Logging: JSONFormatter

Foundation/Foundation_vs160.vcxproj

@@ -873,6 +873,7 @@
     <ClCompile Include="src\inflate.c" />
     <ClCompile Include="src\InflatingStream.cpp" />
     <ClCompile Include="src\inftrees.c" />
+    <ClCompile Include="src\JSONFormatter.cpp" />
     <ClCompile Include="src\JSONString.cpp" />
     <ClCompile Include="src\Latin1Encoding.cpp" />
     <ClCompile Include="src\Latin2Encoding.cpp" />
@@ -1637,6 +1638,7 @@
     <ClInclude Include="include\Poco\HMACEngine.h" />
     <ClInclude Include="include\Poco\InflatingStream.h" />
     <ClInclude Include="include\Poco\Instantiator.h" />
+    <ClInclude Include="include\Poco\JSONFormatter.h" />
     <ClInclude Include="include\Poco\JSONString.h" />
     <ClInclude Include="include\Poco\KeyValueArgs.h" />
     <ClInclude Include="include\Poco\Latin1Encoding.h" />

Foundation/Foundation_vs160.vcxproj.filters

@@ -940,6 +940,9 @@
     <ClCompile Include="src\utf8proc_data.c">
       <Filter>Text\Utf8Proc Source Files</Filter>
     </ClCompile>
+    <ClCompile Include="src\JSONFormatter.cpp">
+      <Filter>Logging\Source Files</Filter>
+    </ClCompile>
   </ItemGroup>
   <ItemGroup>
     <ClInclude Include="include\Poco\Any.h">
@@ -1896,6 +1899,9 @@
     <ClInclude Include="src\utf8proc.h">
       <Filter>Text\Utf8Proc Header Files</Filter>
     </ClInclude>
+    <ClInclude Include="include\Poco\JSONFormatter.h">
+      <Filter>Logging\Header Files</Filter>
+    </ClInclude>
   </ItemGroup>
   <ItemGroup>
     <ResourceCompile Include="src\pocomsg.rc">

Foundation/Foundation_vs170.vcxproj

@@ -1275,6 +1275,7 @@
     <ClCompile Include="src\inflate.c" />
     <ClCompile Include="src\InflatingStream.cpp" />
     <ClCompile Include="src\inftrees.c" />
+    <ClCompile Include="src\JSONFormatter.cpp" />
     <ClCompile Include="src\JSONString.cpp" />
     <ClCompile Include="src\Latin1Encoding.cpp" />
     <ClCompile Include="src\Latin2Encoding.cpp" />
@@ -2255,6 +2256,7 @@
     <ClInclude Include="include\Poco\HMACEngine.h" />
     <ClInclude Include="include\Poco\InflatingStream.h" />
     <ClInclude Include="include\Poco\Instantiator.h" />
+    <ClInclude Include="include\Poco\JSONFormatter.h" />
     <ClInclude Include="include\Poco\JSONString.h" />
     <ClInclude Include="include\Poco\KeyValueArgs.h" />
     <ClInclude Include="include\Poco\Latin1Encoding.h" />

Foundation/Foundation_vs170.vcxproj.filters

@@ -940,6 +940,9 @@
     <ClCompile Include="src\utf8proc_data.c">
       <Filter>Text\Utf8Proc Source Files</Filter>
     </ClCompile>
+    <ClCompile Include="src\JSONFormatter.cpp">
+      <Filter>Logging\Source Files</Filter>
+    </ClCompile>
   </ItemGroup>
   <ItemGroup>
     <ClInclude Include="include\Poco\Any.h">
@@ -1896,6 +1899,9 @@
     <ClInclude Include="src\utf8proc.h">
       <Filter>Text\Utf8Proc Header Files</Filter>
     </ClInclude>
+    <ClInclude Include="include\Poco\JSONFormatter.h">
+      <Filter>Logging\Header Files</Filter>
+    </ClInclude>
   </ItemGroup>
   <ItemGroup>
     <ResourceCompile Include="src\pocomsg.rc">

Foundation/Makefile

@@ -19,7 +19,7 @@ objects = ArchiveStrategy Ascii ASCIIEncoding AsyncChannel AsyncNotificationCent
 	NestedDiagnosticContext Notification NotificationCenter \
 	NotificationQueue PriorityNotificationQueue TimedNotificationQueue \
 	NullStream NumberFormatter NumberParser NumericString AbstractObserver \
-	Path PatternFormatter PIDFile Process ProcessRunner PurgeStrategy RWLock Random RandomStream \
+	Path PatternFormatter JSONFormatter PIDFile Process ProcessRunner PurgeStrategy RWLock Random RandomStream \
 	DirectoryIteratorStrategy RegularExpression RefCountedObject Runnable RotateStrategy \
 	SHA1Engine SHA2Engine Semaphore SharedLibrary SimpleFileChannel \
 	SignalHandler SplitterChannel SortedDirectoryIterator Stopwatch StreamChannel \

Foundation/include/Poco/JSONFormatter.h

@@ -0,0 +1,109 @@
+//
+// JSONFormatter.h
+//
+// Library: Foundation
+// Package: Logging
+// Module:  JSONFormatter
+//
+// Definition of the JSONFormatter class.
+//
+// Copyright (c) 2024, Applied Informatics Software Engineering GmbH.
+// and Contributors.
+//
+// SPDX-License-Identifier:	BSL-1.0
+//
+
+
+#ifndef Foundation_JSONFormatter_INCLUDED
+#define Foundation_JSONFormatter_INCLUDED
+
+
+#include "Poco/Foundation.h"
+#include "Poco/Formatter.h"
+#include "Poco/Message.h"
+#include <vector>
+
+
+namespace Poco {
+
+
+class Foundation_API JSONFormatter: public Formatter
+	/// This formatter formats log messages as compact 
+	/// (no unnecessary whitespace) single-line JSON strings.
+	///
+	/// The following JSON schema is used:
+	///     {
+	///         "timestamp": "2024-09-26T13:41:23.324461Z",
+	///         "source": "sample",
+	///         "level": "information",
+	///         "message": "This is a test message.",
+	///         "thread": 12,
+	///         "file": "source.cpp",
+	///         "line": 456,
+	///         "params": {
+	///             "prop1": "value1"
+	///         }
+	///     }
+	///
+	/// The "file" and "line" properties will only be included if the log
+	/// message contains a file name and line number.
+	///
+	/// The "params" object will only be included if custom parameters
+	/// have been added to the Message.
+{
+public:
+	using Ptr = AutoPtr<JSONFormatter>;
+
+	JSONFormatter() = default;
+		/// Creates a JSONFormatter.
+
+	~JSONFormatter() = default;
+		/// Destroys the JSONFormatter.
+
+	void format(const Message& msg, std::string& text);
+		/// Formats the message as a JSON string.
+
+	void setProperty(const std::string& name, const std::string& value);
+		/// Sets the property with the given name to the given value.
+		///
+		/// The following properties are supported:
+		///
+		///     * times: Specifies whether times are adjusted for local time
+		///       or taken as they are in UTC. Supported values are "local" and "UTC".
+		///     * thread: Specifies the value given for the thread. Can be
+		///       "none" (excluded), "name" (thread name), "id" (POCO thread ID) or "osid" 
+		///       (operating system thread ID).
+		///
+		/// If any other property name is given, a PropertyNotSupported
+		/// exception is thrown.
+
+	std::string getProperty(const std::string& name) const;
+		/// Returns the value of the property with the given name or
+		/// throws a PropertyNotSupported exception if the given
+		/// name is not recognized.
+
+	static const std::string PROP_TIMES;
+	static const std::string PROP_THREAD;
+
+protected:
+	std::string getThread(const Message& message) const;
+	static const std::string& getPriorityName(int prio);
+
+	enum ThreadFormat
+	{
+		JSONF_THREAD_NONE = 0,
+		JSONF_THREAD_NAME = 1,
+		JSONF_THREAD_ID = 2,
+		JSONF_THREAD_OS_ID = 3
+	};
+
+private:
+	bool _localTime = false;
+	ThreadFormat _threadFormat = JSONF_THREAD_ID;
+};
+
+
+} // namespace Poco
+
+
+#endif // Foundation_JSONFormatter_INCLUDED

Foundation/src/JSONFormatter.cpp

@@ -0,0 +1,182 @@
+//
+// JSONFormatter.cpp
+//
+// Library: Foundation
+// Package: Logging
+// Module:  JSONFormatter
+//
+// Copyright (c) 2024, Applied Informatics Software Engineering GmbH.
+// and Contributors.
+//
+// SPDX-License-Identifier:	BSL-1.0
+//
+
+
+#include "Poco/JSONFormatter.h"
+#include "Poco/JSONString.h"
+#include "Poco/Message.h"
+#include "Poco/String.h"
+#include "Poco/JSONString.h"
+#include "Poco/NumberFormatter.h"
+#include "Poco/DateTimeFormatter.h"
+#include "Poco/DateTimeFormat.h"
+#include "Poco/Timezone.h"
+
+
+namespace Poco {
+
+
+const std::string JSONFormatter::PROP_TIMES("times");
+const std::string JSONFormatter::PROP_THREAD("thread");
+
+
+void JSONFormatter::format(const Message& msg, std::string& text)
+{
+	Timestamp timestamp = msg.getTime();
+	int tzd = DateTimeFormatter::UTC;
+	if (_localTime)
+	{
+		tzd = Timezone::utcOffset();
+		tzd += Timezone::dst();
+		timestamp += tzd*Timestamp::resolution();
+	}
+
+	text += '{';
+	text += "\"timestamp\":\"";
+	text += Poco::DateTimeFormatter::format(timestamp, Poco::DateTimeFormat::ISO8601_FRAC_FORMAT, tzd);
+	text += "\",\"source\":";
+	text += toJSON(msg.getSource());
+	text += ",\"level\":\"";
+	text += getPriorityName(msg.getPriority());
+	text += "\",\"message\":";
+	text += toJSON(msg.getText());
+	if (_threadFormat != JSONF_THREAD_NONE)
+	{
+		text += ",\"thread\":";
+		text += getThread(msg);
+	}
+	if (msg.getSourceFile())
+	{
+		text += ",\"file\":";
+		text += toJSON(msg.getSourceFile());
+	}
+	if (msg.getSourceLine())
+	{
+		text += ",\"line\":\"";
+		text += Poco::NumberFormatter::format(msg.getSourceLine());
+		text += "\"";
+	}
+	if (!msg.getAll().empty())
+	{
+		text += ",\"params\":{";
+		const auto& props = msg.getAll();
+		bool first = true;
+		for (const auto& p: props)
+		{
+			if (!first) 
+				text += ',';
+			else
+				first = false;
+			text += toJSON(p.first);
+			text += ':';
+			text += toJSON(p.second);
+		}
+		text += '}';
+	}
+	text += '}';
+}
+
+
+void JSONFormatter::setProperty(const std::string& name, const std::string& value)
+{
+	if (name == PROP_TIMES)
+	{
+		if (Poco::icompare(value, "local"s) == 0)
+			_localTime = true;
+		else if (Poco::icompare(value, "utc"s) == 0)
+			_localTime = false;
+		else
+			throw Poco::InvalidArgumentException("Invalid times value (must be local or UTC)"s, value);
+	}
+	else if (name == PROP_THREAD)
+	{
+		if (Poco::icompare(value, "none"s) == 0)
+			_threadFormat = JSONF_THREAD_NONE;
+		else if (Poco::icompare(value, "name"s) == 0)
+			_threadFormat = JSONF_THREAD_NAME;
+		else if (Poco::icompare(value, "id"s) == 0)
+			_threadFormat = JSONF_THREAD_ID;
+		else if (Poco::icompare(value, "osid"s) == 0)
+			_threadFormat = JSONF_THREAD_OS_ID;
+		else
+			throw Poco::InvalidArgumentException("Invalid thread value (must be name, id or osID)"s, value);
+	}
+	else throw Poco::PropertyNotSupportedException(name);
+}
+
+
+std::string JSONFormatter::getProperty(const std::string& name) const
+{
+	if (name == PROP_TIMES)
+	{
+		return _localTime ? "local"s : "UTC"s;
+	}
+	else if (name == PROP_THREAD)
+	{
+		switch (_threadFormat)
+		{
+		case JSONF_THREAD_NONE:
+			return "none"s;
+		case JSONF_THREAD_NAME:
+			return "name"s;
+		case JSONF_THREAD_ID:
+			return "id"s;
+		case JSONF_THREAD_OS_ID:
+			return "osID"s;
+		default:
+			return "invalid"s;
+		}
+	}
+	else throw Poco::PropertyNotSupportedException(name);
+}
+
+
+std::string JSONFormatter::getThread(const Message& message) const
+{
+	switch (_threadFormat)
+	{
+		case JSONF_THREAD_NONE:
+			return ""s;
+		case JSONF_THREAD_NAME:
+			return toJSON(message.getThread());
+		case JSONF_THREAD_ID:
+			return Poco::NumberFormatter::format(message.getTid());
+		case JSONF_THREAD_OS_ID:
+			return Poco::NumberFormatter::format(message.getOsTid());
+		default:
+			return ""s;
+	}
+}
+
+
+const std::string& JSONFormatter::getPriorityName(int prio)
+{
+	static const std::string PRIORITY_NAMES[] = {
+		"none"s,
+		"fatal"s,
+		"critical"s,
+		"error"s,
+		"warning"s,
+		"notice"s,
+		"information"s,
+		"debug"s,
+		"trace"
+	};
+
+	poco_assert (prio >= Message::PRIO_FATAL && prio <= Message::PRIO_TRACE);
+
+	return PRIORITY_NAMES[prio];
+}
+
+
+} // namespace Poco

Foundation/src/LoggingFactory.cpp

@@ -29,6 +29,7 @@
 #include "Poco/WindowsConsoleChannel.h"
 #endif
 #include "Poco/PatternFormatter.h"
+#include "Poco/JSONFormatter.h"
 
 
 using namespace std::string_literals;
@@ -112,6 +113,7 @@ void LoggingFactory::registerBuiltins()
 #endif
 
 	_formatterFactory.registerClass("PatternFormatter"s, new Instantiator<PatternFormatter, Formatter>);
+	_formatterFactory.registerClass("JSONFormatter"s, new Instantiator<JSONFormatter, Formatter>);
 }