registry

A small dependency-injection / wiring library for Scala 3.

A Registry is a list of functions and values. The Registry main function, make[T], can be called to make a value of type T by invoking the first function that returns a T. The function parameters are retrieved by recursively calling make on the Registry. That's it!

Install

libraryDependencies ++= Seq(
  "org.atnos" %% "registry"            % "0.1.5",
  "org.atnos" %% "registry-scalacheck" % "0.1.5", // optional
  "org.atnos" %% "registry-cats"       % "0.1.5", // optional
  "org.atnos" %% "registry-cbor"       % "0.1.5", // optional
  "org.atnos" %% "registry-circe"      % "0.1.5", // optional
  "org.atnos" %% "registry-cbor"       % "0.1.5", // optional
)

Only registry is required; the others are integrations.

Hello, registry

import registry.*

case class Host(value: String)
case class Port(value: Int)
case class DbConfig(host: Host, port: Port)
case class App(db: DbConfig)

val r =
  fun[App] +:
    fun[DbConfig] +:
    value(Host("localhost")) +:
    value(Port(5432))

val app = r.make[App]
// App(DbConfig(Host("localhost"), Port(5432)))

What happens here?

fun[T] registers T's primary constructor.
value(x) registers a constant.
+: is the strict prepend: the compiler checks that every input on the left is produced by something on the right.
make creates the App.

Modules

Module	Purpose
`registry`	Core registry, entries, prepend operators, resolution.
`registry-cats`	Lift constructors into any `Applicative[F]` via `funTo[F, T]`.
`registry-cbor`	Derive borer `Encoder[T]` / `Decoder[T]` for CBOR encoding.
`registry-circe`	Derive `Encoder[T]` / `Decoder[T]` with configurable JSON options.
`registry-scalacheck`	Derive ScalaCheck `Gen[T]` for case classes and sealed hierarchies.

Documentation

The rendered site lives at https://etorreborre.github.io/registry-scala.

Sources are under docs/mdoc/ and are typechecked at build time via mdoc:

To build the docs locally:

sbt "~docs/mdoc"     # file-watch loop while editing

The docs are written to docs/target/mdoc/.

Building

This is a standard sbt project:

Compile with sbt compile.
Test with sbt test to run all specs2 suites.

Releasing

Push a tag of the form REGISTRY-X.Y.Z to main. The CI workflow will publish the jars to Maven Central and deploy the rendered docs to the gh-pages branch.

git tag REGISTRY-1.0.0
git push origin REGISTRY-1.0.0

Versions are computed from the tag by sbt-dynver. Publishing requires the following GitHub actions secrets:

SONATYPE_USERNAME
SONATYPE_PASSWORD
PGP_KEY_ID,
PGP_PASSPHRASE
PGP_SECRET

etorreborre / registry-scala 0.1.6