Struct dataflow::source::PostgresSourceReader

pub struct PostgresSourceReader {
    source_name: String,
    connector: PostgresSourceConnector,
    lsn: PgLsn,
    metrics: PgSourceMetrics,
}

Information required to sync data from Postgres

Fields

source_name: String

Used to produce useful error messages

connector: PostgresSourceConnector

lsn: PgLsn

Our cursor into the WAL

metrics: PgSourceMetrics

Implementations

impl PostgresSourceReader

pub fn new(
    source_name: String,
    connector: PostgresSourceConnector,
    metrics: &SourceBaseMetrics
) -> Self

Constructs a new instance

async fn produce_snapshot<W: AsyncWrite + Unpin>(
    &mut self,
    snapshot_tx: &mut SourceTransaction<'_>,
    buffer: &mut W
) -> Result<(), ReplicationError>

Creates the replication slot and produces the initial snapshot of the data

After the initial snapshot has been produced it returns the name of the created slot and the LSN at which we should start the replication stream at.

async fn revert_snapshot<R: Read + Seek>(
    &self,
    snapshot_tx: &mut SourceTransaction<'_>,
    reader: R
) -> Result<(), Error>

Reverts a failed snapshot by deleting any processed rows from the dataflow.

fn row_from_tuple<'a, T>(
    &mut self,
    rel_id: u32,
    tuple_data: T
) -> Result<Row, Error> where
    T: IntoIterator<Item = &'a TupleData>, 

Converts a Tuple received in the replication stream into a Row instance. The logical replication protocol doesn’t use the binary encoding for column values so contrary to the initial snapshot here we need to parse the textual form of each column.

The old_tuple argument can be used as a source of data to use when encountering unchanged TOAST values.

async fn produce_replication(
    &mut self,
    timestamper: &Timestamper
) -> Result<(), ReplicationError>

Trait Implementations

impl SimpleSource for PostgresSourceReader

fn start<'life0, 'async_trait>(
    self,
    timestamper: &'life0 Timestamper
) -> Pin<Box<dyn Future<Output = Result<(), SourceError>> + Send + 'async_trait>> where
    'life0: 'async_trait,
    Self: 'async_trait, 

The top-level control of the state machine and retry logic