DynamoDB CDC: Add ctk load table interface for processing CDC events

In contrast to the Lambda-based processor implementation, this one is
a standalone one that can be used optimally in any Python environment,
managed or not.

.github/workflows/dynamodb.yml

@@ -42,8 +42,8 @@ jobs:
         os: ["ubuntu-latest"]
         # TODO: yarl, dependency of influxio, is currently not available on Python 3.12.
         #       https://github.com/aio-libs/yarl/pull/942
-        python-version: ["3.8", "3.11"]
-        localstack-version: ["3.7"]
+        python-version: ["3.9", "3.11"]
+        localstack-version: ["3.6"]
 
     env:
       OS: ${{ matrix.os }}
@@ -78,7 +78,7 @@ jobs:
         pip install "setuptools>=64" --upgrade
 
         # Install package in editable mode.
-        pip install --use-pep517 --prefer-binary --editable=.[dynamodb,test,develop]
+        pip install --use-pep517 --prefer-binary --editable=.[dynamodb,kinesis,test,develop]
 
     - name: Run linter and software tests
       run: |

CHANGES.md

@@ -7,6 +7,7 @@
 - MongoDB: Unlock processing JSON files from HTTP resource, using `https+bson://`
 - MongoDB: Optionally filter server collection using MongoDB query expression
 - MongoDB: Improve error handling wrt. bulk operations vs. usability
+- DynamoDB CDC: Add `ctk load table` interface for processing CDC events
 
 ## 2024/09/10 v0.0.22
 - MongoDB: Rename columns with leading underscores to use double leading underscores

cratedb_toolkit/api/main.py

@@ -138,9 +138,18 @@ def load_table(self, resource: InputOutputResource, target: TableAddress, transf
                 logger.error("Data loading failed or incomplete")
                 return False
 
+        elif source_url_obj.scheme.startswith("kinesis"):
+            if "+cdc" in source_url_obj.scheme:
+                from cratedb_toolkit.io.kinesis.api import kinesis_relay
+
+                return kinesis_relay(str(source_url_obj), target_url)
+            else:
+                raise NotImplementedError("Loading full data via Kinesis not implemented yet")
+
         elif source_url_obj.scheme in ["file+bson", "http+bson", "https+bson", "mongodb", "mongodb+srv"]:
             if "+cdc" in source_url_obj.scheme:
                 source_url_obj.scheme = source_url_obj.scheme.replace("+cdc", "")
+
                 from cratedb_toolkit.io.mongodb.api import mongodb_relay_cdc
 
                 return mongodb_relay_cdc(str(source_url_obj), target_url, progress=True)

cratedb_toolkit/io/kinesis/adapter.py

@@ -0,0 +1,83 @@
+import asyncio
+import typing as t
+
+import boto3
+from aiobotocore.session import AioSession
+from kinesis import Consumer, JsonProcessor, Producer
+from yarl import URL
+
+
+class KinesisAdapter:
+    def __init__(self, kinesis_url: URL):
+        self.async_session = AioSession()
+        self.async_session.set_credentials(access_key=kinesis_url.user, secret_key=kinesis_url.password)
+
+        self.session = boto3.Session(
+            aws_access_key_id=kinesis_url.user,
+            aws_secret_access_key=kinesis_url.password,
+            region_name=kinesis_url.query.get("region"),
+        )
+
+        self.endpoint_url = None
+        if kinesis_url.host and kinesis_url.host.lower() != "aws":
+            self.endpoint_url = f"http://{kinesis_url.host}:{kinesis_url.port}"
+        self.kinesis_url = kinesis_url
+        self.region_name = kinesis_url.query.get("region")
+        self.stream_name = self.kinesis_url.path.lstrip("/")
+        self.kinesis_client = self.session.client("kinesis", endpoint_url=self.endpoint_url)
+
+    def consumer_factory(self, **kwargs):
+        return Consumer(
+            stream_name=self.stream_name,
+            session=self.async_session,
+            endpoint_url=self.endpoint_url,
+            region_name=self.region_name,
+            processor=JsonProcessor(),
+            **kwargs,
+        )
+
+    def consume_forever(self, handler: t.Callable):
+        asyncio.run(self._consume_forever(handler))
+
+    def consume_once(self, handler: t.Callable):
+        asyncio.run(self._consume_once(handler))
+
+    async def _consume_forever(self, handler: t.Callable):
+        """
+        Consume items from a Kinesis stream.
+        """
+        async with self.consumer_factory(
+            # TODO: Make configurable.
+            create_stream=True,
+            iterator_type="TRIM_HORIZON",
+            sleep_time_no_records=0.2,
+        ) as consumer:
+            while True:
+                async for item in consumer:
+                    handler(item)
+
+    async def _consume_once(self, handler: t.Callable):
+        async with self.consumer_factory(
+            # TODO: Make configurable.
+            create_stream=True,
+            iterator_type="TRIM_HORIZON",
+            sleep_time_no_records=0.2,
+        ) as consumer:
+            async for item in consumer:
+                handler(item)
+
+    def produce(self, data: t.Dict[str, t.Any]):
+        asyncio.run(self._produce(data))
+
+    async def _produce(self, data: t.Dict[str, t.Any]):
+        # Put item onto queue to be flushed via `put_records()`.
+        async with Producer(
+            stream_name=self.stream_name,
+            session=self.async_session,
+            endpoint_url=self.endpoint_url,
+            region_name=self.region_name,
+            # TODO: Make configurable.
+            create_stream=True,
+            buffer_time=0.01,
+        ) as producer:
+            await producer.put(data)

cratedb_toolkit/io/kinesis/api.py

@@ -0,0 +1,6 @@
+from cratedb_toolkit.io.kinesis.relay import KinesisRelay
+
+
+def kinesis_relay(source_url, target_url):
+    ka = KinesisRelay(source_url, target_url)
+    ka.start()

cratedb_toolkit/io/kinesis/relay.py

@@ -0,0 +1,82 @@
+import base64
+import json
+import logging
+
+import sqlalchemy as sa
+from commons_codec.transform.dynamodb import DynamoDBCDCTranslator
+from tqdm import tqdm
+from tqdm.contrib.logging import logging_redirect_tqdm
+from yarl import URL
+
+from cratedb_toolkit.io.kinesis.adapter import KinesisAdapter
+from cratedb_toolkit.model import DatabaseAddress
+from cratedb_toolkit.util import DatabaseAdapter
+
+logger = logging.getLogger(__name__)
+
+
+class KinesisRelay:
+    """
+    Relay events from Kinesis into CrateDB table.
+    """
+
+    def __init__(
+        self,
+        kinesis_url: str,
+        cratedb_url: str,
+    ):
+        cratedb_address = DatabaseAddress.from_string(cratedb_url)
+        cratedb_sqlalchemy_url, cratedb_table_address = cratedb_address.decode()
+        cratedb_table = cratedb_table_address.fullname
+
+        self.kinesis_url = URL(kinesis_url)
+        self.kinesis_adapter = KinesisAdapter(self.kinesis_url)
+        self.cratedb_adapter = DatabaseAdapter(str(cratedb_sqlalchemy_url), echo=False)
+        self.cratedb_table = self.cratedb_adapter.quote_relation_name(cratedb_table)
+
+        if "dynamodb+cdc" in self.kinesis_url.scheme:
+            self.translator = DynamoDBCDCTranslator(table_name=self.cratedb_table)
+        else:
+            raise NotImplementedError(f"Data processing not implemented for {self.kinesis_url}")
+
+        self.connection: sa.Connection
+        self.progress_bar: tqdm
+
+    def start(self, once: bool = False):
+        """
+        Read events from Kinesis stream, convert to SQL statements, and submit to CrateDB.
+        """
+        logger.info(f"Source: Kinesis stream={self.kinesis_adapter.stream_name} count=unknown")
+        self.connection = self.cratedb_adapter.engine.connect()
+        if not self.cratedb_adapter.table_exists(self.cratedb_table):
+            self.connection.execute(sa.text(self.translator.sql_ddl))
+            self.connection.commit()
+        records_target = self.cratedb_adapter.count_records(self.cratedb_table)
+        logger.info(f"Target: CrateDB table={self.cratedb_table} count={records_target}")
+        # Harmonize logging and progress bar.
+        # https://github.com/tqdm/tqdm#redirecting-logging
+        self.progress_bar = tqdm()
+        with logging_redirect_tqdm():
+            if once:
+                self.kinesis_adapter.consume_once(self.process_event)
+            else:
+                self.kinesis_adapter.consume_forever(self.process_event)
+
+    def process_event(self, event):
+        try:
+            record = json.loads(base64.b64decode(event["kinesis"]["data"]).decode("utf-8"))
+            operation = self.translator.to_sql(record)
+        except Exception:
+            logger.exception("Decoding Kinesis event failed")
+            return
+        try:
+            # Process record.
+            self.connection.execute(sa.text(operation.statement), operation.parameters)
+
+            # Processing alternating CDC events requires write synchronization.
+            self.connection.execute(sa.text(f"REFRESH TABLE {self.cratedb_table}"))
+
+            self.connection.commit()
+        except sa.exc.ProgrammingError as ex:
+            logger.warning(f"Running query failed: {ex}")
+        self.progress_bar.update()