LoggerLogger

LoggerLogger is intented to be a simple, lightweight, and fast logging framework for Swift-based applications.

Installation

Carthage is the easiest way to use this framework. Follow the Carthage instructions to add a framework to your application. The proper declaration for your Cartfile is:

github "nebhale/LoggerLogger"

Usage

To use LoggerLogger, first start by importing the module. Next, create a new instance of the Logger type. In most cases, using the empty initializer is sufficient. This creates a Logger that uses the name of the file it is declared in, as its name. Finally, call the appropriate logging method (debug(), info(), warn(), error()). The logging methods ensure that all input, whether via an argument or a trailing closure, are lazily evaluated and if and only if logging should happen based on the configuration.

import LoggerLogger

final class Example {

    private let logger = Logger()

    func example() {
        logger.debug("debug autoclosure")
        logger.debug { "debug closure" }

        logger.info("info autoclosure")
        logger.info { "info closure" }

        logger.warn("warn autoclosure")
        logger.warn { "warn closure" }

        logger.error("error autoclosure")
        logger.error { "error closure" }
    }
}

Configuration

Configuration of LoggerLogger is done using a Logging.plist file, in the main bundle of the application. A logger can be configured with a Level and a Format.

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<plist version="1.0">
<dict>
  <key>Level</key>
  <string>Warn</string>
  <key>Format</key>
  <string>%level %message</string>
</dict>
</plist>

Levels

There are 4 levels that can be configured. The values are not case sensitive.

Value	Description
`Debug`	Indicates that a message is trivial. The lowest level severity.
`Info`	Indicates that a message is routine in normal operation
`Warn`	Indicates that a message is not routine in normal operation, but may not be a problem
`Error`	Indicates that a message is not routine in normal operation, and is a problem. The highest severity.

If not specified, the default Level if Info

Format

The format is a string containing a set of patterns that can be replaced. Any other characters in the format string are left unchanged.

Pattern	Description
`%column`	The column the message was generated at
`%date{<FORMAT>}`	The date the message was generated on. The format of the date (usable by `NSDateFormatter`) is specified within the curly braces.
`%file`	The file the message was generated in
`%function`	The function the message was generated in
`%level`	The level the message was logged at
`%line`	The line the message was generated at
`%message`	The logged message
`%thread`	Whether the message was logged on the main or background thread

If not specified the default Format is %date{HH:mm:ss} %level %message.

Named Loggers

In addition to the root Logger, additional named Loggers can be configured. In order to use a named Logger, the declaration is slightly different.

private let logger = Logger(name: "Networking")

In order to configure a named Logger, the same keys are used, they are instead nested under a dictionary who's key is the name of the Logger being configured.

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<plist version="1.0">
<dict>
  <key>Level</key>
  <string>Warn</string>
  <key>Neworking</key>
  <dict>
    <key>Level</key>
    <string>Error</string>
  </dict>
</dict>
</plist>

Contributing

Pull requests are welcome.

License

This project is released under version 2.0 of the Apache License.

nebhale / LoggerLogger