Set up project, initial impl for K8sDnsNameResolver

README, integration tests and release publishing will be set up in subsequent PRs.

Author: migesok

.github/workflows/ci.yml

@@ -0,0 +1,24 @@
+name: ci
+
+on:
+  push:
+    branches: [ main ]
+  pull_request:
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v5
+        with:
+          # fetch tags - tags are needed for versionPolicyCheck binary and source compat checks
+          fetch-tags: true
+      - uses: coursier/cache-action@v6
+      - uses: actions/setup-java@v5
+        with:
+          java-version: 17
+          distribution: temurin
+          cache: sbt
+      - uses: sbt/setup-sbt@v1
+      - name: sbt build
+        run: sbt clean build

.sbtopts

@@ -0,0 +1,8 @@
+# for using sbt-java-formatter on newer JDKs:
+-J--add-opens=java.base/java.lang=ALL-UNNAMED
+-J--add-opens=java.base/java.util=ALL-UNNAMED
+-J--add-exports=jdk.compiler/com.sun.tools.javac.api=ALL-UNNAMED
+-J--add-exports=jdk.compiler/com.sun.tools.javac.file=ALL-UNNAMED
+-J--add-exports=jdk.compiler/com.sun.tools.javac.parser=ALL-UNNAMED
+-J--add-exports=jdk.compiler/com.sun.tools.javac.tree=ALL-UNNAMED
+-J--add-exports=jdk.compiler/com.sun.tools.javac.util=ALL-UNNAMED

.scalafmt.conf

@@ -0,0 +1,99 @@
+# Main goals:
+# - nicer commit diffs (trailing commas, no alignment for pattern matching, force new lines)
+# - better interop with default IntelliJ IDEA setup (matching import and modifiers sorting logic)
+# - better developer experience on laptop screens (like 16' MBPs) with IntelliJ IDEA (line wraps)
+
+version = 3.9.9
+
+runner.dialect = scala213source3
+fileOverride {
+  "glob:**/scala-3/**/*.scala" {runner.dialect = scala3}
+}
+
+# only format files tracked by git
+project.git = true
+
+maxColumn = 110
+trailingCommas = always
+
+preset = default
+# do not align to make nicer commit diffs
+align.preset = none
+
+indent {
+  # altering defnSite and extendSite to have this:
+  #   final class MyErr extends RuntimeException(
+  #     "super error message",
+  #   )
+  # instead of this:
+  #   final class MyErr extends RuntimeException(
+  #       "super error message",
+  #     )
+  defnSite = 2
+  extendSite = 0
+}
+
+spaces {
+  # makes string interpolation with curlies more visually distinct
+  inInterpolatedStringCurlyBraces = true
+}
+
+newlines {
+  # keep author new lines where possible
+  source = keep
+  # force new line after "(implicit" for multi-line arg lists
+  implicitParamListModifierForce = [after]
+  avoidForSimpleOverflow = [
+    tooLong, # if the line would be too long even after newline inserted, do nothing
+    slc, # do nothing if overflow caused by single line comment
+  ]
+}
+
+verticalMultiline {
+  atDefnSite = true
+  arityThreshold = 4 # more than 3 args in a list will be turned vertical
+  newlineAfterOpenParen = true # for nicer commit diffs
+}
+
+# for nicer commit diffs - forces new line before last parenthesis:
+#   class MyCls(
+#     arg1: String,
+#     arg2: String,
+#   ) extends MyTrait {
+#
+# without it:
+#   class MyCls(
+#     arg1: String,
+#     arg2: String) extends MyTrait {
+danglingParentheses.exclude = []
+
+docstrings {
+  # easier to view diffs in IDEA on 16' MBP screen if docs max line are shorter than code
+  wrapMaxColumn = 90
+  # next settings make it similar to the default IDEA javadoc formatting
+  style = Asterisk
+  oneline = unfold
+  blankFirstLine = unfold
+}
+
+rewrite.rules = [
+  Imports,
+  RedundantParens,
+  SortModifiers,
+  prefercurlyfors,
+]
+
+# put visibility modifier first
+rewrite.sortModifiers.preset = styleGuide
+
+# Import sorting as similar as possible to scalafix's "OrganizeImports.preset = INTELLIJ_2020_3".
+# Scalafix is not used as its commands mess up "all .." build aliases and it takes long time to run,
+# while its code semantic based features are not needed here.
+# I.e. detection of unused imports is done with Scala compiler options.
+rewrite.imports {
+  sort = ascii
+  groups = [
+    [".*"],
+    ["java\\..*", "javax\\..*", "scala\\..*"],
+  ]
+}

build.sbt

@@ -0,0 +1,75 @@
+import Dependencies.*
+import sbt.*
+
+ThisBuild / organization := "com.evolution.jgrpc.tools"
+ThisBuild / startYear := Some(2025)
+ThisBuild / homepage := Some(url("https://github.com/evolution-gaming/grpc-java-tools"))
+ThisBuild / licenses := Seq(("MIT", url("https://opensource.org/licenses/MIT")))
+ThisBuild / organizationName := "Evolution"
+ThisBuild / organizationHomepage := Some(url("https://evolution.com"))
+
+// Maven Central requires <developers> in published pom.xml files
+ThisBuild / developers := List(
+  Developer(
+    id = "migesok",
+    name = "Mikhail Sokolov",
+    email = "[email protected]",
+    url = url("https://github.com/migesok"),
+  ),
+)
+
+ThisBuild / scmInfo := Some(ScmInfo(
+  browseUrl = url("https://github.com/evolution-gaming/grpc-java-tools"),
+  connection = "[email protected]:evolution-gaming/grpc-java-tools.git",
+))
+
+// not sure if bincompat check works for Java code, put it here just in case
+ThisBuild / versionPolicyIntention := Compatibility.BinaryCompatible
+
+// this is a Java project, setting a fixed Scala version just in case
+ThisBuild / scalaVersion := "2.13.16"
+
+// setting pure-Java module build settings
+ThisBuild / crossPaths := false // drop off Scala suffix from artifact names.
+ThisBuild / autoScalaLibrary := false // exclude scala-library from dependencies
+ThisBuild / javacOptions := Seq("-source", "17", "-target", "17", "-Werror", "-Xlint:all")
+ThisBuild / doc / javacOptions := Seq("-source", "17", "-Xdoclint:all", "-Werror")
+
+// common test dependencies:
+ThisBuild / libraryDependencies ++= Seq(
+  // to be able to run JUnit 5+ tests:
+  "com.github.sbt.junit" % "jupiter-interface" % JupiterKeys.jupiterVersion.value,
+  Slf4j.simple,
+).map(_ % Test)
+
+// common compile dependencies:
+ThisBuild / libraryDependencies ++= Seq(
+  jspecify, // JSpecify null-check annotations
+)
+
+lazy val root = project.in(file("."))
+  .settings(
+    name := "grpc-java-tools-root",
+    description := "Evolution grpc-java tools - root",
+    publish / skip := true,
+  )
+  .aggregate(
+    k8sDnsNameResolver,
+  )
+
+lazy val k8sDnsNameResolver = project.in(file("k8s-dns-name-resolver"))
+  .settings(
+    name := "k8s-dns-name-resolver",
+    description := "Evolution grpc-java tools - DNS-based name resolver for Kubernetes services",
+    libraryDependencies ++= Seq(
+      Grpc.api,
+      Slf4j.api,
+      dnsJava,
+    ),
+  )
+
+addCommandAlias("fmt", "all scalafmtAll scalafmtSbt javafmtAll")
+addCommandAlias(
+  "build",
+  "all scalafmtCheckAll scalafmtSbtCheck javafmtCheckAll versionPolicyCheck Compile/doc test",
+)