1 files changed, 136 insertions, 0 deletions
diff --git a/vespalog/src/main/java/com/yahoo/log/VespaLogHandler.java b/vespalog/src/main/java/com/yahoo/log/VespaLogHandler.java
new file mode 100644
index 00000000000..26208340132
--- /dev/null
+++ b/vespalog/src/main/java/com/yahoo/log/VespaLogHandler.java
@@ -0,0 +1,136 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.log;
+
+import java.io.UnsupportedEncodingException;
+import java.util.logging.Level;
+import java.util.logging.LogRecord;
+import java.util.logging.StreamHandler;
+
+/**
+ * @author  Bjorn Borud
+ * @author arnej27959
+ */
+class VespaLogHandler extends StreamHandler {
+
+    private final LogTarget logTarget;
+    private final String serviceName;
+    private final String appPrefix;
+    private final LevelControllerRepo repo;
+    private final RejectFilter logRejectFilter;
+
+    /**
+     * Construct handler which logs to specified logTarget.  The logTarget
+     * may be of the following formats:
+     *
+     * <DL>
+     *  <DT> <code>fd:&lt;number&gt;</code>
+     *  <DD> Log to specified file descriptor number.  Only "fd:2"
+     *       is supported.
+     *
+     *  <DT> <code>file:&lt;filename&gt;</code>
+     *  <DD> Log to specified file in append mode
+     * </DL>
+     */
+    public VespaLogHandler(LogTarget logTarget,
+                           LevelControllerRepo levelControllerRepo, String serviceName,
+                           String applicationPrefix) {
+        this.logTarget = logTarget;
+        this.serviceName = serviceName;
+        this.appPrefix = applicationPrefix;
+        this.repo = levelControllerRepo;
+        this.logRejectFilter = RejectFilter.createDefaultRejectFilter();
+        initialize();
+    }
+
+    /**
+     * Publish a log record into the Vespa log target.
+     */
+    public synchronized void publish (LogRecord record) {
+        Level level = record.getLevel();
+        String component = record.getLoggerName();
+
+        LevelController ctrl = getLevelControl(component);
+        if (!ctrl.shouldLog(level)) {
+            return;
+        }
+
+        if (logRejectFilter.shouldReject(record.getMessage())) {
+            return;
+        }
+
+        try {
+            // provokes rotation of target
+            setOutputStream(logTarget.open());
+        } catch (RuntimeException e) {
+            LogRecord r = new LogRecord(Level.SEVERE,
+                                            "Unable to open file target");
+            r.setThrown(e);
+            emergencyLog(r);
+            setOutputStream(System.err);
+        }
+        super.publish(record);
+        flush();
+        closeFileTarget();
+    }
+
+    public LevelController getLevelControl(String component) {
+        return repo.getLevelController(component);
+    }
+
+    /**
+     * Initalize the handler.  The main invariant is that
+     * outputStream is always set to something valid when this method
+     * returns.
+     */
+    private void initialize () {
+        try {
+            setFormatter(new VespaFormatter(serviceName, appPrefix));
+            setLevel(LogLevel.ALL);
+            setEncoding("UTF-8");
+            // System.err.println("initialize vespa logging, default level: "+defaultLogLevel);
+            setOutputStream(logTarget.open());
+        }
+        catch (UnsupportedEncodingException uee) {
+            LogRecord r = new LogRecord(Level.SEVERE, "Unable to set log encoding to UTF-8");
+            r.setThrown(uee);
+            emergencyLog(r);
+        }
+        catch (RuntimeException e) {
+            LogRecord r = new LogRecord(Level.SEVERE,
+                    "Unable to open file target");
+            r.setThrown(e);
+            emergencyLog(r);
+            setOutputStream(System.err);
+        }
+    }
+
+
+    /** Closes the target log file, if there is one */
+    public void closeFileTarget() {
+        try {
+            logTarget.close();
+        }
+        catch (RuntimeException e) {
+            LogRecord r = new LogRecord(Level.WARNING, "Unable to close log");
+            r.setThrown(e);
+            emergencyLog(r);
+        }
+    }
+
+    /**
+     * If the logging system experiences problems we can't be expected
+     * to log it through normal channels, so we have an emergency log
+     * method which just uses STDERR for formatting the log messages.
+     * (Which might be right, and might be wrong).
+     *
+     * @param record The log record to be logged
+     */
+    private void emergencyLog(LogRecord record) {
+        record.setLoggerName(VespaLogHandler.class.getName());
+        System.err.println(getFormatter().format(record));
+    }
+
+    public void cleanup() {
+        repo.close();
+    }
+}