feat: Extend a set of options in WriteOption to allow defining the log location as custom project, folder, organization or billing account (#727)

* feat: Extend a set of options in WriteOption to allow defining the log location as custom project, folder, organization or billing account

* Fix a test and small refactor in writeLogEntriesRequest

* 🦉 Updates from OwlBot

See https://github.com/googleapis/repo-automation-bots/blob/main/packages/owl-bot/README.md

* Make sure we do not propagate project id from request to log entries during write() and fix tests accordingly to cover all cases

* Add an empty log entry to be tested with latest destination handling logic

* Address PR comments

* 🦉 Updates from OwlBot

See https://github.com/googleapis/repo-automation-bots/blob/main/packages/owl-bot/README.md

* Fix lint errors

* Address test related PR comments

Co-authored-by: Owl Bot <gcf-owl-bot[bot]@users.noreply.github.com>

Author: losalex

google-cloud-logging/src/main/java/com/google/cloud/logging/Logging.java

@@ -69,7 +69,8 @@ final class WriteOption extends Option {
     enum OptionType implements Option.OptionType {
       LOG_NAME,
       RESOURCE,
-      LABELS;
+      LABELS,
+      LOG_DESTINATION;
 
       @SuppressWarnings("unchecked")
       <T> T get(Map<Option.OptionType, ?> options) {
@@ -105,6 +106,14 @@ public static WriteOption resource(MonitoredResource resource) {
     public static WriteOption labels(Map<String, String> labels) {
       return new WriteOption(OptionType.LABELS, ImmutableMap.copyOf(labels));
     }
+
+    /**
+     * Returns an option to specify a log destination resource path (see {@link LogDestinationName}
+     * for details)
+     */
+    public static WriteOption destination(LogDestinationName destination) {
+      return new WriteOption(OptionType.LOG_DESTINATION, destination);
+    }
   }
 
   /** Fields according to which log entries can be sorted. */

google-cloud-logging/src/main/java/com/google/cloud/logging/LoggingHandler.java

@@ -22,7 +22,9 @@
 import com.google.cloud.logging.Logging.WriteOption;
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableMap;
+import com.google.common.collect.Iterables;
 import java.time.Instant;
+import java.util.ArrayList;
 import java.util.Collections;
 import java.util.LinkedList;
 import java.util.List;
@@ -172,7 +174,7 @@ public LoggingHandler(String log, LoggingOptions options) {
    *     a default resource is created based on the project ID and deployment environment.
    */
   public LoggingHandler(String log, LoggingOptions options, MonitoredResource monitoredResource) {
-    this(log, options, monitoredResource, null);
+    this(log, options, monitoredResource, null, null);
   }
 
   /**
@@ -190,6 +192,27 @@ public LoggingHandler(
       LoggingOptions options,
       MonitoredResource monitoredResource,
       List<LoggingEnhancer> enhancers) {
+    this(log, options, monitoredResource, enhancers, null);
+  }
+
+  /**
+   * Creates a handler that publishes messages to Cloud Logging.
+   *
+   * @param log the name of the log to which log entries are written
+   * @param options options for the Cloud Logging service
+   * @param monitoredResource the monitored resource to which log entries refer. If it is null then
+   *     a default resource is created based on the project ID and deployment environment.
+   * @param enhancers List of {@link LoggingEnhancer} instances used to enhance any{@link LogEntry}
+   *     instances built by this handler.
+   * @param destination the log destination {@link LogDestinationName} (see 'logName' parameter in
+   *     https://cloud.google.com/logging/docs/reference/v2/rest/v2/LogEntry)
+   */
+  public LoggingHandler(
+      String log,
+      LoggingOptions options,
+      MonitoredResource monitoredResource,
+      List<LoggingEnhancer> enhancers,
+      LogDestinationName destination) {
     try {
       loggingOptions = options != null ? options : LoggingOptions.getDefaultInstance();
       LoggingConfig config = new LoggingConfig(getClass().getName());
@@ -204,17 +227,20 @@ public LoggingHandler(
       MonitoredResource resource =
           firstNonNull(
               monitoredResource, config.getMonitoredResource(loggingOptions.getProjectId()));
-      defaultWriteOptions =
-          new WriteOption[] {
-            WriteOption.logName(logName),
-            WriteOption.resource(resource),
-            WriteOption.labels(
-                ImmutableMap.of(
-                    LEVEL_NAME_KEY,
-                    baseLevel.getName(),
-                    LEVEL_VALUE_KEY,
-                    String.valueOf(baseLevel.intValue())))
-          };
+      List<WriteOption> writeOptions = new ArrayList<WriteOption>();
+      writeOptions.add(WriteOption.logName(logName));
+      writeOptions.add(WriteOption.resource(resource));
+      writeOptions.add(
+          WriteOption.labels(
+              ImmutableMap.of(
+                  LEVEL_NAME_KEY,
+                  baseLevel.getName(),
+                  LEVEL_VALUE_KEY,
+                  String.valueOf(baseLevel.intValue()))));
+      if (destination != null) {
+        writeOptions.add(WriteOption.destination(destination));
+      }
+      defaultWriteOptions = Iterables.toArray(writeOptions, WriteOption.class);
 
       getLogging().setFlushSeverity(severityFor(flushLevel));
       getLogging().setWriteSynchronicity(config.getSynchronicity());

google-cloud-logging/src/main/java/com/google/cloud/logging/LoggingImpl.java

@@ -21,6 +21,7 @@
 import static com.google.cloud.logging.Logging.ListOption.OptionType.PAGE_SIZE;
 import static com.google.cloud.logging.Logging.ListOption.OptionType.PAGE_TOKEN;
 import static com.google.cloud.logging.Logging.WriteOption.OptionType.LABELS;
+import static com.google.cloud.logging.Logging.WriteOption.OptionType.LOG_DESTINATION;
 import static com.google.cloud.logging.Logging.WriteOption.OptionType.LOG_NAME;
 import static com.google.cloud.logging.Logging.WriteOption.OptionType.RESOURCE;
 
@@ -738,11 +739,13 @@ private static WriteLogEntriesRequest writeLogEntriesRequest(
       LoggingOptions serviceOptions,
       Iterable<LogEntry> logEntries,
       Map<Option.OptionType, ?> options) {
-    String projectId = serviceOptions.getProjectId();
     WriteLogEntriesRequest.Builder builder = WriteLogEntriesRequest.newBuilder();
-    String logName = LOG_NAME.get(options);
+    String projectId = serviceOptions.getProjectId();
+
+    LogName logName = getLogName(projectId, LOG_NAME.get(options), LOG_DESTINATION.get(options));
+
     if (logName != null) {
-      builder.setLogName(LogName.ofProjectLogName(projectId, logName).toString());
+      builder.setLogName(logName.toString());
     }
     MonitoredResource resource = RESOURCE.get(options);
     if (resource != null) {
@@ -752,10 +755,25 @@ private static WriteLogEntriesRequest writeLogEntriesRequest(
     if (labels != null) {
       builder.putAllLabels(labels);
     }
+
     builder.addAllEntries(Iterables.transform(logEntries, LogEntry.toPbFunction(projectId)));
     return builder.build();
   }
 
+  private static LogName getLogName(
+      String projectId, String logName, LogDestinationName destination) {
+    if (logName == null) {
+      return null;
+    }
+
+    // If no destination specified, fallback to project based log name
+    if (destination == null) {
+      return LogName.ofProjectLogName(projectId, logName);
+    }
+
+    return destination.toLogName(logName);
+  }
+
   public void write(Iterable<LogEntry> logEntries, WriteOption... options) {
     if (inWriteCall.get() != null) {
       return;

google-cloud-logging/src/test/java/com/google/cloud/logging/LoggingHandlerTest.java

@@ -310,6 +310,28 @@ public void testPublishCustomResource() {
     handler.publish(newLogRecord(Level.FINEST, MESSAGE));
   }
 
+  @Test
+  public void testPublishCustomResourceWithFolder() {
+    testPublishCustomResourceWithDestination(FINEST_ENTRY, LogDestinationName.folder("folder"));
+  }
+
+  @Test
+  public void testPublishCustomResourceWithBilling() {
+    testPublishCustomResourceWithDestination(
+        FINEST_ENTRY, LogDestinationName.billingAccount("billing"));
+  }
+
+  @Test
+  public void testPublishCustomResourceWithOrganization() {
+    testPublishCustomResourceWithDestination(
+        FINEST_ENTRY, LogDestinationName.organization("organization"));
+  }
+
+  @Test
+  public void testPublishCustomResourceWithProject() {
+    testPublishCustomResourceWithDestination(FINEST_ENTRY, LogDestinationName.project(PROJECT));
+  }
+
   @Test
   public void testPublishKubernetesContainerResource() {
     expect(options.getProjectId()).andReturn(PROJECT).anyTimes();
@@ -582,4 +604,27 @@ public void testClose() throws Exception {
     handler.close();
     handler.close();
   }
+
+  private void testPublishCustomResourceWithDestination(
+      LogEntry entry, LogDestinationName destination) {
+    expect(options.getProjectId()).andReturn(PROJECT).anyTimes();
+    expect(options.getService()).andReturn(logging);
+    logging.setFlushSeverity(Severity.ERROR);
+    expectLastCall().once();
+    logging.setWriteSynchronicity(Synchronicity.ASYNC);
+    expectLastCall().once();
+    MonitoredResource resource = MonitoredResource.of("custom", ImmutableMap.<String, String>of());
+    logging.write(
+        ImmutableList.of(entry),
+        WriteOption.logName(LOG_NAME),
+        WriteOption.resource(resource),
+        WriteOption.labels(BASE_SEVERITY_MAP),
+        WriteOption.destination(destination));
+    expectLastCall().once();
+    replay(options, logging);
+    Handler handler = new LoggingHandler(LOG_NAME, options, resource, null, destination);
+    handler.setLevel(Level.ALL);
+    handler.setFormatter(new TestFormatter());
+    handler.publish(newLogRecord(Level.FINEST, MESSAGE));
+  }
 }