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jsonrpc.JsonRpcContext

A per-call context object. Middlewares receive it as their only argument; any code running inside a JSON-RPC call can obtain it via get_jsonrpc_context().

Attributes

  • entrypoint: Entrypoint — the entrypoint handling this call.
  • raw_request: Any — the parsed JSON-RPC request dict (not yet validated against JsonRpcRequest).
  • raw_response: dict | None — the response dict that will be sent back. Assigning a new value runs it through the on_raw_response normaliser: the id is taken from raw_request, exceptions are converted into an error response, unhandled exceptions are turned into InternalError. Mutating the existing dict in-place bypasses the normaliser.
  • exception: Exception | None — the exception raised by the method, if any.
  • is_unhandled_exception: bool — True if the exception was not a BaseError/HTTPException, i.e. it was converted to InternalError.
  • http_request: starlette.requests.Request — the wrapping HTTP request.
  • http_response: starlette.responses.Response — the HTTP response that will be returned.
  • background_tasks: fastapi.BackgroundTasks — the background task queue.
  • method_route: MethodRoute | None — the matched method route (or None if the request failed before dispatch).
  • request: JsonRpcRequest — a validated JsonRpcRequest (cached). Raises InvalidRequest if validation fails.

Helpers

from fastapi_jsonrpc import (
    get_jsonrpc_context,
    get_jsonrpc_request_id,
    get_jsonrpc_method,
)

ctx = get_jsonrpc_context()       # the current JsonRpcContext
rid = get_jsonrpc_request_id()    # value of "id" from the raw request
name = get_jsonrpc_method()       # value of "method" from the raw request

All three read from a contextvars.ContextVar set for the duration of the call, so they work from anywhere in your async call graph.

Middleware signature

JsonRpcMiddleware = Callable[[JsonRpcContext], AbstractAsyncContextManager]

Implementations are typically written with @asynccontextmanager:

@asynccontextmanager
async def my_middleware(ctx: jsonrpc.JsonRpcContext):
    # setup
    try:
        yield
    finally:
        # teardown — ctx.raw_response is populated here
        ...