|
| 1 | +import asyncio |
| 2 | +import argparse |
| 3 | +import logging |
| 4 | +import ydb |
| 5 | + |
| 6 | + |
| 7 | +async def connect(endpoint: str, database: str) -> ydb.aio.Driver: |
| 8 | + config = ydb.DriverConfig(endpoint=endpoint, database=database) |
| 9 | + config.credentials = ydb.credentials_from_env_variables() |
| 10 | + driver = ydb.aio.Driver(config) |
| 11 | + await driver.wait(5, fail_fast=True) |
| 12 | + return driver |
| 13 | + |
| 14 | + |
| 15 | +async def create_topic(driver: ydb.aio.Driver, topic: str, consumer: str): |
| 16 | + try: |
| 17 | + await driver.topic_client.drop_topic(topic) |
| 18 | + except ydb.SchemeError: |
| 19 | + pass |
| 20 | + |
| 21 | + await driver.topic_client.create_topic(topic, consumers=[consumer]) |
| 22 | + |
| 23 | + |
| 24 | +async def write_with_tx_example(driver: ydb.aio.Driver, topic: str, message_count: int = 10): |
| 25 | + async with ydb.aio.QuerySessionPool(driver) as session_pool: |
| 26 | + |
| 27 | + async def callee(tx: ydb.aio.QueryTxContext): |
| 28 | + tx_writer: ydb.TopicTxWriterAsyncIO = driver.topic_client.tx_writer(tx, topic) |
| 29 | + |
| 30 | + for i in range(message_count): |
| 31 | + async with await tx.execute(query=f"select {i} as res;") as result_stream: |
| 32 | + async for result_set in result_stream: |
| 33 | + message = str(result_set.rows[0]["res"]) |
| 34 | + await tx_writer.write(ydb.TopicWriterMessage(message)) |
| 35 | + print(f"Message {result_set.rows[0]['res']} was written with tx.") |
| 36 | + |
| 37 | + await session_pool.retry_tx_async(callee) |
| 38 | + |
| 39 | + |
| 40 | +async def read_with_tx_example(driver: ydb.aio.Driver, topic: str, consumer: str, message_count: int = 10): |
| 41 | + async with driver.topic_client.reader(topic, consumer) as reader: |
| 42 | + async with ydb.aio.QuerySessionPool(driver) as session_pool: |
| 43 | + for _ in range(message_count): |
| 44 | + |
| 45 | + async def callee(tx: ydb.aio.QueryTxContext): |
| 46 | + batch = await reader.receive_batch_with_tx(tx, max_messages=1) |
| 47 | + print(f"Message {batch.messages[0].data.decode()} was read with tx.") |
| 48 | + |
| 49 | + await session_pool.retry_tx_async(callee) |
| 50 | + |
| 51 | + |
| 52 | +async def main(): |
| 53 | + parser = argparse.ArgumentParser( |
| 54 | + formatter_class=argparse.RawDescriptionHelpFormatter, |
| 55 | + description="""YDB topic basic example.\n""", |
| 56 | + ) |
| 57 | + parser.add_argument("-d", "--database", default="/local", help="Name of the database to use") |
| 58 | + parser.add_argument("-e", "--endpoint", default="grpc://localhost:2136", help="Endpoint url to use") |
| 59 | + parser.add_argument("-p", "--path", default="test-topic", help="Topic name") |
| 60 | + parser.add_argument("-c", "--consumer", default="consumer", help="Consumer name") |
| 61 | + parser.add_argument("-v", "--verbose", default=False, action="store_true") |
| 62 | + parser.add_argument( |
| 63 | + "-s", |
| 64 | + "--skip-drop-and-create-topic", |
| 65 | + default=False, |
| 66 | + action="store_true", |
| 67 | + help="Use existed topic, skip remove it and re-create", |
| 68 | + ) |
| 69 | + |
| 70 | + args = parser.parse_args() |
| 71 | + |
| 72 | + if args.verbose: |
| 73 | + logger = logging.getLogger("topicexample") |
| 74 | + logger.setLevel(logging.DEBUG) |
| 75 | + logger.addHandler(logging.StreamHandler()) |
| 76 | + |
| 77 | + async with await connect(args.endpoint, args.database) as driver: |
| 78 | + if not args.skip_drop_and_create_topic: |
| 79 | + await create_topic(driver, args.path, args.consumer) |
| 80 | + |
| 81 | + await write_with_tx_example(driver, args.path) |
| 82 | + await read_with_tx_example(driver, args.path, args.consumer) |
| 83 | + |
| 84 | + |
| 85 | +if __name__ == "__main__": |
| 86 | + asyncio.run(main()) |
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