native POJO codec not recognized

[Vincent Lee]

I can't get the mapping to work using native or jackson and could use some guidance.  

build.gradle.kts

// plugins 

kotlin("jvm") version "1.4.10"

// dependencies

implementation("org.litote.kmongo:kmongo-native:4.1.2")

db init

val client = KMongo.createClient() 

codecRegistries = CodecRegistries.fromRegistries( // save uuids as UUID, instead of LUUID
CodecRegistries.fromProviders(
PojoCodecProvider
.builder()
.automatic(true)
.build()),
MongoClientSettings.getDefaultCodecRegistry()
)
mongoConnection = client.getDatabase("property").withCodecRegistry(codecRegistries())

usage 

data class UserEntity @BsonCreator constructor(
@BsonId val _id: String,
@BsonProperty("name") val name: String,
@BsonProperty("email") val email: String)

database.getMongoConnection()
.getCollection<UserEntity>()

.find()

.toList()

// errors here

[qtp60559178-18] WARN org.bson.codecs.pojo - Cannot use 'UserEntity' with the PojoCodec.

java.lang.IllegalArgumentException: propertyName can not be null

Connection to db and everything else is fine.

Thanks in advance!

[zigzago]

Hello,

Your code removes the KMongo native codec registry. Just insert the custom codec like this:

val mongoConnection = client.getDatabase("property").run {

     withCodecRegistry(

         CodecRegistries.fromProviders(

            //your custom codec

            UuidCodecProvider(/*chose the UuidRepresentation you need*/),

           //default codec registry with kmongo codec registry set by KMongo

            codecRegistry

)

}

HTH

[Vincent Lee]

Ok, I've followed the instructions but I'm still getting the same error 

Can't find a codec for class propertymanager.modules.users.UserEntity.

Entity definition

@Entity // no-arg constructor 
data class UserEntity(@BsonId val _id: UUID, val name: String, val email: String)

Database init

val client = KMongo.createClient()
val database = client.getDatabase("property")
.run {
    withCodecRegistry(
        CodecRegistries.fromRegistries(
            CodecRegistries.fromProviders(
                UuidCodecProvider(UuidRepresentation.STANDARD)),
                MongoClientSettings.getDefaultCodecRegistry())) 
}

Query

private val collection = database.getMongoConnection().getCollection<UserEntity>("users")

collection.find().toList() // Can't find a codec for class UserEntity.

[Vincent Lee]

fixed formatting 

val client = KMongo.createClient()
val database = client.getDatabase("property")
.run {
    withCodecRegistry(
        CodecRegistries.fromRegistries(

            CodecRegistries.fromProviders(UuidCodecProvider(UuidRepresentation.STANDARD),MongoClientSettings.getDefaultCodecRegistry())

        )

   )
}

[zigzago]

Do not use MongoClientSettings.getDefaultCodecRegistry(), use this.getCodecRegistry(). MongoClientSettings.getDefaultCodecRegistry() does not contain KMongo codec registry.

[Vincent Lee]

ugh that's clear now. thank you!