named collections を使用して ClickHouse を Kafka と統合する

<access_management>1</access_management>
<named_collection_control>1</named_collection_control>
<show_named_collections_secrets>1</show_named_collections_secrets>

<!-- Kafkaインテグレーション用の名前付きコレクション -->
<named_collections>
    <cluster_1>
        <!-- ClickHouse Kafkaエンジンパラメータ -->
        <kafka_broker_list>c1-kafka-1:9094,c1-kafka-2:9094,c1-kafka-3:9094</kafka_broker_list>
        <kafka_topic_list>cluster_1_clickhouse_topic</kafka_topic_list>
        <kafka_group_name>cluster_1_clickhouse_consumer</kafka_group_name>
        <kafka_format>JSONEachRow</kafka_format>
        <kafka_commit_every_batch>0</kafka_commit_every_batch>
        <kafka_num_consumers>1</kafka_num_consumers>
        <kafka_thread_per_consumer>1</kafka_thread_per_consumer>

        <!-- Kafka拡張設定 -->
        <kafka>
            <security_protocol>SASL_SSL</security_protocol>
            <enable_ssl_certificate_verification>false</enable_ssl_certificate_verification>
            <sasl_mechanism>PLAIN</sasl_mechanism>
            <sasl_username>kafka-client</sasl_username>
            <sasl_password>kafkapassword1</sasl_password>
            <debug>all</debug>
            <auto_offset_reset>latest</auto_offset_reset>
        </kafka>
    </cluster_1>

    <cluster_2>
        <!-- ClickHouse Kafkaエンジンパラメータ -->
        <kafka_broker_list>c2-kafka-1:29094,c2-kafka-2:29094,c2-kafka-3:29094</kafka_broker_list>
        <kafka_topic_list>cluster_2_clickhouse_topic</kafka_topic_list>
        <kafka_group_name>cluster_2_clickhouse_consumer</kafka_group_name>
        <kafka_format>JSONEachRow</kafka_format>
        <kafka_commit_every_batch>0</kafka_commit_every_batch>
        <kafka_num_consumers>1</kafka_num_consumers>
        <kafka_thread_per_consumer>1</kafka_thread_per_consumer>

        <!-- Kafka拡張設定 -->
        <kafka>
            <security_protocol>SASL_SSL</security_protocol>
            <enable_ssl_certificate_verification>false</enable_ssl_certificate_verification>
            <sasl_mechanism>PLAIN</sasl_mechanism>
            <sasl_username>kafka-client</sasl_username>
            <sasl_password>kafkapassword2</sasl_password>
            <debug>all</debug>
            <auto_offset_reset>latest</auto_offset_reset>
        </kafka>
    </cluster_2>
</named_collections>

CREATE DATABASE kafka_testing ON CLUSTER LAB_CLICKHOUSE_CLUSTER;

CREATE TABLE kafka_testing.first_kafka_table ON CLUSTER LAB_CLICKHOUSE_CLUSTER
(
    `id` UInt32,
    `first_name` String,
    `last_name` String
)
ENGINE = Kafka(cluster_1);

CREATE TABLE kafka_testing.second_kafka_table ON CLUSTER STAGE_CLICKHOUSE_CLUSTER
(
    `id` UInt32,
    `first_name` String,
    `last_name` String
)
ENGINE = Kafka(cluster_2);

CREATE TABLE kafka_testing.first_replicated_table ON CLUSTER STAGE_CLICKHOUSE_CLUSTER
(
    `id` UInt32,
    `first_name` String,
    `last_name` String
) ENGINE = ReplicatedMergeTree()
ORDER BY id;

CREATE TABLE kafka_testing.second_replicated_table ON CLUSTER STAGE_CLICKHOUSE_CLUSTER
(
    `id` UInt32,
    `first_name` String,
    `last_name` String
) ENGINE = ReplicatedMergeTree()
ORDER BY id;

CREATE MATERIALIZED VIEW kafka_testing.cluster_1_mv ON CLUSTER STAGE_CLICKHOUSE_CLUSTER TO first_replicated_table AS
SELECT 
    id,
    first_name,
    last_name
FROM first_kafka_table;

CREATE MATERIALIZED VIEW kafka_testing.cluster_2_mv ON CLUSTER STAGE_CLICKHOUSE_CLUSTER TO second_replicated_table AS
SELECT 
    id,
    first_name,
    last_name
FROM second_kafka_table;

SELECT * FROM first_replicated_table LIMIT 10;

SELECT * FROM second_replicated_table LIMIT 10;

┌─id─┬─first_name─┬─last_name─┐
│  0 │ FirstName0 │ LastName0 │
│  1 │ FirstName1 │ LastName1 │
│  2 │ FirstName2 │ LastName2 │
└────┴────────────┴───────────┘