Hello everyone, is someone able to help me please with my StackOverflow question?
I didn't try, but you could probably also use rename https://stackoverflow.com/questions/40306107/rename-json-fields-with-circe
But the backticks are fine. That's a scala language-level behavior for escaping reserved keywords
Hi, I love to use this library. I'm going to parse JSON as shapeless' Labelled HList using circe.shapes:
import shapeless._ // for HList syntax
import shapeless.labelled._ // for FieldType
import shapeless.syntax.singleton._ // for ->> syntax
type FB = FieldType["foo", String] :: FieldType["bar", String] :: HNil
val fb: FB = ("foo" ->> "this is foo") :: ("bar" ->> "this is bar") :: HNil
// fb: FB = "this is foo" :: "this is bar" :: HNil
import io.circe._, io.circe.generic.auto._, io.circe.parser._, io.circe.syntax._
import io.circe.shapes._
val fbj = """{"foo": "hoge", "bar": "fuga"}"""
// fbj: String = "{\"foo\": \"hoge\", \"bar\": \"fuga\"}"
val Right(fb1: FB) = decode[FB](fbj)
// fb1: FB = "hoge" :: "fuga" :: HNil
val fbj2 = """{}"""
// fbj2: String = "{}"
val Left(err) = decode[FB](fbj2)
// err: Error = DecodingFailure(Record, List())
// I'd like to make fields optional:
type OptionalFB =
FieldType["foo", Option[String]] :: FieldType["bar", Option[String]] :: HNil
val Left(err2) = decode[OptionalFB](fbj2)
// err2: Error = DecodingFailure(Record, List())
// it requires existence of field...
val fbj22 = """{"foo": null, "bar": null}"""
// fbj22: String = "{\"foo\": null, \"bar\": null}"
val Right(ex) = decode[OptionalFB](fbj22)
// ex: OptionalFB = None :: None :: HNil
// Then I captured entire field into Option:
type OptionalFB2 =
Option[FieldType["foo", String]] :: Option[FieldType["bar", String]] :: HNil
val optionalFB2Example: OptionalFB2 = None :: None :: HNil
// optionalFB2Example: OptionalFB2 = None :: None :: HNil
// However below doesn't compile:
// val Right(fb2) = decode[OptionalFB2](fbj2)Is there way to decode JSON as Optional Labelled HList? Some of my JSON has optional field, and I want to express optional field in Labelled HList.
case class e.g. case class(foo: Option[String], bar: Option[String]) .
io.circe:circe-optics_2.12:0.14.1 are causing numerous conflicts when attempting to migrate to Scala 3. I don't have that many uses of circe-optics. Am I better off dropping circe-optics? or attempting to play the dependency conflict-resolution game? Or is there some Scala 3 solution for circe-optics that I somehow missed?[error] Modules were resolved with conflicting cross-version suffixes in ProjectRef(uri("file:/D:/Projects/Git/tag/"), "tag-server"):
[error] org.typelevel:cats-free _2.13, _3
[error] io.circe:circe-core _3, _2.13
[error] org.typelevel:simulacrum-scalafix-annotations _2.13, _3
[error] org.typelevel:cats-kernel _3, _2.13
[error] org.typelevel:cats-core _3, _2.13
[error] io.circe:circe-numbers _3, _2.13
[error] java.lang.RuntimeException: Conflicting cross-version suffixes in: org.typelevel:cats-free, io.circe:circe-core, org.typelevel:simulacrum-scalafix-annotations, org.typelevel:cats-kernel, org.typelevel:cats-core, io.circe:circe-numbers
As a workaround you can use jsoniter-scala codecs.
They are handy in derivation and much more efficient in the runtime :
import com.github.plokhotnyuk.jsoniter_scala.core._
import com.github.plokhotnyuk.jsoniter_scala.macros._
implicit val codec: JsonValueCodec[Test] = JsonCodecMaker.make(CodecMakerConfig.withDiscriminatorFieldName(None))
println(readFromString[Test](sample))Full code: https://scastie.scala-lang.org/fZmal0NeSt605Wf4VVS5Kg
[error] sbt.librarymanagement.ResolveException: Error downloading io.circe:circe-generic-extras_2.13:0.14.3
...
[error] not found: https://repo1.maven.org/maven2/io/circe/circe-generic-extras_2.13/0.14.3/circe-generic-extras_2.13-0.14.3.pomMaximal number of successive inlines (32) exceeded,
Maybe this is caused by a recursive inline method?
You can use -Xmax-inlines to change the limit.
implicit val decoder:Decoder[Thing] = deriveDecoder[Thing]
-Xmax-inlines
import io.circe.syntax._
import io.circe.{Decoder, Encoder}
import io.circe.generic.semiauto.{deriveDecoder, deriveEncoder}
implicit val decoder:Decoder[Thing] = deriveDecoder[Thing]
implicit val encoder:Encoder[Thing] = deriveEncoder[Thing][error] sbt.librarymanagement.ResolveException: Error downloading io.circe:circe-generic-extras_2.13:0.14.3 ... [error] not found: https://repo1.maven.org/maven2/io/circe/circe-generic-extras_2.13/0.14.3/circe-generic-extras_2.13-0.14.3.pomI can't find this artifact for 0.14.3 release. Can someone check it?
stupid me, circe-generic-extras is released independently :facepunch:
I have this json :
{
"result":
{
"name": "test",
"foo": {
},
"baz": {
....
}
}and classes
case classe fooResult(name : String, foo :Foo)
object fooResult{
import io.circe.syntax._
import io.circe.{Decoder, Encoder}
import io.circe.generic.semiauto.{deriveDecoder, deriveEncoder}
implicit val decoder:Decoder[fooResult] = deriveDecoder[fooResult]
}
case classe Foo (...)
case classe baz (...) i want to decode only foo part in the json and not take baz part
i have a code the retrives the whole hson and not only
"name": "test",
"foo": {
}how can this be achieved?
Hi all, how can I do the following with ACursor? The reason for this is running Decoder[..].prepare()
def merge(key1: String, key2: String)(in: ACursor): ACursor
Such that
If we have an object {a: {items in A}, b: {items in B}}, if key1 = a, and key2 = b, then we get back {items in A, deep merged with items in B}?
Hi - I am trying to derive an encoder for a case class that is a member of a higher kinded sealed trait which also takes a type argument of the same type:
sealed trait Expression[T] {
def doIt(s: String): Either[String, T]
}
object Expression {
implicit def lowPriorityEncoder: Encoder[Expression[_]] = deriveEncoder
implicit def lowPriorityDecoder: Decoder[Expression[_]] = deriveDecoder
implicit def stringExpressioncoder: Encoder[Expression[String]] = deriveEncoder
implicit def stringExpressionDecoder: Decoder[Expression[String]] = deriveDecoder
implicit def booleanExpressionEncoder: Encoder[Expression[Boolean]] = deriveEncoder
implicit def booleanExpressionDecoder: Decoder[Expression[Boolean]] = deriveDecoder
}
case class X[F[_] <: Expression[_], T](x: F[T]) extends Expression[Boolean] {
override def doIt(s: String): Either[String, Boolean] = ???
}
object X {
implicit def typeEncoder[F[_] <: Expression[_], T](implicit FT: Encoder[F[T]]): Encoder[X[F, T]] = deriveEncoder
}I am unable to derive the encoder for X - can anyone tell me what I am missing or if this is even possible?
val node = c.downField("attribute1").asInstanceOf[HCursor]
How to do this :
if node is of type Text : meaning : "attribute1"="sdfdfd"
if node is of type Int : meaning : "attribute1"=1
if node is of type Double : meaning : "attribute1"=0.1
if node is of type Array : meaning : "attribute1"=[]
if node is of type Object : meaning : "attribute1"={}
etc..- The name of the type of the JSON value.
*/
final def name: String =
this match {
case JNull => "Null"
case JBoolean() => "Boolean"
case JNumber() => "Number"
case JString() => "String"
case JArray() => "Array"
case JObject(_) => "Object"
}
Mirror.of I don't really get the problem. Their is somethiong special to do when you move from scala2 to Scala3 in case of Circe ?
@Fabszn can you try to post on the Circe GitHub Issue perhaps? It seems responses here are far and few inbetween, because some people moved to Discord I believe.
If you can also provide a minimal reproduction of the issue you are having that would definitely help resolve the issue.
1 reply
1 reply
Hi there, I'm attempting to use circe to serialize an ADT. I'm trying to follow the guides, here: https://circe.github.io/circe/codecs/adt.html, but in my use case I have a generic List[T] data type (vs the List[String] in the example). Is there some way to account for this (maybe by asserting that there is an Encoder[T] via an implicit param?) in my code so that things work?
Full code looks something like
sealed trait FeatureValue extends Any
object FeatureValue {
case class BooleanFeature(value: Boolean) extends AnyVal with FeatureValue
case class DoubleFeature(value: Double) extends AnyVal with FeatureValue
case class IntFeature(value: Int) extends AnyVal with FeatureValue
case class StringFeature(value: String) extends AnyVal with FeatureValue
case class ListFeature[T](value: List[T]) extends FeatureValue
}And I'm currently using the circe-shapes method described in the docs
Hello,
I have this json and i wrote those classes and try to decode it
{
"values" : [
[
"p1",
{
"desc" : "product1",
"price" : "150",
}
],
[
"p2",
{
"cl_type" : "product1",
"price" : "66",
}
]
]
}
case class Test(values : Seq(Arg))
case class Arg (name : String, val:Value)
case class Value (desc : String, price:Int)Any idea how to decode values which contains array of array ?
Thnx
Hello,
I have this code where i'm calling get on Option in a Try block.
Is that ok or it s antipattern ?
Thnx
case class Tag(bytes : Array[Byte])
object Tag{
def getBytes(ta:Tag) : Option[Array[Byte]] = {
...//do some comuptation with bytes attributes
}
}
case class Test(desc:String, tag : Tag)
object Test{
def method_2 (value : Tag) : Option[Array[Byte]] = Try{
val arrayB = new ArrayBuilder.ofByte
arrayBuilder.addAll(Tag.getBytes(value).get)
}.toOption
}None in most cases then your server can overuse CPU like under DoS attack. For more info please read this great article: https://shipilev.net/blog/2014/exceptional-performance/
