1 files changed, 87 insertions, 0 deletions
diff --git a/src/main/java/com/google/devtools/build/lib/util/LoggingUtil.java b/src/main/java/com/google/devtools/build/lib/util/LoggingUtil.java
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index 0000000000..5170727c6e
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+++ b/src/main/java/com/google/devtools/build/lib/util/LoggingUtil.java
@@ -0,0 +1,87 @@
+// Copyright 2014 Google Inc. All rights reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//    http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package com.google.devtools.build.lib.util;
+
+import com.google.common.base.Preconditions;
+import com.google.common.util.concurrent.Uninterruptibles;
+import com.google.devtools.build.lib.concurrent.ThreadSafety;
+
+import java.util.concurrent.ExecutionException;
+import java.util.concurrent.Future;
+import java.util.logging.Level;
+import java.util.logging.LogRecord;
+import java.util.logging.Logger;
+
+/**
+ * Logging utilities for sending log messages to a remote service. Log messages
+ * will not be output anywhere else, including the terminal and blaze clients.
+ */
+@ThreadSafety.ThreadSafe
+public final class LoggingUtil {
+  // TODO(bazel-team): this class is a thin wrapper around Logger and could probably be discarded.
+  private static Future<Logger> remoteLogger;
+
+  /**
+   * Installs the remote logger.
+   *
+   * <p>This can only be called once, and the caller should not keep the
+   * reference to the logger.
+   *
+   * @param logger The logger future. Must have already started.
+   */
+  public static synchronized void installRemoteLogger(Future<Logger> logger) {
+    Preconditions.checkState(remoteLogger == null);
+    remoteLogger = logger;
+  }
+
+  /** Returns the installed logger, or null if none is installed. */
+  public static synchronized Logger getRemoteLogger() {
+    try {
+      return (remoteLogger == null) ? null : Uninterruptibles.getUninterruptibly(remoteLogger);
+    } catch (ExecutionException e) {
+      throw new RuntimeException("Unexpected error initializing remote logging", e);
+    }
+  }
+
+  /**
+   * @see #logToRemote(Level, String, Throwable, String...).
+   */
+  public static void logToRemote(Level level, String msg, Throwable trace) {
+    Logger logger = getRemoteLogger();
+    if (logger != null) {
+      logger.log(level, msg, trace);
+    }
+  }
+
+  /**
+   * Log a message to the remote backend.  This is done out of thread, so this
+   * method is non-blocking.
+   *
+   * @param level The severity level. Non null.
+   * @param msg The log message. Non null.
+   * @param trace The stack trace.  May be null.
+   * @param values Additional values to upload.
+   */
+  public static void logToRemote(Level level, String msg, Throwable trace,
+      String... values) {
+    Logger logger = getRemoteLogger();
+    if (logger != null) {
+      LogRecord logRecord = new LogRecord(level, msg);
+      logRecord.setThrown(trace);
+      logRecord.setParameters(values);
+      logger.log(logRecord);
+    }
+  }
+}