, stop_event_types: List[GraphQLSubscriptionEventType] = <factory>)

Subscription container, with an attached cafeteria.asyncio.callbacks.CallbackRegistry. When subscribed, the task will be populated with the asyncio.Task instance.

By default the subscription will be stopped, if an error, connection error or complete (GraphQLSubscriptionEventType) is received.

Subscription instances are intended to be used as immutable objects. However, callbacks and stop_event_types can be updated after initialisation.

Parameters:
  • id – A unique subscription identifier that will be passed into any events generated by this subscription.
  • callbacks – A CallbackRegistry containing a mapping of GraphQLSubscriptionEventType callback methods to trigger.
  • stop_event_types – Events that cause the subscription to stop. By default, connection error, query error or connection complete events received are considered stop events.
active() → bool

Check if the subscription is active.

Returns:True if subscribed and active.
connection_init_request() → Dict[str, Any]

Connection init payload to use when initiating a new subscription.

Returns:Connection initialise payload.
connection_start_request() → Dict[str, Any]

Connection start payload to use when starting a subscription.

Returns:Connection start payload.
connection_stop_request() → Dict[str, Any]

Connection stop payload to use when stopping a subscription.

Returns:Connection stop payload.
handle(event: aiographql.client.subscription.GraphQLSubscriptionEvent) → NoReturn

Helper method to dispatch any configured callbacks for the specified event type.

Parameters:event – Event to dispatch callbacks for.
is_stop_event(event: aiographql.client.subscription.GraphQLSubscriptionEvent) → bool

Check if the provided event is configured as a stop even for this subscription.

Parameters:event – Event to check.
Returns:True if event is in stop_event_types.
subscribe(endpoint: str, force: bool = False, session: Optional[aiohttp.client.ClientSession] = None) → None

Create a websocket subscription and set internal task.

Parameters:
  • endpoint – GraphQL endpoint to subscribe to
  • force – Force re-subscription if already subscribed
  • session – Optional session to use for requests
unsubscribe() → None

Unsubscribe current websocket subscription if active and clear internal task.

Data Containers

GraphQLRequest

class aiographql.client.GraphQLRequest(query: str, operation: InitVar[Optional[str]] = None, variables: Dict[str, Any] = <factory>, validate: bool = True, headers: Dict[str, str] = <factory>)

GraphQL Request object that can be reused or used to store multiple named queries with default operationName`, *variables and header to use.

Parameters:
  • query – GraphQL query string.
  • operation – Optional name of operation to use from the query.
  • variables – Variable dictionary pass with the query to the server.
  • validate – If True, the request query is validated against the latest available schema from the server.
  • headers – Headers to use, in addition to client default headers when making the HTTP request.

GraphQLResponse

class aiographql.client.GraphQLResponse(request: GraphQLRequest, headers: InitVar[Optional[Dict[str, str]]] = None, operation: InitVar[Optional[str]] = None, variables: InitVar[Optional[Dict[str, Any]]] = None, json: Dict[str, Any] = <factory>)

GraphQL Response object wrapping response data and any errors. This object also contains the a copy of the GraphQLRequest that produced this response.

data

The data payload the server responded with.

errors

A list of GraphQLError objects if server responded with query errors.

query

The query string used to produce this response.

GraphQLSubscriptionEvent

class aiographql.client.GraphQLSubscriptionEvent(request: GraphQLRequest, headers: InitVar[Optional[Dict[str, str]]] = None, operation: InitVar[Optional[str]] = None, variables: InitVar[Optional[Dict[str, Any]]] = None, json: Dict[str, Any] = <factory>, subscription_id: Optional[str] = None)

GraphQL subscription event wrapping the payload received from the server.

Parameters:subscription_id – The id of the subscription that generated this event.
id

The id of the event, if available.

payload

The id of the subscription that generated this event.

type

The type of event (GraphQLSubscriptionEventType).

GraphQLError

class aiographql.client.GraphQLError(extensions: Dict[str, Any] = <factory>, locations: Optional[List[Dict[str, int]]] = None, message: Optional[str] = None, path: Optional[List[Union[str, int]]] = None)

GraphQL error response object.

locations = None
message = None
path = None

Constants

GraphqQLQueryMethod

class aiographql.client.GraphQLQueryMethod(post: 'str' = 'post', get: 'str' = 'get')
get = 'get'
post = 'post'

GraphQLSubscriptionEventType

class aiographql.client.GraphQLSubscriptionEventType

GraphQL Subscription Event Types

COMPLETE = 'complete'
CONNECTION_ACK = 'connection_ack'
CONNECTION_ERROR = 'connection_error'
CONNECTION_INIT = 'connection_init'
CONNECTION_TERMINATE = 'connection_terminate'
DATA = 'data'
ERROR = 'error'
KEEP_ALIVE = 'ka'
START = 'start'
STOP = 'stop'

Exceptions

GraphQLClientException

class aiographql.client.GraphQLClientException

GraphQLClientValidationException

class aiographql.client.GraphQLClientValidationException(*args)

GraphQLRequestException

class aiographql.client.GraphQLRequestException(response: GraphQLResponse)

GraphQLIntrospectionException

class aiographql.client.GraphQLIntrospectionException(message: Optional[str] = None)