Initial commit.

.gitattributes

@@ -0,0 +1,5 @@
+#
+# https://help.github.com/articles/dealing-with-line-endings/
+#
+# These are explicitly windows files and should use crlf
+*.bat           text eol=crlf

.gitignore

@@ -0,0 +1,8 @@
+# Ignore Gradle project-specific cache directory
+.gradle
+
+# Ignore Gradle build output directory
+build
+
+# IntelliJ IDEA
+.idea/

build.gradle.kts

@@ -0,0 +1,48 @@
+plugins {
+  `kotlin-dsl`
+  kotlin("plugin.serialization") version "1.6.21"
+
+  id("maven-publish")
+  id("java-gradle-plugin")
+}
+
+group = "lgbt.mystic.foundation"
+version = "0.1.0"
+
+repositories {
+  mavenCentral()
+  gradlePluginPortal()
+}
+
+dependencies {
+  implementation("org.jetbrains.kotlin:kotlin-gradle-plugin:1.6.21")
+  implementation("org.jetbrains.kotlin:kotlin-serialization:1.6.21")
+  implementation("gradle.plugin.com.github.johnrengelman:shadow:7.1.2")
+  implementation("com.google.code.gson:gson:2.9.0")
+
+  // TODO: What uses this?
+  implementation("org.bouncycastle:bcprov-jdk15on:1.70")
+}
+
+gradlePlugin {
+  plugins {
+    create("concrete") {
+      id = "lgbt.mystic.foundation.concrete"
+      implementationClass = "lgbt.mystic.foundation.concrete.ConcreteGradlePlugin"
+    }
+  }
+}
+
+publishing {
+  repositories {
+    mavenLocal()
+    maven {
+      name = "GitHubPackages"
+      url = uri("https://maven.pkg.github.com/mysticlgbt/concrete")
+      credentials {
+        username = project.findProperty("github.username") as String?
+        password = project.findProperty("github.token") as String?
+      }
+    }
+  }
+}

gradle/wrapper/gradle-wrapper.properties

@@ -0,0 +1,5 @@
+distributionBase=GRADLE_USER_HOME
+distributionPath=wrapper/dists
+distributionUrl=https\://services.gradle.org/distributions/gradle-7.4.2-bin.zip
+zipStoreBase=GRADLE_USER_HOME
+zipStorePath=wrapper/dists

gradlew

@@ -0,0 +1,234 @@
+#!/bin/sh
+
+#
+# Copyright © 2015-2021 the original authors.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      https://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+
+##############################################################################
+#
+#   Gradle start up script for POSIX generated by Gradle.
+#
+#   Important for running:
+#
+#   (1) You need a POSIX-compliant shell to run this script. If your /bin/sh is
+#       noncompliant, but you have some other compliant shell such as ksh or
+#       bash, then to run this script, type that shell name before the whole
+#       command line, like:
+#
+#           ksh Gradle
+#
+#       Busybox and similar reduced shells will NOT work, because this script
+#       requires all of these POSIX shell features:
+#         * functions;
+#         * expansions «$var», «${var}», «${var:-default}», «${var+SET}»,
+#           «${var#prefix}», «${var%suffix}», and «$( cmd )»;
+#         * compound commands having a testable exit status, especially «case»;
+#         * various built-in commands including «command», «set», and «ulimit».
+#
+#   Important for patching:
+#
+#   (2) This script targets any POSIX shell, so it avoids extensions provided
+#       by Bash, Ksh, etc; in particular arrays are avoided.
+#
+#       The "traditional" practice of packing multiple parameters into a
+#       space-separated string is a well documented source of bugs and security
+#       problems, so this is (mostly) avoided, by progressively accumulating
+#       options in "$@", and eventually passing that to Java.
+#
+#       Where the inherited environment variables (DEFAULT_JVM_OPTS, JAVA_OPTS,
+#       and GRADLE_OPTS) rely on word-splitting, this is performed explicitly;
+#       see the in-line comments for details.
+#
+#       There are tweaks for specific operating systems such as AIX, CygWin,
+#       Darwin, MinGW, and NonStop.
+#
+#   (3) This script is generated from the Groovy template
+#       https://github.com/gradle/gradle/blob/master/subprojects/plugins/src/main/resources/org/gradle/api/internal/plugins/unixStartScript.txt
+#       within the Gradle project.
+#
+#       You can find Gradle at https://github.com/gradle/gradle/.
+#
+##############################################################################
+
+# Attempt to set APP_HOME
+
+# Resolve links: $0 may be a link
+app_path=$0
+
+# Need this for daisy-chained symlinks.
+while
+    APP_HOME=${app_path%"${app_path##*/}"}  # leaves a trailing /; empty if no leading path
+    [ -h "$app_path" ]
+do
+    ls=$( ls -ld "$app_path" )
+    link=${ls#*' -> '}
+    case $link in             #(
+      /*)   app_path=$link ;; #(
+      *)    app_path=$APP_HOME$link ;;
+    esac
+done
+
+APP_HOME=$( cd "${APP_HOME:-./}" && pwd -P ) || exit
+
+APP_NAME="Gradle"
+APP_BASE_NAME=${0##*/}
+
+# Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script.
+DEFAULT_JVM_OPTS='"-Xmx64m" "-Xms64m"'
+
+# Use the maximum available, or set MAX_FD != -1 to use that value.
+MAX_FD=maximum
+
+warn () {
+    echo "$*"
+} >&2
+
+die () {
+    echo
+    echo "$*"
+    echo
+    exit 1
+} >&2
+
+# OS specific support (must be 'true' or 'false').
+cygwin=false
+msys=false
+darwin=false
+nonstop=false
+case "$( uname )" in                #(
+  CYGWIN* )         cygwin=true  ;; #(
+  Darwin* )         darwin=true  ;; #(
+  MSYS* | MINGW* )  msys=true    ;; #(
+  NONSTOP* )        nonstop=true ;;
+esac
+
+CLASSPATH=$APP_HOME/gradle/wrapper/gradle-wrapper.jar
+
+
+# Determine the Java command to use to start the JVM.
+if [ -n "$JAVA_HOME" ] ; then
+    if [ -x "$JAVA_HOME/jre/sh/java" ] ; then
+        # IBM's JDK on AIX uses strange locations for the executables
+        JAVACMD=$JAVA_HOME/jre/sh/java
+    else
+        JAVACMD=$JAVA_HOME/bin/java
+    fi
+    if [ ! -x "$JAVACMD" ] ; then
+        die "ERROR: JAVA_HOME is set to an invalid directory: $JAVA_HOME
+
+Please set the JAVA_HOME variable in your environment to match the
+location of your Java installation."
+    fi
+else
+    JAVACMD=java
+    which java >/dev/null 2>&1 || die "ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH.
+
+Please set the JAVA_HOME variable in your environment to match the
+location of your Java installation."
+fi
+
+# Increase the maximum file descriptors if we can.
+if ! "$cygwin" && ! "$darwin" && ! "$nonstop" ; then
+    case $MAX_FD in #(
+      max*)
+        MAX_FD=$( ulimit -H -n ) ||
+            warn "Could not query maximum file descriptor limit"
+    esac
+    case $MAX_FD in  #(
+      '' | soft) :;; #(
+      *)
+        ulimit -n "$MAX_FD" ||
+            warn "Could not set maximum file descriptor limit to $MAX_FD"
+    esac
+fi
+
+# Collect all arguments for the java command, stacking in reverse order:
+#   * args from the command line
+#   * the main class name
+#   * -classpath
+#   * -D...appname settings
+#   * --module-path (only if needed)
+#   * DEFAULT_JVM_OPTS, JAVA_OPTS, and GRADLE_OPTS environment variables.
+
+# For Cygwin or MSYS, switch paths to Windows format before running java
+if "$cygwin" || "$msys" ; then
+    APP_HOME=$( cygpath --path --mixed "$APP_HOME" )
+    CLASSPATH=$( cygpath --path --mixed "$CLASSPATH" )
+
+    JAVACMD=$( cygpath --unix "$JAVACMD" )
+
+    # Now convert the arguments - kludge to limit ourselves to /bin/sh
+    for arg do
+        if
+            case $arg in                                #(
+              -*)   false ;;                            # don't mess with options #(
+              /?*)  t=${arg#/} t=/${t%%/*}              # looks like a POSIX filepath
+                    [ -e "$t" ] ;;                      #(
+              *)    false ;;
+            esac
+        then
+            arg=$( cygpath --path --ignore --mixed "$arg" )
+        fi
+        # Roll the args list around exactly as many times as the number of
+        # args, so each arg winds up back in the position where it started, but
+        # possibly modified.
+        #
+        # NB: a `for` loop captures its iteration list before it begins, so
+        # changing the positional parameters here affects neither the number of
+        # iterations, nor the values presented in `arg`.
+        shift                   # remove old arg
+        set -- "$@" "$arg"      # push replacement arg
+    done
+fi
+
+# Collect all arguments for the java command;
+#   * $DEFAULT_JVM_OPTS, $JAVA_OPTS, and $GRADLE_OPTS can contain fragments of
+#     shell script including quotes and variable substitutions, so put them in
+#     double quotes to make sure that they get re-expanded; and
+#   * put everything else in single quotes, so that it's not re-expanded.
+
+set -- \
+        "-Dorg.gradle.appname=$APP_BASE_NAME" \
+        -classpath "$CLASSPATH" \
+        org.gradle.wrapper.GradleWrapperMain \
+        "$@"
+
+# Use "xargs" to parse quoted args.
+#
+# With -n1 it outputs one arg per line, with the quotes and backslashes removed.
+#
+# In Bash we could simply go:
+#
+#   readarray ARGS < <( xargs -n1 <<<"$var" ) &&
+#   set -- "${ARGS[@]}" "$@"
+#
+# but POSIX shell has neither arrays nor command substitution, so instead we
+# post-process each arg (as a line of input to sed) to backslash-escape any
+# character that might be a shell metacharacter, then use eval to reverse
+# that process (while maintaining the separation between arguments), and wrap
+# the whole thing up as a single "set" statement.
+#
+# This will of course break if any of these variables contains a newline or
+# an unmatched quote.
+#
+
+eval "set -- $(
+        printf '%s\n' "$DEFAULT_JVM_OPTS $JAVA_OPTS $GRADLE_OPTS" |
+        xargs -n1 |
+        sed ' s~[^-[:alnum:]+,./:=@_]~\\&~g; ' |
+        tr '\n' ' '
+    )" '"$@"'
+
+exec "$JAVACMD" "$@"

gradlew.bat

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+@rem
+@rem Copyright 2015 the original author or authors.
+@rem
+@rem Licensed under the Apache License, Version 2.0 (the "License");
+@rem you may not use this file except in compliance with the License.
+@rem You may obtain a copy of the License at
+@rem
+@rem      https://www.apache.org/licenses/LICENSE-2.0
+@rem
+@rem Unless required by applicable law or agreed to in writing, software
+@rem distributed under the License is distributed on an "AS IS" BASIS,
+@rem WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+@rem See the License for the specific language governing permissions and
+@rem limitations under the License.
+@rem
+
+@if "%DEBUG%" == "" @echo off
+@rem ##########################################################################
+@rem
+@rem  Gradle startup script for Windows
+@rem
+@rem ##########################################################################
+
+@rem Set local scope for the variables with windows NT shell
+if "%OS%"=="Windows_NT" setlocal
+
+set DIRNAME=%~dp0
+if "%DIRNAME%" == "" set DIRNAME=.
+set APP_BASE_NAME=%~n0
+set APP_HOME=%DIRNAME%
+
+@rem Resolve any "." and ".." in APP_HOME to make it shorter.
+for %%i in ("%APP_HOME%") do set APP_HOME=%%~fi
+
+@rem Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script.
+set DEFAULT_JVM_OPTS="-Xmx64m" "-Xms64m"
+
+@rem Find java.exe
+if defined JAVA_HOME goto findJavaFromJavaHome
+
+set JAVA_EXE=java.exe
+%JAVA_EXE% -version >NUL 2>&1
+if "%ERRORLEVEL%" == "0" goto execute
+
+echo.
+echo ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH.
+echo.
+echo Please set the JAVA_HOME variable in your environment to match the
+echo location of your Java installation.
+
+goto fail
+
+:findJavaFromJavaHome
+set JAVA_HOME=%JAVA_HOME:"=%
+set JAVA_EXE=%JAVA_HOME%/bin/java.exe
+
+if exist "%JAVA_EXE%" goto execute
+
+echo.
+echo ERROR: JAVA_HOME is set to an invalid directory: %JAVA_HOME%
+echo.
+echo Please set the JAVA_HOME variable in your environment to match the
+echo location of your Java installation.
+
+goto fail
+
+:execute
+@rem Setup the command line
+
+set CLASSPATH=%APP_HOME%\gradle\wrapper\gradle-wrapper.jar
+
+
+@rem Execute Gradle
+"%JAVA_EXE%" %DEFAULT_JVM_OPTS% %JAVA_OPTS% %GRADLE_OPTS% "-Dorg.gradle.appname=%APP_BASE_NAME%" -classpath "%CLASSPATH%" org.gradle.wrapper.GradleWrapperMain %*
+
+:end
+@rem End local scope for the variables with windows NT shell
+if "%ERRORLEVEL%"=="0" goto mainEnd
+
+:fail
+rem Set variable GRADLE_EXIT_CONSOLE if you need the _script_ return code instead of
+rem the _cmd.exe /c_ return code!
+if  not "" == "%GRADLE_EXIT_CONSOLE%" exit 1
+exit /b 1
+
+:mainEnd
+if "%OS%"=="Windows_NT" endlocal
+
+:omega

settings.gradle.kts

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+rootProject.name = "concrete"

src/main/kotlin/lgbt/mystic/foundation/concrete/ConcreteExtension.kt

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+package lgbt.mystic.foundation.concrete
+
+import org.gradle.api.provider.Property
+
+interface ConcreteExtension {
+  val paperVersionGroup: Property<String>
+  val minecraftServerPath: Property<String>
+}

src/main/kotlin/lgbt/mystic/foundation/concrete/ConcreteGradlePlugin.kt

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+package lgbt.mystic.foundation.concrete
+
+import org.gradle.api.Plugin
+import org.gradle.api.Project
+import org.gradle.kotlin.dsl.create
+
+class ConcreteGradlePlugin : Plugin<Project> {
+  override fun apply(project: Project) {
+    project.extensions.create<ConcreteExtension>("concrete")
+    val setupPaperServer = project.tasks.create<SetupPaperServer>("setupPaperServer")
+    project.afterEvaluate { ->
+      setupPaperServer.dependsOn(*project.subprojects
+        // TODO: Foundation specific
+        .filter { it.isFoundationPlugin() }
+        .map { it.tasks.getByName("shadowJar") }
+        .toTypedArray()
+      )
+    }
+    val runPaperServer = project.tasks.create<RunPaperServer>("runPaperServer")
+    runPaperServer.dependsOn(setupPaperServer)
+
+    val updateManifests = project.tasks.create<UpdateManifestTask>("updateManifests")
+    project.tasks.getByName("assemble").dependsOn(updateManifests)
+  }
+}

src/main/kotlin/lgbt/mystic/foundation/concrete/ConcreteProjectPlugin.kt

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+package lgbt.mystic.foundation.concrete
+
+import org.gradle.api.Plugin
+import org.gradle.api.Project
+
+class ConcreteProjectPlugin : Plugin<Project> {
+  override fun apply(project: Project) {
+    val versionWithBuild = if (System.getenv("CI_PIPELINE_IID") != null) {
+      project.rootProject.version.toString() + ".${System.getenv("CI_PIPELINE_IID")}"
+    } else {
+      "DEV"
+    }
+
+    project.version = versionWithBuild
+  }
+}

src/main/kotlin/lgbt/mystic/foundation/concrete/Globals.kt

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+package lgbt.mystic.foundation.concrete
+
+import com.google.gson.Gson
+
+object Globals {
+  val gson = Gson()
+}

src/main/kotlin/lgbt/mystic/foundation/concrete/PaperVersionClient.kt

@@ -0,0 +1,46 @@
+package lgbt.mystic.foundation.concrete
+
+import com.google.gson.Gson
+import java.net.URI
+import java.net.http.HttpClient
+import java.net.http.HttpRequest
+import java.net.http.HttpResponse
+
+class PaperVersionClient(
+  val client: HttpClient = HttpClient.newHttpClient(),
+  private val gson: Gson = Globals.gson
+) {
+  private val apiBaseUrl = URI.create("https://papermc.io/api/v2/")
+
+  fun getVersionBuilds(group: String): List<PaperBuild> {
+    val response = client.send(
+      HttpRequest.newBuilder()
+        .GET()
+        .uri(apiBaseUrl.resolve("projects/paper/version_group/${group}/builds"))
+        .build(),
+      HttpResponse.BodyHandlers.ofString()
+    )
+
+    val body = response.body()
+    val root = gson.fromJson(body, PaperVersionRoot::class.java)
+    return root.builds
+  }
+
+  fun resolveDownloadUrl(build: PaperBuild, download: PaperVersionDownload): URI =
+    apiBaseUrl.resolve("projects/paper/versions/${build.version}/builds/${build.build}/downloads/${download.name}")
+
+  data class PaperVersionRoot(
+    val builds: List<PaperBuild>
+  )
+
+  data class PaperBuild(
+    val version: String,
+    val build: Int,
+    val downloads: Map<String, PaperVersionDownload>
+  )
+
+  data class PaperVersionDownload(
+    val name: String,
+    val sha256: String
+  )
+}

src/main/kotlin/lgbt/mystic/foundation/concrete/RunPaperServer.kt

@@ -0,0 +1,33 @@
+package lgbt.mystic.foundation.concrete
+
+import org.gradle.api.DefaultTask
+import org.gradle.api.tasks.TaskAction
+import org.gradle.kotlin.dsl.getByType
+import java.io.File
+import java.util.jar.JarFile
+
+open class RunPaperServer : DefaultTask() {
+  init {
+    outputs.upToDateWhen { false }
+  }
+
+  @TaskAction
+  fun runPaperServer() {
+    val concrete = project.extensions.getByType<ConcreteExtension>()
+
+    val minecraftServerDirectory = project.file(concrete.minecraftServerPath.get())
+    val paperJarFile = minecraftServerDirectory.resolve("paper.jar")
+    val mainClassName = readMainClass(paperJarFile)
+
+    project.javaexec {
+      classpath(paperJarFile.absolutePath)
+      workingDir(minecraftServerDirectory)
+      args("nogui")
+      mainClass.set(mainClassName)
+    }
+  }
+
+  private fun readMainClass(file: File): String = JarFile(file).use { jar ->
+    jar.manifest.mainAttributes.getValue("Main-Class")!!
+  }
+}

src/main/kotlin/lgbt/mystic/foundation/concrete/SetupPaperServer.kt

@@ -0,0 +1,69 @@
+package lgbt.mystic.foundation.concrete
+
+import org.gradle.api.DefaultTask
+import org.gradle.api.tasks.Input
+import org.gradle.api.tasks.TaskAction
+import org.gradle.api.tasks.options.Option
+import org.gradle.kotlin.dsl.getByType
+import java.io.File
+import java.nio.file.Files
+
+open class SetupPaperServer : DefaultTask() {
+  init {
+    outputs.upToDateWhen { false }
+  }
+
+  @get:Input
+  @set:Option(option = "update", description = "Update Paper Server")
+  var shouldUpdatePaperServer = false
+
+  private val paperVersionClient = PaperVersionClient()
+
+  @TaskAction
+  fun downloadPaperTask() {
+    val concrete = project.extensions.getByType<ConcreteExtension>()
+    val minecraftServerDirectory = project.file(concrete.minecraftServerPath.get())
+
+    if (!minecraftServerDirectory.exists()) {
+      minecraftServerDirectory.mkdirs()
+    }
+
+    val paperJarFile = project.file("${concrete.minecraftServerPath.get()}/paper.jar")
+    if (!paperJarFile.exists() || shouldUpdatePaperServer) {
+      downloadLatestBuild(concrete.paperVersionGroup.get(), paperJarFile)
+    }
+
+    val paperPluginsDirectory = minecraftServerDirectory.resolve("plugins")
+
+    if (!paperPluginsDirectory.exists()) {
+      paperPluginsDirectory.mkdirs()
+    }
+
+    for (project in project.subprojects) {
+      if (!project.isFoundationPlugin()) {
+        continue
+      }
+
+      val pluginJarFile = project.buildDir.resolve("libs/${project.name}-DEV-plugin.jar")
+      val pluginLinkFile = paperPluginsDirectory.resolve("${project.name}.jar")
+      if (pluginLinkFile.exists()) {
+        pluginLinkFile.delete()
+      }
+
+      Files.createSymbolicLink(pluginLinkFile.toPath(), pluginJarFile.toPath())
+    }
+  }
+
+  private fun downloadLatestBuild(paperVersionGroup: String, paperJarFile: File) {
+    val builds = paperVersionClient.getVersionBuilds(paperVersionGroup)
+    val build = builds.last()
+    val download = build.downloads["application"]!!
+    val url = paperVersionClient.resolveDownloadUrl(build, download)
+    val downloader = SmartDownloader(paperJarFile.toPath(), url, download.sha256)
+    if (downloader.download()) {
+      logger.lifecycle("Installed Paper Server ${build.version} build ${build.build}")
+    } else {
+      logger.lifecycle("Paper Server ${build.version} build ${build.build} is up-to-date")
+    }
+  }
+}

src/main/kotlin/lgbt/mystic/foundation/concrete/SmartDownloader.kt

@@ -0,0 +1,78 @@
+package lgbt.mystic.foundation.concrete
+
+import java.net.URI
+import java.nio.file.Files
+import java.nio.file.Path
+import java.security.MessageDigest
+
+class SmartDownloader(
+  private val localFilePath: Path,
+  private val remoteDownloadUrl: URI,
+  private val sha256: String
+) {
+  fun download(): Boolean {
+    val hashResult = checkLocalFileHash()
+    if (hashResult != HashResult.ValidHash) {
+      downloadRemoteFile()
+      return false
+    }
+    return true
+  }
+
+  private fun downloadRemoteFile() {
+    val url = remoteDownloadUrl.toURL()
+    val remoteFileStream = url.openStream()
+    val localFileStream = Files.newOutputStream(localFilePath)
+    remoteFileStream.transferTo(localFileStream)
+    val hashResult = checkLocalFileHash()
+    if (hashResult != HashResult.ValidHash) {
+      throw RuntimeException("Download of $remoteDownloadUrl did not result in valid hash.")
+    }
+  }
+
+  private fun checkLocalFileHash(): HashResult {
+    if (!Files.exists(localFilePath)) {
+      return HashResult.DoesNotExist
+    }
+
+    val digest = MessageDigest.getInstance("SHA-256")
+    val localFileStream = Files.newInputStream(localFilePath)
+    val buffer = ByteArray(16 * 1024)
+
+    while (true) {
+      val size = localFileStream.read(buffer)
+      if (size <= 0) {
+        break
+      }
+
+      val bytes = buffer.take(size).toByteArray()
+      digest.update(bytes)
+    }
+
+    val sha256Bytes = digest.digest()
+    val localSha256Hash = bytesToHex(sha256Bytes)
+    return if (localSha256Hash.equals(sha256, ignoreCase = true)) {
+      HashResult.ValidHash
+    } else {
+      HashResult.InvalidHash
+    }
+  }
+
+  private fun bytesToHex(hash: ByteArray): String {
+    val hexString = StringBuilder(2 * hash.size)
+    for (i in hash.indices) {
+      val hex = Integer.toHexString(0xff and hash[i].toInt())
+      if (hex.length == 1) {
+        hexString.append('0')
+      }
+      hexString.append(hex)
+    }
+    return hexString.toString()
+  }
+
+  enum class HashResult {
+    DoesNotExist,
+    InvalidHash,
+    ValidHash
+  }
+}

src/main/kotlin/lgbt/mystic/foundation/concrete/UpdateManifestTask.kt

@@ -0,0 +1,32 @@
+package lgbt.mystic.foundation.concrete
+
+import org.gradle.api.DefaultTask
+import org.gradle.api.tasks.TaskAction
+import java.nio.file.Files
+import java.nio.file.Path
+
+open class UpdateManifestTask : DefaultTask() {
+  @TaskAction
+  fun update() {
+    val manifestsDir = ensureManifestsDir()
+    val updateFile = manifestsDir.resolve("update.json")
+    val rootPath = project.rootProject.rootDir.toPath()
+    val updateManifest = project.findPluginProjects().mapNotNull { project ->
+      val paths = project.shadowJarOutputs.allFilesRelativeToPath(rootPath)
+      if (paths.isNotEmpty()) {
+        project.name to mapOf(
+          "version" to project.version,
+          "artifacts" to paths.map { it.toUnixString() }
+        )
+      } else null
+    }.toMap()
+
+    Files.writeString(updateFile, Globals.gson.toJson(updateManifest))
+  }
+
+  private fun ensureManifestsDir(): Path {
+    val manifestsDir = project.buildDir.resolve("manifests")
+    manifestsDir.mkdirs()
+    return manifestsDir.toPath()
+  }
+}

src/main/kotlin/lgbt/mystic/foundation/concrete/extensions.kt

@@ -0,0 +1,17 @@
+package lgbt.mystic.foundation.concrete
+
+import org.gradle.api.Project
+import org.gradle.api.tasks.TaskOutputs
+import java.nio.file.FileSystems
+import java.nio.file.Path
+
+fun Project.isFoundationPlugin() = name.startsWith("foundation-")
+
+fun Project.findPluginProjects() = rootProject.subprojects.filter { project -> project.isFoundationPlugin() }
+
+val Project.shadowJarOutputs: TaskOutputs
+  get() = project.tasks.getByName("shadowJar").outputs
+
+fun TaskOutputs.allFilesRelativeToPath(root: Path): List<Path> = files.map { root.relativize(it.toPath()) }
+
+fun Path.toUnixString() = toString().replace(FileSystems.getDefault().separator, "/")