Updated version of assemble_maven rewritten in Kotlin (typedb#293)

## What is the goal of this PR?

Rewrite `assemble_maven` in Kotlin in order for us to understand it better and improve its maintability/readability.

## What are the changes implemented in this PR?

Implement `assemble_maven` in `@graknlabs_bazel_distribution//maven:new_rules.bzl`

WORKSPACE

@@ -22,8 +22,28 @@ workspace(name="graknlabs_bazel_distribution")
 load("@bazel_tools//tools/build_defs/repo:git.bzl", "git_repository")
 
 # Load @rules_python
-load("//common:deps.bzl", "rules_python")
+load("//common:deps.bzl", "rules_python", "rules_kotlin", "rules_jvm_external")
 rules_python()
+rules_kotlin()
+rules_jvm_external()
+
+# Load @io_bazel_rules_kotlin
+load("@io_bazel_rules_kotlin//kotlin:kotlin.bzl", "kotlin_repositories", "kt_register_toolchains")
+kotlin_repositories()
+kt_register_toolchains()
+
+load("@graknlabs_bazel_distribution//maven:deps.bzl", "maven_artifacts_with_versions")
+load("@rules_jvm_external//:defs.bzl", "maven_install")
+maven_install(
+    artifacts = maven_artifacts_with_versions,
+    repositories = [
+        "https://repo1.maven.org/maven2",
+    ],
+    strict_visibility = True,
+    version_conflict_policy = "pinned",
+    fetch_sources = True,
+)
+
 
 # Load @graknlabs_bazel_distribution_pip
 load("//pip:deps.bzl", pip_deps = "deps")
@@ -43,3 +63,4 @@ git_repository(
 )
 load("@io_bazel_stardoc//:setup.bzl", "stardoc_repositories")
 stardoc_repositories()
+

common/deps.bzl

@@ -28,3 +28,22 @@ def rules_pkg():
         ],
         patch_args = ["-p1"],
     )
+
+
+def rules_kotlin():
+    http_archive(
+        name = "io_bazel_rules_kotlin",
+        urls = ["https://github.com/bazelbuild/rules_kotlin/archive/legacy-1.3.0.zip"],
+        type = "zip",
+        strip_prefix = "rules_kotlin-legacy-1.3.0",
+        sha256 = "4fd769fb0db5d3c6240df8a9500515775101964eebdf85a3f9f0511130885fde",
+    )
+
+
+def rules_jvm_external():
+    http_archive(
+        name = "rules_jvm_external",
+        strip_prefix = "rules_jvm_external-3.2",
+        sha256 = "82262ff4223c5fda6fb7ff8bd63db8131b51b413d26eb49e3131037e79e324af",
+        url = "https://github.com/bazelbuild/rules_jvm_external/archive/3.2.zip",
+    )

maven/BUILD

@@ -45,15 +45,56 @@ py_binary(
 # FIXME(vmax): I couldn't make it a kt_jvm_binary because
 #  it complained it couldn't find `java` executable
 kt_jvm_library(
-    name = "repackager_lib",
+    name = "repackager-lib",
     srcs = ["Repackager.kt"],
 )
 
+
+kt_jvm_library(
+    name = "pom-generator-lib",
+    deps = [
+      "@maven//:com_eclipsesource_minimal_json_minimal_json",
+      "@maven//:info_picocli_picocli",
+    ],
+    srcs = [
+        "PomGenerator.kt",
+    ]
+)
+
+java_binary(
+    name = "pom-generator",
+    runtime_deps = [
+        ":pom-generator-lib"
+    ],
+    main_class = "PomGeneratorKt",
+    visibility = ["//visibility:public"]
+)
+
 java_binary(
     name = "repackager",
     runtime_deps = [
-        ":repackager_lib"
+        ":repackager-lib"
     ],
     main_class = "RepackagerKt",
     visibility = ["//visibility:public"]
 )
+
+
+kt_jvm_library(
+    name = "jar-assembler-lib",
+    deps = [
+      "@maven//:info_picocli_picocli",
+    ],
+    srcs = [
+        "JarAssembler.kt"
+    ]
+)
+
+java_binary(
+    name = "jar-assembler",
+    runtime_deps = [
+        ":jar-assembler-lib"
+    ],
+    main_class = "JarAssemblerKt",
+    visibility = ["//visibility:public"]
+)

maven/JarAssembler.kt

@@ -0,0 +1,68 @@
+import picocli.CommandLine
+import picocli.CommandLine.Command
+import picocli.CommandLine.Option
+import java.io.BufferedInputStream
+import java.io.BufferedOutputStream
+import java.io.File
+import java.io.FileOutputStream
+import java.util.*
+import java.util.concurrent.Callable
+import java.util.zip.ZipEntry
+import java.util.zip.ZipFile
+import java.util.zip.ZipOutputStream
+import kotlin.system.exitProcess
+
+
+@Command(name = "jar-assembler", mixinStandardHelpOptions = true)
+class JarAssembler : Callable<Unit> {
+
+    @Option(names = ["--output"], required = true)
+    lateinit var output_file: File
+
+    @Option(names = ["--prefix"])
+    lateinit var prefix: String
+
+    @Option(names = ["--group-id"])
+    var groupId = ""
+
+    @Option(names = ["--artifact-id"])
+    var artifactId = ""
+
+    @Option(names = ["--pom-file"])
+    var pomFile: File? = null
+
+    @Option(names = ["--jars"], split = ";")
+    lateinit var jars: Array<File>
+
+    val entryNames = mutableSetOf<String>()
+
+    override fun call() {
+        ZipOutputStream(BufferedOutputStream(FileOutputStream(output_file))).use { out ->
+            if (pomFile != null) {
+                val pomFileEntry = ZipEntry("META-INF/maven/${groupId}/${artifactId}/pom.xml")
+                out.putNextEntry(pomFileEntry)
+                out.write(pomFile!!.readBytes())
+            }
+            for (jar in jars) {
+                ZipFile(jar).use { jarZip ->
+                    jarZip.entries().asSequence().forEach { entry ->
+                        if (entry.name.contains("META-INF")) {
+                            return@forEach
+                        }
+                        if (entryNames.contains(entry.name)) {
+                            return@forEach
+                        }
+                        entryNames.add(entry.name)
+                        BufferedInputStream(jarZip.getInputStream(entry)).use { inputStream ->
+                            val newEntry = ZipEntry(prefix + entry.name)
+                            out.putNextEntry(newEntry)
+                            inputStream.copyTo(out, 1024)
+                        }
+                    }
+                }
+            }
+        }
+    }
+}
+
+fun main(args: Array<String>): Unit = exitProcess(CommandLine(JarAssembler()).execute(*args))