izumi.distage.config.codec

Config reader that uses a pureconfig.ConfigReader implicit instance for a type to decode it from Typesafe Config.

Always automatically derives a codec if it's not available.

Automatic derivation will use camelCase fields, NOT kebab-case fields, as in default pureconfig. It also overrides pureconfig's default type field type discriminator for sealed traits, instead using a circe-like format with a single-key object.

Example:

 sealed trait AorB
 final case class A(a: Int) extends AorB
 final case class B(b: String) extends AorB

 final case class Config(values: List[AorB])

In config:

 config {
   values = [
     { A { a = 123 } },
     { B { b = cba } }
   ]
 }

Auto-derivation will work without importing pureconfig.generic.auto._ and without any other imports

You may use izumi.distage.config.codec.PureconfigAutoDerive f you want to use DIConfigReader's deriving strategy to derive a standalone pureconfig codec:

 final case class Abc(a: Duration, b: Regex, c: URL)

 object Abc {
   implicit val configReader: pureconfig.ConfigReader[Abc] =
     PureconfigAutoDerive[Abc]
 }

Derive pureconfig.ConfigReader for A and for its fields recursively with pureconfig-magnolia

This differs from just using pureconfig.module.magnolia.auto.reader.exportReader by using different configuration, defined in PureconfigInstances, specifically:

1. Field name remapping is disabled, camelCase fields will remain camelCase, not kebab-case
2. Sealed traits are rendered as in circe, using a wrapper object with a single field, instead of using a type field. Example:

 sealed trait AorB
 final case class A(a: Int) extends AorB
 final case class B(b: String) extends AorB

 final case class Config(values: List[AorB])

in config:

 config {
   values = [
     { A { a = 123 } },
     { B { b = cba } }
   ]
 }