Dogfood v2

app/build.gradle.kts

@@ -21,7 +21,6 @@ dependencies {
         isTransitive = false
     }
 
-    //testRuntimeOnly(kotlin("reflect"))
     testImplementation(libs.kotest.assertions)
     testImplementation(libs.kotest.runner)
     testImplementation(libs.ktor.server.core)

app/src/dist/share/gradle.nix

@@ -0,0 +1,292 @@
+# This file is generated by gradle2nix.
+#
+# Example usage (e.g. in default.nix):
+#
+#     with (import <nixpkgs> {});
+#     let
+#       buildGradle = callPackage ./gradle.nix {};
+#     in
+#       buildGradle {
+#         lockFile = ./gradle.lock;
+#
+#         src = ./.;
+#
+#         gradleFlags = [ "installDist" ];
+#
+#         installPhase = ''
+#           mkdir -p $out
+#           cp -r app/build/install/myproject $out
+#         '';
+#       }
+
+{ lib
+, stdenv
+, buildEnv
+, fetchs3
+, fetchurl
+, gradle
+, maven
+, runCommandLocal
+, symlinkJoin
+, writeText
+, writeTextDir
+}:
+
+{
+  # Path to the lockfile generated by gradle2nix (e.g. gradle.lock).
+  lockFile
+, pname ? "project"
+, version ? null
+, enableParallelBuilding ? true
+# Arguments to Gradle used to build the project in buildPhase.
+, gradleFlags ? [ "build" ]
+# Enable debugging for the Gradle build; this will cause Gradle to run a debug server
+# and wait for a JVM debugging client to attach.
+, enableDebug ? false
+# Additional code to run in the Gradle init script (init.gradle).
+, extraInit ? ""
+# Override the default JDK used to run Gradle itself.
+, buildJdk ? null
+# Override functions which fetch dependency artifacts.
+# Keys in this set are URL schemes such as "https" or "s3".
+# Values are functions which take a dependency in the form
+# `{ urls, hash }` and fetch into the Nix store. For example:
+#
+#   {
+#     s3 = { name, urls, hash }: fetchs3 {
+#       s3url = builtins.head urls;
+#       # TODO This doesn't work without patching fetchs3 to accept SRI hashes
+#       inherit name hash;
+#       region = "us-west-2";
+#       credentials = {
+#         access_key_id = "foo";
+#         secret_access_key = "bar";
+#       };
+#     };
+#   }
+, fetchers ? { }
+, ... } @ args:
+
+let
+  inherit (builtins)
+    attrValues concatStringsSep elemAt filter fromJSON getAttr hasAttr head length match
+    removeAttrs replaceStrings sort;
+
+  inherit (lib)
+    assertMsg concatMapStringsSep findFirst foldl' groupBy' hasSuffix hasPrefix last mapAttrs
+    mapAttrsToList optionalAttrs optionalString readFile removeSuffix unique versionAtLeast
+    versionOlder;
+
+  inherit (lib.strings) sanitizeDerivationName;
+
+  lockedDeps = fromJSON (readFile lockFile);
+
+  toCoordinates = id:
+    let
+      coords = builtins.split ":" id;
+    in rec {
+      group = elemAt coords 0;
+      module = elemAt coords 2;
+      version = elemAt coords 4;
+      versionParts = parseVersion version;
+    };
+
+  parseVersion = version:
+    let
+      parts = builtins.split ":" version;
+      base = elemAt parts 0;
+    in
+      {
+        inherit base;
+        exact = base;
+      }
+      // optionalAttrs (length parts >= 2) (
+        let
+          snapshot = elemAt parts 2;
+          exact = replaceStrings [ "-SNAPSHOT" ] [ "-${snapshot}" ] base;
+          parts = builtins.split "-" timestamp;
+          timestamp = findFirst (match "[0-9]{8}\.[0-9]{6}") parts;
+          buildNumber = let lastPart = last parts; in if match "[0-9]+" lastPart then lastPart else null;
+        in
+          { inherit snapshot exact timestamp buildNumber; }
+      );
+
+  fetchers' = {
+    http = fetchurl;
+    https = fetchurl;
+  } // fetchers;
+
+  # Fetch urls using the scheme for the first entry only; there isn't a
+  # straightforward way to tell Nix to try multiple fetchers in turn
+  # and short-circuit on the first successful fetch.
+  fetch = name: { urls, hash }:
+    let
+      first = head urls;
+      scheme = head (builtins.match "([a-z0-9+.-]+)://.*" first);
+      fetch' = getAttr scheme fetchers';
+      urls' = filter (hasPrefix scheme) urls;
+    in
+      fetch' { urls = urls'; inherit hash; };
+
+  mkModule = id: artifacts:
+    let
+      coords = toCoordinates id;
+      modulePath = "${replaceStrings ["."] ["/"] coords.group}/${coords.module}/${coords.version}";
+    in
+      stdenv.mkDerivation {
+        pname = sanitizeDerivationName "${coords.group}-${coords.module}";
+        version = coords.versionParts.exact;
+
+        srcs = mapAttrsToList fetch artifacts;
+
+        dontPatch = true;
+        dontConfigure = true;
+        dontBuild = true;
+        dontFixup = true;
+        dontInstall = true;
+
+        preUnpack = ''
+          mkdir -p "$out/${modulePath}"
+        '';
+
+        unpackCmd = ''
+          cp "$curSrc" "$out/${modulePath}/$(stripHash "$curSrc")"
+        '';
+
+        sourceRoot = ".";
+
+        preferLocalBuild = true;
+        allowSubstitutes = false;
+      };
+
+  offlineRepo = symlinkJoin {
+    name = if version != null then "${pname}-${version}-gradle-repo" else "${pname}-gradle-repo";
+    paths = mapAttrsToList mkModule lockedDeps;
+  };
+
+  initScript =
+    let
+      inSettings = pred: script:
+        optionalString pred (
+          if versionAtLeast gradle.version "6.0" then ''
+            gradle.beforeSettings {
+              ${script}
+            }
+          '' else ''
+            gradle.settingsEvaluated {
+              ${script}
+            }
+          ''
+        );
+    in
+      writeText "init.gradle" ''
+        static def offlineRepo(RepositoryHandler repositories) {
+            repositories.clear()
+            repositories.mavenLocal {
+                url 'file:${offlineRepo}'
+                metadataSources {
+                    gradleMetadata()
+                    mavenPom()
+                    artifact()
+                }
+            }
+        }
+
+        ${inSettings (versionAtLeast gradle.version "6.0") ''
+          offlineRepo(it.buildscript.repositories)
+        ''}
+
+        ${inSettings true ''
+            offlineRepo(it.pluginManagement.repositories)
+        ''}
+
+        gradle.projectsLoaded {
+            allprojects {
+                buildscript {
+                    offlineRepo(repositories)
+                }
+            }
+        }
+
+        ${if versionAtLeast gradle.version "6.8"
+          then ''
+            gradle.beforeSettings {
+                it.dependencyResolutionManagement {
+                    offlineRepo(repositories)
+                    repositoriesMode.set(RepositoriesMode.PREFER_SETTINGS)
+                }
+            }
+          ''
+          else ''
+            gradle.projectsLoaded {
+                allprojects {
+                    offlineRepo(repositories)
+                }
+            }
+          ''
+        }
+
+        ${extraInit}
+      '';
+
+  buildProject = flags: ''
+    gradle --offline --no-daemon --no-build-cache \
+      --info --full-stacktrace --warning-mode=all \
+      --no-configuration-cache \
+      -Dmaven.repo.local=${offlineRepo} \
+      ${optionalString enableParallelBuilding "--parallel"} \
+      ${optionalString enableDebug "-Dorg.gradle.debug=true"} \
+      ${optionalString (buildJdk != null) "-Dorg.gradle.java.home=${buildJdk.home}"} \
+      --init-script ${initScript} \
+      ${concatStringsSep " " flags}
+  '';
+
+in stdenv.mkDerivation ({
+
+  dontStrip = true;
+
+  nativeBuildInputs = (args.nativeBuildInputs or []) ++ [ gradle ];
+
+  buildPhase = args.buildPhase or ''
+    runHook preBuild
+
+    (
+    set -eux
+
+    ${optionalString (versionOlder gradle.version "8.0") ''
+      # Work around https://github.com/gradle/gradle/issues/1055
+      TMPHOME="$(mktemp -d)"
+      mkdir -p "$TMPHOME/init.d"
+      export GRADLE_USER_HOME="$TMPHOME"
+      cp ${initScript} $TMPHOME/
+    ''}
+
+    gradle --offline --no-daemon --no-build-cache \
+      --info --full-stacktrace --warning-mode=all \
+      --no-configuration-cache --console=plain \
+      -Dmaven.repo.local=${offlineRepo} \
+      ${optionalString enableParallelBuilding "--parallel"} \
+      ${optionalString enableDebug "-Dorg.gradle.debug=true"} \
+      ${optionalString (buildJdk != null) "-Dorg.gradle.java.home=${buildJdk.home}"} \
+      --init-script ${initScript} \
+      ${concatStringsSep " " gradleFlags}
+    )
+
+    runHook postBuild
+  '';
+
+  passthru = (args.passthru or {}) // {
+    inherit offlineRepo;
+  };
+
+} // (removeAttrs args [
+  "nativeBuildInputs"
+  "passthru"
+  "lockFile"
+  "gradleFlags"
+  "gradle"
+  "enableDebug"
+  "extraInit"
+  "buildJdk"
+  "fetchers"
+]))

app/src/main/kotlin/org/nixos/gradle2nix/Main.kt

@@ -2,7 +2,7 @@ package org.nixos.gradle2nix
 
 import com.github.ajalt.clikt.core.CliktCommand
 import com.github.ajalt.clikt.core.context
-import com.github.ajalt.clikt.output.CliktHelpFormatter
+import com.github.ajalt.clikt.output.MordantHelpFormatter
 import com.github.ajalt.clikt.parameters.arguments.argument
 import com.github.ajalt.clikt.parameters.arguments.multiple
 import com.github.ajalt.clikt.parameters.options.default
@@ -10,7 +10,6 @@ import com.github.ajalt.clikt.parameters.options.flag
 import com.github.ajalt.clikt.parameters.options.multiple
 import com.github.ajalt.clikt.parameters.options.option
 import com.github.ajalt.clikt.parameters.options.validate
-import com.github.ajalt.clikt.parameters.types.choice
 import com.github.ajalt.clikt.parameters.types.enum
 import com.github.ajalt.clikt.parameters.types.file
 import java.io.File
@@ -69,14 +68,20 @@ class Gradle2Nix : CliktCommand(
         help = "Path to write generated files (default: PROJECT-DIR)")
         .file(canBeFile = false, canBeDir = true)
 
-    val envFile: String by option(
-        "--env", "-e",
+    val lockFile: String by option(
+        "--lock-file", "-l",
         metavar = "FILENAME",
-        help = "Prefix for environment files (.json and .nix)")
-        .default("gradle-env")
+        help = "Name of the generated lock file"
+    ).default("gradle.lock")
+
+    val nixFile: String by option(
+        "--nix-file", "-n",
+        metavar = "FILENAME",
+        help = "Name of the generated Nix file"
+    ).default("gradle.nix")
 
     private val logLevel: LogLevel by option(
-        "--log", "-l",
+        "--log",
         metavar = "LEVEL",
         help = "Print messages with priority of at least LEVEL")
         .enum<LogLevel>()
@@ -118,22 +123,20 @@ class Gradle2Nix : CliktCommand(
 
     init {
         context {
-            helpFormatter = CliktHelpFormatter(showDefaultValues = true)
+            helpFormatter = { MordantHelpFormatter(it, showDefaultValues = true) }
         }
     }
 
     @OptIn(ExperimentalSerializationApi::class)
     override fun run() {
-        val appHome = System.getProperty("org.nixos.gradle2nix.share")
-        if (appHome == null) {
-            System.err.println("Error: could not locate the /share directory in the gradle2nix installation")
-        }
-        val gradleHome =
-            System.getenv("GRADLE_USER_HOME")?.let(::File) ?: File("${System.getProperty("user.home")}/.gradle")
         val logger = Logger(logLevel = logLevel, stacktrace = stacktrace)
 
+        val appHome = System.getProperty("org.nixos.gradle2nix.share")?.let(::File)
+            ?: error("could not locate the /share directory in the gradle2nix installation")
+        val gradleHome =
+            System.getenv("GRADLE_USER_HOME")?.let(::File) ?: File("${System.getProperty("user.home")}/.gradle")
         val config = Config(
-            File(appHome),
+            appHome,
             gradleHome,
             gradleVersion,
             gradleJdk,
@@ -156,6 +159,8 @@ class Gradle2Nix : CliktCommand(
             } else {
                 metadata.deleteOnExit()
             }
+        } else {
+            metadata.deleteOnExit()
         }
 
         val buildSrcs = connect(config).use { connection ->
@@ -187,11 +192,19 @@ class Gradle2Nix : CliktCommand(
             logger.error("dependency parsing failed", e)
         }
 
-        val json = config.outDir.resolve("$envFile.json")
-        logger.info("Writing environment to $json")
-        json.outputStream().buffered().use { output ->
+        config.outDir.mkdirs()
+
+        val outLockFile = config.outDir.resolve(lockFile)
+        logger.info("Writing lock file to $outLockFile")
+        outLockFile.outputStream().buffered().use { output ->
             JsonFormat.encodeToStream(env, output)
         }
+
+        val inNixFile = config.appHome.resolve("gradle.nix").takeIf { it.exists() }
+            ?: error("Couldn't locate gradle.nix in the the gradle2nix installation: ${config.appHome}")
+        val outNixFile = config.outDir.resolve(nixFile)
+        logger.info("Writing Nix builder to $outNixFile")
+        inNixFile.copyTo(outNixFile, overwrite = true)
     }
 }
 

default.nix

@@ -3,10 +3,12 @@
 with pkgs;
 
 let
-  buildGradle = callPackage ./gradle-env.nix {};
+  buildGradle = callPackage ./gradle.nix {};
 
   gradle2nix = buildGradle {
-    envSpec = ./gradle-env.json;
+    pname = "gradle2nix";
+    version = "2.0.0";
+    lockFile = ./gradle.lock;
 
     src = lib.cleanSourceWith {
       filter = lib.cleanSourceFilter;
@@ -35,7 +37,4 @@ let
     };
   };
 
-in buildGradle {
-  envSpec = ./gradle-env.json;
-  pname = "gradle2nix";
-}
+in gradle2nix

flake.lock

@@ -1,15 +1,29 @@
 {
   "nodes": {
+    "flake-compat": {
+      "locked": {
+        "lastModified": 1696426674,
+        "narHash": "sha256-kvjfFW7WAETZlt09AgDn1MrtKzP7t90Vf7vypd3OL1U=",
+        "rev": "0f9255e01c2351cc7d116c072cb317785dd33b33",
+        "revCount": 57,
+        "type": "tarball",
+        "url": "https://api.flakehub.com/f/pinned/edolstra/flake-compat/1.0.1/018afb31-abd1-7bff-a5e4-cff7e18efb7a/source.tar.gz"
+      },
+      "original": {
+        "type": "tarball",
+        "url": "https://flakehub.com/f/edolstra/flake-compat/1.tar.gz"
+      }
+    },
     "flake-utils": {
       "inputs": {
         "systems": "systems"
       },
       "locked": {
-        "lastModified": 1701680307,
-        "narHash": "sha256-kAuep2h5ajznlPMD9rnQyffWG8EM/C73lejGofXvdM8=",
+        "lastModified": 1710146030,
+        "narHash": "sha256-SZ5L6eA7HJ/nmkzGG7/ISclqe6oZdOZTNoesiInkXPQ=",
         "owner": "numtide",
         "repo": "flake-utils",
-        "rev": "4022d587cbbfd70fe950c1e2083a02621806a725",
+        "rev": "b1d9ab70662946ef0850d488da1c9019f3a9752a",
         "type": "github"
       },
       "original": {
@@ -20,11 +34,11 @@
     },
     "nixpkgs": {
       "locked": {
-        "lastModified": 1702855317,
-        "narHash": "sha256-5EXeUkoWvrfbZQQLVRn7Ebb9LOt3DkVm6T0M31/VhtM=",
+        "lastModified": 1715954240,
+        "narHash": "sha256-eC0zRYkazBc2cKz1VSzMLvCc9uHXlSQEr1Be+c5UV1w=",
         "owner": "NixOS",
         "repo": "nixpkgs",
-        "rev": "3a16c6447466f4034c2d75fe7014477142c9513e",
+        "rev": "c2ea18b50a4c7fcb7c90402166769bf3b82b5aa9",
         "type": "github"
       },
       "original": {
@@ -36,6 +50,7 @@
     },
     "root": {
       "inputs": {
+        "flake-compat": "flake-compat",
         "flake-utils": "flake-utils",
         "nixpkgs": "nixpkgs"
       }

flake.nix

@@ -2,20 +2,25 @@
   description = "Wrap Gradle builds with Nix";
 
   inputs = {
+    flake-compat.url = "https://flakehub.com/f/edolstra/flake-compat/1.tar.gz";
     flake-utils.url = "github:numtide/flake-utils";
     nixpkgs.url = "github:NixOS/nixpkgs/nixos-unstable-small";
   };
 
-  outputs = { self, flake-utils, nixpkgs }:
+  outputs = { self, flake-utils, nixpkgs, ... }:
     flake-utils.lib.eachDefaultSystem (system:
-      let pkgs = nixpkgs.legacyPackages.${system};
-      in rec {
-        packages.gradle2nix = import ./default.nix { inherit pkgs; };
-        defaultPackage = packages.gradle2nix;
+      let
+        pkgs = nixpkgs.legacyPackages.${system};
+        buildGradle = pkgs.callPackage ./gradle.nix {};
+
+      in {
+        packages.default = pkgs.callPackage ./gradle2nix.nix {
+          inherit buildGradle;
+        };
 
         apps.default = {
           type = "app";
-          program = "${packages.gradle2nix}/bin/gradle2nix";
+          program = "${self.packages.gradle2nix}/bin/gradle2nix";
         };
       });
 }

gradle-env.nix

@@ -1,453 +0,0 @@
-# This file is generated by gradle2nix.
-#
-# Example usage (e.g. in default.nix):
-#
-#     with (import <nixpkgs> {});
-#     let
-#       buildGradle = callPackage ./gradle-env.nix {};
-#     in
-#       buildGradle {
-#         envSpec = ./gradle-env.json;
-#
-#         src = ./.;
-#
-#         gradleFlags = [ "installDist" ];
-#
-#         installPhase = ''
-#           mkdir -p $out
-#           cp -r app/build/install/myproject $out
-#         '';
-#       }
-
-{ lib
-, stdenv
-, buildEnv
-, fetchs3
-, fetchurl
-, gradleGen
-, maven
-, runCommandLocal
-, symlinkJoin
-, writeText
-, writeTextDir
-}:
-
-{
-  # Path to the environment spec generated by gradle2nix (e.g. gradle-env.json).
-  envSpec
-, pname ? "project"
-, version ? null
-, enableParallelBuilding ? true
-# Arguments to Gradle used to build the project in buildPhase.
-, gradleFlags ? [ "build" ]
-# Gradle package to use instead of the one generated by gradle2nix.
-, gradlePackage ? null
-# Enable debugging for the Gradle build; this will cause Gradle to run a debug server
-# and wait for a JVM debugging client to attach.
-, enableDebug ? false
-# Additional code to run in the Gradle init script (init.gradle).
-, extraInit ? ""
-# Override the default JDK used to run Gradle itself.
-, buildJdk ? null
-# Override functions which fetch dependency artifacts.
-# Keys in this set are URL schemes such as "https" or "s3".
-# Values are functions which take a dependency in the form
-# `{ urls, sha256 }` and fetch into the Nix store. For example:
-#
-#   {
-#     s3 = { name, urls, hash }: fetchs3 {
-#       s3url = builtins.head urls;
-#       # TODO This doesn't work without patching fetchs3 to accept SRI hashes
-#       inherit name hash;
-#       region = "us-west-2";
-#       credentials = {
-#         access_key_id = "foo";
-#         secret_access_key = "bar";
-#       };
-#     };
-#   }
-, fetchers ? { }
-, ... } @ args:
-
-let
-  inherit (builtins)
-    attrValues concatStringsSep elemAt filter fromJSON getAttr hasAttr head length match
-    replaceStrings sort;
-
-  inherit (lib)
-    assertMsg concatMapStringsSep foldl' groupBy' hasSuffix hasPrefix last mapAttrs
-    mapAttrsToList optionalAttrs optionalString readFile removeSuffix unique versionAtLeast
-    versionOlder;
-
-  inherit (lib.strings) sanitizeDerivationName;
-
-  toCoordinates = id:
-    let
-      coords = builtins.split ":" id;
-    in {
-      group = elemAt coords 0;
-      module = elemAt coords 2;
-    };
-
-  parseVersion = version:
-    let
-      parts = builtins.split ":" version;
-      base = elemAt parts 0;
-    in
-      {
-        inherit base;
-        exact = base;
-      }
-      // optionalAttrs (length parts >= 2) (
-        let
-          snapshot = elemAt parts 2;
-          exact = replaceStrings [ "-SNAPSHOT" ] [ "-${snapshot}" ] base;
-          parts = builtins.split "-" timestamp;
-          timestamp = findFirst (match "[0-9]{8}\.[0-9]{6}") parts;
-          buildNumber = let lastPart = last parts; in if match "[0-9]+" lastPart then lastPart else null;
-        in
-          { inherit snapshot exact timestamp buildNumber; }
-      );
-
-  snapshotVersion = { revision, snapshot ? null, ... }:
-    if snapshot == null
-    then revision
-    else replaceStrings ["SNAPSHOT"] [snapshot] revision;
-
-  fetchers' = {
-    http = fetchurl;
-    https = fetchurl;
-  } // fetchers;
-
-  # Fetch urls using the scheme for the first entry only; there isn't a
-  # straightforward way to tell Nix to try multiple fetchers in turn
-  # and short-circuit on the first successful fetch.
-  fetch = _: { urls, hash }:
-    let
-      first = head urls;
-      scheme = head (builtins.match "([a-z0-9+.-]+)://.*" first);
-      fetch' = getAttr scheme fetchers';
-      urls' = filter (hasPrefix scheme) urls;
-    in
-      fetch' { urls = urls'; inherit hash; };
-
-  mkModuleMetadata = deps:
-    let
-      metadata = group: module: versions:
-        let
-          latest = foldl'
-            (l: v: if l == null || versionOlder l v then v else l)
-            null
-            versions;
-
-          release = foldl'
-            (l: v: if !(hasSuffix "-SNAPSHOT" v) && (l == null || versionOlder l v) then v else l)
-            null
-            versions;
-
-          path = "${replaceStrings ["."] ["/"] group}/${module}/maven-metadata.xml";
-
-        in
-          writeTextDir path ''
-            <?xml version="1.0" encoding="UTF-8"?>
-            <metadata modelVersion="1.1">
-              <groupId>${group}</groupId>
-              <artifactId>${module}</artifactId>
-              <versioning>
-                ${optionalString (latest != null) "<latest>${latest}</latest>"}
-                ${optionalString (release != null) "<release>${release}</release>"}
-                <versions>
-                  ${concatMapStringsSep "\n      " (v: "<version>${v}</version>") versions}
-                </versions>
-              </versioning>
-            </metadata>
-          '';
-
-      groupedModules = groupBy
-        ({ organisation, module, ... }: "${organisation}:${module}")
-        (mapAttrsToList (_: dep: dep.attrs) deps);
-
-    in
-      map
-
-
-  # mkSnapshotMetadata = { group, module }: version: artifacts:
-  #   let
-  #     versions' = filter (hasAttr "timestamp") versions;
-
-
-  #   in
-  #     map ({ base, exact, snapshot, timestamp, buildNumber }:
-
-  #     ) versions';
-
-  mkModule = { attrs, artifacts }:
-    let
-      modulePath = "${replaceStrings ["."] ["/"] attrs.orgPath}/${attrs.module}/${attrs.revision}";
-    in
-      stdenv.mkDerivation {
-        pname = "${attrs.group}-${attrs.module}";
-        version = snapshotVersion attrs.revision;
-
-        srcs = mapAttrsToList fetch artifacts;
-
-        dontPatch = true;
-        dontConfigure = true;
-        dontBuild = true;
-        dontFixup = true;
-        dontInstall = true;
-
-        preUnpack = ''
-          mkdir -p "$out/${modulePath}"
-        '';
-
-        unpackCmd = ''
-          cp "$curSrc" "$out/${modulePath}/$(stripHash "$curSrc")"
-        '';
-
-        sourceRoot = ".";
-
-        preferLocalBuild = true;
-        allowSubstitutes = false;
-      };
-
-  mkModules = deps:
-    mapAttrsToList (_: m: mkModule m) deps;
-
-  # mkSnapshotMetadata = deps:
-  #   let
-  #     snapshotDeps = filter (dep: dep ? build && dep ? timestamp) deps;
-
-  #     modules = groupBy'
-  #       (meta: dep:
-  #         let
-  #           id = dep.id;
-  #           isNewer = dep.build > meta.buildNumber;
-  #           # Timestamp values can be bogus, e.g. jitpack.io
-  #           updated = if (match "[0-9]{8}\.[0-9]{6}" dep.timestamp) != null
-  #                     then replaceStrings ["."] [""] dep.timestamp
-  #                     else "";
-  #         in {
-  #           groupId = id.group;
-  #           artifactId = id.name;
-  #           version = id.version;
-  #           timestamp = if isNewer then dep.timestamp else meta.timestamp;
-  #           buildNumber = if isNewer then dep.build else meta.buildNumber;
-  #           lastUpdated = if isNewer then updated else meta.lastUpdated;
-  #           versions = meta.versions or [] ++ [{
-  #             classifier = id.classifier or "";
-  #             extension = id.extension;
-  #             value = "${removeSuffix "-SNAPSHOT" id.version}-${dep.timestamp}-${toString dep.build}";
-  #             updated = updated;
-  #           }];
-  #         }
-  #       )
-  #       {
-  #         timestamp = "";
-  #         buildNumber = -1;
-  #         lastUpdated = "";
-  #       }
-  #       (dep: "${replaceStrings ["."] ["/"] dep.id.group}/${dep.id.name}/${dep.id.version}/maven-metadata.xml")
-  #       snapshotDeps;
-
-  #     mkSnapshotVersion = version: ''
-  #       <snapshotVersion>
-  #         ${optionalString (version.classifier != "") "<classifier>${version.classifier}</classifier>"}
-  #         <extension>${version.extension}</extension>
-  #         <value>${version.value}</value>
-  #         ${optionalString (version.updated != "") "<updated>${version.updated}</updated>"}
-  #       </snapshotVersion>
-  #     '';
-
-  #   in
-  #     attrValues (mapAttrs (path: meta:
-  #       with meta; writeTextDir path ''
-  #         <?xml version="1.0" encoding="UTF-8"?>
-  #         <metadata modelVersion="1.1">
-  #           <groupId>${groupId}</groupId>
-  #           <artifactId>${artifactId}</artifactId>
-  #           <version>${version}</version>
-  #           <versioning>
-  #             <snapshot>
-  #               ${optionalString (timestamp != "") "<timestamp>${timestamp}</timestamp>"}
-  #               ${optionalString (buildNumber != -1) "<buildNumber>${toString buildNumber}</buildNumber>"}
-  #             </snapshot>
-  #             ${optionalString (lastUpdated != "") "<lastUpdated>${lastUpdated}</lastUpdated>"}
-  #             <snapshotVersions>
-  #               ${concatMapStringsSep "\n    " mkSnapshotVersion versions}
-  #             </snapshotVersions>
-  #           </versioning>
-  #         </metadata>
-  #       ''
-  #     ) modules);
-
-  mkRepo = name: deps: symlinkJoin {
-    name = "${name}-gradle-repo";
-    paths = mkModules deps ++ mkModuleMetadata deps ++ mkSnapshotMetadata deps;
-  };
-
-  mkInitScript = projectSpec: gradle:
-    let
-      repos = mapAttrs (mkRepo projectSpec.name) projectSpec.dependencies;
-      hasDependencies = mapAttrs (type: deps: deps != []) projectSpec.dependencies;
-
-      inSettings = pred: script:
-        optionalString pred (
-          if versionAtLeast gradle.version "6.0" then ''
-            gradle.beforeSettings {
-              ${script}
-            }
-          '' else ''
-            gradle.settingsEvaluated {
-              ${script}
-            }
-          ''
-        );
-    in
-      assert (assertMsg (hasDependencies.settings -> versionAtLeast gradle.version "6.0") ''
-        Project `${projectSpec.name}' has settings script dependencies, such as settings
-        plugins, which are not supported by gradle2nix for Gradle versions prior to 6.0.
-
-        Potential remedies:
-        - Pass `--gradle-version=<version>' to the gradle2nix command.
-        - Patch the `settings.gradle[.kts]' file to remove script dependencies.
-      '');
-
-      writeText "init.gradle" ''
-        static def offlineRepo(RepositoryHandler repositories, String env, String path) {
-            repositories.clear()
-            repositories.maven {
-                name "Nix''${env.capitalize()}Offline"
-                url path
-                metadataSources {
-                    it.gradleMetadata()
-                    it.mavenPom()
-                    it.
-                }
-            }
-            repositories.ivy {
-                name "Nix''${env.capitalize()}IvyOffline"
-                url path
-                layout "maven"
-                metadataSources {
-                    it.gradleMetadata()
-                    it.ivyDescriptor()
-                }
-            }
-        }
-
-        ${inSettings (hasDependencies.settings && (versionAtLeast gradle.version "6.0")) ''
-          offlineRepo(it.buildscript.repositories, "settings", "${repos.settings}")
-        ''}
-
-        ${inSettings (hasDependencies.plugin) ''
-            offlineRepo(it.pluginManagement.repositories, "plugin", "${repos.plugin}")
-        ''}
-
-        ${optionalString (hasDependencies.buildscript) ''
-          gradle.projectsLoaded {
-              allprojects {
-                  buildscript {
-                      offlineRepo(repositories, "buildscript", "${repos.buildscript}")
-                  }
-              }
-          }
-        ''}
-
-        ${optionalString (hasDependencies.project) (
-          if versionAtLeast gradle.version "6.8"
-          then ''
-            gradle.beforeSettings {
-                it.dependencyResolutionManagement {
-                    offlineRepo(repositories, "project", "${repos.project}")
-                    repositoriesMode.set(RepositoriesMode.PREFER_SETTINGS)
-                }
-            }
-          ''
-          else ''
-            gradle.projectsLoaded {
-                allprojects {
-                    offlineRepo(repositories, "project", "${repos.project}")
-                }
-            }
-          ''
-        )}
-
-        ${extraInit}
-      '';
-
-  mkGradle = gradleSpec:
-    gradleGen.gradleGen {
-      inherit (gradleSpec) nativeVersion;
-
-      name = "gradle-${gradleSpec.version}-${gradleSpec.type}";
-
-      src = fetchurl {
-        inherit (gradleSpec) url sha256;
-      };
-    } // {
-      inherit (gradleSpec) version;
-    };
-
-  mkProjectEnv = projectSpec: rec {
-    inherit (projectSpec) name path version;
-    gradle = args.gradlePackage or mkGradle projectSpec.gradle;
-    initScript = mkInitScript projectSpec gradle;
-  };
-
-  gradleEnv = mapAttrs
-    (_: p: mkProjectEnv p)
-    (fromJSON (readFile envSpec));
-
-  projectEnv = gradleEnv."";
-  pname = args.pname or projectEnv.name;
-  version = args.version or projectEnv.version;
-
-  buildProject = env: flags: ''
-    cp ${env.initScript} "$GRADLE_USER_HOME/init.d"
-
-    gradle --offline --no-daemon --no-build-cache \
-      --info --full-stacktrace --warning-mode=all \
-      ${optionalString enableParallelBuilding "--parallel"} \
-      ${optionalString enableDebug "-Dorg.gradle.debug=true"} \
-      ${optionalString (buildJdk != null) "-Dorg.gradle.java.home=${buildJdk.home}"} \
-      --init-script ${env.initScript} \
-      ${optionalString (env.path != "") ''-p "${env.path}"''} \
-      ${concatStringsSep " " flags}
-  '';
-
-  buildIncludedProjects =
-    concatStringsSep "\n" (mapAttrsToList
-      (_: env: buildProject env [ "build" ])
-      (removeAttrs gradleEnv [ "" ]));
-
-  buildRootProject = buildProject projectEnv gradleFlags;
-
-  # in stdenv.mkDerivation (args // {
-
-  #   inherit pname version;
-
-  #   nativeBuildInputs = (args.nativeBuildInputs or []) ++ [ projectEnv.gradle ];
-
-  #   buildPhase = args.buildPhase or ''
-  #     runHook preBuild
-
-  #     (
-  #     set -eux
-
-  #     # Work around https://github.com/gradle/gradle/issues/1055
-  #     TMPHOME="$(mktemp -d)"
-  #     mkdir -p "$TMPHOME/init.d"
-  #     export GRADLE_USER_HOME="$TMPHOME"
-
-  #     ${buildIncludedProjects}
-  #     ${buildRootProject}
-  #     )
-
-  #     runHook postBuild
-  #   '';
-
-  #   dontStrip = true;
-  # })
-
-in mkRepo pname (fromJSON (readFile envSpec))

gradle.nix

@@ -0,0 +1,292 @@
+# This file is generated by gradle2nix.
+#
+# Example usage (e.g. in default.nix):
+#
+#     with (import <nixpkgs> {});
+#     let
+#       buildGradle = callPackage ./gradle.nix {};
+#     in
+#       buildGradle {
+#         lockFile = ./gradle.lock;
+#
+#         src = ./.;
+#
+#         gradleFlags = [ "installDist" ];
+#
+#         installPhase = ''
+#           mkdir -p $out
+#           cp -r app/build/install/myproject $out
+#         '';
+#       }
+
+{ lib
+, stdenv
+, buildEnv
+, fetchs3
+, fetchurl
+, gradle
+, maven
+, runCommandLocal
+, symlinkJoin
+, writeText
+, writeTextDir
+}:
+
+{
+  # Path to the lockfile generated by gradle2nix (e.g. gradle.lock).
+  lockFile
+, pname ? "project"
+, version ? null
+, enableParallelBuilding ? true
+# Arguments to Gradle used to build the project in buildPhase.
+, gradleFlags ? [ "build" ]
+# Enable debugging for the Gradle build; this will cause Gradle to run a debug server
+# and wait for a JVM debugging client to attach.
+, enableDebug ? false
+# Additional code to run in the Gradle init script (init.gradle).
+, extraInit ? ""
+# Override the default JDK used to run Gradle itself.
+, buildJdk ? null
+# Override functions which fetch dependency artifacts.
+# Keys in this set are URL schemes such as "https" or "s3".
+# Values are functions which take a dependency in the form
+# `{ urls, hash }` and fetch into the Nix store. For example:
+#
+#   {
+#     s3 = { name, urls, hash }: fetchs3 {
+#       s3url = builtins.head urls;
+#       # TODO This doesn't work without patching fetchs3 to accept SRI hashes
+#       inherit name hash;
+#       region = "us-west-2";
+#       credentials = {
+#         access_key_id = "foo";
+#         secret_access_key = "bar";
+#       };
+#     };
+#   }
+, fetchers ? { }
+, ... } @ args:
+
+let
+  inherit (builtins)
+    attrValues concatStringsSep elemAt filter fromJSON getAttr hasAttr head length match
+    removeAttrs replaceStrings sort;
+
+  inherit (lib)
+    assertMsg concatMapStringsSep findFirst foldl' groupBy' hasSuffix hasPrefix last mapAttrs
+    mapAttrsToList optionalAttrs optionalString readFile removeSuffix unique versionAtLeast
+    versionOlder;
+
+  inherit (lib.strings) sanitizeDerivationName;
+
+  lockedDeps = fromJSON (readFile lockFile);
+
+  toCoordinates = id:
+    let
+      coords = builtins.split ":" id;
+    in rec {
+      group = elemAt coords 0;
+      module = elemAt coords 2;
+      version = elemAt coords 4;
+      versionParts = parseVersion version;
+    };
+
+  parseVersion = version:
+    let
+      parts = builtins.split ":" version;
+      base = elemAt parts 0;
+    in
+      {
+        inherit base;
+        exact = base;
+      }
+      // optionalAttrs (length parts >= 2) (
+        let
+          snapshot = elemAt parts 2;
+          exact = replaceStrings [ "-SNAPSHOT" ] [ "-${snapshot}" ] base;
+          parts = builtins.split "-" timestamp;
+          timestamp = findFirst (match "[0-9]{8}\.[0-9]{6}") parts;
+          buildNumber = let lastPart = last parts; in if match "[0-9]+" lastPart then lastPart else null;
+        in
+          { inherit snapshot exact timestamp buildNumber; }
+      );
+
+  fetchers' = {
+    http = fetchurl;
+    https = fetchurl;
+  } // fetchers;
+
+  # Fetch urls using the scheme for the first entry only; there isn't a
+  # straightforward way to tell Nix to try multiple fetchers in turn
+  # and short-circuit on the first successful fetch.
+  fetch = name: { urls, hash }:
+    let
+      first = head urls;
+      scheme = head (builtins.match "([a-z0-9+.-]+)://.*" first);
+      fetch' = getAttr scheme fetchers';
+      urls' = filter (hasPrefix scheme) urls;
+    in
+      fetch' { urls = urls'; inherit hash; };
+
+  mkModule = id: artifacts:
+    let
+      coords = toCoordinates id;
+      modulePath = "${replaceStrings ["."] ["/"] coords.group}/${coords.module}/${coords.version}";
+    in
+      stdenv.mkDerivation {
+        pname = sanitizeDerivationName "${coords.group}-${coords.module}";
+        version = coords.versionParts.exact;
+
+        srcs = mapAttrsToList fetch artifacts;
+
+        dontPatch = true;
+        dontConfigure = true;
+        dontBuild = true;
+        dontFixup = true;
+        dontInstall = true;
+
+        preUnpack = ''
+          mkdir -p "$out/${modulePath}"
+        '';
+
+        unpackCmd = ''
+          cp "$curSrc" "$out/${modulePath}/$(stripHash "$curSrc")"
+        '';
+
+        sourceRoot = ".";
+
+        preferLocalBuild = true;
+        allowSubstitutes = false;
+      };
+
+  offlineRepo = symlinkJoin {
+    name = if version != null then "${pname}-${version}-gradle-repo" else "${pname}-gradle-repo";
+    paths = mapAttrsToList mkModule lockedDeps;
+  };
+
+  initScript =
+    let
+      inSettings = pred: script:
+        optionalString pred (
+          if versionAtLeast gradle.version "6.0" then ''
+            gradle.beforeSettings {
+              ${script}
+            }
+          '' else ''
+            gradle.settingsEvaluated {
+              ${script}
+            }
+          ''
+        );
+    in
+      writeText "init.gradle" ''
+        static def offlineRepo(RepositoryHandler repositories) {
+            repositories.clear()
+            repositories.mavenLocal {
+                url 'file:${offlineRepo}'
+                metadataSources {
+                    gradleMetadata()
+                    mavenPom()
+                    artifact()
+                }
+            }
+        }
+
+        ${inSettings (versionAtLeast gradle.version "6.0") ''
+          offlineRepo(it.buildscript.repositories)
+        ''}
+
+        ${inSettings true ''
+            offlineRepo(it.pluginManagement.repositories)
+        ''}
+
+        gradle.projectsLoaded {
+            allprojects {
+                buildscript {
+                    offlineRepo(repositories)
+                }
+            }
+        }
+
+        ${if versionAtLeast gradle.version "6.8"
+          then ''
+            gradle.beforeSettings {
+                it.dependencyResolutionManagement {
+                    offlineRepo(repositories)
+                    repositoriesMode.set(RepositoriesMode.PREFER_SETTINGS)
+                }
+            }
+          ''
+          else ''
+            gradle.projectsLoaded {
+                allprojects {
+                    offlineRepo(repositories)
+                }
+            }
+          ''
+        }
+
+        ${extraInit}
+      '';
+
+  buildProject = flags: ''
+    gradle --offline --no-daemon --no-build-cache \
+      --info --full-stacktrace --warning-mode=all \
+      --no-configuration-cache \
+      -Dmaven.repo.local=${offlineRepo} \
+      ${optionalString enableParallelBuilding "--parallel"} \
+      ${optionalString enableDebug "-Dorg.gradle.debug=true"} \
+      ${optionalString (buildJdk != null) "-Dorg.gradle.java.home=${buildJdk.home}"} \
+      --init-script ${initScript} \
+      ${concatStringsSep " " flags}
+  '';
+
+in stdenv.mkDerivation ({
+
+  dontStrip = true;
+
+  nativeBuildInputs = (args.nativeBuildInputs or []) ++ [ gradle ];
+
+  buildPhase = args.buildPhase or ''
+    runHook preBuild
+
+    (
+    set -eux
+
+    ${optionalString (versionOlder gradle.version "8.0") ''
+      # Work around https://github.com/gradle/gradle/issues/1055
+      TMPHOME="$(mktemp -d)"
+      mkdir -p "$TMPHOME/init.d"
+      export GRADLE_USER_HOME="$TMPHOME"
+      cp ${initScript} $TMPHOME/
+    ''}
+
+    gradle --offline --no-daemon --no-build-cache \
+      --info --full-stacktrace --warning-mode=all \
+      --no-configuration-cache --console=plain \
+      -Dmaven.repo.local=${offlineRepo} \
+      ${optionalString enableParallelBuilding "--parallel"} \
+      ${optionalString enableDebug "-Dorg.gradle.debug=true"} \
+      ${optionalString (buildJdk != null) "-Dorg.gradle.java.home=${buildJdk.home}"} \
+      --init-script ${initScript} \
+      ${concatStringsSep " " gradleFlags}
+    )
+
+    runHook postBuild
+  '';
+
+  passthru = (args.passthru or {}) // {
+    inherit offlineRepo;
+  };
+
+} // (removeAttrs args [
+  "nativeBuildInputs"
+  "passthru"
+  "lockFile"
+  "gradleFlags"
+  "gradle"
+  "enableDebug"
+  "extraInit"
+  "buildJdk"
+  "fetchers"
+]))

gradle/libs.versions.toml

@@ -1,21 +1,19 @@
 [versions]
 gradle = "8.7"
+junit = "5.8.2"
 kotlin = "1.9.22"
 ktor = "2.3.11"
+kotest = "5.9.0"
 
 [libraries]
-clikt = "com.github.ajalt:clikt:+"
+clikt = "com.github.ajalt.clikt:clikt:4.4.0"
 gradle-toolingApi = { module = "org.gradle:gradle-tooling-api", version.ref = "gradle" }
-junit-jupiter-api = "org.junit.jupiter:junit-jupiter-api:+"
-junit-jupiter-engine = "org.junit.jupiter:junit-jupiter-engine:+"
-junit-jupiter-params = "org.junit.jupiter:junit-jupiter-params:+"
-junit-platformLauncher = "org.junit.platform:junit-platform-launcher:+"
-kotest-runner = "io.kotest:kotest-runner-junit5:+"
-kotest-assertions = "io.kotest:kotest-assertions-core:+"
-kotlinx-coroutines-core = "org.jetbrains.kotlinx:kotlinx-coroutines-core:+"
+kotest-assertions = { module = "io.kotest:kotest-assertions-core", version.ref = "kotest" }
+kotest-runner = { module = "io.kotest:kotest-runner-junit5", version.ref = "kotest" }
+kotlinx-coroutines-core = "org.jetbrains.kotlinx:kotlinx-coroutines-core:1.8.1"
 ktor-server-core = { module = "io.ktor:ktor-server-core", version.ref = "ktor" }
 ktor-server-netty = { module = "io.ktor:ktor-server-netty", version.ref = "ktor" }
-okio = "com.squareup.okio:okio:+"
+okio = "com.squareup.okio:okio:3.9.0"
 serialization-json = "org.jetbrains.kotlinx:kotlinx-serialization-json:1.6.3"
 slf4j-api = "org.slf4j:slf4j-api:+"
 slf4j-simple = "org.slf4j:slf4j-simple:+"

gradle2nix.nix

@@ -0,0 +1,41 @@
+{ lib
+, gradle
+, buildGradle
+}:
+
+buildGradle {
+  pname = "gradle2nix";
+  version = "2.0.0";
+  lockFile = ./gradle.lock;
+
+  src = lib.cleanSourceWith {
+      filter = lib.cleanSourceFilter;
+      src = lib.cleanSourceWith {
+          filter = path: type: let baseName = builtins.baseNameOf path; in !(
+          (type == "directory" && (
+                  baseName == "build" ||
+                          baseName == ".idea" ||
+                          baseName == ".gradle"
+                  )) ||
+                  (lib.hasSuffix ".iml" baseName)
+          );
+          src = ./.;
+      };
+  };
+
+  gradleFlags = [ "installDist" ];
+
+  installPhase = ''
+    mkdir -p $out
+    cp -r app/build/install/gradle2nix/* $out/
+  '';
+
+  meta = with lib; {
+    inherit (gradle.meta) platforms;
+    description = "Wrap Gradle builds with Nix";
+    homepage = "https://github.com/tadfisher/gradle2nix";
+    license = licenses.asl20;
+    maintainers = with maintainers; [ tadfisher ];
+    mainProgram = "gradle2nix";
+  };
+}