Added support for 'epoch_micro' in date processor

data-prepper-plugins/date-processor/README.md

@@ -66,7 +66,7 @@ valid key and at least one pattern is required if match is configured.
     * `patterns`: List of possible patterns the timestamp value of key can have. The patterns are based on sequence of letters and symbols. 
       The `patterns` support all the patterns listed in Java 
       [DatetimeFormatter](https://docs.oracle.com/javase/8/docs/api/java/time/format/DateTimeFormatter.html).
-      and also supports `epoch_second`, `epoch_milli` and `epoch_nano` values which represents the timestamp as the number of seconds, milliseconds and nano seconds since epoch. Epoch values are always UTC time zone.
+      and also supports `epoch_second`, `epoch_milli`, `epoch_micro` and `epoch_nano` values which represents the timestamp as the number of seconds, milliseconds, microseconds and nano seconds since epoch. Epoch values are always UTC time zone.
       * Type: `List<String>`
 
 The following example of date configuration will use `timestamp` key to match against given patterns and stores the timestamp in ISO 8601

data-prepper-plugins/date-processor/src/main/java/org/opensearch/dataprepper/plugins/processor/date/DateProcessor.java

@@ -37,7 +37,7 @@ public class DateProcessor extends AbstractProcessor<Record<Event>, Record<Event
     private static final String OUTPUT_FORMAT = "yyyy-MM-dd'T'HH:mm:ss.SSSXXX";
     private static final int LENGTH_OF_EPOCH_IN_MILLIS = 13;
     private static final int LENGTH_OF_EPOCH_SECONDS = 10;
-
+    private static final int LENGTH_OF_EPOCH_MICROSECONDS = 16;
     static final String DATE_PROCESSING_MATCH_SUCCESS = "dateProcessingMatchSuccess";
     static final String DATE_PROCESSING_MATCH_FAILURE = "dateProcessingMatchFailure";
 
@@ -160,6 +160,9 @@ private Pair<String, Instant> getEpochFormatOutput(Instant time) {
             return Pair.of(Long.toString(time.getEpochSecond()), time);
         } else if (outputFormat.equals("epoch_milli")) {
             return Pair.of(Long.toString(time.toEpochMilli()), time);
+        } else if (outputFormat.equals("epoch_micro")) {
+            long micro = (long)time.getEpochSecond() * 1000_000 + (long) time.getNano() / 1000;
+            return Pair.of(Long.toString(micro), time);
         } else { // epoch_nano. validation for valid epoch_ should be
                  // done at init time
             long nano = (long)time.getEpochSecond() * 1000_000_000 + (long) time.getNano();
@@ -182,13 +185,20 @@ private Pair<String, Instant> getFormattedDateTimeString(final String sourceTime
         }
         if (numberValue != null) {
             int timestampLength = sourceTimestamp.length();
-            if (timestampLength > LENGTH_OF_EPOCH_IN_MILLIS) {
+            if (timestampLength > LENGTH_OF_EPOCH_MICROSECONDS) {
                 if (epochFormatters.contains("epoch_nano")) {
                     epochTime = Instant.ofEpochSecond(numberValue/1000_000_000, numberValue % 1000_000_000);
                 } else {
                     LOG.warn("Source time value is larger than epoch pattern configured. epoch_nano is expected but not present in the patterns list");
                     return null;
                 }
+            } else if (timestampLength > LENGTH_OF_EPOCH_IN_MILLIS) {
+                if (epochFormatters.contains("epoch_micro")) {
+                    epochTime = Instant.ofEpochSecond(numberValue/1000_000, (numberValue % 1000_000) * 1000);
+                } else {
+                    LOG.warn("Source time value is larger than epoch pattern configured. epoch_micro is expected but not present in the patterns list");
+                    return null;
+                }
             } else if (timestampLength > LENGTH_OF_EPOCH_SECONDS) {
                 if (epochFormatters.contains("epoch_milli")) {
                     epochTime = Instant.ofEpochMilli(numberValue);

data-prepper-plugins/date-processor/src/main/java/org/opensearch/dataprepper/plugins/processor/date/DateProcessorConfig.java

@@ -67,6 +67,7 @@ public boolean isValidPatterns() {
         public static boolean isValidPattern(final String pattern) {
             if (pattern.equals("epoch_second") ||
                 pattern.equals("epoch_milli") ||
+                pattern.equals("epoch_micro") ||
                 pattern.equals("epoch_nano")) {
                     return true;
             }

data-prepper-plugins/date-processor/src/test/java/org/opensearch/dataprepper/plugins/processor/date/DateProcessorConfigTest.java

@@ -80,6 +80,8 @@ void testValidAndInvalidOutputFormats() throws NoSuchFieldException, IllegalAcce
             assertThat(dateProcessorConfig.isValidOutputFormat(), equalTo(true));
             setField(DateProcessorConfig.class, dateProcessorConfig, "outputFormat", "epoch_nano");
             assertThat(dateProcessorConfig.isValidOutputFormat(), equalTo(true));
+            setField(DateProcessorConfig.class, dateProcessorConfig, "outputFormat", "epoch_micro");
+            assertThat(dateProcessorConfig.isValidOutputFormat(), equalTo(true));
             setField(DateProcessorConfig.class, dateProcessorConfig, "outputFormat", "epoch_xyz");
             assertThat(dateProcessorConfig.isValidOutputFormat(), equalTo(false));
             setField(DateProcessorConfig.class, dateProcessorConfig, "outputFormat", "yyyy-MM-dd'T'HH:mm:ss.nnnnnnnnnXXX");