DailyLog

A lightweight Kotlin Multiplatform logging library with tag support and platform-specific formatting.

Features

• Multiplatform — Android, iOS, macOS, JVM
• Singleton — single DailyLogger object, ready to use anywhere
• Short API — d(), i(), w(), e()
• Tag support — default tag + per-message override
• Prefix — optional global prefix: [prefix/tag]
• Message prefix — optional per-message prefix: messagePrefix: message
• Log level filtering — DEBUG, INFO, WARNING, ERROR
• Platform-native output:
  • Android — android.util.Log
  • iOS / macOS — NSLog with heart emojis: 🤍 DEBUG, 💙 INFO, 💛 WARNING, ❤️ ERROR
  • JVM — stdout / stderr
• Zero dependencies — pure Kotlin, no third-party libs

Installation

Kotlin Multiplatform

kotlin {
    sourceSets {
        commonMain.dependencies {
            implementation("pro.dailycode:dailylog:<version>")
        }
    }
}

Android / JVM

dependencies {
    implementation("pro.dailycode:dailylog:<version>")
}

Quick Start

import pro.dailycode.dailylog.DailyLogger
import pro.dailycode.dailylog.LogLevel

DailyLogger.d("Preparing request")
DailyLogger.i("GET /api/users -> 200 OK")
DailyLogger.w("Slow response: 3200ms")
DailyLogger.e("Connection timeout")

Configuration

// Set default tag (used when no tag is passed)
DailyLogger.tag = "MyApp"

// Set optional global prefix — output: [MyApp/tag]
DailyLogger.prefix = "MyApp"

// Set minimum log level
DailyLogger.minLevel = LogLevel.WARNING

Tag Override

Pass a tag to override the default per message:

DailyLogger.tag = "App"

// Uses default tag "App"
DailyLogger.i("Starting up")

// Override tag per message
DailyLogger.i("Connected", tag = "Database")
DailyLogger.e("Cache miss", tag = "Cache")

Prefix

Set a global prefix to group logs: output becomes [prefix/tag].

DailyLogger.prefix = "MyApp"
DailyLogger.tag = "Network"

DailyLogger.i("Request sent")
// JVM output: INFO [MyApp/Network] Request sent

DailyLogger.e("Timeout", tag = "Database")
// JVM output: ERROR [MyApp/Database] Timeout

When prefix is null or empty, the format is [tag] as usual.

Message Prefix

Add a per-message prefix with messagePrefix — prepended to the message as messagePrefix: message:

DailyLogger.d("Connecting to db", messagePrefix = "Init")
// JVM output: DEBUG [App] Init: Connecting to db

DailyLogger.e("Table not found", tag = "Database", messagePrefix = "SQL")
// JVM output: ERROR [Database] SQL: Table not found

Log Level Filtering

Set a minimum log level to suppress less severe messages:

DailyLogger.minLevel = LogLevel.WARNING

DailyLogger.d("ignored")  // not printed
DailyLogger.i("ignored")  // not printed
DailyLogger.w("printed")  // printed
DailyLogger.e("printed")  // printed

Platform Output Examples

Android

D/Network: GET /api/users -> 200 OK
W/Network: Slow response: 3200ms
E/Network: Connection timeout

iOS

🤍 [Network] Preparing request
💙 [Network] GET /api/users -> 200 OK
💛 [Network] Slow response: 3200ms
❤️ [Network] Connection timeout

JVM

DEBUG [Network] Preparing request
INFO [Network] GET /api/users -> 200 OK
WARN [Network] Slow response: 3200ms
ERROR [Network] Connection timeout

API Reference

Method	Level
d(message, tag?, messagePrefix?)	DEBUG
i(message, tag?, messagePrefix?)	INFO
w(message, tag?, messagePrefix?)	WARNING
e(message, tag?, messagePrefix?)	ERROR
log(level, message, tag?, messagePrefix?)	any

Property	Type	Default	Description
tag	String	"DailyLogger"	Default tag
prefix	String?	null	Global prefix: [prefix/tag]
minLevel	LogLevel	DEBUG	Minimum log level

Compatibility

Platform	Min Version
Android	API 24
iOS	15.0
macOS	11.0
JVM	11

License

Copyright 2025 DailyCode

Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at

    http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.

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