pkgs/unified_analytics/lib/src/log_handler.dart - tools - Git at Google

 // Copyright (c) 2023, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.

 import 'dart:convert';

 import 'package:clock/clock.dart';
 import 'package:file/file.dart';

 import 'constants.dart';
 import 'event.dart';
 import 'initializer.dart';

 /// Data class that will be returned when analyzing the
 /// persisted log file on the client's machine.
 class LogFileStats {
   /// The oldest timestamp in the log file.
   final DateTime startDateTime;

   /// Number of minutes from [startDateTime] to now using [clock].
   final int minsFromStartDateTime;

   /// The latest timestamp in the log file.
   final DateTime endDateTime;

   /// Number of minutes from [endDateTime] to now using [clock].
   final int minsFromEndDateTime;

   /// The number of unique session ids found in the log file.
   final int sessionCount;

   /// The map containing all of the flutter channels and a count
   /// of how many events were under each channel.
   ///
   /// ```
   /// {
   ///   'stable': 123,
   ///   'beta': 50,
   ///   'master': 5,
   /// }
   /// ```
   final Map<String, int> flutterChannelCount;

   /// The map containing all of the tools that have sent events
   /// and how many events were sent by each tool.
   ///
   /// ```
   /// {
   ///   'flutter-tool': 500,
   ///   'dart-tool': 45,
   ///   'vscode-plugins': 321,
   /// }
   /// ```
   final Map<String, int> toolCount;

   /// The map containing all of the events in the file along with
   /// how many times they have occured.
   ///
   /// ```
   /// {
   ///   'client_request': 345,
   ///   'hot_reload_time': 765,
   ///   'memory_info': 90,
   /// }
   /// ```
   final Map<String, int> eventCount;

   /// Total number of records in the log file.
   final int recordCount;

   /// Contains the data from the [LogHandler.logFileStats] method.
   const LogFileStats({
     required this.startDateTime,
     required this.minsFromStartDateTime,
     required this.endDateTime,
     required this.minsFromEndDateTime,
     required this.sessionCount,
     required this.flutterChannelCount,
     required this.toolCount,
     required this.recordCount,
     required this.eventCount,
   });

   /// Pass in a string label for one of the instance variables
   /// and return the integer value of that label.
   ///
   /// If label passed for [DateTime] instance variable, integer
   /// in the form of [DateTime.millisecondsSinceEpoch] will be
   /// returned.
   ///
   /// Returns null if the label passed does not match anything.
   int? getValueByString(String label) {
     // When querying counts, the label will include the
     // key for the appropriate map
     //
     // Example: logFileStats.toolCount.flutter-tool is asking
     //   for the number of events sent via flutter cli
     final parts = label.split('.');
     String? key;
     if (parts.length >= 3) {
       // Assign the first two parts of the string as the label
       // ie. logFileStats.toolCount.flutter-tool -> logFileStats.toolCount
       label = parts.sublist(0, 2).join('.');
       key = parts.sublist(2, parts.length).join('.');
     }

     switch (label) {
       case 'logFileStats.startDateTime':
         return startDateTime.millisecondsSinceEpoch;
       case 'logFileStats.minsFromStartDateTime':
         return minsFromStartDateTime;
       case 'logFileStats.endDateTime':
         return endDateTime.millisecondsSinceEpoch;
       case 'logFileStats.minsFromEndDateTime':
         return minsFromEndDateTime;
       case 'logFileStats.sessionCount':
         return sessionCount;
       case 'logFileStats.recordCount':
         return recordCount;
       case 'logFileStats.flutterChannelCount':
         if (key != null && flutterChannelCount.containsKey(key)) {
           return flutterChannelCount[key];
         }
       case 'logFileStats.toolCount':
         if (key != null && toolCount.containsKey(key)) {
           return toolCount[key];
         }
       case 'logFileStats.eventCount':
         if (key != null && eventCount.containsKey(key)) {
           return eventCount[key];
         }
     }

     return null;
   }

   @override
   String toString() {
     final encoder = const JsonEncoder.withIndent('  ');
     return encoder.convert({
       'startDateTime': startDateTime.toString(),
       'minsFromStartDateTime': minsFromStartDateTime,
       'endDateTime': endDateTime.toString(),
       'minsFromEndDateTime': minsFromEndDateTime,
       'sessionCount': sessionCount,
       'recordCount': recordCount,
       'eventCount': eventCount,
       'toolCount': toolCount,
       'flutterChannelCount': flutterChannelCount,
     });
   }
 }

 /// This class is responsible for writing to a log
 /// file that has been initialized by the [createLogFile].
 ///
 /// It will be treated as an append only log and will be limited
 /// to have has many data records as specified by [kLogFileLength].
 class LogHandler {
   final File logFile;

   /// Contains instances of [Event.analyticsException] that were encountered
   /// during a workflow and will be sent to GA4 for collection.
   final Set<Event> errorSet = {};

   /// A log handler constructor that will delegate saving
   /// logs and retrieving stats from the persisted log.
   LogHandler({required this.logFile});

   /// Get stats from the persisted log file.
   ///
   /// Note that some developers may only be Dart
   /// developers and will not have any data for flutter
   /// related metrics.
   LogFileStats? logFileStats() {
     // Parse each line of the log file through [LogItem],
     // some returned records may be null if malformed, they will be
     // removed later through `whereType<LogItem>`
     final records = logFile
         .readAsLinesSync()
         .map((String e) {
           try {
             return LogItem.fromRecord(jsonDecode(e) as Map<String, Object?>);
           } on FormatException catch (err) {
             errorSet.add(Event.analyticsException(
               workflow: 'LogFileStats.logFileStats',
               error: err.runtimeType.toString(),
               description: 'message: ${err.message}\nsource: ${err.source}',
             ));

             return null;
             // ignore: avoid_catching_errors
           } on TypeError catch (err) {
             errorSet.add(Event.analyticsException(
               workflow: 'LogFileStats.logFileStats',
               error: err.runtimeType.toString(),
             ));

             return null;
           }
         })
         .whereType<LogItem>()
         .toList();

     if (records.isEmpty) return null;

     // Get the start and end dates for the log file
     final startDateTime = records.first.localTime;
     final endDateTime = records.last.localTime;

     // Map with counters for user properties
     final counter = <String, Set<Object>>{
       'sessions': <int>{},
       'flutter_channel': <String>{},
       'tool': <String>{},
     };

     // Map of counters for each event
     final eventCount = <String, int>{};
     final flutterChannelCount = <String, int>{};
     final toolCount = <String, int>{};
     for (var record in records) {
       counter['sessions']!.add(record.sessionId);
       counter['tool']!.add(record.tool);
       if (record.flutterChannel != null) {
         counter['flutter_channel']!.add(record.flutterChannel!);
       }

       // Count each event, if it doesn't exist in the [eventCount]
       // it will be added first
       if (!eventCount.containsKey(record.eventName)) {
         eventCount[record.eventName] = 0;
       }
       eventCount[record.eventName] = eventCount[record.eventName]! + 1;

       // Counting how many events were recorded for each tool
       if (!toolCount.containsKey(record.tool)) {
         toolCount[record.tool] = 0;
       }
       toolCount[record.tool] = toolCount[record.tool]! + 1;

       // Necessary to perform a null check for flutter channel because
       // not all events will have information about flutter
       if (record.flutterChannel != null) {
         final flutterChannel = record.flutterChannel!;
         if (!flutterChannelCount.containsKey(flutterChannel)) {
           flutterChannelCount[flutterChannel] = 0;
         }

         flutterChannelCount[flutterChannel] =
             flutterChannelCount[flutterChannel]! + 1;
       }
     }

     final now = clock.now();

     return LogFileStats(
       startDateTime: startDateTime,
       minsFromStartDateTime: now.difference(startDateTime).inMinutes,
       endDateTime: endDateTime,
       minsFromEndDateTime: now.difference(endDateTime).inMinutes,
       sessionCount: counter['sessions']!.length,
       flutterChannelCount: flutterChannelCount,
       toolCount: toolCount,
       eventCount: eventCount,
       recordCount: records.length,
     );
   }

   /// Saves the data passed in as a single line in the log file.
   ///
   /// This will keep the max number of records limited to equal to
   /// or less than [kLogFileLength] records.
   void save({required Map<String, Object?> data}) {
     var records = logFile.readAsLinesSync();
     final content = '${jsonEncode(data)}\n';

     // When the record count is less than the max, add as normal;
     // else drop the oldest records until equal to max
     if (records.length < kLogFileLength) {
       logFile.writeAsStringSync(content, mode: FileMode.writeOnlyAppend);
     } else {
       records.add(content);
       records = records.skip(records.length - kLogFileLength).toList();

       logFile.writeAsStringSync(records.join('\n'));
     }
   }
 }

 /// Data class for each record persisted on the client's machine.
 class LogItem {
   final String eventName;
   final int sessionId;
   final String? flutterChannel;
   final String host;
   final String? flutterVersion;
   final String dartVersion;
   final String tool;
   final DateTime localTime;
   final String hostOsVersion;
   final String locale;
   final String? clientIde;

   LogItem({
     required this.eventName,
     required this.sessionId,
     this.flutterChannel,
     required this.host,
     this.flutterVersion,
     required this.dartVersion,
     required this.tool,
     required this.localTime,
     required this.hostOsVersion,
     required this.locale,
     required this.clientIde,
   });

   /// Serves a parser for each record in the log file.
   ///
   /// Using this method guarantees that we have parsed out
   /// fields that are necessary for the [LogHandler.logFileStats]
   /// method.
   ///
   /// If the returned value is null, that indicates a malformed
   /// record which can be discarded during analysis.
   ///
   /// Example of what a record looks like:
   /// ```
   /// {
   ///     "client_id": "ffcea97b-db5e-4c66-98c2-3942de4fac40",
   ///     "events": [
   ///         {
   ///             "name": "hot_reload_time",
   ///             "params": {
   ///                 "timeMs": 135
   ///             }
   ///         }
   ///     ],
   ///     "user_properties": {
   ///         "session_id": {
   ///             "value": 1699385899950
   ///         },
   ///         "flutter_channel": {
   ///             "value": "ey-test-channel"
   ///         },
   ///         "host": {
   ///             "value": "macOS"
   ///         },
   ///         "flutter_version": {
   ///             "value": "Flutter 3.6.0-7.0.pre.47"
   ///         },
   ///         "dart_version": {
   ///             "value": "Dart 2.19.0"
   ///         },
   ///         "analytics_pkg_version": {
   ///             "value": "5.2.0"
   ///         },
   ///         "tool": {
   ///             "value": "flutter-tool"
   ///         },
   ///         "local_time": {
   ///             "value": "2023-11-07 15:09:03.025559 -0500"
   ///         },
   ///         "host_os_version": {
   ///             "value": "Version 14.1 (Build 23B74)"
   ///         },
   ///         "locale": {
   ///             "value": "en"
   ///         },
   ///         "clientIde": {
   ///             "value": "VSCode"
   ///         }
   ///     }
   /// }
   /// ```
   static LogItem? fromRecord(Map<String, Object?> record) {
     if (!record.containsKey('user_properties') ||
         !record.containsKey('events')) {
       return null;
     }

     // Parse out values from the top level key = 'events' and return
     // a map for the one event in the value
     final eventProp =
         (record['events']! as List<Object?>).first as Map<String, Object?>;
     final eventName = eventProp['name'] as String;

     // Parse the data out of the `user_properties` value
     final userProps = record['user_properties'] as Map<String, Object?>;

     // Parse out the values from the top level key = 'user_properties`
     final sessionId =
         (userProps['session_id']! as Map<String, Object?>)['value'] as int?;
     final flutterChannel = (userProps['flutter_channel']!
         as Map<String, Object?>)['value'] as String?;
     final host =
         (userProps['host']! as Map<String, Object?>)['value'] as String?;
     final flutterVersion = (userProps['flutter_version']!
         as Map<String, Object?>)['value'] as String?;
     final dartVersion = (userProps['dart_version']!
         as Map<String, Object?>)['value'] as String?;
     final tool =
         (userProps['tool']! as Map<String, Object?>)['value'] as String?;
     final localTimeString =
         (userProps['local_time']! as Map<String, Object?>)['value'] as String?;
     final hostOsVersion = (userProps['host_os_version']!
         as Map<String, Object?>)['value'] as String?;
     final locale =
         (userProps['locale']! as Map<String, Object?>)['value'] as String?;
     final clientIde =
         (userProps['client_ide']! as Map<String, Object?>)['value'] as String?;

     // If any of the above values are null, return null since that
     // indicates the record is malformed; note that `flutter_version`,
     // `flutter_channel`, and `client_ide` are nullable fields in the log file
     final values = <Object?>[
       // Values associated with the top level key = 'events'
       eventName,

       // Values associated with the top level key = 'events'
       sessionId,
       host,
       dartVersion,
       tool,
       localTimeString,
       hostOsVersion,
       locale,
     ];
     for (var value in values) {
       if (value == null) return null;
     }

     // Parse the local time from the string extracted
     final localTime = DateTime.parse(localTimeString!).toLocal();

     return LogItem(
       eventName: eventName,
       sessionId: sessionId!,
       flutterChannel: flutterChannel,
       host: host!,
       flutterVersion: flutterVersion,
       dartVersion: dartVersion!,
       tool: tool!,
       localTime: localTime,
       hostOsVersion: hostOsVersion!,
       locale: locale!,
       clientIde: clientIde,
     );
   }
 }
	// Copyright (c) 2023, the Dart project authors. Please see the AUTHORS file
	// for details. All rights reserved. Use of this source code is governed by a
	// BSD-style license that can be found in the LICENSE file.

	import 'dart:convert';

	import 'package:clock/clock.dart';
	import 'package:file/file.dart';

	import 'constants.dart';
	import 'event.dart';
	import 'initializer.dart';

	/// Data class that will be returned when analyzing the
	/// persisted log file on the client's machine.
	class LogFileStats {
	/// The oldest timestamp in the log file.
	final DateTime startDateTime;

	/// Number of minutes from [startDateTime] to now using [clock].
	final int minsFromStartDateTime;

	/// The latest timestamp in the log file.
	final DateTime endDateTime;

	/// Number of minutes from [endDateTime] to now using [clock].
	final int minsFromEndDateTime;

	/// The number of unique session ids found in the log file.
	final int sessionCount;

	/// The map containing all of the flutter channels and a count
	/// of how many events were under each channel.
	///
	/// ```
	/// {
	/// 'stable': 123,
	/// 'beta': 50,
	/// 'master': 5,
	/// }
	/// ```
	final Map<String, int> flutterChannelCount;

	/// The map containing all of the tools that have sent events
	/// and how many events were sent by each tool.
	///
	/// ```
	/// {
	/// 'flutter-tool': 500,
	/// 'dart-tool': 45,
	/// 'vscode-plugins': 321,
	/// }
	/// ```
	final Map<String, int> toolCount;

	/// The map containing all of the events in the file along with
	/// how many times they have occured.
	///
	/// ```
	/// {
	/// 'client_request': 345,
	/// 'hot_reload_time': 765,
	/// 'memory_info': 90,
	/// }
	/// ```
	final Map<String, int> eventCount;

	/// Total number of records in the log file.
	final int recordCount;

	/// Contains the data from the [LogHandler.logFileStats] method.
	const LogFileStats({
	required this.startDateTime,
	required this.minsFromStartDateTime,
	required this.endDateTime,
	required this.minsFromEndDateTime,
	required this.sessionCount,
	required this.flutterChannelCount,
	required this.toolCount,
	required this.recordCount,
	required this.eventCount,
	});

	/// Pass in a string label for one of the instance variables
	/// and return the integer value of that label.
	///
	/// If label passed for [DateTime] instance variable, integer
	/// in the form of [DateTime.millisecondsSinceEpoch] will be
	/// returned.
	///
	/// Returns null if the label passed does not match anything.
	int? getValueByString(String label) {
	// When querying counts, the label will include the
	// key for the appropriate map
	//
	// Example: logFileStats.toolCount.flutter-tool is asking
	// for the number of events sent via flutter cli
	final parts = label.split('.');
	String? key;
	if (parts.length >= 3) {
	// Assign the first two parts of the string as the label
	// ie. logFileStats.toolCount.flutter-tool -> logFileStats.toolCount
	label = parts.sublist(0, 2).join('.');
	key = parts.sublist(2, parts.length).join('.');
	}

	switch (label) {
	case 'logFileStats.startDateTime':
	return startDateTime.millisecondsSinceEpoch;
	case 'logFileStats.minsFromStartDateTime':
	return minsFromStartDateTime;
	case 'logFileStats.endDateTime':
	return endDateTime.millisecondsSinceEpoch;
	case 'logFileStats.minsFromEndDateTime':
	return minsFromEndDateTime;
	case 'logFileStats.sessionCount':
	return sessionCount;
	case 'logFileStats.recordCount':
	return recordCount;
	case 'logFileStats.flutterChannelCount':
	if (key != null && flutterChannelCount.containsKey(key)) {
	return flutterChannelCount[key];
	}
	case 'logFileStats.toolCount':
	if (key != null && toolCount.containsKey(key)) {
	return toolCount[key];
	}
	case 'logFileStats.eventCount':
	if (key != null && eventCount.containsKey(key)) {
	return eventCount[key];
	}
	}

	return null;
	}

	@override
	String toString() {
	final encoder = const JsonEncoder.withIndent(' ');
	return encoder.convert({
	'startDateTime': startDateTime.toString(),
	'minsFromStartDateTime': minsFromStartDateTime,
	'endDateTime': endDateTime.toString(),
	'minsFromEndDateTime': minsFromEndDateTime,
	'sessionCount': sessionCount,
	'recordCount': recordCount,
	'eventCount': eventCount,
	'toolCount': toolCount,
	'flutterChannelCount': flutterChannelCount,
	});
	}
	}

	/// This class is responsible for writing to a log
	/// file that has been initialized by the [createLogFile].
	///
	/// It will be treated as an append only log and will be limited
	/// to have has many data records as specified by [kLogFileLength].
	class LogHandler {
	final File logFile;

	/// Contains instances of [Event.analyticsException] that were encountered
	/// during a workflow and will be sent to GA4 for collection.
	final Set<Event> errorSet = {};

	/// A log handler constructor that will delegate saving
	/// logs and retrieving stats from the persisted log.
	LogHandler({required this.logFile});

	/// Get stats from the persisted log file.
	///
	/// Note that some developers may only be Dart
	/// developers and will not have any data for flutter
	/// related metrics.
	LogFileStats? logFileStats() {
	// Parse each line of the log file through [LogItem],
	// some returned records may be null if malformed, they will be
	// removed later through `whereType<LogItem>`
	final records = logFile
	.readAsLinesSync()
	.map((String e) {
	try {
	return LogItem.fromRecord(jsonDecode(e) as Map<String, Object?>);
	} on FormatException catch (err) {
	errorSet.add(Event.analyticsException(
	workflow: 'LogFileStats.logFileStats',
	error: err.runtimeType.toString(),
	description: 'message: ${err.message}\nsource: ${err.source}',
	));

	return null;
	// ignore: avoid_catching_errors
	} on TypeError catch (err) {
	errorSet.add(Event.analyticsException(
	workflow: 'LogFileStats.logFileStats',
	error: err.runtimeType.toString(),
	));

	return null;
	}
	})
	.whereType<LogItem>()
	.toList();

	if (records.isEmpty) return null;

	// Get the start and end dates for the log file
	final startDateTime = records.first.localTime;
	final endDateTime = records.last.localTime;

	// Map with counters for user properties
	final counter = <String, Set<Object>>{
	'sessions': <int>{},
	'flutter_channel': <String>{},
	'tool': <String>{},
	};

	// Map of counters for each event
	final eventCount = <String, int>{};
	final flutterChannelCount = <String, int>{};
	final toolCount = <String, int>{};
	for (var record in records) {
	counter['sessions']!.add(record.sessionId);
	counter['tool']!.add(record.tool);
	if (record.flutterChannel != null) {
	counter['flutter_channel']!.add(record.flutterChannel!);
	}

	// Count each event, if it doesn't exist in the [eventCount]
	// it will be added first
	if (!eventCount.containsKey(record.eventName)) {
	eventCount[record.eventName] = 0;
	}
	eventCount[record.eventName] = eventCount[record.eventName]! + 1;

	// Counting how many events were recorded for each tool
	if (!toolCount.containsKey(record.tool)) {
	toolCount[record.tool] = 0;
	}
	toolCount[record.tool] = toolCount[record.tool]! + 1;

	// Necessary to perform a null check for flutter channel because
	// not all events will have information about flutter
	if (record.flutterChannel != null) {
	final flutterChannel = record.flutterChannel!;
	if (!flutterChannelCount.containsKey(flutterChannel)) {
	flutterChannelCount[flutterChannel] = 0;
	}

	flutterChannelCount[flutterChannel] =
	flutterChannelCount[flutterChannel]! + 1;
	}
	}

	final now = clock.now();

	return LogFileStats(
	startDateTime: startDateTime,
	minsFromStartDateTime: now.difference(startDateTime).inMinutes,
	endDateTime: endDateTime,
	minsFromEndDateTime: now.difference(endDateTime).inMinutes,
	sessionCount: counter['sessions']!.length,
	flutterChannelCount: flutterChannelCount,
	toolCount: toolCount,
	eventCount: eventCount,
	recordCount: records.length,
	);
	}

	/// Saves the data passed in as a single line in the log file.
	///
	/// This will keep the max number of records limited to equal to
	/// or less than [kLogFileLength] records.
	void save({required Map<String, Object?> data}) {
	var records = logFile.readAsLinesSync();
	final content = '${jsonEncode(data)}\n';

	// When the record count is less than the max, add as normal;
	// else drop the oldest records until equal to max
	if (records.length < kLogFileLength) {
	logFile.writeAsStringSync(content, mode: FileMode.writeOnlyAppend);
	} else {
	records.add(content);
	records = records.skip(records.length - kLogFileLength).toList();

	logFile.writeAsStringSync(records.join('\n'));
	}
	}
	}

	/// Data class for each record persisted on the client's machine.
	class LogItem {
	final String eventName;
	final int sessionId;
	final String? flutterChannel;
	final String host;
	final String? flutterVersion;
	final String dartVersion;
	final String tool;
	final DateTime localTime;
	final String hostOsVersion;
	final String locale;
	final String? clientIde;

	LogItem({
	required this.eventName,
	required this.sessionId,
	this.flutterChannel,
	required this.host,
	this.flutterVersion,
	required this.dartVersion,
	required this.tool,
	required this.localTime,
	required this.hostOsVersion,
	required this.locale,
	required this.clientIde,
	});

	/// Serves a parser for each record in the log file.
	///
	/// Using this method guarantees that we have parsed out
	/// fields that are necessary for the [LogHandler.logFileStats]
	/// method.
	///
	/// If the returned value is null, that indicates a malformed
	/// record which can be discarded during analysis.
	///
	/// Example of what a record looks like:
	/// ```
	/// {
	/// "client_id": "ffcea97b-db5e-4c66-98c2-3942de4fac40",
	/// "events": [
	/// {
	/// "name": "hot_reload_time",
	/// "params": {
	/// "timeMs": 135
	/// }
	/// }
	/// ],
	/// "user_properties": {
	/// "session_id": {
	/// "value": 1699385899950
	/// },
	/// "flutter_channel": {
	/// "value": "ey-test-channel"
	/// },
	/// "host": {
	/// "value": "macOS"
	/// },
	/// "flutter_version": {
	/// "value": "Flutter 3.6.0-7.0.pre.47"
	/// },
	/// "dart_version": {
	/// "value": "Dart 2.19.0"
	/// },
	/// "analytics_pkg_version": {
	/// "value": "5.2.0"
	/// },
	/// "tool": {
	/// "value": "flutter-tool"
	/// },
	/// "local_time": {
	/// "value": "2023-11-07 15:09:03.025559 -0500"
	/// },
	/// "host_os_version": {
	/// "value": "Version 14.1 (Build 23B74)"
	/// },
	/// "locale": {
	/// "value": "en"
	/// },
	/// "clientIde": {
	/// "value": "VSCode"
	/// }
	/// }
	/// }
	/// ```
	static LogItem? fromRecord(Map<String, Object?> record) {
	if (!record.containsKey('user_properties') \|\|
	!record.containsKey('events')) {
	return null;
	}

	// Parse out values from the top level key = 'events' and return
	// a map for the one event in the value
	final eventProp =
	(record['events']! as List<Object?>).first as Map<String, Object?>;
	final eventName = eventProp['name'] as String;

	// Parse the data out of the `user_properties` value
	final userProps = record['user_properties'] as Map<String, Object?>;

	// Parse out the values from the top level key = 'user_properties`
	final sessionId =
	(userProps['session_id']! as Map<String, Object?>)['value'] as int?;
	final flutterChannel = (userProps['flutter_channel']!
	as Map<String, Object?>)['value'] as String?;
	final host =
	(userProps['host']! as Map<String, Object?>)['value'] as String?;
	final flutterVersion = (userProps['flutter_version']!
	as Map<String, Object?>)['value'] as String?;
	final dartVersion = (userProps['dart_version']!
	as Map<String, Object?>)['value'] as String?;
	final tool =
	(userProps['tool']! as Map<String, Object?>)['value'] as String?;
	final localTimeString =
	(userProps['local_time']! as Map<String, Object?>)['value'] as String?;
	final hostOsVersion = (userProps['host_os_version']!
	as Map<String, Object?>)['value'] as String?;
	final locale =
	(userProps['locale']! as Map<String, Object?>)['value'] as String?;
	final clientIde =
	(userProps['client_ide']! as Map<String, Object?>)['value'] as String?;

	// If any of the above values are null, return null since that
	// indicates the record is malformed; note that `flutter_version`,
	// `flutter_channel`, and `client_ide` are nullable fields in the log file
	final values = <Object?>[
	// Values associated with the top level key = 'events'
	eventName,

	// Values associated with the top level key = 'events'
	sessionId,
	host,
	dartVersion,
	tool,
	localTimeString,
	hostOsVersion,
	locale,
	];
	for (var value in values) {
	if (value == null) return null;
	}

	// Parse the local time from the string extracted
	final localTime = DateTime.parse(localTimeString!).toLocal();

	return LogItem(
	eventName: eventName,
	sessionId: sessionId!,
	flutterChannel: flutterChannel,
	host: host!,
	flutterVersion: flutterVersion,
	dartVersion: dartVersion!,
	tool: tool!,
	localTime: localTime,
	hostOsVersion: hostOsVersion!,
	locale: locale!,
	clientIde: clientIde,
	);
	}
	}