Enum ErrorHandler

pub enum ErrorHandler {
    Halt(&'static str),
    Signal(Rc<dyn Fn(Error) + 'static>),
}

Many dataflows, including the Persist source, encounter errors that are neither data-plane errors (a la SourceData) nor bugs. This includes:

• lease timeouts: the source has failed to heartbeat, the lease timed out, and our inputs are GCed away. (But we’d be able to use the compaction output if we restart.)
• external transactions: our Kafka transaction has failed, and we can’t re-create it without re-ingesting a bunch of data we no longer have in memory. (But we could do on restart.)

It would be an error to simply exit from our dataflow operator, since that allows timely frontiers to advance, which signals progress that we haven’t made. So we report the error and attempt to trigger a restart: either directly (via a halt!) or indirectly with a callback.

Variants

Halt(&'static str)

Halt the process on error.

Signal(Rc<dyn Fn(Error) + 'static>)

Signal an error to a higher-level supervisor.

Implementations

impl ErrorHandler

pub fn signal(signal_fn: impl Fn(Error) + 'static) -> Self

Returns a new error handler that uses the provided function to signal an error.

pub async fn report_and_stop(&self, error: Error) -> !

Signal an error to an error handler. This function never returns: logically it blocks until restart, though that restart might be sooner (if halting) or later (if triggering a dataflow restart, for example).

Trait Implementations

impl Clone for ErrorHandler

fn clone(&self) -> ErrorHandler

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for ErrorHandler

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

Formats the value using the given formatter.