Create MosaicLogger for output logs to another terminal or file

Solution for #494

CHANGELOG.md

@@ -7,6 +7,7 @@ New:
 - Create `mosaic-animation` library, that provides various possibilities for animating Mosaic. An analog of [androidx.compose.animation-core](https://developer.android.com/reference/kotlin/androidx/compose/animation/core/package-summary).
 - Add `IntrinsicSize` and related `Modifier.width/height/requiredWidth/requiredHeight`.
 - New `mosaic-testing` artifact for testing Mosaic.
+- Create [MosaicLogger] that can be used for output logs to another terminal or file.
 
 Changed:
 - Rendering now occurs as fast as possible, although still only when necessary. Previously the maximum FPS was capped to 20 which could cause minor visual delays when processing events.

mosaic-runtime/api/mosaic-runtime.api

@@ -16,6 +16,29 @@ public final class com/jakewharton/mosaic/MosaicKt {
 	public static final fun runMosaicBlocking (Lkotlin/jvm/functions/Function2;)V
 }
 
+public final class com/jakewharton/mosaic/MosaicLogLevel : java/lang/Enum {
+	public static final field DEBUG Lcom/jakewharton/mosaic/MosaicLogLevel;
+	public static final field VERBOSE Lcom/jakewharton/mosaic/MosaicLogLevel;
+	public static fun getEntries ()Lkotlin/enums/EnumEntries;
+	public static fun valueOf (Ljava/lang/String;)Lcom/jakewharton/mosaic/MosaicLogLevel;
+	public static fun values ()[Lcom/jakewharton/mosaic/MosaicLogLevel;
+}
+
+public abstract interface class com/jakewharton/mosaic/MosaicLogWriter {
+	public abstract fun close ()V
+	public abstract fun writeLine (Ljava/lang/String;)V
+}
+
+public final class com/jakewharton/mosaic/MosaicLogger {
+	public static final field $stable I
+	public static final field INSTANCE Lcom/jakewharton/mosaic/MosaicLogger;
+	public static field logLevel Lcom/jakewharton/mosaic/MosaicLogLevel;
+	public static field logWriter Lcom/jakewharton/mosaic/MosaicLogWriter;
+	public final fun d (Lkotlin/jvm/functions/Function0;)V
+	public final fun log (Lcom/jakewharton/mosaic/MosaicLogLevel;Lkotlin/jvm/functions/Function0;)V
+	public final fun v (Lkotlin/jvm/functions/Function0;)V
+}
+
 public final class com/jakewharton/mosaic/Terminal {
 	public static final field $stable I
 	public synthetic fun <init> (JLkotlin/jvm/internal/DefaultConstructorMarker;)V

mosaic-runtime/api/mosaic-runtime.klib.api

@@ -38,6 +38,17 @@ final enum class com.jakewharton.mosaic.ui/AnsiLevel : kotlin/Enum<com.jakewhart
     final fun values(): kotlin/Array<com.jakewharton.mosaic.ui/AnsiLevel> // com.jakewharton.mosaic.ui/AnsiLevel.values|values#static(){}[0]
 }
 
+final enum class com.jakewharton.mosaic/MosaicLogLevel : kotlin/Enum<com.jakewharton.mosaic/MosaicLogLevel> { // com.jakewharton.mosaic/MosaicLogLevel|null[0]
+    enum entry DEBUG // com.jakewharton.mosaic/MosaicLogLevel.DEBUG|null[0]
+    enum entry VERBOSE // com.jakewharton.mosaic/MosaicLogLevel.VERBOSE|null[0]
+
+    final val entries // com.jakewharton.mosaic/MosaicLogLevel.entries|#static{}entries[0]
+        final fun <get-entries>(): kotlin.enums/EnumEntries<com.jakewharton.mosaic/MosaicLogLevel> // com.jakewharton.mosaic/MosaicLogLevel.entries.<get-entries>|<get-entries>#static(){}[0]
+
+    final fun valueOf(kotlin/String): com.jakewharton.mosaic/MosaicLogLevel // com.jakewharton.mosaic/MosaicLogLevel.valueOf|valueOf#static(kotlin.String){}[0]
+    final fun values(): kotlin/Array<com.jakewharton.mosaic/MosaicLogLevel> // com.jakewharton.mosaic/MosaicLogLevel.values|values#static(){}[0]
+}
+
 abstract fun interface com.jakewharton.mosaic.layout/MeasurePolicy { // com.jakewharton.mosaic.layout/MeasurePolicy|null[0]
     abstract fun (com.jakewharton.mosaic.layout/MeasureScope).measure(kotlin.collections/List<com.jakewharton.mosaic.layout/Measurable>, com.jakewharton.mosaic.ui.unit/Constraints): com.jakewharton.mosaic.layout/MeasureResult // com.jakewharton.mosaic.layout/MeasurePolicy.measure|[email protected](kotlin.collections.List<com.jakewharton.mosaic.layout.Measurable>;com.jakewharton.mosaic.ui.unit.Constraints){}[0]
     open fun maxIntrinsicHeight(kotlin.collections/List<com.jakewharton.mosaic.layout/IntrinsicMeasurable>, kotlin/Int): kotlin/Int // com.jakewharton.mosaic.layout/MeasurePolicy.maxIntrinsicHeight|maxIntrinsicHeight(kotlin.collections.List<com.jakewharton.mosaic.layout.IntrinsicMeasurable>;kotlin.Int){}[0]
@@ -209,6 +220,11 @@ abstract interface com.jakewharton.mosaic/Mosaic { // com.jakewharton.mosaic/Mos
     abstract suspend fun awaitComplete() // com.jakewharton.mosaic/Mosaic.awaitComplete|awaitComplete(){}[0]
 }
 
+abstract interface com.jakewharton.mosaic/MosaicLogWriter { // com.jakewharton.mosaic/MosaicLogWriter|null[0]
+    abstract fun close() // com.jakewharton.mosaic/MosaicLogWriter.close|close(){}[0]
+    abstract fun writeLine(kotlin/String) // com.jakewharton.mosaic/MosaicLogWriter.writeLine|writeLine(kotlin.String){}[0]
+}
+
 abstract interface com.jakewharton.mosaic/TextCanvas { // com.jakewharton.mosaic/TextCanvas|null[0]
     abstract val height // com.jakewharton.mosaic/TextCanvas.height|{}height[0]
         abstract fun <get-height>(): kotlin/Int // com.jakewharton.mosaic/TextCanvas.height.<get-height>|<get-height>(){}[0]
@@ -625,6 +641,19 @@ final object com.jakewharton.mosaic.ui/Arrangement { // com.jakewharton.mosaic.u
     }
 }
 
+final object com.jakewharton.mosaic/MosaicLogger { // com.jakewharton.mosaic/MosaicLogger|null[0]
+    final var logLevel // com.jakewharton.mosaic/MosaicLogger.logLevel|{}logLevel[0]
+        final fun <get-logLevel>(): com.jakewharton.mosaic/MosaicLogLevel // com.jakewharton.mosaic/MosaicLogger.logLevel.<get-logLevel>|<get-logLevel>(){}[0]
+        final fun <set-logLevel>(com.jakewharton.mosaic/MosaicLogLevel) // com.jakewharton.mosaic/MosaicLogger.logLevel.<set-logLevel>|<set-logLevel>(com.jakewharton.mosaic.MosaicLogLevel){}[0]
+    final var logWriter // com.jakewharton.mosaic/MosaicLogger.logWriter|{}logWriter[0]
+        final fun <get-logWriter>(): com.jakewharton.mosaic/MosaicLogWriter? // com.jakewharton.mosaic/MosaicLogger.logWriter.<get-logWriter>|<get-logWriter>(){}[0]
+        final fun <set-logWriter>(com.jakewharton.mosaic/MosaicLogWriter?) // com.jakewharton.mosaic/MosaicLogger.logWriter.<set-logWriter>|<set-logWriter>(com.jakewharton.mosaic.MosaicLogWriter?){}[0]
+
+    final inline fun d(kotlin/Function0<kotlin/String>) // com.jakewharton.mosaic/MosaicLogger.d|d(kotlin.Function0<kotlin.String>){}[0]
+    final inline fun log(com.jakewharton.mosaic/MosaicLogLevel, kotlin/Function0<kotlin/String>) // com.jakewharton.mosaic/MosaicLogger.log|log(com.jakewharton.mosaic.MosaicLogLevel;kotlin.Function0<kotlin.String>){}[0]
+    final inline fun v(kotlin/Function0<kotlin/String>) // com.jakewharton.mosaic/MosaicLogger.v|v(kotlin.Function0<kotlin.String>){}[0]
+}
+
 final const val com.jakewharton.mosaic.ui/EmptyTextStyle // com.jakewharton.mosaic.ui/EmptyTextStyle|{}EmptyTextStyle[0]
     final fun <get-EmptyTextStyle>(): kotlin/Int // com.jakewharton.mosaic.ui/EmptyTextStyle.<get-EmptyTextStyle>|<get-EmptyTextStyle>(){}[0]
 final const val com.jakewharton.mosaic.ui/UnspecifiedColor // com.jakewharton.mosaic.ui/UnspecifiedColor|{}UnspecifiedColor[0]
@@ -686,6 +715,7 @@ final val com.jakewharton.mosaic/com_jakewharton_mosaic_AnsiRendering$stableprop
 final val com.jakewharton.mosaic/com_jakewharton_mosaic_DebugRendering$stableprop // com.jakewharton.mosaic/com_jakewharton_mosaic_DebugRendering$stableprop|#static{}com_jakewharton_mosaic_DebugRendering$stableprop[0]
 final val com.jakewharton.mosaic/com_jakewharton_mosaic_GlobalSnapshotManager$stableprop // com.jakewharton.mosaic/com_jakewharton_mosaic_GlobalSnapshotManager$stableprop|#static{}com_jakewharton_mosaic_GlobalSnapshotManager$stableprop[0]
 final val com.jakewharton.mosaic/com_jakewharton_mosaic_MosaicComposition$stableprop // com.jakewharton.mosaic/com_jakewharton_mosaic_MosaicComposition$stableprop|#static{}com_jakewharton_mosaic_MosaicComposition$stableprop[0]
+final val com.jakewharton.mosaic/com_jakewharton_mosaic_MosaicLogger$stableprop // com.jakewharton.mosaic/com_jakewharton_mosaic_MosaicLogger$stableprop|#static{}com_jakewharton_mosaic_MosaicLogger$stableprop[0]
 final val com.jakewharton.mosaic/com_jakewharton_mosaic_MosaicNodeApplier$stableprop // com.jakewharton.mosaic/com_jakewharton_mosaic_MosaicNodeApplier$stableprop|#static{}com_jakewharton_mosaic_MosaicNodeApplier$stableprop[0]
 final val com.jakewharton.mosaic/com_jakewharton_mosaic_Terminal$stableprop // com.jakewharton.mosaic/com_jakewharton_mosaic_Terminal$stableprop|#static{}com_jakewharton_mosaic_Terminal$stableprop[0]
 final val com.jakewharton.mosaic/com_jakewharton_mosaic_TextPixel$stableprop // com.jakewharton.mosaic/com_jakewharton_mosaic_TextPixel$stableprop|#static{}com_jakewharton_mosaic_TextPixel$stableprop[0]
@@ -793,6 +823,7 @@ final fun com.jakewharton.mosaic/com_jakewharton_mosaic_AnsiRendering$stableprop
 final fun com.jakewharton.mosaic/com_jakewharton_mosaic_DebugRendering$stableprop_getter(): kotlin/Int // com.jakewharton.mosaic/com_jakewharton_mosaic_DebugRendering$stableprop_getter|com_jakewharton_mosaic_DebugRendering$stableprop_getter(){}[0]
 final fun com.jakewharton.mosaic/com_jakewharton_mosaic_GlobalSnapshotManager$stableprop_getter(): kotlin/Int // com.jakewharton.mosaic/com_jakewharton_mosaic_GlobalSnapshotManager$stableprop_getter|com_jakewharton_mosaic_GlobalSnapshotManager$stableprop_getter(){}[0]
 final fun com.jakewharton.mosaic/com_jakewharton_mosaic_MosaicComposition$stableprop_getter(): kotlin/Int // com.jakewharton.mosaic/com_jakewharton_mosaic_MosaicComposition$stableprop_getter|com_jakewharton_mosaic_MosaicComposition$stableprop_getter(){}[0]
+final fun com.jakewharton.mosaic/com_jakewharton_mosaic_MosaicLogger$stableprop_getter(): kotlin/Int // com.jakewharton.mosaic/com_jakewharton_mosaic_MosaicLogger$stableprop_getter|com_jakewharton_mosaic_MosaicLogger$stableprop_getter(){}[0]
 final fun com.jakewharton.mosaic/com_jakewharton_mosaic_MosaicNodeApplier$stableprop_getter(): kotlin/Int // com.jakewharton.mosaic/com_jakewharton_mosaic_MosaicNodeApplier$stableprop_getter|com_jakewharton_mosaic_MosaicNodeApplier$stableprop_getter(){}[0]
 final fun com.jakewharton.mosaic/com_jakewharton_mosaic_Terminal$stableprop_getter(): kotlin/Int // com.jakewharton.mosaic/com_jakewharton_mosaic_Terminal$stableprop_getter|com_jakewharton_mosaic_Terminal$stableprop_getter(){}[0]
 final fun com.jakewharton.mosaic/com_jakewharton_mosaic_TextPixel$stableprop_getter(): kotlin/Int // com.jakewharton.mosaic/com_jakewharton_mosaic_TextPixel$stableprop_getter|com_jakewharton_mosaic_TextPixel$stableprop_getter(){}[0]

mosaic-runtime/src/commonMain/kotlin/com/jakewharton/mosaic/logging.kt

@@ -0,0 +1,66 @@
+package com.jakewharton.mosaic
+
+import com.github.ajalt.mordant.platform.MultiplatformSystem
+import kotlin.jvm.JvmField
+
+private const val MOSAIC_LOG_PATH = "MOSAIC_LOG_PATH"
+private const val MOSAIC_LOG_LEVEL = "MOSAIC_LOG_LEVEL"
+
+public enum class MosaicLogLevel(internal val envVarValue: String) {
+	VERBOSE(envVarValue = "verbose"),
+	DEBUG(envVarValue = "debug"),
+}
+
+public object MosaicLogger {
+
+	@JvmField
+	@PublishedApi
+	internal var logWriter: MosaicLogWriter? = null
+
+	@JvmField
+	@PublishedApi
+	internal var logLevel: MosaicLogLevel = MosaicLogLevel.DEBUG
+
+	internal fun init() {
+		logWriter = getDefaultLogWriter()
+		logLevel = getDefaultLogLevel()
+	}
+
+	private fun getDefaultLogWriter(): MosaicLogWriter? {
+		val logPath = MultiplatformSystem.readEnvironmentVariable(MOSAIC_LOG_PATH)
+		if (logPath.isNullOrEmpty()) return null
+		return createDefaultLogWriter(logPath)
+	}
+
+	private fun getDefaultLogLevel(): MosaicLogLevel {
+		val logLevelValue = MultiplatformSystem.readEnvironmentVariable(MOSAIC_LOG_LEVEL)
+		return MosaicLogLevel.entries.find { it.envVarValue == logLevelValue }
+			?: MosaicLogLevel.DEBUG
+	}
+
+	internal fun finalize() {
+		logWriter?.let {
+			logWriter = null
+			it.close()
+		}
+	}
+
+	public inline fun log(level: MosaicLogLevel, message: () -> String) {
+		val logWriter = logWriter
+		if (logWriter != null && level >= logLevel) {
+			logWriter.writeLine(message())
+		}
+	}
+
+	public inline fun v(message: () -> String): Unit = log(MosaicLogLevel.VERBOSE, message)
+
+	public inline fun d(message: () -> String): Unit = log(MosaicLogLevel.DEBUG, message)
+}
+
+@PublishedApi
+internal interface MosaicLogWriter {
+	fun writeLine(message: String)
+	fun close()
+}
+
+internal expect fun createDefaultLogWriter(logPath: String): MosaicLogWriter?

mosaic-runtime/src/commonMain/kotlin/com/jakewharton/mosaic/mosaic.kt

@@ -67,6 +67,7 @@ public suspend fun runMosaic(content: @Composable () -> Unit) {
 }
 
 internal suspend fun runMosaic(enterRawMode: Boolean, content: @Composable () -> Unit) {
+	MosaicLogger.init()
 	val mordantTerminal = MordantTerminal()
 	val rendering = createRendering(mordantTerminal.terminalInfo.ansiLevel.toMosaicAnsiLevel())
 
@@ -83,6 +84,7 @@ internal suspend fun runMosaic(enterRawMode: Boolean, content: @Composable () ->
 		hook = {
 			platformDisplay(cursorShow)
 			rawMode?.close()
+			MosaicLogger.finalize()
 		},
 		block = {
 			val clock = BroadcastFrameClock()

mosaic-runtime/src/jvmMain/kotlin/com/jakewharton/mosaic/logging.jvm.kt

@@ -0,0 +1,25 @@
+package com.jakewharton.mosaic
+
+import java.io.Writer
+import java.nio.file.StandardOpenOption
+import kotlin.io.path.Path
+import kotlin.io.path.writer
+
+internal actual fun createDefaultLogWriter(logPath: String): MosaicLogWriter? {
+	return object : MosaicLogWriter {
+
+		private val writer: Writer = Path(logPath).writer(
+			options = arrayOf(StandardOpenOption.WRITE, StandardOpenOption.APPEND),
+		)
+
+		override fun writeLine(message: String) {
+			writer.write(message)
+			writer.write("\n")
+			writer.flush()
+		}
+
+		override fun close() {
+			writer.close()
+		}
+	}
+}

mosaic-runtime/src/linuxMain/kotlin/com/jakewharton/mosaic/logging.linux.kt

@@ -0,0 +1,10 @@
+package com.jakewharton.mosaic
+
+import kotlinx.cinterop.ExperimentalForeignApi
+import kotlinx.cinterop.cstr
+import platform.posix.write
+
+@OptIn(ExperimentalForeignApi::class)
+internal actual inline fun write(fileDescriptor: Int, str: String) {
+	write(fileDescriptor, str.cstr, str.length.toULong())
+}

mosaic-runtime/src/macosMain/kotlin/com/jakewharton/mosaic/logging.macos.kt

@@ -0,0 +1,10 @@
+package com.jakewharton.mosaic
+
+import kotlinx.cinterop.ExperimentalForeignApi
+import kotlinx.cinterop.cstr
+import platform.posix.write
+
+@OptIn(ExperimentalForeignApi::class)
+internal actual inline fun write(fileDescriptor: Int, str: String) {
+	write(fileDescriptor, str.cstr, str.length.toULong())
+}

mosaic-runtime/src/mingwMain/kotlin/com/jakewharton/mosaic/logging.mingw.kt

@@ -0,0 +1,10 @@
+package com.jakewharton.mosaic
+
+import kotlinx.cinterop.ExperimentalForeignApi
+import kotlinx.cinterop.cstr
+import platform.posix.write
+
+@OptIn(ExperimentalForeignApi::class)
+internal actual inline fun write(fileDescriptor: Int, str: String) {
+	write(fileDescriptor, str.cstr, str.length.toUInt())
+}

mosaic-runtime/src/nativeMain/kotlin/com/jakewharton/mosaic/logging.native.kt

@@ -0,0 +1,26 @@
+package com.jakewharton.mosaic
+
+import platform.posix.O_APPEND
+import platform.posix.O_WRONLY
+import platform.posix.close
+import platform.posix.open
+
+internal actual fun createDefaultLogWriter(logPath: String): MosaicLogWriter? {
+	val fileDescriptor = open(logPath, O_WRONLY or O_APPEND)
+	if (fileDescriptor < 0) {
+		return null
+	}
+	return object : MosaicLogWriter {
+
+		override fun writeLine(message: String) {
+			write(fileDescriptor, message)
+			write(fileDescriptor, "\n")
+		}
+
+		override fun close() {
+			close(fileDescriptor)
+		}
+	}
+}
+
+internal expect inline fun write(fileDescriptor: Int, str: String)