Add serializer for message key cache

androiddoubleratchet/build.gradle

@@ -1,6 +1,11 @@
 apply plugin: 'com.android.library'
 apply plugin: 'kotlin-android'
 apply plugin: 'kotlin-android-extensions'
+apply plugin: 'kotlinx-serialization'
+apply plugin: 'maven-publish'
+
+def artifactId = 'AndroidDoubleRatchet'
+def groupId = 'com.ticeapp.androiddoubleratchet'
 
 android {
     compileSdkVersion 29
@@ -10,7 +15,7 @@ android {
         minSdkVersion 16
         targetSdkVersion 29
         versionCode 1
-        versionName "1.0"
+        versionName "1.0.1"
 
         testInstrumentationRunner "androidx.test.runner.AndroidJUnitRunner"
         consumerProguardFiles 'consumer-rules.pro'
@@ -36,4 +41,20 @@ dependencies {
     implementation "com.goterl.lazycode:lazysodium-android:4.1.0@aar"
     implementation 'net.java.dev.jna:jna:5.5.0@aar'
     implementation 'com.github.TICESoftware:AndroidHKDF:1.0.0'
+    implementation "org.jetbrains.kotlin:kotlin-stdlib:$kotlin_version"
+    implementation "org.jetbrains.kotlinx:kotlinx-serialization-runtime:0.20.0"
 }
+
+project.afterEvaluate {
+    publishing {
+        publications {
+            library(MavenPublication) {
+                setGroupId groupId
+                setArtifactId artifactId
+                version android.defaultConfig.versionName
+
+                artifact bundleReleaseAar
+            }
+        }
+    }
+}

androiddoubleratchet/src/main/java/com/ticeapp/androiddoubleratchet/MessageKeyCache.kt

@@ -1,6 +1,7 @@
 package com.ticeapp.androiddoubleratchet
 
 import com.goterl.lazycode.lazysodium.utils.Key
+import kotlinx.serialization.*
 
 internal class MessageKeyCache {
     data class MessageIndex(val publicKey: Key, val messageNumber: Int)
@@ -49,4 +50,13 @@ internal class MessageKeyCache {
 }
 
 typealias MessageKeyCacheState = ArrayList<MessageKeyCacheEntry>
-data class MessageKeyCacheEntry(val publicKey: Key, val messageNumber: Int, val messageKey: Key)
+
+@Serializable
+data class MessageKeyCacheEntry(@Serializable(with = KeySerializer::class) val publicKey: Key, val messageNumber: Int, @Serializable(with = KeySerializer::class) val messageKey: Key)
+
+class KeySerializer: KSerializer<Key> { //SerializationStrategy<Key>, DeserializationStrategy<Key> {
+    override val descriptor: SerialDescriptor = PrimitiveDescriptor("Key", PrimitiveKind.STRING)
+    override fun serialize(encoder: Encoder, value: Key) = encoder.encodeString(value.asHexString)
+    override fun deserialize(decoder: Decoder): Key = Key.fromHexString(decoder.decodeString())
+    override fun patch(decoder: Decoder, old: Key): Key = deserialize(decoder)
+}

build.gradle

@@ -11,6 +11,7 @@ buildscript {
         classpath 'com.android.tools.build:gradle:3.6.2'
         classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlin_version"
         classpath 'com.github.dcendents:android-maven-gradle-plugin:2.1'
+        classpath "org.jetbrains.kotlin:kotlin-serialization:$kotlin_version"
 
         // NOTE: Do not place your application dependencies here; they belong
         // in the individual module build.gradle files