JBLog

JBLog is a log output library for use in Swift project.

Using JBLog can easily log output like print() or NSLog(). Can easily change the level of the log to be outpu by using the JBLog.Level. Also can easily change the output of additional information(date, file name, line of code, function name, etc).

Install

CocoaPods

Add the following items to the CocoaPods dependency management file(Podfile).

source 'https://github.com/CocoaPods/Specs.git'
platform :ios, '9.0'

target '<YourProjectName>' do
  pod 'JBLog', '~> 1.0.0'
end

If already managing dependencies using Podfile, only need to add the JBLog dependency.

pod 'JBLog', '~> 1.0.0'

If added the dependency to Podfile, install the JBLog library by running the following command.

$ pod install

For details of the installation and usage of CocoaPods, visit official web site.

Carthage

Add the following entry to the Carthage dependency management file(Cartfile).

github "bokjaeo/JBLog" ~> 1.0.0

If added the dependency to Cartfile, install the JBLog library by running the following command.

$ carthage update

For details of the installation and usage of Carthage, visit official web site.

Swift Package Manager

Add the following entry to the package dependency file(Package.swift).

.package(url: "https://github.com/bokjaeo/JBLog.git", from: "1.0.0")

If added the dependency to Package.swift, install the JBLog library by running the following command.

$ swift build

For details of the installation and usage of Swift Package Manager, visit official web site.

Basic usage

Add the JBLog module to the file that will use the log output.

import JBLog

Create the JBLog instance object and output the log.

let log = JBLog()
log.warn("Warning message")

Recommended method

It is recommended that you declare and use global constants for the JBLog instance object in the project's app delegate object(AppDelegate) or in the global file.

import UIKit
import JBLog

let log = JBLog()

@UIApplicationMain
class AppDelegate: UIResponder, UIApplicationDelegate {

  var window: UIWindow?

  func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplicationLaunchOptionsKey: Any]? ) -> Bool {
    log.warn("Warning message")

    someMethod()

    return true
  }

  func someMethod() {
    log.error("Error message")
  }

  //... The rest is omitted ...

}

When executing the above code, the following log is output to the console.

[Warning] > Warning message
[Error] > Error message

Log level

The output of the log message may vary depending on the setting of the JBLog instance object. Whether or not to log is determined by the log level(JBLog.Level).

Available log levels

Setting the log level

The log level of the JBLog instance object can be set with the level property. Below is an example of setting all logs to be output.

let log = JBLog()
log.level = .verbose

Can set a different log level for each instance object.

let log1 = JBLog()
log1.level = .verbose

let log2 = JBLog()
log2.level = .warn

To set different log levels in the development environment and deployment environment, can set different log levels based on the DEBUG=1 macro in Preprocessor Macros.

let log = JBLog()
#if DEBUG
  log.level = .verbose
#else
  log.level = .warn
#endif

If not specify the log level, it defaults to warn.

Log output

The log output can be output using the log output methods of the JBLog instance object.

Error log output

The error log is always output if the log level is not none.

let log = JBLog()
log.error("Error message")

Warning log ouput

The warning log is output when the log level is set to verbose, debug, info, or warn.

let log = JBLog()
log.warn("Warning message")

Information log output

The information log is output when the log level is set to verbose, debug, or info.

let log = JBLog()
log.level = .info
log.info("Information message")

Debug log output

The debug log is output when the log level is set to verbose or debug.

let log = JBLog()
log.level = .debug
log.debug("Debug message")

Detail log output

The verbose log is output only when the log level is set to verbose.

let log = JBLog()
log.level = .verbose
log.verbose("Detail message")