[minor] Adds mechanism for having multiple logging targets

CHANGELOG.md

@@ -1,3 +1,7 @@
+## 3.3.0 - 2020-08-21
+
+- Adds helper methods to disable logging in production, and to configure multiple logging targets
+
 ## 3.2.0 - 2020-08-20
 
 - Enables SLF4J support on Android platform

README.md

@@ -223,5 +223,33 @@ implementation for each supported platform:
 ### Turn off logging in production
 
 ```kotlin
-Clog.configureLoggingInProduction(BuildConfig.DEBUG)
+val isDebug = ...
+Clog.configureLoggingInProduction(isDebug)
+```
+
+### Use a custom logger
+
+Replaces the current logging target with a custom one.
+
+```kotlin
+val customLogger = object : ClogLogger {
+    override fun log(priority: Clog.Priority, tag: String?, message: String) {
+        ...
+    }
+}
+Clog.updateProfile { it.copy(logger = customLogger) }
+```
+
+### Using multiple logging targets
+
+Add an additional logger to the current instance. Calling `addLogger` multiple times will continue adding loggers, and
+messages will be delegated to all loggers.
+
+```kotlin
+val customLogger = object : ClogLogger {
+    override fun log(priority: Clog.Priority, tag: String?, message: String) {
+        ...
+    }
+}
+Clog.addLogger(customLogger)
 ```

core/build.gradle.kts

@@ -139,7 +139,7 @@ publishing {
                 password = ghToken
             }
         }
-        maven(url = "https://api.bintray.com/maven/javaeden/Eden/Clog/;publish=1;override=1;") {
+        maven(url = "https://api.bintray.com/maven/cjbrooks12/maven/clog/;publish=1;override=1;") {
             name = "Bintray"
             credentials {
                 username = bintrayUser

core/src/commonMain/kotlin/dsl/dsl.kt

@@ -2,8 +2,10 @@
 package clog.dsl
 
 import clog.Clog
+import clog.api.ClogLogger
 import clog.api.ClogMessageFormatter
 import clog.api.ClogProfile
+import clog.impl.DelegatingLogger
 import clog.impl.DisableInProductionFilter
 
 // Logging DSL
@@ -95,3 +97,13 @@ inline fun Clog.configureLoggingInProduction(isDebug: Boolean) {
         it.copy(filter = DisableInProductionFilter(isDebug, it.filter))
     }
 }
+
+/**
+ * Adds an additional [ClogLogger] as a logging target.
+ */
+inline fun Clog.addLogger(logger: ClogLogger) {
+    updateProfile {
+        val delegatingLogger = it.logger as? DelegatingLogger ?: DelegatingLogger(listOf(it.logger))
+        it.copy(logger = delegatingLogger + logger)
+    }
+}

core/src/commonMain/kotlin/impl/DelegatingLogger.kt

@@ -0,0 +1,24 @@
+package clog.impl
+
+import clog.Clog
+import clog.api.ClogLogger
+
+/**
+ * Passes a log message to multiple other loggers
+ */
+data class DelegatingLogger(
+    val delegates: List<ClogLogger> = emptyList()
+) : ClogLogger {
+    override fun log(priority: Clog.Priority, tag: String?, message: String) {
+        delegates.forEach { it.log(priority, tag, message) }
+    }
+
+    /**
+     * Returns a copy of this [DelegatingLogger] with [logger] appended to its list of [delegates].
+     */
+    operator fun plus(logger: ClogLogger): DelegatingLogger {
+        return DelegatingLogger(
+            delegates + logger
+        )
+    }
+}

core/src/commonTest/kotlin/ClogSingletonTest.kt

@@ -1,6 +1,8 @@
 package clog
 
+import clog.dsl.addLogger
 import clog.dsl.configureLoggingInProduction
+import clog.impl.TestLogger
 import clog.impl.clogTest
 import kotlin.test.Test
 import kotlin.test.assertEquals
@@ -100,7 +102,8 @@ class ClogSingletonTest {
     @Test
     fun testLogInProductionFilter_notProd() {
         clogTest { logger ->
-            Clog.configureLoggingInProduction(false)
+            val isDebug = true
+            Clog.configureLoggingInProduction(isDebug)
 
             Clog.v("m1")
             assertTrue(logger.messageWasLogged)
@@ -113,7 +116,8 @@ class ClogSingletonTest {
     @Test
     fun testLogInProductionFilter_prod() {
         clogTest { logger ->
-            Clog.configureLoggingInProduction(true)
+            val isDebug = false
+            Clog.configureLoggingInProduction(isDebug)
 
             Clog.v("m1")
             assertFalse(logger.messageWasLogged)
@@ -122,4 +126,25 @@ class ClogSingletonTest {
             assertFalse(logger.messageWasLogged)
         }
     }
+
+    @Test
+    fun testAddLogger() {
+        clogTest { logger ->
+            val logger1 = TestLogger()
+            val logger2 = TestLogger()
+
+            Clog.addLogger(logger1)
+            Clog.addLogger(logger2)
+
+            Clog.v("m1")
+            assertTrue(logger.messageWasLogged)
+            assertTrue(logger1.messageWasLogged)
+            assertTrue(logger2.messageWasLogged)
+
+            Clog.e("m2")
+            assertTrue(logger.messageWasLogged)
+            assertTrue(logger1.messageWasLogged)
+            assertTrue(logger2.messageWasLogged)
+        }
+    }
 }