feat: add Transformer

Add Transformer and related classes

no-ticket

.gitignore

@@ -43,3 +43,5 @@ out/
 *.code-workspace
 # Local History for Visual Studio Code
 .history/
+.vscode/settings.json
+

src/main/java/to/wetransform/hale/transformer/CustomTarget.java

@@ -3,11 +3,20 @@
 import java.util.HashMap;
 import java.util.Map;
 
+import org.json.JSONObject;
+
 import eu.esdihumboldt.hale.common.core.io.Value;
 
 public record CustomTarget(String providerId, Map<String, Value> settings) {
 
-    public CustomTarget(String providerId) {
-        this(providerId, new HashMap<>());
-    }
+	public CustomTarget(String providerId) {
+		this(providerId, new HashMap<>());
+	}
+
+	public void setProviderId(String string) {
+	}
+
+	public JSONObject getSettings() {
+		return null;
+	}
 }

src/main/java/to/wetransform/hale/transformer/ResultCallbackHelper.java

@@ -0,0 +1,127 @@
+package to.wetransform.hale.transformer;
+
+import java.io.IOException;
+import java.io.OutputStream;
+import java.io.OutputStreamWriter;
+import java.net.HttpURLConnection;
+import java.net.URL;
+import java.nio.charset.StandardCharsets;
+import java.util.Optional;
+import java.util.zip.GZIPOutputStream;
+
+import org.json.JSONException;
+import org.json.JSONObject;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+/**
+ * Helper to perform transformation result callbacks.
+ */
+public class ResultCallbackHelper {
+
+	/**
+	 * The logger instance for this class.
+	 */
+	private static Logger logger = LoggerFactory.getLogger(ResultCallbackHelper.class);
+
+	/**
+	 * Perform the transformation result callback.
+	 *
+	 * @param success     Whether or not the transformation has been successful.
+	 * @param logs        The transformation log.
+	 * @param callbackUrl The callback url.
+	 * @param token       The jwt token for the request.
+	 * @param jobId       The transformation job id.
+	 */
+	public static void performResultCallback(boolean success, String logs, Optional<JSONObject> stats,
+			String callbackUrl, String token, Optional<String> jobId) {
+		try {
+			// Create transformation result object.
+			JSONObject resultObj = new JSONObject();
+			resultObj.put("success", success);
+
+			JSONObject propertiesObj = new JSONObject();
+			if (Optional.ofNullable(logs).isPresent()) {
+				propertiesObj.put("logs", logs);
+			}
+
+			if (jobId.isPresent()) {
+				propertiesObj.put("jobId", jobId.get());
+			} else {
+				logger.warn("Transformation result callback does not contain a jobId.");
+			}
+
+			if (stats.isPresent()) {
+				propertiesObj.put("stats", stats.get());
+			}
+
+			resultObj.put("properties", propertiesObj);
+
+			// Send result object to callback URL.
+			sendTransformationResult(resultObj, callbackUrl, token);
+
+		} catch (JSONException e) {
+			logger.warn("Failed to create result object to be sent ");
+		}
+	}
+
+	/**
+	 * Send the transformation result object to the given url.
+	 *
+	 * @param result The transformation result object.
+	 * @param url    The callback url.
+	 * @param token  The jwt token.
+	 */
+	private static void sendTransformationResult(JSONObject result, String url, String token) {
+
+		try {
+			logger.info("Sending transformation result to " + url.toString());
+
+			// Create http request to send result object.
+			URL sendUrl = new URL(url);
+			HttpURLConnection http = (HttpURLConnection) sendUrl.openConnection();
+			if (token != null) {
+				http.setRequestProperty("Authorization", "Bearer " + token);
+			} else {
+				logger.warn("Transformation callback is being performed without JWT token!");
+			}
+			http.setRequestProperty("Content-Type", "application/json; charset=UTF-8");
+			http.setRequestProperty("Content-Encoding", "gzip");
+			http.setDoOutput(true);
+			http.setDoInput(true);
+			http.setRequestMethod("PUT");
+			http.setConnectTimeout(10000);
+
+			// write zipped content
+			OutputStream os = http.getOutputStream();
+			OutputStream gzip = new GZIPOutputStream(os);
+
+			try {
+				OutputStreamWriter osw = new OutputStreamWriter(gzip, StandardCharsets.UTF_8);
+				osw.write(result.toString());
+				osw.flush();
+				osw.close();
+			} catch (IOException e) {
+				logger.warn("Failed to write result callback request body.", e);
+			} finally {
+				os.close();
+				gzip.close();
+			}
+
+			// handle http response
+			int statusCode = http.getResponseCode();
+			String statusMessage = http.getResponseMessage();
+			String resLogMsg = "Transformation result callback endpoint responded with status code " + statusCode + ": "
+					+ statusMessage;
+			if (statusCode != 200) {
+				logger.warn(resLogMsg);
+			} else {
+				logger.info(resLogMsg);
+			}
+
+			http.disconnect();
+		} catch (Throwable t) {
+			logger.warn("Failed to perform transformation result callback.", t);
+		}
+	}
+}

src/main/java/to/wetransform/hale/transformer/RunContext.java

@@ -0,0 +1,28 @@
+package to.wetransform.hale.transformer;
+
+import java.io.File;
+import java.io.IOException;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.util.ArrayList;
+import java.util.List;
+
+import org.apache.commons.io.FileUtils;
+
+public class RunContext {
+
+	private final List<Path> tempFiles = new ArrayList<>();
+
+	public File createTempDir() throws IOException {
+		Path path = Files.createTempDirectory("hale-progen");
+		tempFiles.add(path);
+		return path.toFile();
+	}
+
+	public void cleanUp() throws IOException {
+		for (Path path : tempFiles) {
+			FileUtils.deleteDirectory(path.toFile());
+		}
+		tempFiles.clear();
+	}
+}

src/main/java/to/wetransform/hale/transformer/SourceConfig.java

@@ -8,10 +8,10 @@
 
 import eu.esdihumboldt.hale.common.core.io.Value;
 
-public record SourceConfig(
-        URI location, String providerId, Map<String, Value> settings, boolean transform, List<String> attachments) {
+public record SourceConfig(URI location, String providerId, Map<String, Value> settings, boolean transform,
+		List<String> attachments) {
 
-    public SourceConfig(URI location, String providerId) {
-        this(location, providerId, new HashMap<>(), true, new ArrayList<>());
-    }
+	public SourceConfig(URI location, String providerId) {
+		this(location, providerId, new HashMap<>(), true, new ArrayList<>());
+	}
 }

src/main/java/to/wetransform/hale/transformer/TargetConfig.java

@@ -1,3 +1,4 @@
 package to.wetransform.hale.transformer;
 
-public record TargetConfig(String filename, String preset, CustomTarget customTarget) {}
+public record TargetConfig(String filename, String preset, CustomTarget customTarget) {
+}