Protoファイルを使用しないProto DataStore実装

2024/09/30 【GO/note/令和トラベル】After iOSDC & DroidKaigi 2024
https://reiwatravel.connpass.com/event/327079/

Transcript

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7. syntax = "proto3"; option java_package = "com.codelab.android.datastore"; option java_multiple_files = true; message UserPreferences { // filter for showing / hiding completed tasks bool show_completed = 1; }
8. syntax = "proto3"; option java_package = "com.codelab.android.datastore"; option java_multiple_files = true; message UserPreferences { // filter for showing / hiding completed tasks bool show_completed = 1; }
9. σʔλΫϥεͷ࡞੒ import com.squareup.moshi.Json import kotlinx.serialization.Serializable @Serializable data class Person( @Json(name = "name") var name: String = "", @Json(name = "age") var age: Int = 0, )
10. 4FSJBMJ[FSΛ࡞੒ class PersonSerializer( private val stringFormat: StringFormat = Json { ignoreUnknownKeys = true encodeDefaults = true }, ) : Serializer<Person> { override val defaultValue: Person get() = Person() override suspend fun readFrom(input: InputStream): Person { try { val bytes = input.readBytes() val string = bytes.decodeToString() return stringFormat.decodeFromString(string) //ɹPersonΫϥεʹσίʔυͯ͠ಡΈऔΔ } catch (e: SerializationException) { throw CorruptionException("Cannot read stored data", e) } } override suspend fun writeTo(t: Person, output: OutputStream) { val string = stringFormat.encodeToString(t) val bytes = string.encodeToByteArray() // PersonΫϥε͔ΒΤϯίʔυͯ͠ॻ͖ࠐΉ withContext(Dispatchers.IO) { output.write(bytes) } } }
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