Ignore parse exceptions for kotlinx-serialization

The problem is how to ignore the parse exceptions if the property is nullable, for example:

@Serializable
data class Data(a: Int = 0, b: Int? = null)
val data = Json.parse(Data.serializer(), "{a: 1, b: 2.0}") // throws NumberFormatException

We expected the

// No exception
assertThat(data.a).isEqualTo(1)
assertThat(data.b).isNull()

kotlinx-serialization parsing is in strict mode by default.

Even we disabled it, it doesn’t work on this case. So we decided to implement it by ourselves to throw nothing if strictMode disabled.

Installation:

repositories {
  maven { url "https://jitpack.io" }
}
dependencies {
  implementation 'com.github.yongjhih.kotlinx-serialization:kotlinx-serialization-runtime:13496cbef6'
}

So now:

val data = Json.nonstrict.parse(Data.serializer(), "{a: 1, b: 2.0}") // No NumberFormatException

Bonus — Error Handler

val data = Json(errorHandler = { e -> e.printStackTrace() }).parse(Data.serializer(), "{a: 1, b: 2.0}") // printStackTrace() for any exception whenever throwing

Implementation:

Add nonStrictJsonCanSkipNullablePrimitivesValues test case · yongjhih/kotlinx-serialization@13496cb

|              single<Converter.Factory> {
|                  Json(strictMode = false,
| -                     encodeDefaults = false).asConverterFactory(MediaType.get("application/json"))
| +                     encodeDefaults = false,
| +                     errorHandler = { e ->
| +                       Timber.e(e)
| +                     }).asConverterFactory(MediaType.get("application/json"))
|              }