Dart Logging

https://pub.dev/documentation/logging/latest
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Dart Logging is a library for generating and managing log messages with configurable levels,...
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### config(Object? message, [Object? error, StackTrace? stackTrace])

Source: https://pub.dev/documentation/logging/latest/logging/Logger-class.html

Logs a message at the Level.CONFIG level.

```APIDOC
## config(Object? message, [Object? error, StackTrace? stackTrace])

### Description
Log message at level Level.CONFIG.

### Method
config(Object? message, [Object? error, StackTrace? stackTrace])

### Parameters
- **message** (Object?) - Required - The message to log.
- **error** (Object?) - Optional - An error object associated with the log.
- **stackTrace** (StackTrace?) - Optional - The stack trace associated with the log.

### Returns
void
```

--------------------------------

### LogRecord constructor

Source: https://pub.dev/documentation/logging/latest/logging/LogRecord-class.html

Creates a LogRecord instance with the specified level, message, logger name, and optional error, stack trace, zone, and object.

```APIDOC
## LogRecord(Level level, String message, String loggerName, [Object? error, StackTrace? stackTrace, Zone? zone, Object? object])

### Description
Creates a new LogRecord with the given level, message, and logger name. Optional parameters include an associated error, stack trace, zone, and non-string object.

### Parameters
- **level** (Level) - Required - The severity level of the log record.
- **message** (String) - Required - The log message.
- **loggerName** (String) - Required - The name of the logger that created this record.
- **error** (Object?) - Optional - An associated error object, if any.
- **stackTrace** (StackTrace?) - Optional - The stack trace associated with the error, if any.
- **zone** (Zone?) - Optional - The zone of the calling code.
- **object** (Object?) - Optional - A non-string message object passed to the logger.

### Example
```dart
LogRecord(Level.INFO, 'User logged in', 'myLogger');
```
```

--------------------------------

### Create a logger

Source: https://pub.dev/documentation/logging/latest/index.html

Initializes a new Logger instance with a unique name.

```dart
final log = Logger('MyClassName');
```

--------------------------------

### fine(Object? message, [Object? error, StackTrace? stackTrace])

Source: https://pub.dev/documentation/logging/latest/logging/Logger-class.html

Logs a message at the Level.FINE level.

```APIDOC
## fine(Object? message, [Object? error, StackTrace? stackTrace])

### Description
Log message at level Level.FINE.

### Method
fine(Object? message, [Object? error, StackTrace? stackTrace])

### Parameters
- **message** (Object?) - Required - The message to log.
- **error** (Object?) - Optional - An error object associated with the log.
- **stackTrace** (StackTrace?) - Optional - The stack trace associated with the log.

### Returns
void
```

--------------------------------

### Configure hierarchical logging

Source: https://pub.dev/documentation/logging/latest/index.html

Enables hierarchical logging and demonstrates how individual loggers inherit or override root configurations.

```dart
  hierarchicalLoggingEnabled = true;
  Logger.root.level = Level.WARNING;
  Logger.root.onRecord.listen((record) {
    print('[ROOT][WARNING+] ${record.message}');
  });

  final log1 = Logger('FINE+');
  log1.level = Level.FINE;
  log1.onRecord.listen((record) {
    print('[LOG1][FINE+] ${record.message}');
  });

  // log2 inherits LEVEL value of WARNING from `Logger.root`
  final log2 = Logger('WARNING+');
  log2.onRecord.listen((record) {
    print('[LOG2][WARNING+] ${record.message}');
  });


  // Will NOT print because FINER is too low level for `Logger.root`.
  log1.finer('LOG_01 FINER (X)');

  // Will print twice ([LOG1] & [ROOT])
  log1.fine('LOG_01 FINE (√√)');

  // Will print ONCE because `log1` only uses root listener.
  log1.warning('LOG_01 WARNING (√)');

  // Will never print because FINE is too low level.
  log2.fine('LOG_02 FINE (X)');

  // Will print twice ([LOG2] & [ROOT]) because warning is sufficient for all
  // loggers' levels.
  log2.warning('LOG_02 WARNING (√√)');

  // Will never print because `info` is filtered by `Logger.root.level` of
  // `Level.WARNING`.
  log2.info('INFO (X)');
```

```text
[LOG1][FINE+] LOG_01 FINE (√√)
[ROOT][WARNING+] LOG_01 FINE (√√)
[LOG1][FINE+] LOG_01 WARNING (√)
[ROOT][WARNING+] LOG_01 WARNING (√)
[LOG2][WARNING+] LOG_02 WARNING (√√)
[ROOT][WARNING+] LOG_02 WARNING (√√)
```

--------------------------------

### info(Object? message, [Object? error, StackTrace? stackTrace])

Source: https://pub.dev/documentation/logging/latest/logging/Logger-class.html

Logs a message at the Level.INFO level.

```APIDOC
## info(Object? message, [Object? error, StackTrace? stackTrace])

### Description
Log message at level Level.INFO.

### Method
info(Object? message, [Object? error, StackTrace? stackTrace])

### Parameters
- **message** (Object?) - Required - The message to log.
- **error** (Object?) - Optional - An error object associated with the log.
- **stackTrace** (StackTrace?) - Optional - The stack trace associated with the log.

### Returns
void
```

--------------------------------

### Configure root logger

Source: https://pub.dev/documentation/logging/latest/index.html

Sets the root logger level and adds a print handler to the onRecord stream.

```dart
Logger.root.level = Level.ALL; // defaults to Level.INFO
Logger.root.onRecord.listen((record) {
  print('${record.level.name}: ${record.time}: ${record.message}');
});
```

--------------------------------

### warning(Object? message, [Object? error, StackTrace? stackTrace])

Source: https://pub.dev/documentation/logging/latest/logging/Logger-class.html

Logs a message at the Level.WARNING level.

```APIDOC
## warning(Object? message, [Object? error, StackTrace? stackTrace])

### Description
Log message at level Level.WARNING.

### Method
warning(Object? message, [Object? error, StackTrace? stackTrace])

### Parameters
- **message** (Object?) - Required - The message to log.
- **error** (Object?) - Optional - An error object associated with the log.
- **stackTrace** (StackTrace?) - Optional - The stack trace associated with the log.

### Returns
void
```

--------------------------------

### Level constants

Source: https://pub.dev/documentation/logging/latest/logging/Level-class.html

Predefined Level constants for controlling logging output.

```APIDOC
## Level Constants

### ALL → const Level
Special key to turn on logging for all levels (value = 0).

### CONFIG → const Level
Key for static configuration messages (value = 700).

### FINE → const Level
Key for tracing information (value = 500).

### FINER → const Level
Key for fairly detailed tracing (value = 400).

### FINEST → const Level
Key for highly detailed tracing (value = 300).

### INFO → const Level
Key for informational messages (value = 800).

### LEVELS → const List<Level>
List of all predefined levels.

### OFF → const Level
Special key to turn off all logging (value = 2000).

### SEVERE → const Level
Key for serious failures (value = 1000).

### SHOUT → const Level
Key for extra debugging loudness (value = 1200).

### WARNING → const Level
Key for potential problems (value = 900).
```

--------------------------------

### Logger(String name)

Source: https://pub.dev/documentation/logging/latest/logging/Logger-class.html

Factory constructor that creates or finds a Logger by its hierarchical dot-separated name.

```APIDOC
## Logger(String name)

### Description
Create or find a Logger by name. Loggers are named using a hierarchical dot-separated name convention.

### Constructor
Logger(String name)

### Parameters
- **name** (String) - Required - The hierarchical name of the logger.

### Returns
A Logger instance.
```

--------------------------------

### Level constructor

Source: https://pub.dev/documentation/logging/latest/logging/Level-class.html

Creates a new Level instance with a given name and integer value. The value is used for ordering and filtering.

```APIDOC
## Level(String name, int value)

### Description
Creates a new Level instance with the specified name and integer value. The value is used to order levels for filtering.

### Constructor
Level(String name, int value)

### Parameters
- **name** (String) - Required - The name of the level.
- **value** (int) - Required - The integer value used for ordering and filtering.

### Example
```dart
final myLevel = Level('MY_LEVEL', 600);
```
```

--------------------------------

### Level methods

Source: https://pub.dev/documentation/logging/latest/logging/Level-class.html

Methods of the Level class: compareTo, toString, and noSuchMethod.

```APIDOC
## Level Methods

### compareTo(Level other) → int
Compares this object to another object. Returns an integer indicating the order.

### toString() → String
Returns a string representation of this object.

### noSuchMethod(Invocation invocation) → dynamic
Invoked when a nonexistent method or property is accessed.
```

--------------------------------

### finer(Object? message, [Object? error, StackTrace? stackTrace])

Source: https://pub.dev/documentation/logging/latest/logging/Logger-class.html

Logs a message at the Level.FINER level.

```APIDOC
## finer(Object? message, [Object? error, StackTrace? stackTrace])

### Description
Log message at level Level.FINER.

### Method
finer(Object? message, [Object? error, StackTrace? stackTrace])

### Parameters
- **message** (Object?) - Required - The message to log.
- **error** (Object?) - Optional - An error object associated with the log.
- **stackTrace** (StackTrace?) - Optional - The stack trace associated with the log.

### Returns
void
```

--------------------------------

### LogRecord methods

Source: https://pub.dev/documentation/logging/latest/logging/LogRecord-class.html

Methods available on LogRecord, including toString which provides a string representation of the object.

```APIDOC
## LogRecord Methods

### toString() → String
Returns a string representation of this object. (override)

### noSuchMethod(Invocation invocation) → dynamic
Invoked when a nonexistent method or property is accessed. (inherited)
```

--------------------------------

### finest(Object? message, [Object? error, StackTrace? stackTrace])

Source: https://pub.dev/documentation/logging/latest/logging/Logger-class.html

Logs a message at the Level.FINEST level.

```APIDOC
## finest(Object? message, [Object? error, StackTrace? stackTrace])

### Description
Log message at level Level.FINEST.

### Method
finest(Object? message, [Object? error, StackTrace? stackTrace])

### Parameters
- **message** (Object?) - Required - The message to log.
- **error** (Object?) - Optional - An error object associated with the log.
- **stackTrace** (StackTrace?) - Optional - The stack trace associated with the log.

### Returns
void
```

--------------------------------

### shout(Object? message, [Object? error, StackTrace? stackTrace])

Source: https://pub.dev/documentation/logging/latest/logging/Logger-class.html

Logs a message at the Level.SHOUT level.

```APIDOC
## shout(Object? message, [Object? error, StackTrace? stackTrace])

### Description
Log message at level Level.SHOUT.

### Method
shout(Object? message, [Object? error, StackTrace? stackTrace])

### Parameters
- **message** (Object?) - Required - The message to log.
- **error** (Object?) - Optional - An error object associated with the log.
- **stackTrace** (StackTrace?) - Optional - The stack trace associated with the log.

### Returns
void
```

--------------------------------

### severe(Object? message, [Object? error, StackTrace? stackTrace])

Source: https://pub.dev/documentation/logging/latest/logging/Logger-class.html

Logs a message at the Level.SEVERE level.

```APIDOC
## severe(Object? message, [Object? error, StackTrace? stackTrace])

### Description
Log message at level Level.SEVERE.

### Method
severe(Object? message, [Object? error, StackTrace? stackTrace])

### Parameters
- **message** (Object?) - Required - The message to log.
- **error** (Object?) - Optional - An error object associated with the log.
- **stackTrace** (StackTrace?) - Optional - The stack trace associated with the log.

### Returns
void
```

--------------------------------

### Level operators

Source: https://pub.dev/documentation/logging/latest/logging/Level-class.html

Comparison operators for Level: <, <=, ==, >, >=.

```APIDOC
## Level Operators

### operator <(Level other) → bool
Returns true if this level's value is less than the other's.

### operator <=(Level other) → bool
Returns true if this level's value is less than or equal to the other's.

### operator ==(Object other) → bool
The equality operator. Returns true if the other object is equal to this one.

### operator >(Level other) → bool
Returns true if this level's value is greater than the other's.

### operator >=(Level other) → bool
Returns true if this level's value is greater than or equal to the other's.
```

--------------------------------

### Level properties

Source: https://pub.dev/documentation/logging/latest/logging/Level-class.html

Properties of the Level class: name, value, hashCode, and runtimeType.

```APIDOC
## Level Properties

### name
- **name** (String) - The name of the level.

### value
- **value** (int) - Unique value for this level. Used to order levels, so filtering can exclude messages whose level is under certain value.

### hashCode
- **hashCode** (int) - The hash code for this object.

### runtimeType
- **runtimeType** (Type) - A representation of the runtime type of the object.
```

--------------------------------

### log(Level logLevel, Object? message, [Object? error, StackTrace? stackTrace, Zone? zone])

Source: https://pub.dev/documentation/logging/latest/logging/Logger-class.html

Adds a log record for a message at a particular log level if the level is loggable.

```APIDOC
## log(Level logLevel, Object? message, [Object? error, StackTrace? stackTrace, Zone? zone])

### Description
Adds a log record for a `message` at a particular `logLevel` if `isLoggable(logLevel)` is true.

### Method
log(Level logLevel, Object? message, [Object? error, StackTrace? stackTrace, Zone? zone])

### Parameters
- **logLevel** (Level) - Required - The level at which to log the message.
- **message** (Object?) - Required - The message to log.
- **error** (Object?) - Optional - An error object associated with the log.
- **stackTrace** (StackTrace?) - Optional - The stack trace associated with the log.
- **zone** (Zone?) - Optional - The zone in which the log is recorded.

### Returns
void
```

--------------------------------

### defaultLevel constant implementation

Source: https://pub.dev/documentation/logging/latest/logging/defaultLevel-constant.html

The defaultLevel constant is defined as Level.INFO, serving as the default logging level.

```dart
const defaultLevel = Level.INFO;
```

--------------------------------

### Logger.detached(String name)

Source: https://pub.dev/documentation/logging/latest/logging/Logger-class.html

Factory constructor that creates a new detached Logger with the given name.

```APIDOC
## Logger.detached(String name)

### Description
Creates a new detached Logger. A detached logger is not part of the logger hierarchy.

### Constructor
Logger.detached(String name)

### Parameters
- **name** (String) - Required - The name of the detached logger.

### Returns
A new detached Logger instance.
```

--------------------------------

### Listen for level changes

Source: https://pub.dev/documentation/logging/latest/index.html

Subscribes to the onLevelChanged stream to receive notifications when the logger level is updated.

```dart
Logger.root.onLevelChanged.listen((level) {
  print('The new log level is $level');
});
```

--------------------------------

### recordStackTraceAtLevel property

Source: https://pub.dev/documentation/logging/latest/logging/recordStackTraceAtLevel.html

Getter/setter pair for the recordStackTraceAtLevel property. It controls automatic stack trace recording for log messages at or above the specified level. The default value is Level.OFF.

```APIDOC
## recordStackTraceAtLevel property

### Description
Getter/setter pair for the recordStackTraceAtLevel property. It automatically records stack traces for any message at or above the specified level. This feature is off by default because it is expensive.

### Type
Level

### Default Value
Level.OFF

### Implementation
```
Level recordStackTraceAtLevel = Level.OFF;
```
```

--------------------------------

### LogRecord properties

Source: https://pub.dev/documentation/logging/latest/logging/LogRecord-class.html

Properties of LogRecord that provide access to the log entry details such as level, message, logger name, error, stack trace, zone, object, sequence number, and time.

```APIDOC
## LogRecord Properties

### error → Object?
Associated error (if any) when recording error messages. (final)

### level → Level
The severity level of the log record. (final)

### loggerName → String
The name of the logger where this record is stored. (final)

### message → String
The log message. (final)

### object → Object?
Non-string message passed to the logger. (final)

### sequenceNumber → int
Unique sequence number greater than all log records created before it. (final)

### stackTrace → StackTrace?
Associated stack trace (if any) when recording error messages. (final)

### time → DateTime
Time when this record was created. (final)

### zone → Zone?
Zone of the calling code which resulted in this LogRecord. (final)
```

--------------------------------

### Log complex messages with closures

Source: https://pub.dev/documentation/logging/latest/index.html

Uses a closure to defer message evaluation until the log level is confirmed to be active.

```dart
log.fine(() => [1, 2, 3, 4, 5].map((e) => e * 4).join("-"));
```

--------------------------------

### isLoggable(Level value)

Source: https://pub.dev/documentation/logging/latest/logging/Logger-class.html

Checks whether a message at the given level is loggable in this logger.

```APIDOC
## isLoggable(Level value)

### Description
Whether a message for `value`'s level is loggable in this logger.

### Method
isLoggable(Level value)

### Parameters
- **value** (Level) - Required - The level to check.

### Returns
bool - True if a message at the given level is loggable, false otherwise.
```

--------------------------------

### Log messages with async results

Source: https://pub.dev/documentation/logging/latest/index.html

Logs debug messages and errors within asynchronous operations.

```dart
var future = doSomethingAsync().then((result) {
  log.fine('Got the result: $result');
  processResult(result);
}).catchError((e, stackTrace) => log.severe('Oh noes!', e, stackTrace));
```

--------------------------------

### clearListeners()

Source: https://pub.dev/documentation/logging/latest/logging/Logger-class.html

Clears all listeners attached to this logger.

```APIDOC
## clearListeners()

### Description
Clears all listeners on this logger.

### Method
clearListeners()

### Returns
void
```

--------------------------------

### Set hierarchicalLoggingEnabled default value

Source: https://pub.dev/documentation/logging/latest/logging/hierarchicalLoggingEnabled.html

The default implementation of the hierarchicalLoggingEnabled property.

```dart
bool hierarchicalLoggingEnabled = false;
```
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