Classes

A LogFormatter configured to be ideal for writing human-readable log files.

By default, this formatter:

• Uses .default as the TimestampStyle
• Uses a custom SeverityStyle that pads the capitalized severity name
• Uses .hex as the CallingThreadStyle
• Uses default field separator delimiters
• Outputs the source code filename and line number of the call site

Each of these settings can be overridden during instantiation.

A LogFormatter that outputs Xcode-bound trace information for each LogEntry that has a Payload of .trace.

A LogConfiguration optimized for use when running within Xcode.

A LogRecorder implementation that maintains a set of daily rotating log files, kept for a user-specified number of days.

The StandardOutputLogRecorder is an OutputStreamLogRecorder that writes log messages to the standard output stream (`stdout`) of the running process.

A LogConfiguration that uses an underlying RotatingLogFileRecorder to maintain a directory of log files that are rotated on a daily basis.

The OutputStreamLogRecorder logs messages by writing to the standard output stream of the running process.

In case the name didn’t give it away, the BasicLogConfiguration class provides a basic implementation of the LogConfiguration protocol.

The BufferedLogRecorder is a generic LogRecorder that buffers the log messages passed to its record() function.

Construction requires a createBufferItem function, which is responsible for converting the LogEntry and formatted message String into the generic BufferItem type.

Three specific subclasses are also provided which will buffer a different BufferItem type for each call to record():

• BufferedMessageRecorder stores Strings containing the formatted log message.
• BufferedLogEntryRecorder stores the LogEntry values passed to record().
• BufferedLogEntryMessageRecorder stores a (LogEntry, String) tuple containing the LogEntry and formatted log message.

The BufferedMessageRecorder buffers the formatted log messages passed to its record() function.

The BufferedLogEntryRecorder buffers each LogEntry passed to its record() function.

The BufferedLogEntryMessageRecorder buffers each LogEntry and formatted message passed to its record() function.

A LogRecorder implementation that appends log entries to a file.

The FieldBasedLogFormatter provides a simple interface for constructing a customized LogFormatter by specifying different fields.

Let’s say you wanted to construct a LogFormatter that outputs the following fields separated by tabs:

• The LogEntry‘s timestamp property as a UNIX time value
• The severity of the LogEntry as a numeric value
• The Payload of the LogEntry

You could do this by constructing a FieldBasedLogFormatter as follows:

let formatter = FieldBasedLogFormatter(fields: [.timestamp(.unix),
                                                .delimiter(.tab),
                                                .severity(.numeric),
                                                .delimiter(.tab),
                                                .payload])

LogReceptacles provide the low-level interface for accepting log messages.

Although you could use a LogReceptacle directly to perform all logging functions, the Log implementation provides a higher-level interface that’s more convenient to use within your code.

The ConcatenatingLogFormatter lets you combine the output of multiple LogFormatters by concatenating their output and returning the result.

A standard LogConfiguration that, by default, uses the os_log() function (via the OSLogRecorder), which is only available as of iOS 10.0, macOS 10.12, tvOS 10.0, and watchOS 3.0.

If os_log() is not available, or if the StandardLogConfiguration is configured to bypass it, log messages will be written to either the stdout or stderr output stream of the running process.

The StandardStreamsLogRecorder is a LogRecorder that writes log messages to either the standard output stream (`stdout`) or the standard error stream (`stderr`) of the running process.

Messages are directed to the appropriate stream depending on the severity property of the LogEntry being recorded.

Messages having a severity of .verbose, .debug and .info will be directed to stdout, while those with a severity of .warning and .error are directed to stderr.

A partial implementation of the LogRecorder protocol.

The StandardErrorLogRecorder is an OutputStreamLogRecorder that writes log messages to the standard error stream (`stderr`) of the running process.

A standard LogFormatter that provides some common customization points.

A LogFormatter configured to be ideal for writing machine-parsable log files.

By default, this formatter:

• Uses .unix as the TimestampStyle
• Uses .numeric as the SeverityStyle
• Uses .hex as the CallingThreadStyle
• Uses .tab as the DelimiterStyle
• Outputs the source code filename and line number of the call site

Each of these settings can be overridden during instantiation.

A LogFormatter ideal for use within Xcode. This format is not well-suited for parsing.