ClickHouse/tests/integration/test_structured_logging_json/configs/config_json.xml

<clickhouse>
    <logger>
        <!-- Structured log formatting:
        You can specify log format(for now, JSON only). In that case, the console log will be printed
        in specified format like JSON.
        For example, as below:
        {"date_time":"1650918987.180175","thread_name":"#1","thread_id":"254545","level":"Trace","query_id":"","logger_name":"BaseDaemon","message":"Received signal 2","source_file":"../base/daemon/BaseDaemon.cpp; virtual void SignalListener::run()","source_line":"192"}
        To enable JSON logging support, just uncomment <formatting> tag below.
        -->
        <formatting>
            <type>json</type>
            <names>
                <date_time>DATE_TIME</date_time>
                <thread_name>THREAD_NAME</thread_name>
                <thread_id>THREAD_ID</thread_id>
                <level>LEVEL</level>
                <query_id>QUERY_ID</query_id>
                <logger_name>LOGGER_NAME</logger_name>
                <message>MESSAGE</message>
                <source_file>SOURCE_FILE</source_file>
                <source_line>SOURCE_LINE</source_line>
            </names>
        </formatting>
    </logger>

</clickhouse>