Add EpochConverter for milliseconds/seconds since epoch (related to issue #968) (#1000)

duncanj · Duncan · web-flow · commit b65040a3b5d8 · 2026-01-16T11:01:52.000+01:00
* Add EpochConverter and pattern "ep", "epoch" (related to issue #968) Pattern "ep" or "epoch" supports milliseconds by default and also epoch{seconds} for people who need UNIX-style epoch timestamps in their logs. Signed-off-by: Duncan Jauncey <duncan@duncanjauncey.com> * Add copyright notice to EpochConverter and EpochConverterTest Signed-off-by: Duncan Jauncey <duncan@duncanjauncey.com> --------- Signed-off-by: Duncan Jauncey <duncan@duncanjauncey.com> Co-authored-by: Duncan <duncan@duncanjauncey.com>
diff --git a/logback-classic/src/main/java/ch/qos/logback/classic/PatternLayout.java b/logback-classic/src/main/java/ch/qos/logback/classic/PatternLayout.java
@@ -70,6 +70,10 @@ public class PatternLayout extends PatternLayoutBase<ILoggingEvent> {
         DEFAULT_CONVERTER_SUPPLIER_MAP.put("micros", MicrosecondConverter::new);
         CONVERTER_CLASS_TO_KEY_MAP.put(MicrosecondConverter.class.getName(), "micros");
 
+        DEFAULT_CONVERTER_SUPPLIER_MAP.put("ep", EpochConverter::new);
+        DEFAULT_CONVERTER_SUPPLIER_MAP.put("epoch", EpochConverter::new);
+        CONVERTER_CLASS_TO_KEY_MAP.put(EpochConverter.class.getName(), "epoch");
+
         DEFAULT_CONVERTER_SUPPLIER_MAP.put("r", RelativeTimeConverter::new);
         DEFAULT_CONVERTER_SUPPLIER_MAP.put("relative", RelativeTimeConverter::new);
         CONVERTER_CLASS_TO_KEY_MAP.put(RelativeTimeConverter.class.getName(), "relative");
diff --git a/logback-classic/src/main/java/ch/qos/logback/classic/pattern/EpochConverter.java b/logback-classic/src/main/java/ch/qos/logback/classic/pattern/EpochConverter.java
@@ -0,0 +1,28 @@
+/**
+ * Logback: the reliable, generic, fast and flexible logging framework.
+ * Copyright (C) 1999-2015, QOS.ch. All rights reserved.
+ *
+ * This program and the accompanying materials are dual-licensed under
+ * either the terms of the Eclipse Public License v1.0 as published by
+ * the Eclipse Foundation
+ *
+ *   or (per the licensee's choosing)
+ *
+ * under the terms of the GNU Lesser General Public License version 2.1
+ * as published by the Free Software Foundation.
+ */
+package ch.qos.logback.classic.pattern;
+
+import ch.qos.logback.classic.spi.ILoggingEvent;
+
+public class EpochConverter extends ClassicConverter {
+    @Override
+    public String convert(ILoggingEvent event) {
+        String millisOrSeconds = getFirstOption();
+        if ("seconds".equals(millisOrSeconds) ) {
+            return "" + (event.getTimeStamp() / 1000L);
+        }
+
+        return "" + event.getTimeStamp();
+    }
+}
diff --git a/logback-classic/src/test/java/ch/qos/logback/classic/PatternLayoutTest.java b/logback-classic/src/test/java/ch/qos/logback/classic/PatternLayoutTest.java
@@ -214,6 +214,28 @@ void verifyMicros(int nanos, String expected) {
         assertEquals(expected, val);
     }
 
+    @Test
+    public void epoch() {
+        verifyEpoch(123, false, "2026-01-15 10:15:30.123 1768472130123 Some message");
+        verifyEpoch(456, false, "2026-01-15 10:15:30.456 1768472130456 Some message");
+        verifyEpoch(123, true, "2026-01-15 10:15:30.123 1768472130 Some message");
+        verifyEpoch(456, true, "2026-01-15 10:15:30.456 1768472130 Some message");
+    }
+
+    void verifyEpoch(int millis, boolean secondsNotMillis, String expected) {
+        Instant instant = Instant.parse("2026-01-15T10:15:30Z");
+        instant = instant.plusMillis(millis);
+        LoggingEvent le = makeLoggingEvent(aMessage, null);
+        le.setInstant(instant);
+
+        String option = secondsNotMillis ? "{seconds}" : "";
+        pl.setPattern("%date{yyyy-MM-dd HH:mm:ss.SSS, UTC} %epoch"+option+" %message%nopex");
+        pl.start();
+
+        String val = pl.doLayout(le);
+        assertEquals(expected, val);
+    }
+
     @Override
     public Context getContext() {
         return loggerContext;
diff --git a/logback-classic/src/test/java/ch/qos/logback/classic/pattern/EpochConverterTest.java b/logback-classic/src/test/java/ch/qos/logback/classic/pattern/EpochConverterTest.java
@@ -0,0 +1,62 @@
+/**
+ * Logback: the reliable, generic, fast and flexible logging framework.
+ * Copyright (C) 1999-2015, QOS.ch. All rights reserved.
+ *
+ * This program and the accompanying materials are dual-licensed under
+ * either the terms of the Eclipse Public License v1.0 as published by
+ * the Eclipse Foundation
+ *
+ *   or (per the licensee's choosing)
+ *
+ * under the terms of the GNU Lesser General Public License version 2.1
+ * as published by the Free Software Foundation.
+ */
+package ch.qos.logback.classic.pattern;
+
+import ch.qos.logback.classic.spi.LoggingEvent;
+import org.junit.jupiter.api.Test;
+
+import java.time.Instant;
+import java.util.Collections;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
+public class EpochConverterTest {
+    EpochConverter ec = new EpochConverter();
+
+    @Test
+    public void withDefaultConfiguration() {
+        ec.setOptionList(null);
+        LoggingEvent le = new LoggingEvent();
+        Instant instant = Instant.parse("2026-01-15T10:15:30Z");
+        instant = instant.plusMillis(321);
+        le.setInstant(instant);
+
+        String result = ec.convert(le);
+        assertEquals("1768472130321", result); // includes millis
+    }
+
+    @Test
+    public void withSecondsConfiguration() {
+        ec.setOptionList(Collections.singletonList("seconds"));
+        LoggingEvent le = new LoggingEvent();
+        Instant instant = Instant.parse("2026-01-15T10:15:30Z");
+        instant = instant.plusMillis(321); // millis should be ignored
+        le.setInstant(instant);
+
+        String result = ec.convert(le);
+        assertEquals("1768472130", result);
+    }
+
+    @Test
+    public void withUnknownNonsenseConfiguration() {
+        ec.setOptionList(Collections.singletonList("nonsense"));
+        LoggingEvent le = new LoggingEvent();
+        Instant instant = Instant.parse("2026-01-15T10:15:30Z");
+        instant = instant.plusMillis(321);
+        le.setInstant(instant);
+
+        String result = ec.convert(le);
+        assertEquals("1768472130321", result); // includes millis, default behaviour
+    }
+}
