feat: Add a debug table for clickhouse_events_json (#23377)

Co-authored-by: github-actions <41898282+github-actions[bot]@users.noreply.github.com>
Co-authored-by: Juraj Majerik <[email protected]>

posthog/clickhouse/migrations/0067_event_kafka_debug_table.py

@@ -0,0 +1,20 @@
+from posthog.clickhouse.client.migration_tools import run_sql_with_exceptions
+from posthog.kafka_client.topics import KAFKA_EVENTS_JSON
+from posthog.models.kafka_debug.sql import (
+    KafkaDebugKafkaTable,
+    KafkaDebugTable,
+    KafkaDebugMaterializedView,
+)
+from posthog.settings.data_stores import KAFKA_HOSTS
+
+
+debug_table = KafkaDebugTable(topic=KAFKA_EVENTS_JSON)
+kafka_table = KafkaDebugKafkaTable(brokers=KAFKA_HOSTS, topic=KAFKA_EVENTS_JSON)
+materialized_view = KafkaDebugMaterializedView(to_table=debug_table, from_table=kafka_table)
+
+
+operations = [
+    run_sql_with_exceptions(debug_table.get_create_table_sql()),
+    run_sql_with_exceptions(kafka_table.get_create_table_sql()),
+    run_sql_with_exceptions(materialized_view.get_create_view_sql()),
+]

posthog/models/kafka_debug/sql.py

@@ -0,0 +1,86 @@
+from dataclasses import dataclass
+from posthog.clickhouse.kafka_engine import kafka_engine
+from posthog.clickhouse.table_engines import MergeTreeEngine
+from posthog.settings import CLICKHOUSE_CLUSTER, CLICKHOUSE_DATABASE
+
+
+@dataclass
+class KafkaDebugKafkaTable:
+    brokers: list[str]
+    topic: str
+    consumer_group: str = "debug"
+
+    @property
+    def table_name(self) -> str:
+        return f"kafka_{self.topic}_debug"
+
+    def get_create_table_sql(self) -> str:
+        return f"""
+      CREATE TABLE IF NOT EXISTS `{CLICKHOUSE_DATABASE}`.{self.table_name} ON CLUSTER '{CLICKHOUSE_CLUSTER}'
+      (
+        payload String
+      )
+      ENGINE={kafka_engine(kafka_host=",".join(self.brokers), topic=self.topic, group=self.consumer_group)}
+      SETTINGS input_format_values_interpret_expressions=0, kafka_handle_error_mode='stream'
+    """
+
+    def get_drop_table_sql(self) -> str:
+        return f"""
+      DROP TABLE IF EXISTS `{CLICKHOUSE_DATABASE}`.{self.table_name} ON CLUSTER '{CLICKHOUSE_CLUSTER}'
+    """
+
+
+@dataclass
+class KafkaDebugTable:
+    topic: str
+
+    @property
+    def table_name(self) -> str:
+        return f"{self.topic}_debug"
+
+    def get_create_table_sql(self) -> str:
+        engine = MergeTreeEngine(self.table_name)
+        return f"""
+      CREATE TABLE IF NOT EXISTS `{CLICKHOUSE_DATABASE}`.{self.table_name} ON CLUSTER '{CLICKHOUSE_CLUSTER}' (
+        payload String,
+        _timestamp DateTime,
+        _timestamp_ms Nullable(DateTime64(3)),
+        _partition UInt64,
+        _offset UInt64,
+        _error String,
+        _raw_message String
+      )
+      ENGINE = {engine}
+      PARTITION BY toStartOfHour(_timestamp)
+      ORDER BY (_partition, _offset)
+      TTL _timestamp + INTERVAL 14 DAY
+    """
+
+
+@dataclass
+class KafkaDebugMaterializedView:
+    to_table: KafkaDebugTable
+    from_table: KafkaDebugKafkaTable
+
+    @property
+    def view_name(self) -> str:
+        return f"{self.to_table.table_name}_mv"
+
+    def get_create_view_sql(self) -> str:
+        return f"""
+      CREATE MATERIALIZED VIEW IF NOT EXISTS `{CLICKHOUSE_DATABASE}`.{self.view_name} ON CLUSTER '{CLICKHOUSE_CLUSTER}' TO {self.to_table.table_name}
+      AS SELECT
+        payload,
+        _timestamp,
+        _timestamp_ms,
+        _partition,
+        _offset,
+        _error,
+        _raw_message
+      FROM `{CLICKHOUSE_DATABASE}`.{self.from_table.table_name}
+    """
+
+    def get_drop_view_sql(self) -> str:
+        return f"""
+      DROP TABLE IF EXISTS `{CLICKHOUSE_DATABASE}`.{self.view_name} ON CLUSTER '{CLICKHOUSE_CLUSTER}' SYNC
+    """