✨ Add @serialization support to PlatformFile

vinceglb · vinceglb · commit 3fc3343df01e · 2025-10-04T20:15:06.000+02:00
diff --git a/filekit-core/build.gradle.kts b/filekit-core/build.gradle.kts
@@ -4,6 +4,7 @@ import org.jetbrains.kotlin.gradle.dsl.JvmTarget
 plugins {
     alias(libs.plugins.androidLibrary)
     alias(libs.plugins.kotlinMultiplatform)
+    alias(libs.plugins.kotlinSerialization)
     alias(libs.plugins.vanniktech.mavenPublish)
 }
 
@@ -55,6 +56,9 @@ kotlin {
 
             // Kotlinx IO
             api(libs.kotlinx.io)
+
+            // Kotlinx Serialization
+            implementation(libs.kotlinx.serialization.core)
         }
 
         commonTest.dependencies {
@@ -69,6 +73,9 @@ kotlin {
             }
         }
         val nonWebTest by creating { dependsOn(commonTest.get()) }
+        nonWebTest.dependencies {
+            implementation(libs.kotlinx.serialization.json)
+        }
 
         val jvmAndNativeMain by creating { dependsOn(nonWebMain) }
 
diff --git a/filekit-core/src/androidMain/kotlin/io/github/vinceglb/filekit/PlatformFile.android.kt b/filekit-core/src/androidMain/kotlin/io/github/vinceglb/filekit/PlatformFile.android.kt
@@ -21,12 +21,14 @@ import kotlinx.io.asSink
 import kotlinx.io.asSource
 import kotlinx.io.files.Path
 import kotlinx.io.files.SystemFileSystem
+import kotlinx.serialization.Serializable
 import java.io.File
 import java.nio.file.Files
 import java.nio.file.attribute.BasicFileAttributes
 import kotlin.time.ExperimentalTime
 import kotlin.time.Instant
 
+@Serializable(with = PlatformFileSerializer::class)
 public actual data class PlatformFile(
     val androidFile: AndroidFile
 ) {
diff --git a/filekit-core/src/appleMain/kotlin/io/github/vinceglb/filekit/PlatformFile.apple.kt b/filekit-core/src/appleMain/kotlin/io/github/vinceglb/filekit/PlatformFile.apple.kt
@@ -23,6 +23,7 @@ import kotlinx.coroutines.IO
 import kotlinx.coroutines.withContext
 import kotlinx.io.files.Path
 import kotlinx.io.files.SystemFileSystem
+import kotlinx.serialization.Serializable
 import platform.CoreFoundation.CFRelease
 import platform.CoreFoundation.CFStringCreateWithCString
 import platform.CoreFoundation.CFStringGetCString
@@ -46,6 +47,7 @@ import platform.UniformTypeIdentifiers.UTType
 import kotlin.time.ExperimentalTime
 import kotlin.time.Instant
 
+@Serializable(with = PlatformFileSerializer::class)
 public actual data class PlatformFile(
     val nsUrl: NSURL,
 ) {
@@ -220,16 +222,6 @@ public actual suspend fun PlatformFile.bookmarkData(): BookmarkData = withContex
     }
 }
 
-internal actual suspend fun PlatformFile.prepareDestinationForWrite(
-    source: PlatformFile
-): PlatformFile = withScopedAccess {
-    if (isDirectory()) {
-        PlatformFile(toKotlinxIoPath() / source.name)
-    } else {
-        this
-    }
-}
-
 public actual fun PlatformFile.releaseBookmark() {}
 
 @OptIn(ExperimentalForeignApi::class, BetaInteropApi::class)
diff --git a/filekit-core/src/commonMain/kotlin/io/github/vinceglb/filekit/PlatformFile.kt b/filekit-core/src/commonMain/kotlin/io/github/vinceglb/filekit/PlatformFile.kt
@@ -1,7 +1,9 @@
 package io.github.vinceglb.filekit
 
 import io.github.vinceglb.filekit.mimeType.MimeType
+import kotlinx.serialization.Serializable
 
+@Serializable(with = PlatformFileSerializer::class)
 public expect class PlatformFile {
     override fun toString(): String
     public companion object
diff --git a/filekit-core/src/commonMain/kotlin/io/github/vinceglb/filekit/PlatformFileSerializer.kt b/filekit-core/src/commonMain/kotlin/io/github/vinceglb/filekit/PlatformFileSerializer.kt
@@ -0,0 +1,12 @@
+package io.github.vinceglb.filekit
+
+import kotlinx.serialization.KSerializer
+import kotlinx.serialization.descriptors.SerialDescriptor
+import kotlinx.serialization.encoding.Decoder
+import kotlinx.serialization.encoding.Encoder
+
+public expect object PlatformFileSerializer : KSerializer<PlatformFile> {
+    override val descriptor: SerialDescriptor
+    override fun serialize(encoder: Encoder, value: PlatformFile)
+    override fun deserialize(decoder: Decoder): PlatformFile
+}
diff --git a/filekit-core/src/jsMain/kotlin/io/github/vinceglb/filekit/PlatformFile.js.kt b/filekit-core/src/jsMain/kotlin/io/github/vinceglb/filekit/PlatformFile.js.kt
@@ -4,6 +4,7 @@ import io.github.vinceglb.filekit.exceptions.FileKitException
 import io.github.vinceglb.filekit.mimeType.MimeType
 import kotlinx.coroutines.Dispatchers
 import kotlinx.coroutines.withContext
+import kotlinx.serialization.Serializable
 import org.khronos.webgl.ArrayBuffer
 import org.khronos.webgl.Uint8Array
 import org.khronos.webgl.get
@@ -13,6 +14,7 @@ import kotlin.coroutines.resume
 import kotlin.coroutines.resumeWithException
 import kotlin.coroutines.suspendCoroutine
 
+@Serializable(with = PlatformFileSerializer::class)
 public actual data class PlatformFile(
     val file: File,
 ) {
@@ -70,4 +72,3 @@ public actual suspend fun PlatformFile.readBytes(): ByteArray = withContext(Disp
 public actual fun PlatformFile.mimeType(): MimeType? =
     takeIf { file.type.isNotBlank() }
         ?.let { MimeType.parse(file.type) }
-
diff --git a/filekit-core/src/jsMain/kotlin/io/github/vinceglb/filekit/PlatformFileSerializer.js.kt b/filekit-core/src/jsMain/kotlin/io/github/vinceglb/filekit/PlatformFileSerializer.js.kt
@@ -0,0 +1,25 @@
+package io.github.vinceglb.filekit
+
+import kotlinx.serialization.KSerializer
+import kotlinx.serialization.descriptors.PrimitiveKind
+import kotlinx.serialization.descriptors.PrimitiveSerialDescriptor
+import kotlinx.serialization.descriptors.SerialDescriptor
+import kotlinx.serialization.encoding.Decoder
+import kotlinx.serialization.encoding.Encoder
+
+private const val unsupportedMessage = "PlatformFile serialization is not supported on JS targets"
+
+public actual object PlatformFileSerializer : KSerializer<PlatformFile> {
+    actual override val descriptor: SerialDescriptor = PrimitiveSerialDescriptor(
+        serialName = "io.github.vinceglb.filekit.PlatformFile",
+        kind = PrimitiveKind.STRING
+    )
+
+    actual override fun deserialize(decoder: Decoder): PlatformFile {
+        error(unsupportedMessage)
+    }
+
+    actual override fun serialize(encoder: Encoder, value: PlatformFile) {
+        error(unsupportedMessage)
+    }
+}
diff --git a/filekit-core/src/jvmMain/kotlin/io/github/vinceglb/filekit/PlatformFile.jvm.kt b/filekit-core/src/jvmMain/kotlin/io/github/vinceglb/filekit/PlatformFile.jvm.kt
@@ -5,14 +5,16 @@ import io.github.vinceglb.filekit.utils.toFile
 import io.github.vinceglb.filekit.utils.toKotlinxIoPath
 import kotlinx.coroutines.Dispatchers
 import kotlinx.coroutines.withContext
-import kotlinx.io.files.Path
 import kotlinx.io.files.SystemFileSystem
+import kotlinx.io.files.Path
 import java.io.File
 import java.nio.file.Files
 import java.nio.file.attribute.BasicFileAttributes
 import kotlin.time.ExperimentalTime
 import kotlin.time.Instant
+import kotlinx.serialization.Serializable
 
+@Serializable(with = PlatformFileSerializer::class)
 public actual data class PlatformFile(
     val file: File,
 ) {
diff --git a/filekit-core/src/nonWebMain/kotlin/io/github/vinceglb/filekit/PlatformFileSerializer.nonWeb.kt b/filekit-core/src/nonWebMain/kotlin/io/github/vinceglb/filekit/PlatformFileSerializer.nonWeb.kt
@@ -0,0 +1,24 @@
+package io.github.vinceglb.filekit
+
+import kotlinx.serialization.KSerializer
+import kotlinx.serialization.descriptors.PrimitiveKind
+import kotlinx.serialization.descriptors.PrimitiveSerialDescriptor
+import kotlinx.serialization.descriptors.SerialDescriptor
+import kotlinx.serialization.encoding.Decoder
+import kotlinx.serialization.encoding.Encoder
+
+public actual object PlatformFileSerializer : KSerializer<PlatformFile> {
+    actual override val descriptor: SerialDescriptor = PrimitiveSerialDescriptor(
+        serialName = "io.github.vinceglb.filekit.PlatformFile",
+        kind = PrimitiveKind.STRING
+    )
+
+    actual override fun deserialize(decoder: Decoder): PlatformFile {
+        val path = decoder.decodeString()
+        return PlatformFile(path)
+    }
+
+    actual override fun serialize(encoder: Encoder, value: PlatformFile) {
+        encoder.encodeString(value.path)
+    }
+}
diff --git a/filekit-core/src/wasmJsMain/kotlin/io/github/vinceglb/filekit/PlatformFile.wasmJs.kt b/filekit-core/src/wasmJsMain/kotlin/io/github/vinceglb/filekit/PlatformFile.wasmJs.kt
@@ -4,6 +4,7 @@ import io.github.vinceglb.filekit.exceptions.FileKitException
 import io.github.vinceglb.filekit.mimeType.MimeType
 import kotlinx.coroutines.Dispatchers
 import kotlinx.coroutines.withContext
+import kotlinx.serialization.Serializable
 import org.khronos.webgl.ArrayBuffer
 import org.khronos.webgl.Uint8Array
 import org.khronos.webgl.get
@@ -13,6 +14,7 @@ import kotlin.coroutines.resume
 import kotlin.coroutines.resumeWithException
 import kotlin.coroutines.suspendCoroutine
 
+@Serializable(with = PlatformFileSerializer::class)
 public actual data class PlatformFile(
     val file: File,
 ) {
@@ -30,9 +32,11 @@ public actual val PlatformFile.extension: String
 public actual val PlatformFile.nameWithoutExtension: String
     get() = name.substringBeforeLast(".", name)
 
+@OptIn(ExperimentalWasmJsInterop::class)
 public actual fun PlatformFile.size(): Long =
     file.size.toDouble().toLong()
 
+@OptIn(ExperimentalWasmJsInterop::class)
 public actual suspend fun PlatformFile.readBytes(): ByteArray = withContext(Dispatchers.Main) {
     suspendCoroutine { continuation ->
         val reader = FileReader()
diff --git a/filekit-core/src/wasmJsMain/kotlin/io/github/vinceglb/filekit/PlatformFileSerializer.wasmJs.kt b/filekit-core/src/wasmJsMain/kotlin/io/github/vinceglb/filekit/PlatformFileSerializer.wasmJs.kt
@@ -0,0 +1,26 @@
+package io.github.vinceglb.filekit
+
+import kotlinx.serialization.KSerializer
+import kotlinx.serialization.descriptors.PrimitiveKind
+import kotlinx.serialization.descriptors.PrimitiveSerialDescriptor
+import kotlinx.serialization.descriptors.SerialDescriptor
+import kotlinx.serialization.encoding.Decoder
+import kotlinx.serialization.encoding.Encoder
+
+private const val unsupportedMessage =
+    "PlatformFile serialization is not supported on Wasm JS targets"
+
+public actual object PlatformFileSerializer : KSerializer<PlatformFile> {
+    actual override val descriptor: SerialDescriptor = PrimitiveSerialDescriptor(
+        serialName = "io.github.vinceglb.filekit.PlatformFile",
+        kind = PrimitiveKind.STRING
+    )
+
+    actual override fun deserialize(decoder: Decoder): PlatformFile {
+        error(unsupportedMessage)
+    }
+
+    actual override fun serialize(encoder: Encoder, value: PlatformFile) {
+        error(unsupportedMessage)
+    }
+}
diff --git a/gradle/libs.versions.toml b/gradle/libs.versions.toml
@@ -16,6 +16,7 @@ dbus-java = "5.1.1"
 human-readable = "1.12.0"
 jna = "5.18.0"
 kotlin = "2.2.20"
+kotlinx-serialization = "1.9.0"
 kotlinx-browser = "0.5.0"
 kotlinx-coroutines = "1.10.2"
 kotlinx-datetime = "0.7.1"
@@ -46,6 +47,8 @@ kotlinx-coroutines-swing = { module = "org.jetbrains.kotlinx:kotlinx-coroutines-
 kotlinx-coroutines-test = { module = "org.jetbrains.kotlinx:kotlinx-coroutines-test", version.ref = "kotlinx-coroutines" }
 kotlinx-datetime = { module = "org.jetbrains.kotlinx:kotlinx-datetime", version.ref = "kotlinx-datetime" }
 kotlinx-io = { module = "org.jetbrains.kotlinx:kotlinx-io-core", version.ref = "kotlinx-io" }
+kotlinx-serialization-core = { module = "org.jetbrains.kotlinx:kotlinx-serialization-core", version.ref = "kotlinx-serialization" }
+kotlinx-serialization-json = { module = "org.jetbrains.kotlinx:kotlinx-serialization-json", version.ref = "kotlinx-serialization" }
 material-icons-core = { module = "org.jetbrains.compose.material:material-icons-core", version.ref = "material-icons-core" }
 
 [plugins]
@@ -55,3 +58,4 @@ composeMultiplatform = { id = "org.jetbrains.compose", version.ref = "compose-mu
 composeCompiler = { id = "org.jetbrains.kotlin.plugin.compose", version.ref = "kotlin" }
 kotlinMultiplatform = { id = "org.jetbrains.kotlin.multiplatform", version.ref = "kotlin" }
 vanniktech-mavenPublish = { id = "com.vanniktech.maven.publish", version.ref = "vanniktech-mavenPublish" }
+kotlinSerialization = { id = "org.jetbrains.kotlin.plugin.serialization", version.ref = "kotlin" }

Original file line number	Diff line number	Diff line change
`@@ -4,6 +4,7 @@ import org.jetbrains.kotlin.gradle.dsl.JvmTarget`
`4`	`4`	`plugins {`
`5`	`5`	`alias(libs.plugins.androidLibrary)`
`6`	`6`	`alias(libs.plugins.kotlinMultiplatform)`
	`7`	`+ alias(libs.plugins.kotlinSerialization)`
`7`	`8`	`alias(libs.plugins.vanniktech.mavenPublish)`
`8`	`9`	`}`
`9`	`10`
`@@ -55,6 +56,9 @@ kotlin {`
`55`	`56`
`56`	`57`	`// Kotlinx IO`
`57`	`58`	`api(libs.kotlinx.io)`
	`59`	`+`
	`60`	`+ // Kotlinx Serialization`
	`61`	`+ implementation(libs.kotlinx.serialization.core)`
`58`	`62`	`}`
`59`	`63`
`60`	`64`	`commonTest.dependencies {`
`@@ -69,6 +73,9 @@ kotlin {`
`69`	`73`	`}`
`70`	`74`	`}`
`71`	`75`	`val nonWebTest by creating { dependsOn(commonTest.get()) }`
	`76`	`+ nonWebTest.dependencies {`
	`77`	`+ implementation(libs.kotlinx.serialization.json)`
	`78`	`+ }`
`72`	`79`
`73`	`80`	`val jvmAndNativeMain by creating { dependsOn(nonWebMain) }`
`74`	`81`