Test CI

.editorconfig

@@ -1,16 +0,0 @@
-root = true
-
-[*]
-charset = utf-8
-end_of_line = lf
-indent_size = 4
-indent_style = space
-insert_final_newline = false
-max_line_length = 120
-tab_width = 4
-
-[{*.yaml,*.yml}]
-indent_size = 2
-
-[{*.kt,*.kts}]
-ij_kotlin_packages_to_use_import_on_demand = org.junit.jupiter.api,aws.sdk.kotlin.services.s3,kotlinx.coroutines,java.io,ziputils

.github/workflows/publish.yaml

@@ -1,8 +1,11 @@
 name: Publish Workflow
 on:
+  pull_request:
+    branches:
+      - main
   push:
-    tags:
+    branches:
-      - v*
+      - main
 jobs:
   publish:
     name: Publish library
@@ -38,7 +41,7 @@ jobs:
         run: ./gradlew shadowJar
 
       - name: Upload artifacts
-        uses: actions/upload-artifact@v3
+        uses: actions/upload-artifact@v4
         with:
           name: ShadowJAR
           path: build/libs/*-all.jar

.idea/uiDesigner.xml

@@ -1,124 +0,0 @@
-<?xml version="1.0" encoding="UTF-8"?>
-<project version="4">
-  <component name="Palette2">
-    <group name="Swing">
-      <item class="com.intellij.uiDesigner.HSpacer" tooltip-text="Horizontal Spacer" icon="/com/intellij/uiDesigner/icons/hspacer.svg" removable="false" auto-create-binding="false" can-attach-label="false">
-        <default-constraints vsize-policy="1" hsize-policy="6" anchor="0" fill="1" />
-      </item>
-      <item class="com.intellij.uiDesigner.VSpacer" tooltip-text="Vertical Spacer" icon="/com/intellij/uiDesigner/icons/vspacer.svg" removable="false" auto-create-binding="false" can-attach-label="false">
-        <default-constraints vsize-policy="6" hsize-policy="1" anchor="0" fill="2" />
-      </item>
-      <item class="javax.swing.JPanel" icon="/com/intellij/uiDesigner/icons/panel.svg" removable="false" auto-create-binding="false" can-attach-label="false">
-        <default-constraints vsize-policy="3" hsize-policy="3" anchor="0" fill="3" />
-      </item>
-      <item class="javax.swing.JScrollPane" icon="/com/intellij/uiDesigner/icons/scrollPane.svg" removable="false" auto-create-binding="false" can-attach-label="true">
-        <default-constraints vsize-policy="7" hsize-policy="7" anchor="0" fill="3" />
-      </item>
-      <item class="javax.swing.JButton" icon="/com/intellij/uiDesigner/icons/button.svg" removable="false" auto-create-binding="true" can-attach-label="false">
-        <default-constraints vsize-policy="0" hsize-policy="3" anchor="0" fill="1" />
-        <initial-values>
-          <property name="text" value="Button" />
-        </initial-values>
-      </item>
-      <item class="javax.swing.JRadioButton" icon="/com/intellij/uiDesigner/icons/radioButton.svg" removable="false" auto-create-binding="true" can-attach-label="false">
-        <default-constraints vsize-policy="0" hsize-policy="3" anchor="8" fill="0" />
-        <initial-values>
-          <property name="text" value="RadioButton" />
-        </initial-values>
-      </item>
-      <item class="javax.swing.JCheckBox" icon="/com/intellij/uiDesigner/icons/checkBox.svg" removable="false" auto-create-binding="true" can-attach-label="false">
-        <default-constraints vsize-policy="0" hsize-policy="3" anchor="8" fill="0" />
-        <initial-values>
-          <property name="text" value="CheckBox" />
-        </initial-values>
-      </item>
-      <item class="javax.swing.JLabel" icon="/com/intellij/uiDesigner/icons/label.svg" removable="false" auto-create-binding="false" can-attach-label="false">
-        <default-constraints vsize-policy="0" hsize-policy="0" anchor="8" fill="0" />
-        <initial-values>
-          <property name="text" value="Label" />
-        </initial-values>
-      </item>
-      <item class="javax.swing.JTextField" icon="/com/intellij/uiDesigner/icons/textField.svg" removable="false" auto-create-binding="true" can-attach-label="true">
-        <default-constraints vsize-policy="0" hsize-policy="6" anchor="8" fill="1">
-          <preferred-size width="150" height="-1" />
-        </default-constraints>
-      </item>
-      <item class="javax.swing.JPasswordField" icon="/com/intellij/uiDesigner/icons/passwordField.svg" removable="false" auto-create-binding="true" can-attach-label="true">
-        <default-constraints vsize-policy="0" hsize-policy="6" anchor="8" fill="1">
-          <preferred-size width="150" height="-1" />
-        </default-constraints>
-      </item>
-      <item class="javax.swing.JFormattedTextField" icon="/com/intellij/uiDesigner/icons/formattedTextField.svg" removable="false" auto-create-binding="true" can-attach-label="true">
-        <default-constraints vsize-policy="0" hsize-policy="6" anchor="8" fill="1">
-          <preferred-size width="150" height="-1" />
-        </default-constraints>
-      </item>
-      <item class="javax.swing.JTextArea" icon="/com/intellij/uiDesigner/icons/textArea.svg" removable="false" auto-create-binding="true" can-attach-label="true">
-        <default-constraints vsize-policy="6" hsize-policy="6" anchor="0" fill="3">
-          <preferred-size width="150" height="50" />
-        </default-constraints>
-      </item>
-      <item class="javax.swing.JTextPane" icon="/com/intellij/uiDesigner/icons/textPane.svg" removable="false" auto-create-binding="true" can-attach-label="true">
-        <default-constraints vsize-policy="6" hsize-policy="6" anchor="0" fill="3">
-          <preferred-size width="150" height="50" />
-        </default-constraints>
-      </item>
-      <item class="javax.swing.JEditorPane" icon="/com/intellij/uiDesigner/icons/editorPane.svg" removable="false" auto-create-binding="true" can-attach-label="true">
-        <default-constraints vsize-policy="6" hsize-policy="6" anchor="0" fill="3">
-          <preferred-size width="150" height="50" />
-        </default-constraints>
-      </item>
-      <item class="javax.swing.JComboBox" icon="/com/intellij/uiDesigner/icons/comboBox.svg" removable="false" auto-create-binding="true" can-attach-label="true">
-        <default-constraints vsize-policy="0" hsize-policy="2" anchor="8" fill="1" />
-      </item>
-      <item class="javax.swing.JTable" icon="/com/intellij/uiDesigner/icons/table.svg" removable="false" auto-create-binding="true" can-attach-label="false">
-        <default-constraints vsize-policy="6" hsize-policy="6" anchor="0" fill="3">
-          <preferred-size width="150" height="50" />
-        </default-constraints>
-      </item>
-      <item class="javax.swing.JList" icon="/com/intellij/uiDesigner/icons/list.svg" removable="false" auto-create-binding="true" can-attach-label="false">
-        <default-constraints vsize-policy="6" hsize-policy="2" anchor="0" fill="3">
-          <preferred-size width="150" height="50" />
-        </default-constraints>
-      </item>
-      <item class="javax.swing.JTree" icon="/com/intellij/uiDesigner/icons/tree.svg" removable="false" auto-create-binding="true" can-attach-label="false">
-        <default-constraints vsize-policy="6" hsize-policy="6" anchor="0" fill="3">
-          <preferred-size width="150" height="50" />
-        </default-constraints>
-      </item>
-      <item class="javax.swing.JTabbedPane" icon="/com/intellij/uiDesigner/icons/tabbedPane.svg" removable="false" auto-create-binding="true" can-attach-label="false">
-        <default-constraints vsize-policy="3" hsize-policy="3" anchor="0" fill="3">
-          <preferred-size width="200" height="200" />
-        </default-constraints>
-      </item>
-      <item class="javax.swing.JSplitPane" icon="/com/intellij/uiDesigner/icons/splitPane.svg" removable="false" auto-create-binding="false" can-attach-label="false">
-        <default-constraints vsize-policy="3" hsize-policy="3" anchor="0" fill="3">
-          <preferred-size width="200" height="200" />
-        </default-constraints>
-      </item>
-      <item class="javax.swing.JSpinner" icon="/com/intellij/uiDesigner/icons/spinner.svg" removable="false" auto-create-binding="true" can-attach-label="true">
-        <default-constraints vsize-policy="0" hsize-policy="6" anchor="8" fill="1" />
-      </item>
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-        <default-constraints vsize-policy="0" hsize-policy="6" anchor="8" fill="1" />
-      </item>
-      <item class="javax.swing.JSeparator" icon="/com/intellij/uiDesigner/icons/separator.svg" removable="false" auto-create-binding="false" can-attach-label="false">
-        <default-constraints vsize-policy="6" hsize-policy="6" anchor="0" fill="3" />
-      </item>
-      <item class="javax.swing.JProgressBar" icon="/com/intellij/uiDesigner/icons/progressbar.svg" removable="false" auto-create-binding="true" can-attach-label="false">
-        <default-constraints vsize-policy="0" hsize-policy="6" anchor="0" fill="1" />
-      </item>
-      <item class="javax.swing.JToolBar" icon="/com/intellij/uiDesigner/icons/toolbar.svg" removable="false" auto-create-binding="false" can-attach-label="false">
-        <default-constraints vsize-policy="0" hsize-policy="6" anchor="0" fill="1">
-          <preferred-size width="-1" height="20" />
-        </default-constraints>
-      </item>
-      <item class="javax.swing.JToolBar$Separator" icon="/com/intellij/uiDesigner/icons/toolbarSeparator.svg" removable="false" auto-create-binding="false" can-attach-label="false">
-        <default-constraints vsize-policy="0" hsize-policy="0" anchor="0" fill="1" />
-      </item>
-      <item class="javax.swing.JScrollBar" icon="/com/intellij/uiDesigner/icons/scrollbar.svg" removable="false" auto-create-binding="true" can-attach-label="false">
-        <default-constraints vsize-policy="6" hsize-policy="0" anchor="0" fill="2" />
-      </item>
-    </group>
-  </component>
-</project>

README.md

@@ -6,64 +6,6 @@ an AWS S3 bucket.
 This tool is released as a JAR in the [release page](https://git.koval.net/cyclane/teamcity-executors-test-task/releases).
 Use `java -jar <backup-jar-name>.jar --help` for more detailed usage instructions.
 
-### --help
-```
-Usage: s3backup-tool [<options>] <command> [<args>]...
-
-  A simple AWS S3 backup tool. This tool assumes credentials are properly configured using aws-cli.
-
-Options:
-  -h, --help  Show this message and exit
-
-Commands:
-  create        Create a backup of a file or directory.
-  restore       Restore a backup from AWS S3.
-  restore-file  Restore a single file from a backup from AWS S3.
-```
-
-#### Subcommands
-```
-Usage: s3backup-tool create [<options>] <source> <bucket>
-
-  Create a backup of a file or directory.
-
-Options:
-  -h, --help  Show this message and exit
-
-Arguments:
-  <source>  File or directory to backup
-  <bucket>  Name of S3 bucket to backup to
-```
-
-```
-Usage: s3backup-tool restore [<options>] <bucket> <backupkey> <destination>
-
-  Restore a backup from AWS S3.
-
-Options:
-  -h, --help  Show this message and exit
-
-Arguments:
-  <bucket>       Name of S3 bucket to restore the backup from
-  <backupkey>    The S3 key of the backup to restore
-  <destination>  Directory to restore to
-```
-
-```
-Usage: s3backup-tool restore-file [<options>] <bucket> <backupkey> <filepath> <destination>
-
-  Restore a single file from a backup from AWS S3.
-
-Options:
-  -h, --help  Show this message and exit
-
-Arguments:
-  <bucket>       Name of S3 bucket to restore the backup from
-  <backupkey>    The S3 key of the backup to restore
-  <filepath>     File path within the backup
-  <destination>  Directory to restore to
-```
-
 ## Assumptions
 1. This test task is not interested in re-implementations of common libraries (AWS SDK, Clikt, Gradle Shadow, ...)
 2. The last part (restoration of a single file) should be optimised so that only the part of the blob required for this 

build.gradle.kts

@@ -1,7 +1,7 @@
+import com.github.jengelman.gradle.plugins.shadow.tasks.ShadowJar
+
 plugins {
-    application
     kotlin("jvm") version "1.9.21"
-    id("org.jlleitschuh.gradle.ktlint") version "12.0.3"
     id("com.github.johnrengelman.shadow") version "8.1.1"
 }
 
@@ -16,7 +16,6 @@ dependencies {
     implementation("aws.sdk.kotlin:s3:1.0.25")
     implementation("org.slf4j:slf4j-simple:2.0.9")
     implementation("org.jetbrains.kotlinx:kotlinx-coroutines-core:1.7.3")
-    implementation("com.github.ajalt.clikt:clikt:4.2.1")
     testImplementation("org.jetbrains.kotlin:kotlin-test")
 }
 
@@ -26,6 +25,8 @@ tasks.test {
 kotlin {
     jvmToolchain(17)
 }
-application {
+tasks.jar {
-    mainClass.set("MainKt")
+    manifest {
+        attributes("Main-Class" to "backup.MainKt")
+    }
 }

settings.gradle.kts

@@ -2,3 +2,4 @@ plugins {
     id("org.gradle.toolchains.foojay-resolver-convention") version "0.5.0"
 }
 rootProject.name = "teamcity-executors-test-task"
+

src/main/kotlin/Main.kt

@@ -1,80 +0,0 @@
-import aws.sdk.kotlin.services.s3.S3Client
-import backup.BackupClient
-import com.github.ajalt.clikt.core.CliktCommand
-import com.github.ajalt.clikt.core.subcommands
-import com.github.ajalt.clikt.parameters.arguments.argument
-import com.github.ajalt.clikt.parameters.arguments.help
-import com.github.ajalt.clikt.parameters.types.file
-import kotlinx.coroutines.runBlocking
-import kotlin.system.exitProcess
-
-fun main(args: Array<String>) =
-    runBlocking {
-        S3Client.fromEnvironment().use { s3 ->
-            S3BackupTool()
-                .subcommands(
-                    Create(s3),
-                    Restore(s3),
-                    RestoreFile(s3),
-                )
-                .main(args)
-        }
-    }
-
-class S3BackupTool : CliktCommand(
-    help = "A simple AWS S3 backup tool. This tool assumes credentials are properly configured using aws-cli.",
-) {
-    override fun run() {
-        shortHelp(currentContext)
-    }
-}
-
-class Create(val s3: S3Client) : CliktCommand(
-    help = "Create a backup of a file or directory.",
-) {
-    val source by argument().file(mustExist = true).help("File or directory to backup")
-    val bucket by argument().help("Name of S3 bucket to backup to")
-
-    override fun run() =
-        runBlocking {
-            val backupKey = BackupClient(s3, bucket).upload(source)
-            echo("Successfully created backup with key '$backupKey'")
-        }
-}
-
-class Restore(val s3: S3Client) : CliktCommand(
-    help = "Restore a backup from AWS S3.",
-) {
-    val bucket by argument().help("Name of S3 bucket to restore the backup from")
-    val backupKey by argument().help("The S3 key of the backup to restore")
-    val destination by argument().file(mustExist = true).help("Directory to restore to")
-
-    override fun run() =
-        runBlocking {
-            if (!destination.isDirectory) {
-                echo("Destination must be an existing directory", err = true)
-                exitProcess(1)
-            }
-            BackupClient(s3, bucket).restore(destination.toPath(), backupKey)
-            echo("Successfully restored backup '$backupKey' to '$destination'")
-        }
-}
-
-class RestoreFile(val s3: S3Client) : CliktCommand(
-    help = "Restore a single file from a backup from AWS S3.",
-) {
-    val bucket by argument().help("Name of S3 bucket to restore the backup from")
-    val backupKey by argument().help("The S3 key of the backup to restore")
-    val filePath by argument().help("File path within the backup")
-    val destination by argument().file(mustExist = true).help("Directory to restore to")
-
-    override fun run() =
-        runBlocking {
-            if (!destination.isDirectory) {
-                echo("Destination must be an existing directory", err = true)
-                exitProcess(1)
-            }
-            BackupClient(s3, bucket).restoreFile(destination.toPath(), backupKey, filePath)
-            echo("Successfully restored '$filePath' from backup '$backupKey' to '$destination'")
-        }
-}

src/main/kotlin/backup/BackupClient.kt

@@ -24,25 +24,16 @@ import java.util.zip.ZipInputStream
 import java.util.zip.ZipOutputStream
 import kotlin.io.path.createDirectory
 
-/**
- * AWS S3 backup client.
- */
 class BackupClient(
     private val s3: S3Client,
     private val bucketName: String,
-    private val bufSize: Int = 1024 * 1024 * 32,
+    private val bufSize: Int = 1024 * 1024 * 100
 ) {
-    /**
+    suspend fun upload(file: File) = coroutineScope {
-     * Upload a file/directory backup to AWS S3.
+        val backupKey = "${file.name}/${Instant.now()}.zip"
-     * @param file The File object for the file or directory.
-     */
-    suspend fun upload(file: File) =
-        coroutineScope {
-            val backupKey = "${file.canonicalFile.name}/${Instant.now()}.zip"
         PipedInputStream().use { inputStream ->
             val outputStream = PipedOutputStream(inputStream)
-                val zipper =
+            val zipper = launch(Dispatchers.IO) {
-                    launch(Dispatchers.IO) {
                 file.compressToZip(outputStream)
             }
 
@@ -52,8 +43,7 @@ class BackupClient(
                 // Large upload, use multipart
                 // TODO: multipart uploads can be asynchronous, which would improve
                 //       performance a little bit for big uploads.
-                    val upload =
+                val upload = s3.createMultipartUpload {
-                        s3.createMultipartUpload {
                     bucket = bucketName
                     key = backupKey
                 }
@@ -62,14 +52,13 @@ class BackupClient(
                     var number = 1
                     var bytesRead = initialRead
                     while (bytesRead > 0) {
-                            val part =
+                        val part = s3.uploadPart {
-                                s3.uploadPart {
                             bucket = bucketName
                             key = backupKey
                             partNumber = number
                             uploadId = upload.uploadId
                             body = ByteStream.fromBytes(data.take(bytesRead))
-                                }.toCompletedPart(number)
+                        }.asCompletedPart(number)
                         uploadParts.add(part)
                         number++
                         bytesRead = inputStream.readNBytes(data, 0, bufSize)
@@ -78,8 +67,7 @@ class BackupClient(
                         bucket = bucketName
                         key = backupKey
                         uploadId = upload.uploadId
-                            multipartUpload =
+                        multipartUpload = CompletedMultipartUpload {
-                                CompletedMultipartUpload {
                             parts = uploadParts
                         }
                     }
@@ -104,44 +92,24 @@ class BackupClient(
         backupKey
     }
 
-    /**
+    suspend fun restore(destination: Path, backupKey: String) = coroutineScope {
-     * Restore a backup from AWS S3.
+        val req = GetObjectRequest {
-     * @param destination The destination directory path for the backup contents.
-     * @param backupKey The S3 key of the backup.
-     */
-    suspend fun restore(
-        destination: Path,
-        backupKey: String,
-    ) = coroutineScope {
-        val req =
-            GetObjectRequest {
             bucket = bucketName
             key = backupKey
         }
         s3.getObject(req) { resp ->
             ZipInputStream(
                 resp.body?.toInputStream()
-                    ?: throw IOException("S3 response is missing body"),
+                    ?: throw IOException("S3 response is missing body")
             ).use { zipStream ->
                 zipStream.decompress { destination.resolve(it) }
             }
         }
     }
 
-    /**
+    suspend fun restoreFile(destination: Path, backupKey: String, fileName: String) = coroutineScope {
-     * Restore a single file from a backup from AWS S3.
-     * @param destination The destination directory path for the file from the backup.
-     * @param backupKey The S3 key of the backup.
-     * @param fileName The full name of the file to restore (including directories if it was under a subdirectory).
-     */
-    suspend fun restoreFile(
-        destination: Path,
-        backupKey: String,
-        fileName: String,
-    ) = coroutineScope {
         // For byte ranges refer to https://pkware.cachefly.net/webdocs/APPNOTE/APPNOTE-6.3.9.TXT
-        val eocdReq =
+        val eocdReq = GetObjectRequest {
-            GetObjectRequest {
             bucket = bucketName
             key = backupKey
             // Assumption: EOCD has an empty comment
@@ -149,17 +117,14 @@ class BackupClient(
             //             in which case this function would error anyway, so it should be fine to have this edge-case.
             range = "bytes=-${EndOfCentralDirectoryRecord.SIZE + EndOfCentralDirectoryLocator.SIZE}"
         }
-        val eocdBytes =
+        val eocdBytes = s3.getObject(eocdReq) { resp ->
-            s3.getObject(eocdReq) { resp ->
             val bytes = resp.body?.toByteArray() ?: throw IOException("S3 response is missing body")
             bytes
         }
         val eocd = EndOfCentralDirectoryRecord.fromByteArray(eocdBytes, EndOfCentralDirectoryLocator.SIZE)
-        val eocd64 =
+        val eocd64 = if (eocd.eocd64Required()) {
-            if (eocd.eocd64Required()) {
             val locator = EndOfCentralDirectoryLocator.fromByteArray(eocdBytes, 0)
-                val eocd64Req =
+            val eocd64Req = GetObjectRequest {
-                    GetObjectRequest {
                 bucket = bucketName
                 key = backupKey
                 range = "bytes=${locator.endOfCentralDirectory64Offset}-"
@@ -168,25 +133,18 @@ class BackupClient(
                 val bytes = resp.body?.toByteArray() ?: throw IOException("S3 response is missing body")
                 EndOfCentralDirectoryRecord64.fromByteArray(bytes, 0)
             }
-            } else {
+        } else null
-                null
+        val cenOffset = if (eocd.centralDirectoryOffset == 0xffffffffU && eocd64 != null) {
-            }
-        val cenOffset =
-            if (eocd.centralDirectoryOffset == 0xffffffffU && eocd64 != null) {
             eocd64.centralDirectoryOffset
-            } else {
+        } else eocd.centralDirectoryOffset.toULong()
-                eocd.centralDirectoryOffset.toULong()
+        val censReq = GetObjectRequest {
-            }
-        val censReq =
-            GetObjectRequest {
             bucket = bucketName
             key = backupKey
             // We only know where to fetch until if we've also fetched EOCD64 (which isn't always the case).
             // So just over-fetch a little bit, these headers aren't that big anyway.
-                range = "bytes=$cenOffset-"
+            range = "bytes=${cenOffset}-"
         }
-        val cen =
+        val cen = s3.getObject(censReq) { resp ->
-            s3.getObject(censReq) { resp ->
             val bytes = resp.body?.toByteArray() ?: throw IOException("S3 response is missing body")
             var p = 0
             while (p < bytes.size) {
@@ -194,26 +152,23 @@ class BackupClient(
                     val cen = CentralDirectoryFileHeader.fromByteArray(bytes, p)
                     p += cen.size
                     if (cen.fileName == fileName) return@getObject cen
-                    } catch (_: InvalidDataException) {
+                } catch (_: InvalidSignatureException) {
                     return@getObject null
                 }
             }
             null
-            } ?: throw FileNotFoundException("File '$fileName' not found in backup")
+        } ?: throw FileNotFoundException("File '${fileName}' not found in backup")
 
-        val localHeaderOffset =
+        val localHeaderOffset = cen.extraFieldRecords.firstNotNullOfOrNull {
-            cen.extraFieldRecords.firstNotNullOfOrNull {
             if (it is Zip64ExtraFieldRecord && it.localHeaderOffset != null) it else null
         }?.localHeaderOffset ?: cen.localHeaderOffset.toULong()
-        val compressedSize =
+        val compressedSize = cen.extraFieldRecords.firstNotNullOfOrNull {
-            cen.extraFieldRecords.firstNotNullOfOrNull {
             if (it is Zip64ExtraFieldRecord && it.compressedSize != null) it else null
         }?.compressedSize ?: cen.compressedSize.toULong()
-        val req =
+        val req = GetObjectRequest {
-            GetObjectRequest {
             bucket = bucketName
             key = backupKey
-                range = "bytes=$localHeaderOffset-${
+            range = "bytes=${localHeaderOffset}-${
                 // Add CEN min size (46 bytes) so that the next CEN / LOC header is seen by the ZipInputStream
                 // and so it can see the current entry has stopped.
                 // Note: yes ZipInputStream should know the exact content length from the LOC, but it was still sending
@@ -224,20 +179,15 @@ class BackupClient(
         s3.getObject(req) { resp ->
             ZipInputStream(
                 resp.body?.toInputStream()
-                    ?: throw IOException("S3 response is missing body"),
+                    ?: throw IOException("S3 response is missing body")
             ).use { zipStream ->
-                zipStream.decompress(limit = 1) { name -> destination.resolve(name.takeLastWhile { it != '/' }) }
+                zipStream.decompress { name -> destination.resolve(name.takeLastWhile { it != '/' }) }
             }
         }
     }
 }
 
-/**
+private fun UploadPartResponse.asCompletedPart(number: Int): CompletedPart {
- * Convert an UploadPartResponse to a CompletedPart.
- * @param number The part number that was used for this part upload.
- * @return The CompletedPart object.
- */
-private fun UploadPartResponse.toCompletedPart(number: Int): CompletedPart {
     val part = this
     return CompletedPart {
         partNumber = number
@@ -249,29 +199,16 @@ private fun UploadPartResponse.toCompletedPart(number: Int): CompletedPart {
     }
 }
 
-/**
- * Take first `n` items from the beginning of a ByteArray.
- * @param n The number of items to take.
- * @return A ByteArray of the first `n` items.
- */
 private fun ByteArray.take(n: Int) =
-    if (n == size) {
+    if (n == size) this // No copy
-        this // No copy
+    else asList().subList(0, n).toByteArray() // TODO: One copy (toByteArray()), not sure how to do 0 copies here
-    } else {
-        asList().subList(0, n).toByteArray() // TODO: One copy (toByteArray()), not sure how to do 0 copies here
-    }
 
-/**
+private fun File.compressToZip(outputStream: OutputStream) = ZipOutputStream(outputStream).use { zipStream ->
- * Compress a file or directory as a ZIP file to an `OutputStream`.
+    val parentDir = this.absoluteFile.parent + "/"
- * @param outputStream The `OutputStream` to write the ZIP file contents to.
- */
-private fun File.compressToZip(outputStream: OutputStream) =
-    ZipOutputStream(outputStream).use { zipStream ->
-        val parentDir = this.canonicalFile.parent + "/"
     val fileQueue = ArrayDeque<File>()
     fileQueue.add(this)
     fileQueue.forEach { subFile ->
-            val path = subFile.canonicalPath.removePrefix(parentDir)
+        val path = subFile.absolutePath.removePrefix(parentDir)
         val subFiles = subFile.listFiles()
         if (subFiles != null) { // Is a directory
             val entry = ZipEntry("$path/")
@@ -289,18 +226,11 @@ private fun File.compressToZip(outputStream: OutputStream) =
     }
 }
 
-/**
- * Decompress `ZipInputStream` contents to specified destination paths.
- * @param bufSize The buffer size to use for writing the decompressed files.
- * @param entryNameToPath A function to convert ZIP entry names to destination `Path`s.
- */
 private fun ZipInputStream.decompress(
     bufSize: Int = 1024 * 1024,
-    limit: Int? = null,
+    entryNameToPath: (String) -> Path
-    entryNameToPath: (String) -> Path,
 ) {
     var entry = this.nextEntry
-    var count = 1
     while (entry != null) {
         val path = entryNameToPath(entry.name)
         if (entry.isDirectory) {
@@ -316,22 +246,11 @@ private fun ZipInputStream.decompress(
             }
         }
         applyZipAttributes(entry, path)
-        // This is here, not in while loop, since we do not want to read more from the input stream.
-        // But this.nextEntry will read from the input stream.
-        if (limit != null && count++ >= limit) return
         entry = this.nextEntry
     }
 }
 
-/**
+private fun setZipAttributes(entry: ZipEntry, path: Path) {
- * Set a `ZipEntry`'s attributes given a file's path.
- * @param entry The `ZipEntry` to set attributes of.
- * @param path The `Path` of the file to get the attributes from.
- */
-private fun setZipAttributes(
-    entry: ZipEntry,
-    path: Path,
-) {
     try {
         val attrs = Files.getFileAttributeView(path, BasicFileAttributeView::class.java).readAttributes()
         entry.setCreationTime(attrs.creationTime())
@@ -341,15 +260,7 @@ private fun setZipAttributes(
     }
 }
 
-/**
+private fun applyZipAttributes(entry: ZipEntry, path: Path) {
- * Set a file's attributes given a `ZipEntry`.
- * @param entry The `ZipEntry` to get the attributes from.
- * @param path The `Path` of the file to set the attributes of.
- */
-private fun applyZipAttributes(
-    entry: ZipEntry,
-    path: Path,
-) {
     try {
         val attrs = Files.getFileAttributeView(path, BasicFileAttributeView::class.java)
         attrs.setTimes(entry.lastModifiedTime, entry.lastAccessTime, entry.creationTime)

src/main/kotlin/backup/main.kt

@@ -0,0 +1,14 @@
+package backup
+
+import aws.sdk.kotlin.services.s3.S3Client
+import aws.sdk.kotlin.services.s3.model.ListBucketsRequest
+import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.runBlocking
+import java.io.File
+import kotlin.io.path.Path
+
+fun main() = runBlocking {
+    S3Client.fromEnvironment().use { s3 ->
+        val backupClient = BackupClient(s3, "teamcity-executors-test-task", 1024 * 1024 * 10)
+    }
+}

src/main/kotlin/ziputils/CentralDirectoryFileHeader.kt

@@ -3,9 +3,6 @@ package ziputils
 import java.nio.ByteBuffer
 import java.nio.ByteOrder
 
-/**
- * Represents a partial ZIP central directory file header.
- */
 internal class CentralDirectoryFileHeader(
     val compressedSize: UInt,
     val uncompressedSize: UInt,
@@ -15,7 +12,7 @@ internal class CentralDirectoryFileHeader(
     val disk: UShort,
     val localHeaderOffset: UInt,
     val fileName: String,
-    val extraFieldRecords: List<ExtraFieldRecord>,
+    val extraFieldRecords: List<ExtraFieldRecord>
 ) {
     val size: Int
         get() = SIZE + nameLength.toInt() + extraFieldLength.toInt() + commentLength.toInt()
@@ -25,92 +22,69 @@ internal class CentralDirectoryFileHeader(
         const val SIZE = 46
 
         /**
-         * Create `CentralDirectoryFileHeader` from raw byte data.
+         * Create CentralDirectoryFileHeader from raw byte data.
-         * @throws InvalidDataException provided `ByteArray` is not a supported CEN.
+         * @throws InvalidDataException provided ByteArray is not a supported CEN.
-         * @param data Raw byte data.
-         * @param offset Skip first <offset> bytes in data array.
-         * @return A `CentralDirectoryFileHeader`.
          */
         @Throws(InvalidDataException::class)
-        fun fromByteArray(
+        fun fromByteArray(data: ByteArray, offset: Int): CentralDirectoryFileHeader {
-            data: ByteArray,
-            offset: Int,
-        ): CentralDirectoryFileHeader {
             if (data.size - offset < SIZE) {
                 throw InvalidDataException("CEN must be at least 46 bytes")
             }
             val buf = ByteBuffer.wrap(data, offset, 46).order(ByteOrder.LITTLE_ENDIAN)
             if (buf.getInt().toUInt() != SIGNATURE) {
-                throw InvalidDataException("Invalid signature")
+                throw InvalidSignatureException("Invalid signature")
             }
 
             val extraFieldRecords = mutableListOf<ExtraFieldRecord>()
             val nameLength = buf.getShort(offset + 28).toUShort()
             buf.position(offset + 20)
-            val cen =
+            val cen = CentralDirectoryFileHeader(
-                CentralDirectoryFileHeader(
                 compressedSize = buf.getInt().toUInt(),
                 uncompressedSize = buf.getInt().toUInt(),
-                    nameLength =
+                nameLength = nameLength
-                        nameLength
                     .also { buf.position(offset + 30) },
                 extraFieldLength = buf.getShort().toUShort(),
                 commentLength = buf.getShort().toUShort(),
-                    disk =
+                disk = buf.getShort().toUShort()
-                        buf.getShort().toUShort()
                     .also { buf.position(offset + 42) },
                 localHeaderOffset = buf.getInt().toUInt(),
                 fileName = String(data.sliceArray(offset + SIZE..<offset + SIZE + nameLength.toInt())),
-                    extraFieldRecords = extraFieldRecords,
+                extraFieldRecords = extraFieldRecords
             )
             if (data.size - offset < cen.size) {
                 throw InvalidDataException("CEN is too short")
             }
 
             // Parse extra field records
-            val extraFieldsBuf =
+            val extraFieldsBuf = ByteBuffer.wrap(
-                ByteBuffer.wrap(
+                data, offset + SIZE + cen.nameLength.toInt(), cen.extraFieldLength.toInt()
-                    data,
-                    offset + SIZE + cen.nameLength.toInt(),
-                    cen.extraFieldLength.toInt(),
             ).order(ByteOrder.LITTLE_ENDIAN)
             while (extraFieldsBuf.remaining() > 0) {
                 val id = extraFieldsBuf.getShort().toUShort()
                 val size = extraFieldsBuf.getShort().toUShort()
-                extraFieldRecords.add(
+                extraFieldRecords.add(when (id) {
-                    when (id) {
                     Zip64ExtraFieldRecord.ID -> {
                         Zip64ExtraFieldRecord(
                             size,
                             if (cen.uncompressedSize == 0xffffffffU) {
                                 extraFieldsBuf.getLong().toULong()
-                                } else {
+                            } else null,
-                                    null
-                                },
                             if (cen.compressedSize == 0xffffffffU) {
                                 extraFieldsBuf.getLong().toULong()
-                                } else {
+                            } else null,
-                                    null
-                                },
                             if (cen.localHeaderOffset == 0xffffffffU) {
                                 extraFieldsBuf.getLong().toULong()
-                                } else {
+                            } else null,
-                                    null
-                                },
                             if (cen.disk == 0xffffU.toUShort()) {
                                 extraFieldsBuf.getInt().toUInt()
-                                } else {
+                            } else null
-                                    null
-                                },
                         )
                     }
-
                     else -> {
                         extraFieldsBuf.position(extraFieldsBuf.position() + size.toInt())
                         ExtraFieldRecord(id, size)
                     }
-                    },
+                })
-                )
             }
 
             return cen

src/main/kotlin/ziputils/EndOfCentralDirectoryLocator.kt

@@ -3,34 +3,20 @@ package ziputils
 import java.nio.ByteBuffer
 import java.nio.ByteOrder
 
-/**
- * Represents a partial ZIP64 end of central directory locator.
- */
 internal class EndOfCentralDirectoryLocator(
-    val endOfCentralDirectory64Offset: ULong,
+    val endOfCentralDirectory64Offset: ULong
 ) {
     companion object {
         const val SIGNATURE = 0x07064b50U
         const val SIZE = 20
-
-        /**
-         * Create `EndOfCentralDirectoryLocator` from raw byte data.
-         * @throws InvalidDataException Provided `ByteArray` is not a supported EOCD locator.
-         * @param data Raw byte data.
-         * @param offset Skip first <offset> bytes in data array.
-         * @return A `EndOfCentralDirectoryLocator`.
-         */
         @Throws(InvalidDataException::class)
-        fun fromByteArray(
+        fun fromByteArray(data: ByteArray, offset: Int): EndOfCentralDirectoryLocator {
-            data: ByteArray,
-            offset: Int,
-        ): EndOfCentralDirectoryLocator {
             if (data.size - offset < SIZE) {
                 throw InvalidDataException("EOCD64 locator must be at least 20 bytes")
             }
             val buf = ByteBuffer.wrap(data, offset, SIZE).order(ByteOrder.LITTLE_ENDIAN)
             if (buf.getInt().toUInt() != SIGNATURE) {
-                throw InvalidDataException("Invalid signature")
+                throw InvalidSignatureException("Invalid signature")
             }
             buf.position(offset + 8)
             return EndOfCentralDirectoryLocator(buf.getLong().toULong())

src/main/kotlin/ziputils/EndOfCentralDirectoryRecord.kt

@@ -4,39 +4,34 @@ import java.nio.ByteBuffer
 import java.nio.ByteOrder
 
 /**
- * Represents a partial ZIP end of central directory record.
+ * Partial End of Central Directory record class.
+ * Only supports data required by the backup tool.
  */
 internal class EndOfCentralDirectoryRecord(
-    val centralDirectoryOffset: UInt,
+    val centralDirectoryOffset: UInt
 ) {
-    fun eocd64Required(): Boolean = centralDirectoryOffset == 0xffffffffU
+    fun eocd64Required(): Boolean =
+        centralDirectoryOffset == 0xffffffffU
 
     companion object {
         const val SIGNATURE = 0x06054b50U
         const val SIZE = 22
-
         /**
-         * Create `EndOfCentralDirectoryRecord` from raw byte data.
+         * Create EndOfCentralDirectoryRecord from raw byte data.
-         * @throws InvalidDataException Provided `ByteArray` is not a supported EOCD64.
+         * @throws InvalidDataException provided ByteArray is not a supported EOCD64.
-         * @param data Raw byte data.
-         * @param offset Skip first <offset> bytes in data array.
-         * @return A `EndOfCentralDirectoryRecord`.
          */
         @Throws(InvalidDataException::class)
-        fun fromByteArray(
+        fun fromByteArray(data: ByteArray, offset: Int): EndOfCentralDirectoryRecord {
-            data: ByteArray,
-            offset: Int,
-        ): EndOfCentralDirectoryRecord {
             if (data.size - offset < SIZE) {
                 throw InvalidDataException("EOCD must be at least 22 bytes")
             }
             val buf = ByteBuffer.wrap(data, offset, SIZE).order(ByteOrder.LITTLE_ENDIAN)
             if (buf.getInt().toUInt() != SIGNATURE) {
-                throw InvalidDataException("Invalid signature")
+                throw InvalidSignatureException("Invalid signature")
             }
             buf.position(offset + 16)
             return EndOfCentralDirectoryRecord(
-                centralDirectoryOffset = buf.getInt().toUInt(),
+                centralDirectoryOffset = buf.getInt().toUInt()
             )
         }
     }

src/main/kotlin/ziputils/EndOfCentralDirectoryRecord64.kt

@@ -4,37 +4,31 @@ import java.nio.ByteBuffer
 import java.nio.ByteOrder
 
 /**
- * Represents a partial ZIP64 end of central directory record.
+ * Partial End of Central Directory record (ZIP64) class.
+ * Only supports data required by the backup tool.
  */
 internal class EndOfCentralDirectoryRecord64(
-    val centralDirectoryOffset: ULong,
+    val centralDirectoryOffset: ULong
 ) {
     companion object {
         const val SIGNATURE = 0x06064b50U
         const val SIZE = 56
-
         /**
-         * Create `EndOfCentralDirectoryRecord64` from raw byte data.
+         * Create EndOfCentralDirectoryRecord64 from raw byte data.
-         * @throws InvalidDataException Provided `ByteArray` is not a supported EOCD.
+         * @throws InvalidDataException provided ByteArray is not a supported EOCD.
-         * @param data Raw byte data.
-         * @param offset Skip first <offset> bytes in data array.
-         * @return A `EndOfCentralDirectoryRecord64`.
          */
         @Throws(InvalidDataException::class)
-        fun fromByteArray(
+        fun fromByteArray(data: ByteArray, offset: Int): EndOfCentralDirectoryRecord64 {
-            data: ByteArray,
-            offset: Int,
-        ): EndOfCentralDirectoryRecord64 {
             if (data.size - offset < SIZE) {
                 throw InvalidDataException("EOCD64 must be at least 56 bytes")
             }
             val buf = ByteBuffer.wrap(data, offset, SIZE).order(ByteOrder.LITTLE_ENDIAN)
             if (buf.getInt().toUInt() != SIGNATURE) {
-                throw InvalidDataException("Invalid signature")
+                throw InvalidSignatureException("Invalid signature")
             }
             buf.position(offset + 48)
             return EndOfCentralDirectoryRecord64(
-                centralDirectoryOffset = buf.getLong().toULong(),
+                centralDirectoryOffset = buf.getLong().toULong()
             )
         }
     }

src/main/kotlin/ziputils/Exceptions.kt

@@ -0,0 +1,4 @@
+package ziputils
+
+class InvalidDataException(message: String): Exception(message)
+class InvalidSignatureException(message: String): Exception(message)

src/main/kotlin/ziputils/ExtraFieldRecord.kt

@@ -1,9 +1,6 @@
 package ziputils
 
-/**
- * Represents a partial ZIP extra field record.
- */
 internal open class ExtraFieldRecord(
     val id: UShort,
-    val size: UShort,
+    val size: UShort
 )

src/main/kotlin/ziputils/InvalidDataException.kt

@@ -1,6 +0,0 @@
-package ziputils
-
-/**
- * Represents an invalid raw byte data exception.
- */
-class InvalidDataException(message: String) : Exception(message)

src/main/kotlin/ziputils/Zip64ExtraFieldRecord.kt

@@ -1,14 +1,11 @@
 package ziputils
 
-/**
- * Represents a ZIP ZIP64 extra field record (ID 0x0001).
- */
 internal class Zip64ExtraFieldRecord(
     size: UShort,
     val uncompressedSize: ULong?,
     val compressedSize: ULong?,
     val localHeaderOffset: ULong?,
-    val disk: UInt?,
+    val disk: UInt?
 ): ExtraFieldRecord(ID, size) {
     companion object {
         const val ID: UShort = 0x0001U