Struct dataflow_types::types::PersistStreamDesc

pub struct PersistStreamDesc {
    pub name: String,
    pub upper_seal_ts: u64,
    pub since_ts: u64,
}

Description of a single persistent stream.

Fields

name: String

Name of the persistent stream.

upper_seal_ts: u64

The current upper seal timestamp of this stream.

NOTE: This timestamp is determined when the coordinator starts up or when the source is initially created. When a source is actively writing to this stream, the seal timestamp will progress beyond this timestamp.

This is okay for now because we only want to allow one source instantiation for persistent sources, meaning the flow is usually this:

1. coordinator determines seal timestamp
2. seal timestamps for a source are sent to dataflow when rendering a source
3. coordinator (or anyone) never looks at this timestamp again.

And when we restart, we start from step 1., at which time we are guaranteed not to have a source running already.

since_ts: u64

The current compaction frontier (aka since) of this stream.

NOTE: This timestamp is determined when the coordinator starts up or when the source is initially created. When a source is actively writing to this stream and allowing compaction, this will progress beyond this timestamp.

This is okay for now because we only want to allow one source instantiation for persistent sources, meaning the flow is usually this:

1. coordinator determines since timestamp
2. timestamps for a source are sent to dataflow when rendering a source
3. coordinator (or anyone) never looks at this timestamp again.

And when we restart, we start from step 1., at which time we are guaranteed not to have a source running already.

Trait Implementations

impl Clone for PersistStreamDesc

fn clone(&self) -> PersistStreamDesc

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for PersistStreamDesc

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

Formats the value using the given formatter.

impl<'de> Deserialize<'de> for PersistStreamDesc

fn deserialize<__D>(__deserializer: __D) -> Result<Self, __D::Error> where
    __D: Deserializer<'de>, 

Deserialize this value from the given Serde deserializer.

impl Serialize for PersistStreamDesc

fn serialize<__S>(&self, __serializer: __S) -> Result<__S::Ok, __S::Error> where
    __S: Serializer, 

Serialize this value into the given Serde serializer.