risingwave_stream/executor/backfill/cdc/cdc_backfill.rs
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// Copyright 2024 RisingWave Labs
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
use std::pin::Pin;
use either::Either;
use futures::stream;
use futures::stream::select_with_strategy;
use itertools::Itertools;
use risingwave_common::array::DataChunk;
use risingwave_common::bail;
use risingwave_common::catalog::ColumnDesc;
use risingwave_common::row::RowExt;
use risingwave_common::util::iter_util::ZipEqFast;
use risingwave_connector::parser::{
ByteStreamSourceParser, DebeziumParser, DebeziumProps, EncodingProperties, JsonProperties,
ProtocolProperties, SourceStreamChunkBuilder, SpecificParserConfig,
};
use risingwave_connector::source::cdc::external::CdcOffset;
use risingwave_connector::source::{SourceColumnDesc, SourceContext};
use rw_futures_util::pausable;
use crate::executor::backfill::cdc::state::CdcBackfillState;
use crate::executor::backfill::cdc::upstream_table::external::ExternalStorageTable;
use crate::executor::backfill::cdc::upstream_table::snapshot::{
SnapshotReadArgs, UpstreamTableRead, UpstreamTableReader,
};
use crate::executor::backfill::utils::{
get_cdc_chunk_last_offset, get_new_pos, mapping_chunk, mapping_message, mark_cdc_chunk,
};
use crate::executor::backfill::CdcScanOptions;
use crate::executor::monitor::CdcBackfillMetrics;
use crate::executor::prelude::*;
use crate::executor::UpdateMutation;
use crate::task::CreateMviewProgressReporter;
/// `split_id`, `is_finished`, `row_count`, `cdc_offset` all occupy 1 column each.
const METADATA_STATE_LEN: usize = 4;
pub struct CdcBackfillExecutor<S: StateStore> {
actor_ctx: ActorContextRef,
/// The external table to be backfilled
external_table: ExternalStorageTable,
/// Upstream changelog stream which may contain metadata columns, e.g. `_rw_offset`
upstream: Executor,
/// The column indices need to be forwarded to the downstream from the upstream and table scan.
output_indices: Vec<usize>,
/// The schema of output chunk, including additional columns if any
output_columns: Vec<ColumnDesc>,
/// State table of the `CdcBackfill` executor
state_impl: CdcBackfillState<S>,
// TODO: introduce a CdcBackfillProgress to report finish to Meta
// This object is just a stub right now
progress: Option<CreateMviewProgressReporter>,
metrics: CdcBackfillMetrics,
/// Rate limit in rows/s.
rate_limit_rps: Option<u32>,
options: CdcScanOptions,
}
impl<S: StateStore> CdcBackfillExecutor<S> {
#[allow(clippy::too_many_arguments)]
pub fn new(
actor_ctx: ActorContextRef,
external_table: ExternalStorageTable,
upstream: Executor,
output_indices: Vec<usize>,
output_columns: Vec<ColumnDesc>,
progress: Option<CreateMviewProgressReporter>,
metrics: Arc<StreamingMetrics>,
state_table: StateTable<S>,
rate_limit_rps: Option<u32>,
options: CdcScanOptions,
) -> Self {
let pk_indices = external_table.pk_indices();
let upstream_table_id = external_table.table_id().table_id;
let state_impl = CdcBackfillState::new(
upstream_table_id,
state_table,
pk_indices.len() + METADATA_STATE_LEN,
);
let metrics = metrics.new_cdc_backfill_metrics(external_table.table_id(), actor_ctx.id);
Self {
actor_ctx,
external_table,
upstream,
output_indices,
output_columns,
state_impl,
progress,
metrics,
rate_limit_rps,
options,
}
}
fn report_metrics(
metrics: &CdcBackfillMetrics,
snapshot_processed_row_count: u64,
upstream_processed_row_count: u64,
) {
metrics
.cdc_backfill_snapshot_read_row_count
.inc_by(snapshot_processed_row_count);
metrics
.cdc_backfill_upstream_output_row_count
.inc_by(upstream_processed_row_count);
}
#[try_stream(ok = Message, error = StreamExecutorError)]
async fn execute_inner(mut self) {
// The indices to primary key columns
let pk_indices = self.external_table.pk_indices().to_vec();
let pk_order = self.external_table.pk_order_types().to_vec();
let table_id = self.external_table.table_id().table_id;
let upstream_table_name = self.external_table.qualified_table_name();
let schema_table_name = self.external_table.schema_table_name().clone();
let external_database_name = self.external_table.database_name().to_owned();
let upstream_table_reader = UpstreamTableReader::new(self.external_table);
let additional_columns = self
.output_columns
.iter()
.filter(|col| col.additional_column.column_type.is_some())
.cloned()
.collect_vec();
let mut upstream = self.upstream.execute();
// Current position of the upstream_table storage primary key.
// `None` means it starts from the beginning.
let mut current_pk_pos: Option<OwnedRow>;
// Poll the upstream to get the first barrier.
let first_barrier = expect_first_barrier(&mut upstream).await?;
let mut is_snapshot_paused = first_barrier.is_pause_on_startup();
let first_barrier_epoch = first_barrier.epoch;
// The first barrier message should be propagated.
yield Message::Barrier(first_barrier);
let mut rate_limit_to_zero = self.rate_limit_rps.is_some_and(|val| val == 0);
// Check whether this parallelism has been assigned splits,
// if not, we should bypass the backfill directly.
let mut state_impl = self.state_impl;
let mut upstream = transform_upstream(upstream, &self.output_columns)
.boxed()
.peekable();
state_impl.init_epoch(first_barrier_epoch).await?;
// restore backfill state
let state = state_impl.restore_state().await?;
current_pk_pos = state.current_pk_pos.clone();
let to_backfill = !self.options.disable_backfill && !state.is_finished;
// Keep track of rows from the snapshot.
let mut total_snapshot_row_count = state.row_count as u64;
let mut last_binlog_offset: Option<CdcOffset> = state
.last_cdc_offset
.map_or(upstream_table_reader.current_cdc_offset().await?, Some);
let offset_parse_func = upstream_table_reader
.inner()
.table_reader()
.get_cdc_offset_parser();
let mut consumed_binlog_offset: Option<CdcOffset> = None;
tracing::info!(
table_id,
upstream_table_name,
initial_binlog_offset = ?last_binlog_offset,
?current_pk_pos,
is_finished = state.is_finished,
is_snapshot_paused,
snapshot_row_count = total_snapshot_row_count,
rate_limit = self.rate_limit_rps,
disable_backfill = self.options.disable_backfill,
snapshot_interval = self.options.snapshot_interval,
snapshot_batch_size = self.options.snapshot_batch_size,
"start cdc backfill",
);
// CDC Backfill Algorithm:
//
// When the first barrier comes from upstream:
// - read the current binlog offset as `binlog_low`
// - start a snapshot read upon upstream table and iterate over the snapshot read stream
// - buffer the changelog event from upstream
//
// When a new barrier comes from upstream:
// - read the current binlog offset as `binlog_high`
// - for each row of the upstream change log, forward it to downstream if it in the range
// of [binlog_low, binlog_high] and its pk <= `current_pos`, otherwise ignore it
// - reconstruct the whole backfill stream with upstream changelog and a new table snapshot
//
// When a chunk comes from snapshot, we forward it to the downstream and raise
// `current_pos`.
// When we reach the end of the snapshot read stream, it means backfill has been
// finished.
//
// Once the backfill loop ends, we forward the upstream directly to the downstream.
if to_backfill {
// drive the upstream changelog first to ensure we can receive timely changelog event,
// otherwise the upstream changelog may be blocked by the snapshot read stream
let _ = Pin::new(&mut upstream).peek().await;
// wait for a barrier to make sure the backfill starts after upstream source
#[for_await]
for msg in upstream.by_ref() {
match msg? {
Message::Barrier(barrier) => {
match barrier.mutation.as_deref() {
Some(crate::executor::Mutation::Pause) => {
is_snapshot_paused = true;
tracing::info!(
table_id,
upstream_table_name,
"snapshot is paused by barrier"
);
}
Some(crate::executor::Mutation::Resume) => {
is_snapshot_paused = false;
tracing::info!(
table_id,
upstream_table_name,
"snapshot is resumed by barrier"
);
}
_ => {
// ignore other mutations
}
}
// commit state just to bump the epoch of state table
state_impl.commit_state(barrier.epoch).await?;
yield Message::Barrier(barrier);
break;
}
Message::Chunk(ref chunk) => {
last_binlog_offset = get_cdc_chunk_last_offset(&offset_parse_func, chunk)?;
}
Message::Watermark(_) => {
// Ignore watermark
}
}
}
tracing::info!(table_id,
upstream_table_name,
initial_binlog_offset = ?last_binlog_offset,
?current_pk_pos,
is_snapshot_paused,
"start cdc backfill loop");
// the buffer will be drained when a barrier comes
let mut upstream_chunk_buffer: Vec<StreamChunk> = vec![];
'backfill_loop: loop {
let left_upstream = upstream.by_ref().map(Either::Left);
let mut snapshot_read_row_cnt: usize = 0;
let read_args = SnapshotReadArgs::new(
current_pk_pos.clone(),
self.rate_limit_rps,
pk_indices.clone(),
additional_columns.clone(),
schema_table_name.clone(),
external_database_name.clone(),
);
let right_snapshot = pin!(upstream_table_reader
.snapshot_read_full_table(read_args, self.options.snapshot_batch_size)
.map(Either::Right));
let (right_snapshot, snapshot_valve) = pausable(right_snapshot);
if is_snapshot_paused {
snapshot_valve.pause();
}
// Prefer to select upstream, so we can stop snapshot stream when barrier comes.
let mut backfill_stream =
select_with_strategy(left_upstream, right_snapshot, |_: &mut ()| {
stream::PollNext::Left
});
let mut cur_barrier_snapshot_processed_rows: u64 = 0;
let mut cur_barrier_upstream_processed_rows: u64 = 0;
let mut barrier_count: u32 = 0;
let mut pending_barrier = None;
#[for_await]
for either in &mut backfill_stream {
match either {
// Upstream
Either::Left(msg) => {
match msg? {
Message::Barrier(barrier) => {
// increase the barrier count and check whether need to start a new snapshot
barrier_count += 1;
let can_start_new_snapshot =
barrier_count == self.options.snapshot_interval;
if let Some(mutation) = barrier.mutation.as_deref() {
use crate::executor::Mutation;
match mutation {
Mutation::Pause => {
is_snapshot_paused = true;
snapshot_valve.pause();
}
Mutation::Resume => {
is_snapshot_paused = false;
snapshot_valve.resume();
}
Mutation::Throttle(some) => {
if let Some(new_rate_limit) =
some.get(&self.actor_ctx.id)
&& *new_rate_limit != self.rate_limit_rps
{
self.rate_limit_rps = *new_rate_limit;
rate_limit_to_zero = self
.rate_limit_rps
.is_some_and(|val| val == 0);
// update and persist current backfill progress without draining the buffered upstream chunks
state_impl
.mutate_state(
current_pk_pos.clone(),
last_binlog_offset.clone(),
total_snapshot_row_count,
false,
)
.await?;
state_impl.commit_state(barrier.epoch).await?;
yield Message::Barrier(barrier);
// rebuild the snapshot stream with new rate limit
continue 'backfill_loop;
}
}
Mutation::Update(UpdateMutation {
dropped_actors,
..
}) => {
if dropped_actors.contains(&self.actor_ctx.id) {
// the actor has been dropped, exit the backfill loop
tracing::info!(
table_id,
upstream_table_name,
"CdcBackfill has been dropped due to config change"
);
yield Message::Barrier(barrier);
break 'backfill_loop;
}
}
_ => (),
}
}
Self::report_metrics(
&self.metrics,
cur_barrier_snapshot_processed_rows,
cur_barrier_upstream_processed_rows,
);
// when processing a barrier, check whether can start a new snapshot
// if the number of barriers reaches the snapshot interval
if can_start_new_snapshot {
// staging the barrier
pending_barrier = Some(barrier);
tracing::debug!(
table_id,
?current_pk_pos,
?snapshot_read_row_cnt,
"Prepare to start a new snapshot"
);
// Break the loop for consuming snapshot and prepare to start a new snapshot
break;
} else {
// update and persist current backfill progress
state_impl
.mutate_state(
current_pk_pos.clone(),
last_binlog_offset.clone(),
total_snapshot_row_count,
false,
)
.await?;
state_impl.commit_state(barrier.epoch).await?;
// emit barrier and continue consume the backfill stream
yield Message::Barrier(barrier);
}
}
Message::Chunk(chunk) => {
// skip empty upstream chunk
if chunk.cardinality() == 0 {
continue;
}
let chunk_binlog_offset =
get_cdc_chunk_last_offset(&offset_parse_func, &chunk)?;
tracing::trace!(
"recv changelog chunk: chunk_offset {:?}, capactiy {}",
chunk_binlog_offset,
chunk.capacity()
);
// Since we don't need changelog before the
// `last_binlog_offset`, skip the chunk that *only* contains
// events before `last_binlog_offset`.
if let Some(last_binlog_offset) = last_binlog_offset.as_ref() {
if let Some(chunk_offset) = chunk_binlog_offset
&& chunk_offset < *last_binlog_offset
{
tracing::trace!(
"skip changelog chunk: chunk_offset {:?}, capacity {}",
chunk_offset,
chunk.capacity()
);
continue;
}
}
// Buffer the upstream chunk.
upstream_chunk_buffer.push(chunk.compact());
}
Message::Watermark(_) => {
// Ignore watermark during backfill.
}
}
}
// Snapshot read
Either::Right(msg) => {
match msg? {
None => {
tracing::info!(
table_id,
?last_binlog_offset,
?current_pk_pos,
"snapshot read stream ends"
);
// If the snapshot read stream ends, it means all historical
// data has been loaded.
// We should not mark the chunk anymore,
// otherwise, we will ignore some rows in the buffer.
for chunk in upstream_chunk_buffer.drain(..) {
yield Message::Chunk(mapping_chunk(
chunk,
&self.output_indices,
));
}
// backfill has finished, exit the backfill loop and persist the state when we recv a barrier
break 'backfill_loop;
}
Some(chunk) => {
// Raise the current position.
// As snapshot read streams are ordered by pk, so we can
// just use the last row to update `current_pos`.
current_pk_pos = Some(get_new_pos(&chunk, &pk_indices));
tracing::trace!(
"got a snapshot chunk: len {}, current_pk_pos {:?}",
chunk.cardinality(),
current_pk_pos
);
let chunk_cardinality = chunk.cardinality() as u64;
cur_barrier_snapshot_processed_rows += chunk_cardinality;
total_snapshot_row_count += chunk_cardinality;
yield Message::Chunk(mapping_chunk(
chunk,
&self.output_indices,
));
}
}
}
}
}
assert!(pending_barrier.is_some(), "pending_barrier must exist");
let pending_barrier = pending_barrier.unwrap();
// Here we have to ensure the snapshot stream is consumed at least once,
// since the barrier event can kick in anytime.
// Otherwise, the result set of the new snapshot stream may become empty.
// It maybe a cancellation bug of the mysql driver.
let (_, mut snapshot_stream) = backfill_stream.into_inner();
// skip consume the snapshot stream if it is paused or rate limit to 0
if !is_snapshot_paused
&& !rate_limit_to_zero
&& let Some(msg) = snapshot_stream
.next()
.instrument_await("consume_snapshot_stream_once")
.await
{
let Either::Right(msg) = msg else {
bail!("BUG: snapshot_read contains upstream messages");
};
match msg? {
None => {
tracing::info!(
table_id,
?last_binlog_offset,
?current_pk_pos,
"snapshot read stream ends in the force emit branch"
);
// End of the snapshot read stream.
// Consume the buffered upstream chunk without filtering by `binlog_low`.
for chunk in upstream_chunk_buffer.drain(..) {
yield Message::Chunk(mapping_chunk(chunk, &self.output_indices));
}
// mark backfill has finished
state_impl
.mutate_state(
current_pk_pos.clone(),
last_binlog_offset.clone(),
total_snapshot_row_count,
true,
)
.await?;
// commit state because we have received a barrier message
state_impl.commit_state(pending_barrier.epoch).await?;
yield Message::Barrier(pending_barrier);
// end of backfill loop, since backfill has finished
break 'backfill_loop;
}
Some(chunk) => {
// Raise the current pk position.
current_pk_pos = Some(get_new_pos(&chunk, &pk_indices));
let row_count = chunk.cardinality() as u64;
cur_barrier_snapshot_processed_rows += row_count;
total_snapshot_row_count += row_count;
snapshot_read_row_cnt += row_count as usize;
tracing::debug!(
table_id,
?current_pk_pos,
?snapshot_read_row_cnt,
"force emit a snapshot chunk"
);
yield Message::Chunk(mapping_chunk(chunk, &self.output_indices));
}
}
}
// If the number of barriers reaches the snapshot interval,
// consume the buffered upstream chunks.
if let Some(current_pos) = ¤t_pk_pos {
for chunk in upstream_chunk_buffer.drain(..) {
cur_barrier_upstream_processed_rows += chunk.cardinality() as u64;
// record the consumed binlog offset that will be
// persisted later
consumed_binlog_offset =
get_cdc_chunk_last_offset(&offset_parse_func, &chunk)?;
yield Message::Chunk(mapping_chunk(
mark_cdc_chunk(
&offset_parse_func,
chunk,
current_pos,
&pk_indices,
&pk_order,
last_binlog_offset.clone(),
)?,
&self.output_indices,
));
}
} else {
// If no current_pos, means we did not process any snapshot yet.
// we can just ignore the upstream buffer chunk in that case.
upstream_chunk_buffer.clear();
}
// Update last seen binlog offset
if consumed_binlog_offset.is_some() {
last_binlog_offset.clone_from(&consumed_binlog_offset);
}
Self::report_metrics(
&self.metrics,
cur_barrier_snapshot_processed_rows,
cur_barrier_upstream_processed_rows,
);
// update and persist current backfill progress
state_impl
.mutate_state(
current_pk_pos.clone(),
last_binlog_offset.clone(),
total_snapshot_row_count,
false,
)
.await?;
state_impl.commit_state(pending_barrier.epoch).await?;
yield Message::Barrier(pending_barrier);
}
} else if self.options.disable_backfill {
// If backfill is disabled, we just mark the backfill as finished
tracing::info!(
table_id,
upstream_table_name,
"CdcBackfill has been disabled"
);
state_impl
.mutate_state(
current_pk_pos.clone(),
last_binlog_offset.clone(),
total_snapshot_row_count,
true,
)
.await?;
}
// drop reader to release db connection
drop(upstream_table_reader);
tracing::info!(
table_id,
upstream_table_name,
"CdcBackfill has already finished and will forward messages directly to the downstream"
);
// Wait for first barrier to come after backfill is finished.
// So we can update our progress + persist the status.
while let Some(Ok(msg)) = upstream.next().await {
if let Some(msg) = mapping_message(msg, &self.output_indices) {
// If not finished then we need to update state, otherwise no need.
if let Message::Barrier(barrier) = &msg {
// finalized the backfill state
// TODO: unify `mutate_state` and `commit_state` into one method
state_impl
.mutate_state(
current_pk_pos.clone(),
last_binlog_offset.clone(),
total_snapshot_row_count,
true,
)
.await?;
state_impl.commit_state(barrier.epoch).await?;
// mark progress as finished
if let Some(progress) = self.progress.as_mut() {
progress.finish(barrier.epoch, total_snapshot_row_count);
}
yield msg;
// break after the state have been saved
break;
}
yield msg;
}
}
// After backfill progress finished
// we can forward messages directly to the downstream,
// as backfill is finished.
#[for_await]
for msg in upstream {
// upstream offsets will be removed from the message before forwarding to
// downstream
if let Some(msg) = mapping_message(msg?, &self.output_indices) {
if let Message::Barrier(barrier) = &msg {
// commit state just to bump the epoch of state table
state_impl.commit_state(barrier.epoch).await?;
}
yield msg;
}
}
}
}
#[try_stream(ok = Message, error = StreamExecutorError)]
pub async fn transform_upstream(upstream: BoxedMessageStream, output_columns: &[ColumnDesc]) {
let props = SpecificParserConfig {
encoding_config: EncodingProperties::Json(JsonProperties {
use_schema_registry: false,
timestamptz_handling: None,
}),
// the cdc message is generated internally so the key must exist.
protocol_config: ProtocolProperties::Debezium(DebeziumProps::default()),
};
// convert to source column desc to feed into parser
let columns_with_meta = output_columns
.iter()
.map(SourceColumnDesc::from)
.collect_vec();
let mut parser = DebeziumParser::new(
props,
columns_with_meta.clone(),
Arc::new(SourceContext::dummy()),
)
.await
.map_err(StreamExecutorError::connector_error)?;
pin_mut!(upstream);
#[for_await]
for msg in upstream {
let mut msg = msg?;
if let Message::Chunk(chunk) = &mut msg {
let parsed_chunk = parse_debezium_chunk(&mut parser, chunk).await?;
let _ = std::mem::replace(chunk, parsed_chunk);
}
yield msg;
}
}
async fn parse_debezium_chunk(
parser: &mut DebeziumParser,
chunk: &StreamChunk,
) -> StreamExecutorResult<StreamChunk> {
// here we transform the input chunk in (payload varchar, _rw_offset varchar, _rw_table_name varchar) schema
// to chunk with downstream table schema `info.schema` of MergeNode contains the schema of the
// table job with `_rw_offset` in the end
// see `gen_create_table_plan_for_cdc_source` for details
let mut builder =
SourceStreamChunkBuilder::with_capacity(parser.columns().to_vec(), chunk.capacity());
// The schema of input chunk (payload varchar, _rw_offset varchar, _rw_table_name varchar, _row_id)
// We should use the debezium parser to parse the first column,
// then chain the parsed row with `_rw_offset` row to get a new row.
let payloads = chunk.data_chunk().project(vec![0].as_slice());
let offset_columns = chunk.data_chunk().project(vec![1].as_slice());
// TODO: preserve the transaction semantics
for payload in payloads.rows() {
let ScalarRefImpl::Jsonb(jsonb_ref) = payload.datum_at(0).expect("payload must exist")
else {
unreachable!("payload must be jsonb");
};
parser
.parse_inner(
None,
Some(jsonb_ref.to_string().as_bytes().to_vec()),
builder.row_writer(),
)
.await
.unwrap();
}
let parsed_chunk = builder.finish();
let (data_chunk, ops) = parsed_chunk.into_parts();
// concat the rows in the parsed chunk with the _rw_offset column, we should also retain the Op column
let mut new_rows = Vec::with_capacity(chunk.capacity());
let offset_columns = offset_columns.compact();
for (data_row, offset_row) in data_chunk
.rows_with_holes()
.zip_eq_fast(offset_columns.rows_with_holes())
{
let combined = data_row.chain(offset_row);
new_rows.push(combined);
}
let data_types = parser
.columns()
.iter()
.map(|col| col.data_type.clone())
.chain(std::iter::once(DataType::Varchar)) // _rw_offset column
.collect_vec();
Ok(StreamChunk::from_parts(
ops,
DataChunk::from_rows(new_rows.as_slice(), data_types.as_slice()),
))
}
impl<S: StateStore> Execute for CdcBackfillExecutor<S> {
fn execute(self: Box<Self>) -> BoxedMessageStream {
self.execute_inner().boxed()
}
}
#[cfg(test)]
mod tests {
use std::str::FromStr;
use futures::{pin_mut, StreamExt};
use risingwave_common::array::{DataChunk, Op, StreamChunk};
use risingwave_common::catalog::{ColumnDesc, ColumnId, Field, Schema};
use risingwave_common::types::{DataType, Datum, JsonbVal};
use risingwave_common::util::iter_util::ZipEqFast;
use crate::executor::backfill::cdc::cdc_backfill::transform_upstream;
use crate::executor::test_utils::MockSource;
#[tokio::test]
async fn test_transform_upstream_chunk() {
let schema = Schema::new(vec![
Field::unnamed(DataType::Jsonb), // debezium json payload
Field::unnamed(DataType::Varchar), // _rw_offset
Field::unnamed(DataType::Varchar), // _rw_table_name
]);
let pk_indices = vec![1];
let (mut tx, source) = MockSource::channel();
let source = source.into_executor(schema.clone(), pk_indices.clone());
// let payload = r#"{"before": null,"after":{"O_ORDERKEY": 5, "O_CUSTKEY": 44485, "O_ORDERSTATUS": "F", "O_TOTALPRICE": "144659.20", "O_ORDERDATE": "1994-07-30" },"source":{"version": "1.9.7.Final", "connector": "mysql", "name": "RW_CDC_1002", "ts_ms": 1695277757000, "snapshot": "last", "db": "mydb", "sequence": null, "table": "orders_new", "server_id": 0, "gtid": null, "file": "binlog.000008", "pos": 3693, "row": 0, "thread": null, "query": null},"op":"r","ts_ms":1695277757017,"transaction":null}"#.to_string();
let payload = r#"{ "payload": { "before": null, "after": { "O_ORDERKEY": 5, "O_CUSTKEY": 44485, "O_ORDERSTATUS": "F", "O_TOTALPRICE": "144659.20", "O_ORDERDATE": "1994-07-30" }, "source": { "version": "1.9.7.Final", "connector": "mysql", "name": "RW_CDC_1002", "ts_ms": 1695277757000, "snapshot": "last", "db": "mydb", "sequence": null, "table": "orders_new", "server_id": 0, "gtid": null, "file": "binlog.000008", "pos": 3693, "row": 0, "thread": null, "query": null }, "op": "r", "ts_ms": 1695277757017, "transaction": null } }"#;
let datums: Vec<Datum> = vec![
Some(JsonbVal::from_str(payload).unwrap().into()),
Some("file: 1.binlog, pos: 100".to_string().into()),
Some("mydb.orders".to_string().into()),
];
println!("datums: {:?}", datums[1]);
let mut builders = schema.create_array_builders(8);
for (builder, datum) in builders.iter_mut().zip_eq_fast(datums.iter()) {
builder.append(datum.clone());
}
let columns = builders
.into_iter()
.map(|builder| builder.finish().into())
.collect();
// one row chunk
let chunk = StreamChunk::from_parts(vec![Op::Insert], DataChunk::new(columns, 1));
tx.push_chunk(chunk);
let upstream = Box::new(source).execute();
// schema to the debezium parser
let columns = vec![
ColumnDesc::named("O_ORDERKEY", ColumnId::new(1), DataType::Int64),
ColumnDesc::named("O_CUSTKEY", ColumnId::new(2), DataType::Int64),
ColumnDesc::named("O_ORDERSTATUS", ColumnId::new(3), DataType::Varchar),
ColumnDesc::named("O_TOTALPRICE", ColumnId::new(4), DataType::Decimal),
ColumnDesc::named("O_ORDERDATE", ColumnId::new(5), DataType::Date),
ColumnDesc::named("commit_ts", ColumnId::new(6), DataType::Timestamptz),
];
let parsed_stream = transform_upstream(upstream, &columns);
pin_mut!(parsed_stream);
// the output chunk must contain the offset column
if let Some(message) = parsed_stream.next().await {
println!("chunk: {:#?}", message.unwrap());
}
}
}