SNRK-48: Add s3 implementation

Use common s3 api and '/'-separated keys to simulate directories

snark-storage-driver/src/main/kotlin/space/kscience/snark/storage/s3/Directory.kt

@@ -0,0 +1,41 @@
+package space.kscience.snark.storage.s3
+
+import aws.sdk.kotlin.services.s3.S3Client
+import space.kscience.snark.storage.Directory as Dir
+import space.kscience.snark.storage.FileReader
+import space.kscience.snark.storage.FileWriter
+import java.nio.file.Path
+
+public class Directory(
+    private val client: S3Client,
+    private val bucketName: String,
+    private val currentDir: String,
+) : Dir {
+    override suspend fun get(filename: String): FileReader = run {
+        S3FileReader(client, bucketName, "$currentDir/$filename")
+    }
+
+    override suspend fun create(filename: String, ignoreIfExists: Boolean) {
+        if (!ignoreIfExists) {
+            throw IllegalArgumentException("could not check if file exists")
+        }
+    }
+
+    override suspend fun put(filename: String): FileWriter = run {
+        S3FileWriter(client, bucketName, "$currentDir/$filename")
+    }
+
+    override suspend fun getSubdir(path: Path): Directory = run {
+        Directory(client, bucketName, "$currentDir/$path")
+    }
+
+    override suspend fun createSubdir(dirname: String, ignoreIfExists: Boolean): Directory = run {
+        if (!ignoreIfExists) {
+            throw IllegalArgumentException("could not check if directory exists")
+        }
+        Directory(client, bucketName, "$currentDir/$dirname")
+    }
+
+    override fun close() {
+    }
+}

snark-storage-driver/src/main/kotlin/space/kscience/snark/storage/s3/File.kt

@@ -0,0 +1,38 @@
+package space.kscience.snark.storage.s3
+
+import aws.sdk.kotlin.services.s3.S3Client
+import aws.sdk.kotlin.services.s3.model.GetObjectRequest
+import aws.sdk.kotlin.services.s3.putObject
+import aws.smithy.kotlin.runtime.content.ByteStream
+import aws.smithy.kotlin.runtime.content.toByteArray
+import space.kscience.snark.storage.FileReader
+import space.kscience.snark.storage.FileWriter
+
+public class S3FileReader(private val client: S3Client, private val bucketName: String, private val fullQualifiedPath: String) : FileReader {
+    override suspend fun readAll(): ByteArray {
+        val result = client.getObject(GetObjectRequest{
+            bucket = bucketName
+            key = fullQualifiedPath
+        }) {
+            it.body?.toByteArray() ?: ByteArray(0)
+        }
+        return result
+    }
+
+    override fun close() {
+    }
+}
+
+public class S3FileWriter(private val client: S3Client, private val bucketName: String, private val fullQualifiedPath: String) : FileWriter {
+    override suspend fun write(bytes: ByteArray) {
+        client.putObject {
+            bucket = bucketName
+            key = fullQualifiedPath
+            body = ByteStream.fromBytes(bytes)
+        }
+    }
+
+    override fun close() {
+    }
+
+}

snark-storage-driver/src/main/kotlin/space/kscience/snark/storage/s3/Root.kt

@@ -0,0 +1,46 @@
+package space.kscience.snark.storage.s3
+
+import aws.sdk.kotlin.services.s3.*
+import space.kscience.snark.storage.Directory as Dir
+import space.kscience.snark.storage.FileReader
+import space.kscience.snark.storage.FileWriter
+import java.io.File
+import java.lang.Exception
+import java.nio.file.Path
+
+public class Root(private val client: S3Client) : Dir {
+    override suspend fun get(filename: String): FileReader {
+        throw NoSuchFileException(File(filename))
+    }
+
+    override suspend fun create(filename: String, ignoreIfExists: Boolean) {
+        throw IllegalCallerException()
+    }
+
+    override suspend fun put(filename: String): FileWriter {
+        throw NoSuchFileException(File(filename))
+    }
+
+    override suspend fun getSubdir(path: Path): Directory = try {
+        val bucketName = path.toString()
+        client.headBucket {
+            bucket = bucketName
+        }
+        Directory(client, bucketName, "")
+    } catch (ex: Exception) {
+        throw java.nio.file.AccessDeniedException(path.toString()).initCause(ex)
+    }
+
+    override suspend fun createSubdir(dirname: String, ignoreIfExists: Boolean): Directory = try {
+        client.createBucket {
+            bucket = dirname
+        }
+        Directory(client, dirname, "")
+    } catch (ex: Exception) {
+        throw java.nio.file.AccessDeniedException(dirname).initCause(ex)
+    }
+
+    override fun close() {
+    }
+
+}