(Experimental) Google APIs client code generator

⚠️ This project is in an experimental stage (with a messy code base), use with care if you want to give it a try.

Generates client code from Google's disovery document for your Scala (3) tech stack.
Currently it provides following configurations for generated code:

Http sources: Sttp4, Sttp3
JSON codecs: Jsoniter, ZioJson
JSON Array collection type: List, Vector, Array, ZioChunk

NOTE: Generated code does not include authentication.

If you're using http4s and circe you may also want to check some similar projects:

Usage

The generator can be used with any tool that can perform system calls to a command line executable or add Scala 3 dependencies (e.g. scala command line, sbt 1, sbt 2, mill, etc.).

Usage via Scala command line example

See example under example/generate.scala.

//> using scala 3.6.3
//> using dep dev.rolang::gcp-codegen::0.0.1

import gcp.codegen.*, java.nio.file.*, GeneratorConfig.*

@main def run =
  val files = Task(
    specsInput = SpecsInput.FilePath(Path.of("pubsub_v1.json")),
    config = GeneratorConfig(
      outDir = Path.of("out"),
      outPkg = "example.pubsub.v1",
      httpSource = HttpSource.Sttp4,
      jsonCodec = JsonCodec.Jsoniter,
      dialect = Dialect.Scala3,
      arrayType = ArrayType.List,
      preprocess = specs => specs
    )
  ).runAwait()
  println(s"Generated ${files.length} files")

Run example:

cd example && scala generate.scala && scala fmt ./out

See output in example/out.

Command-line executable usage

Configuration parameters (currently supported):

Configuration	Description	Options	Default
-specs	Can be `stdin` or a path to the JSON file.
-out-dir	Ouput directory
-out-pkg	Output package
-http-source	Generated http source.	Sttp4, Sttp3
-json-codec	Generated JSON codec	Jsoniter, ZioJson
-array-type	Collection type for JSON arrays	`List`, `Vector`, `Array`, `ZioChunk`	`List`
-include-resources	Optional resource filter.

Examples:

Command line binaries are not published (not yet).
A command line binary can be built from the source via sbt buildCliBinary.
The output directory is modules/cli/target/bin.
E.g. on Linux the output file will be like modules/cli/target/bin/gcp-codegen-x86_64-linux.

curl 'https://pubsub.googleapis.com/$discovery/rest?version=v1' > pubsub_v1.json

# the path to the executable may be different
./modules/cli/target/bin/gcp-codegen-x86_64-linux \
 --out-dir=src/scala/main/generated \
 --specs=./pubsub_v1.json \
 --resources-pkg=gcp.pubsub.v1.resources \
 --schemas-pkg=gcp.pubsub.v1.schemas \
 --http-source=sttp4 \
 --json-codec=jsoniter \
 --include-resources='projects.*,!projects.snapshots' # optional filters

Building and testing

Generate, compile and run tests for generated code

sbt buildCliBinary test

rolang / google-rest-api-codegen 0.0.1