Enum OutboxError 

#[non_exhaustive]
pub enum OutboxError {
    NoPool {
        name: &'static str,
    },
    Record {
        name: &'static str,
        record: &'static str,
        source: Error,
    },
    WriteLockHeld {
        name: &'static str,
        record: &'static str,
    },
    Recover {
        name: &'static str,
        record: &'static str,
        source: Error,
    },
    Republish {
        name: &'static str,
        record: &'static str,
        id: String,
        source: Box<dyn StdError + Send + Sync>,
    },
}

A failure of the outbox: a record it could not write or read, or a republish that did not reach the broker.

Examples

use ruststream::runtime::PublishError;
use ruststream_sqlx::outbox::{OutboxError, TrackedPublishError};

pub async fn serve(pool: PgPool) -> Result<(), Box<dyn std::error::Error + Send + Sync>> {
    let tracking = outbox! { pool: pool, "orders" => OrderOutbox };
    let broker = MemoryBroker::new().bindable();
    let egress = broker.bind(Publish);
    let running = RustStream::new(AppInfo::new("orders", "0.1.0"))
        .with_broker(broker, |b| {
            b.include(fulfil);
        })
        .start()
        .await?;
    let publisher = tracking.wrap(running.publisher(egress).await?);

    // The status an HTTP endpoint answers an order with.
    let status = match publisher.message(&OrderPlaced { id: 7 }).publish().await {
        Ok(()) => 202,
        // Recorded but not sent: the next startup sends it.
        Err(PublishError::Publish(TrackedPublishError::Publish(_))) => 202,
        // Neither recorded nor sent: the client sends the order again.
        Err(PublishError::Publish(TrackedPublishError::Outbox(OutboxError::Record { .. }))) => 503,
        Err(_) => 500,
    };
    tracing::info!(status, "order answered");

    running.shutdown().await?;
    Ok(())
}

Variants (Non-exhaustive)

Non-exhaustive enums could have additional variants added in future. Therefore, when matching against variants of non-exhaustive enums, an extra wildcard arm must be added to account for any future variants.

NoPool

A message under a registered name was published before the outbox had a pool.

Fields

name: &'static str

The registered name.

Record

The record of a published message was not written; the message was not sent.

Fields

name: &'static str

The registered name.

record: &'static str

The record type.

source: Error

The database’s error.

WriteLockHeld

A transactional handler on SQLite published a message under a registered name while its own delivery transaction held the database’s write lock, which the record needs; the message was not sent.

The transaction holds the lock from its first write through Tx, or from its begin in an immediate or exclusive mode, until the delivery settles. A transaction that took the lock as it began fails the publish at once. After a statement through Tx the record waits for the lock at most the pool’s acquire timeout, since SQLite tells whether that statement wrote only by the wait. Such a handler publishes its tracked messages before its first write.

Fields

name: &'static str

The registered name.

record: &'static str

The record type.

Recover

The unprocessed records of a name were not read at startup.

Fields

name: &'static str

The registered name.

record: &'static str

The record type.

source: Error

The database’s error.

Republish

A record read at startup was not published again.

Fields

name: &'static str

The registered name.

record: &'static str

The record type.

id: String

The record’s id.

source: Box<dyn StdError + Send + Sync>

The publisher’s error.

Trait Implementations

impl Debug for OutboxError

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Display for OutboxError

fn fmt(&self, __formatter: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Error for OutboxError

fn source(&self) -> Option<&(dyn Error + 'static)>

Returns the lower-level source of this error, if any.

fn description(&self) -> &str

👎Deprecated since 1.42.0:

use the Display impl or to_string()

fn cause(&self) -> Option<&dyn Error>

👎Deprecated since 1.33.0:

replaced by Error::source, which can support downcasting

fn provide<'a>(&'a self, request: &mut Request<'a>)

🔬This is a nightly-only experimental API. (error_generic_member_access)

Provides type-based access to context intended for error reports.