Merge pull request ClickHouse#86493 from ClickHouse/backport/25.8/86331

clickhouse-gh[bot] · web-flow · commit f54ab70aeb76 · 2025-09-01T18:36:00.000+01:00
Backport ClickHouse#86331 to 25.8: Add ability to enable JSON logging only for specific channel (i.e. console)
diff --git a/docs/en/operations/server-configuration-parameters/_server_settings_outside_source.md b/docs/en/operations/server-configuration-parameters/_server_settings_outside_source.md
@@ -969,6 +969,8 @@ To enable JSON logging support, use the following snippet:
 <logger>
     <formatting>
         <type>json</type>
+        <!-- Can be configured on a per-channel basis (log, errorlog, console, syslog), or globally for all channels (then just omit it). -->
+        <!-- <channel></channel> -->
         <names>
             <date_time>date_time</date_time>
             <thread_name>thread_name</thread_name>
diff --git a/programs/server/config.xml b/programs/server/config.xml
@@ -72,10 +72,12 @@
           </logger>
         </levels>
         -->
+
         <!-- 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:
+
+        You can specify log format(for now, JSON only).
+        It can be done either on a per-channel (log, errorlog, console, syslog) level (set `channel`, i.e. `<channel>console</channel>') or for all channels (omit `channel`).
+        The log will be printed in specified format like JSON, example:
 
         {"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"}
         {"date_time_utc":"2024-11-06T09:06:09Z","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"}
@@ -91,8 +93,10 @@
         However, if you comment out all the tags under <names>, the program will print default values for as
         below.
         -->
-        <!-- <formatting>
+        <!--
+        <formatting>
             <type>json</type>
+            <channel></channel>
             <names>
                 <date_time>date_time</date_time>
                 <date_time_utc>date_time_utc</date_time_utc>
@@ -105,7 +109,8 @@
                 <source_file>source_file</source_file>
                 <source_line>source_line</source_line>
             </names>
-        </formatting> -->
+        </formatting>
+        -->
     </logger>
 
     <url_scheme_mappers>
diff --git a/src/Daemon/BaseDaemon.cpp b/src/Daemon/BaseDaemon.cpp
@@ -621,11 +621,7 @@ void BaseDaemon::setupWatchdog()
         /// If streaming compression of logs is used then we write watchdog logs to cerr
         if (config().getRawString("logger.stream_compress", "false") == "true")
         {
-            Poco::AutoPtr<OwnPatternFormatter> pf;
-            if (config().getString("logger.formatting.type", "") == "json")
-                pf = new OwnJSONPatternFormatter(config());
-            else
-                pf = new OwnPatternFormatter;
+            Poco::AutoPtr<OwnPatternFormatter> pf = getFormatForChannel(config(), "console");
             Poco::AutoPtr<OwnFormattingChannel> log = new OwnFormattingChannel(pf, new Poco::ConsoleChannel(std::cerr));
             logger().setChannel(log);
         }
diff --git a/src/Loggers/Loggers.cpp b/src/Loggers/Loggers.cpp
@@ -67,6 +67,37 @@ static std::string renderFileNameTemplate(time_t now, const std::string & file_p
     return path.replace_filename(ss.str());
 }
 
+Poco::AutoPtr<OwnPatternFormatter> getFormatForChannel(Poco::Util::AbstractConfiguration & config, const std::string & channel, bool color)
+{
+    Poco::Util::AbstractConfiguration::Keys keys;
+    config.keys("logger", keys);
+
+    std::string config_prefix_for_channel;
+    std::string config_prefix_global;
+    for (const auto & key : keys)
+    {
+        if (key != "formatting" && !key.starts_with("formatting["))
+            continue;
+
+        if (config.getString(fmt::format("logger.{}.channel", key), "") == channel)
+        {
+            config_prefix_for_channel = "logger." + key;
+            break;
+        }
+        if (config.getString(fmt::format("logger.{}.channel", key), "").empty())
+        {
+            config_prefix_global = "logger." + key;
+            break;
+        }
+    }
+
+    const auto & config_prefix = config_prefix_for_channel.empty() ? config_prefix_global : config_prefix_for_channel;
+    if (config.getString(config_prefix + ".type", "") == "json")
+        return new OwnJSONPatternFormatter(config, config_prefix);
+    else
+        return new OwnPatternFormatter(color);
+}
+
 /// NOLINTBEGIN(readability-static-accessed-through-instance)
 
 void Loggers::buildLoggers(Poco::Util::AbstractConfiguration & config, Poco::Logger & logger /*_root*/, const std::string & cmd_name)
@@ -124,13 +155,7 @@ void Loggers::buildLoggers(Poco::Util::AbstractConfiguration & config, Poco::Log
         log_file->setProperty(Poco::FileChannel::PROP_ROTATEONOPEN, config.getRawString("logger.rotateOnOpen", "false"));
         log_file->open();
 
-        Poco::AutoPtr<OwnPatternFormatter> pf;
-
-        if (config.getString("logger.formatting.type", "") == "json")
-            pf = new OwnJSONPatternFormatter(config);
-        else
-            pf = new OwnPatternFormatter;
-
+        Poco::AutoPtr<OwnPatternFormatter> pf = getFormatForChannel(config, "log");
         auto log = std::make_shared<DB::OwnFormattingChannel>(pf, log_file);
         split->addChannel(
             log, "FileLog", log_level, ProfileEvents::AsyncLoggingFileLogTotalMessages, ProfileEvents::AsyncLoggingFileLogDroppedMessages);
@@ -163,13 +188,7 @@ void Loggers::buildLoggers(Poco::Util::AbstractConfiguration & config, Poco::Log
         error_log_file->setProperty(Poco::FileChannel::PROP_FLUSH, config.getRawString("logger.flush", "true"));
         error_log_file->setProperty(Poco::FileChannel::PROP_ROTATEONOPEN, config.getRawString("logger.rotateOnOpen", "false"));
 
-        Poco::AutoPtr<OwnPatternFormatter> pf;
-
-        if (config.getString("logger.formatting.type", "") == "json")
-            pf = new OwnJSONPatternFormatter(config);
-        else
-            pf = new OwnPatternFormatter;
-
+        Poco::AutoPtr<OwnPatternFormatter> pf = getFormatForChannel(config, "errorlog");
         auto errorlog = std::make_shared<DB::OwnFormattingChannel>(pf, error_log_file);
         errorlog->open();
         split->addChannel(
@@ -207,13 +226,7 @@ void Loggers::buildLoggers(Poco::Util::AbstractConfiguration & config, Poco::Log
         }
         syslog_channel->open();
 
-        Poco::AutoPtr<OwnPatternFormatter> pf;
-
-        if (config.getString("logger.formatting.type", "") == "json")
-            pf = new OwnJSONPatternFormatter(config);
-        else
-            pf = new OwnPatternFormatter;
-
+        Poco::AutoPtr<OwnPatternFormatter> pf = getFormatForChannel(config, "syslog");
         auto log = std::make_shared<DB::OwnFormattingChannel>(pf, syslog_channel);
         split->addChannel(
             log, "Syslog", syslog_level, ProfileEvents::AsyncLoggingSyslogTotalMessages, ProfileEvents::AsyncLoggingSyslogDroppedMessages);
@@ -231,11 +244,7 @@ void Loggers::buildLoggers(Poco::Util::AbstractConfiguration & config, Poco::Log
         auto console_log_level = Poco::Logger::parseLevel(console_log_level_string);
         max_log_level = std::max(console_log_level, max_log_level);
 
-        Poco::AutoPtr<OwnPatternFormatter> pf;
-        if (config.getString("logger.formatting.type", "") == "json")
-            pf = new OwnJSONPatternFormatter(config);
-        else
-            pf = new OwnPatternFormatter(color_enabled);
+        Poco::AutoPtr<OwnPatternFormatter> pf = getFormatForChannel(config, "console", color_enabled);
         auto log = std::make_shared<DB::OwnFormattingChannel>(pf, new Poco::ConsoleChannel);
         split->addChannel(
             log,
diff --git a/src/Loggers/Loggers.h b/src/Loggers/Loggers.h
@@ -50,3 +50,6 @@ class Loggers
 
     Poco::AutoPtr<DB::OwnSplitChannelBase> split;
 };
+
+class OwnPatternFormatter;
+Poco::AutoPtr<OwnPatternFormatter> getFormatForChannel(Poco::Util::AbstractConfiguration & config, const std::string & channel, bool color = false);
diff --git a/src/Loggers/OwnJSONPatternFormatter.cpp b/src/Loggers/OwnJSONPatternFormatter.cpp
@@ -1,6 +1,5 @@
 #include <Loggers/OwnJSONPatternFormatter.h>
 
-#include <functional>
 #include <IO/WriteBufferFromString.h>
 #include <IO/WriteHelpers.h>
 #include <Interpreters/InternalTextLogsQueue.h>
@@ -11,37 +10,37 @@
 #include <Common/DateLUTImpl.h>
 
 
-OwnJSONPatternFormatter::OwnJSONPatternFormatter(Poco::Util::AbstractConfiguration & config)
+OwnJSONPatternFormatter::OwnJSONPatternFormatter(Poco::Util::AbstractConfiguration & config, const std::string & config_prefix)
 {
-    if (config.has("logger.formatting.names.date_time"))
-        date_time = config.getString("logger.formatting.names.date_time", "");
+    if (config.has(config_prefix + ".names.date_time"))
+        date_time = config.getString(config_prefix + ".names.date_time", "");
 
-    if (config.has("logger.formatting.names.date_time_utc"))
-        date_time_utc= config.getString("logger.formatting.names.date_time_utc", "");
+    if (config.has(config_prefix + ".names.date_time_utc"))
+        date_time_utc= config.getString(config_prefix + ".names.date_time_utc", "");
 
-    if (config.has("logger.formatting.names.thread_name"))
-        thread_name = config.getString("logger.formatting.names.thread_name", "");
+    if (config.has(config_prefix + ".names.thread_name"))
+        thread_name = config.getString(config_prefix + ".names.thread_name", "");
 
-    if (config.has("logger.formatting.names.thread_id"))
-        thread_id = config.getString("logger.formatting.names.thread_id", "");
+    if (config.has(config_prefix + ".names.thread_id"))
+        thread_id = config.getString(config_prefix + ".names.thread_id", "");
 
-    if (config.has("logger.formatting.names.level"))
-        level = config.getString("logger.formatting.names.level", "");
+    if (config.has(config_prefix + ".names.level"))
+        level = config.getString(config_prefix + ".names.level", "");
 
-    if (config.has("logger.formatting.names.query_id"))
-        query_id = config.getString("logger.formatting.names.query_id", "");
+    if (config.has(config_prefix + ".names.query_id"))
+        query_id = config.getString(config_prefix + ".names.query_id", "");
 
-    if (config.has("logger.formatting.names.logger_name"))
-        logger_name = config.getString("logger.formatting.names.logger_name", "");
+    if (config.has(config_prefix + ".names.logger_name"))
+        logger_name = config.getString(config_prefix + ".names.logger_name", "");
 
-    if (config.has("logger.formatting.names.message"))
-        message = config.getString("logger.formatting.names.message", "");
+    if (config.has(config_prefix + ".names.message"))
+        message = config.getString(config_prefix + ".names.message", "");
 
-    if (config.has("logger.formatting.names.source_file"))
-        source_file = config.getString("logger.formatting.names.source_file", "");
+    if (config.has(config_prefix + ".names.source_file"))
+        source_file = config.getString(config_prefix + ".names.source_file", "");
 
-    if (config.has("logger.formatting.names.source_line"))
-        source_line = config.getString("logger.formatting.names.source_line", "");
+    if (config.has(config_prefix + ".names.source_line"))
+        source_line = config.getString(config_prefix + ".names.source_line", "");
 
     if (date_time.empty() && thread_name.empty() && thread_id.empty() && level.empty() && query_id.empty()
         && logger_name.empty() && message.empty() && source_file.empty() && source_line.empty())
diff --git a/src/Loggers/OwnJSONPatternFormatter.h b/src/Loggers/OwnJSONPatternFormatter.h
@@ -26,7 +26,7 @@ class Loggers;
 class OwnJSONPatternFormatter : public OwnPatternFormatter
 {
 public:
-    explicit OwnJSONPatternFormatter(Poco::Util::AbstractConfiguration & config);
+    explicit OwnJSONPatternFormatter(Poco::Util::AbstractConfiguration & config, const std::string & config_prefix);
 
     void format(const Poco::Message & msg, std::string & text) override;
     void formatExtended(const DB::ExtendedLogMessage & msg_ext, std::string & text) const override;
diff --git a/tests/integration/test_structured_logging_json/configs/config_json_logging_per_channel.xml b/tests/integration/test_structured_logging_json/configs/config_json_logging_per_channel.xml
@@ -0,0 +1,21 @@
+<?xml version="1.0"?>
+<clickhouse>
+    <logger>
+        <formatting>
+            <type>json</type>
+            <channel>errorlog</channel>
+            <names>
+                <date_time>DATE_TIME</date_time>
+                <date_time_utc>DATE_TIME_UTC</date_time_utc>
+                <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>
diff --git a/tests/integration/test_structured_logging_json/test.py b/tests/integration/test_structured_logging_json/test.py
@@ -17,6 +17,10 @@
     "node_no_keys", main_configs=["configs/config_no_keys_json.xml"]
 )
 
+node_json_logging_per_channel = cluster.add_instance(
+    "node_json_logging_per_channel", main_configs=["configs/config_json_logging_per_channel.xml"]
+)
+
 
 @pytest.fixture(scope="module")
 def start_cluster():
@@ -147,3 +151,12 @@ def test_structured_logging_json_format(start_cluster):
         == True
     )
     assert validate_everything(config_no_keys, node_no_keys, "config_no_keys") == True
+
+def test_structured_logging_per_channel(start_cluster):
+    logs = node_json_logging_per_channel.grep_in_log("").split("\n")
+    assert len(logs) > 0
+    assert not validate_logs(logs)
+
+    error_logs = node_json_logging_per_channel.grep_in_log("", filename="clickhouse-server.err.log").strip().split("\n")
+    assert len(error_logs) > 0
+    assert validate_logs(error_logs)

Original file line number	Diff line number	Diff line change
`@@ -621,11 +621,7 @@ void BaseDaemon::setupWatchdog()`
`621`	`621`	`/// If streaming compression of logs is used then we write watchdog logs to cerr`
`622`	`622`	`if (config().getRawString("logger.stream_compress", "false") == "true")`
`623`	`623`	`{`
`624`		`- Poco::AutoPtr<OwnPatternFormatter> pf;`
`625`		`- if (config().getString("logger.formatting.type", "") == "json")`
`626`		`- pf = new OwnJSONPatternFormatter(config());`
`627`		`- else`
`628`		`- pf = new OwnPatternFormatter;`
	`624`	`+ Poco::AutoPtr<OwnPatternFormatter> pf = getFormatForChannel(config(), "console");`
`629`	`625`	`Poco::AutoPtr<OwnFormattingChannel> log = new OwnFormattingChannel(pf, new Poco::ConsoleChannel(std::cerr));`
`630`	`626`	`logger().setChannel(log);`
`631`	`627`	`}`
Original file line number	Diff line number	Diff line change
`@@ -26,7 +26,7 @@ class Loggers;`
`26`	`26`	`class OwnJSONPatternFormatter : public OwnPatternFormatter`
`27`	`27`	`{`
`28`	`28`	`public:`
`29`		`- explicit OwnJSONPatternFormatter(Poco::Util::AbstractConfiguration & config);`
	`29`	`+ explicit OwnJSONPatternFormatter(Poco::Util::AbstractConfiguration & config, const std::string & config_prefix);`
`30`	`30`
`31`	`31`	`void format(const Poco::Message & msg, std::string & text) override;`
`32`	`32`	`void formatExtended(const DB::ExtendedLogMessage & msg_ext, std::string & text) const override;`