<h3 id="chan">Channel communication</h3>

<p>
Channel communication is the main method of synchronization
between goroutines.  Each send on a particular channel
is matched to a corresponding receive from that channel,
usually in a different goroutine.
</p>

<p class="rule">
A send on a channel is synchronized before the completion of the
corresponding receive from that channel.
</p>

<p>
This program:
</p>

app = FastAPI()


def write_notification(email: str, message=""):
    with open("log.txt", mode="w") as email_file:
        content = f"notification for {email}: {message}"
        email_file.write(content)


@app.post("/send-notification/{email}")
async def send_notification(email: str, background_tasks: BackgroundTasks):
    background_tasks.add_task(write_notification, email, message="some notification")

    ```
    """

    def __init__(
        self,
        status_code: Annotated[
            int,
            Doc(
                """
                HTTP status code to send to the client.
                """
            ),
        ],
        detail: Annotated[
            Any,
            Doc(
                """

def get_query(background_tasks: BackgroundTasks, q: str | None = None):
    if q:
        message = f"found query: {q}\n"
        background_tasks.add_task(write_log, message)
    return q


@app.post("/send-notification/{email}")
async def send_notification(
    email: str, background_tasks: BackgroundTasks, q: str = Depends(get_query)
):
    message = f"message to {email}\n"
    background_tasks.add_task(write_log, message)

    /**
     * @param cap
     * @return whether the capabiltiy is present
     * @throws CIFSException
     */
    boolean hasCapability ( int cap ) throws CIFSException;


    /**
     * @return the send buffer size of the underlying connection
     * @throws CIFSException
     */
    int getSendBufferSize () throws CIFSException;


    /**
     * @return the receive buffer size of the underlying connection

        "webhooks": {
            "new-subscription": {
                "post": {
                    "summary": "New Subscription",
                    "description": "When a new user subscribes to your service we'll send you a POST request with this\ndata to the URL that you register for the event `new-subscription` in the dashboard.",
                    "operationId": "new_subscriptionnew_subscription_post",
                    "requestBody": {

	auditTotalMessages     = "total_messages"
	targetID               = "target_id"
)

var (
	auditFailedMessagesMD = NewCounterMD(auditFailedMessages,
		"Total number of messages that failed to send since start",
		targetID)
	auditTargetQueueLengthMD = NewGaugeMD(auditTargetQueueLength,
		"Number of unsent messages in queue for target",
		targetID)
	auditTotalMessagesMD = NewCounterMD(auditTotalMessages,

        }
        catch ( Exception e ) {
            this.treeHandle.release();
            throw e;
        }

    }


    private FileEntry open () throws CIFSException {
        this.treeHandle.send(this.request, this.response);
        checkStatus();
        FileEntry n = advance();
        if ( n == null ) {
            doClose();
        }
        return n;
    }


    /**

    from docs_src.background_tasks.tutorial002_py310 import app

    client = TestClient(app)
    log = Path("log.txt")
    if log.is_file():
        os.remove(log)  # pragma: no cover
    response = client.post("/send-notification/******@****.***?q=some-query")
    assert response.status_code == 200, response.text
    assert response.json() == {"message": "Message sent"}
    with open("./log.txt") as f:

            Doc(
                """
                By default, if no HTTP Authorization header is provided, required for
                OpenID Connect authentication, it will automatically cancel the request
                and send the client an error.

                If `auto_error` is set to `False`, when the HTTP Authorization header
                is not available, instead of erroring out, the dependency result will
                be `None`.