[ML] Make datafeeds work with nanosecond time fields (#51180)

Allows ML datafeeds to work with time fields that have
the "date_nanos" type _and make use of the extra precision_.
(Previously datafeeds only worked with time fields that were
exact multiples of milliseconds.  So datafeeds would work
with "date_nanos" only if the extra precision over "date" was
not used.)

Relates #49889

x-pack/plugin/ml/qa/basic-multi-node/src/test/java/org/elasticsearch/xpack/ml/integration/MlBasicMultiNodeIT.java

@@ -17,6 +17,7 @@ import org.elasticsearch.xpack.ml.MachineLearning;
 import org.yaml.snakeyaml.util.UriEncoder;
 
 import java.io.IOException;
+import java.io.UncheckedIOException;
 import java.util.Collections;
 import java.util.List;
 import java.util.Map;
@@ -36,7 +37,7 @@ public class MlBasicMultiNodeIT extends ESRestTestCase {
         assertTrue((Boolean) ml.get("enabled"));
     }
 
-    public void testInvalidJob() throws Exception {
+    public void testInvalidJob() {
         // The job name is invalid because it contains a space
         String jobId = "invalid job";
         ResponseException e = expectThrows(ResponseException.class, () -> createFarequoteJob(jobId));
@@ -103,11 +104,15 @@ public class MlBasicMultiNodeIT extends ESRestTestCase {
     }
 
     public void testMiniFarequoteWithDatafeeder() throws Exception {
+        boolean datesHaveNanoSecondResolution = randomBoolean();
+        String dateMappingType = datesHaveNanoSecondResolution ? "date_nanos" : "date";
+        String dateFormat = datesHaveNanoSecondResolution ? "strict_date_optional_time_nanos" : "strict_date_optional_time";
+        String randomNanos = datesHaveNanoSecondResolution ? "," + randomIntBetween(100000000, 999999999) : "";
         Request createAirlineDataRequest = new Request("PUT", "/airline-data");
         createAirlineDataRequest.setJsonEntity("{"
                 + "  \"mappings\": {"
                 + "    \"properties\": {"
-                + "      \"time\": { \"type\":\"date\"},"
+                + "      \"time\": { \"type\":\"" + dateMappingType + "\", \"format\":\"" + dateFormat + "\"},"
                 + "      \"airline\": { \"type\":\"keyword\"},"
                 + "      \"responsetime\": { \"type\":\"float\"}"
                 + "    }"
@@ -115,10 +120,10 @@ public class MlBasicMultiNodeIT extends ESRestTestCase {
                 + "}");
         client().performRequest(createAirlineDataRequest);
         Request airlineData1 = new Request("PUT", "/airline-data/_doc/1");
-        airlineData1.setJsonEntity("{\"time\":\"2016-06-01T00:00:00Z\",\"airline\":\"AAA\",\"responsetime\":135.22}");
+        airlineData1.setJsonEntity("{\"time\":\"2016-06-01T00:00:00" + randomNanos + "Z\",\"airline\":\"AAA\",\"responsetime\":135.22}");
         client().performRequest(airlineData1);
         Request airlineData2 = new Request("PUT", "/airline-data/_doc/2");
-        airlineData2.setJsonEntity("{\"time\":\"2016-06-01T01:59:00Z\",\"airline\":\"AAA\",\"responsetime\":541.76}");
+        airlineData2.setJsonEntity("{\"time\":\"2016-06-01T01:59:00" + randomNanos + "Z\",\"airline\":\"AAA\",\"responsetime\":541.76}");
         client().performRequest(airlineData2);
 
         // Ensure all data is searchable
@@ -147,7 +152,7 @@ public class MlBasicMultiNodeIT extends ESRestTestCase {
                 assertEquals(2, dataCountsDoc.get("input_record_count"));
                 assertEquals(2, dataCountsDoc.get("processed_record_count"));
             } catch (IOException e) {
-                throw new RuntimeException(e);
+                throw new UncheckedIOException(e);
             }
         });
 
@@ -233,7 +238,7 @@ public class MlBasicMultiNodeIT extends ESRestTestCase {
         assertEquals(1000, responseBody2.get("bucket_count"));
 
         // unintuitive: should return the earliest record timestamp of this feed???
-        assertEquals(null, responseBody2.get("earliest_record_timestamp"));
+        assertNull(responseBody2.get("earliest_record_timestamp"));
         assertEquals(1407082000000L, responseBody2.get("latest_record_timestamp"));
 
         assertEquals(Collections.singletonMap("closed", true),

x-pack/plugin/ml/src/main/java/org/elasticsearch/xpack/ml/datafeed/extractor/scroll/TimeBasedExtractedFields.java

@@ -61,7 +61,7 @@ public class TimeBasedExtractedFields extends ExtractedFields {
         List<String> remainingFields = job.allInputFields().stream().filter(f -> !f.equals(timeField)).collect(Collectors.toList());
         List<ExtractedField> allExtractedFields = new ArrayList<>(remainingFields.size() + 1);
         allExtractedFields.add(timeExtractedField);
-        remainingFields.stream().forEach(field -> allExtractedFields.add(extractionMethodDetector.detect(field)));
+        remainingFields.forEach(field -> allExtractedFields.add(extractionMethodDetector.detect(field)));
 
         return new TimeBasedExtractedFields(timeExtractedField, allExtractedFields);
     }

x-pack/plugin/ml/src/main/java/org/elasticsearch/xpack/ml/extractor/ExtractedFields.java

@@ -94,7 +94,7 @@ public class ExtractedFields {
         }
 
         private ExtractedField detectNonScriptField(String field) {
-            if (isFieldOfType(field, TimeField.TYPE) && isAggregatable(field)) {
+            if (isFieldOfTypes(field, TimeField.TYPES) && isAggregatable(field)) {
                 return new TimeField(field, ExtractedField.Method.DOC_VALUE);
             }
             if (isFieldOfType(field, GeoPointField.TYPE)) {
@@ -129,9 +129,14 @@ public class ExtractedFields {
         }
 
         private boolean isFieldOfType(String field, String type) {
+            return isFieldOfTypes(field, Collections.singleton(type));
+        }
+
+        private boolean isFieldOfTypes(String field, Set<String> types) {
+            assert types.isEmpty() == false;
             Map<String, FieldCapabilities> fieldCaps = fieldsCapabilities.getField(field);
-            if (fieldCaps != null && fieldCaps.size() == 1) {
+            if (fieldCaps != null && fieldCaps.isEmpty() == false) {
-                return fieldCaps.containsKey(type);
+                return types.containsAll(fieldCaps.keySet());
             }
             return false;
         }

x-pack/plugin/ml/src/main/java/org/elasticsearch/xpack/ml/extractor/TimeField.java

@@ -5,6 +5,7 @@
  */
 package org.elasticsearch.xpack.ml.extractor;
 
+import org.elasticsearch.common.util.set.Sets;
 import org.elasticsearch.search.SearchHit;
 
 import java.util.Collections;
@@ -13,15 +14,17 @@ import java.util.Set;
 
 public class TimeField extends AbstractField {
 
-    static final String TYPE = "date";
+    static final Set<String> TYPES = Collections.unmodifiableSet(Sets.newHashSet("date", "date_nanos"));
-
-    private static final Set<String> TYPES = Collections.singleton(TYPE);
 
     private static final String EPOCH_MILLIS_FORMAT = "epoch_millis";
 
     private final Method method;
 
     public TimeField(String name, Method method) {
+        // This class intentionally reports the possible types rather than the types reported by
+        // field caps at the point of construction.  This means that it will continue to work if,
+        // for example, a newly created index has a "date_nanos" time field when in all the indices
+        // that matched the pattern when this constructor was called the field had type "date".
         super(name, TYPES);
         if (method == Method.SOURCE) {
             throw new IllegalArgumentException("time field [" + name + "] cannot be extracted from source");
@@ -41,7 +44,23 @@ public class TimeField extends AbstractField {
             return value;
         }
         if (value[0] instanceof String) { // doc_value field with the epoch_millis format
-            value[0] = Long.parseLong((String) value[0]);
+            // Since nanosecond support was added epoch_millis timestamps may have a fractional component.
+            // We discard this, taking just whole milliseconds.  Arguably it would be better to retain the
+            // precision here and let the downstream component decide whether it wants the accuracy, but
+            // that makes it hard to pass around the value as a number.  The double type doesn't have
+            // enough digits of accuracy, and obviously long cannot store the fraction.  BigDecimal would
+            // work, but that isn't supported by the JSON parser if the number gets round-tripped through
+            // JSON.  So String is really the only format that could be used, but the ML consumers of time
+            // are expecting a number.
+            String strVal0 = (String) value[0];
+            int dotPos = strVal0.indexOf('.');
+            if (dotPos == -1) {
+                value[0] = Long.parseLong(strVal0);
+            } else if (dotPos > 0) {
+                value[0] = Long.parseLong(strVal0.substring(0, dotPos));
+            } else {
+                value[0] = 0L;
+            }
         } else if (value[0] instanceof Long == false) { // pre-6.0 field
             throw new IllegalStateException("Unexpected value for a time field: " + value[0].getClass());
         }

x-pack/plugin/ml/src/test/java/org/elasticsearch/xpack/ml/extractor/TimeFieldTests.java

@@ -5,33 +5,61 @@
  */
 package org.elasticsearch.xpack.ml.extractor;
 
+import org.elasticsearch.common.time.DateFormatter;
 import org.elasticsearch.search.SearchHit;
 import org.elasticsearch.test.ESTestCase;
 import org.elasticsearch.xpack.ml.test.SearchHitBuilder;
 
-import static org.hamcrest.Matchers.contains;
+import java.time.Instant;
+
+import static org.hamcrest.Matchers.containsInAnyOrder;
 import static org.hamcrest.Matchers.equalTo;
 import static org.hamcrest.Matchers.is;
 import static org.hamcrest.Matchers.startsWith;
 
 public class TimeFieldTests extends ESTestCase {
 
-    public void testDocValueWithStringValue() {
+    public void testDocValueWithWholeMillisecondStringValue() {
-        long millis = randomLong();
+        long millis = randomNonNegativeLong();
-        SearchHit hit = new SearchHitBuilder(randomInt()).addField("time", Long.toString(millis)).build();
+        Instant time = Instant.ofEpochMilli(millis);
+        DateFormatter formatter = DateFormatter.forPattern("epoch_millis");
+        String timeAsString = formatter.format(time);
+        SearchHit hit = new SearchHitBuilder(randomInt()).addField("time", timeAsString).build();
 
         ExtractedField timeField = new TimeField("time", ExtractedField.Method.DOC_VALUE);
 
         assertThat(timeField.value(hit), equalTo(new Object[] { millis }));
         assertThat(timeField.getName(), equalTo("time"));
         assertThat(timeField.getSearchField(), equalTo("time"));
-        assertThat(timeField.getTypes(), contains("date"));
+        assertThat(timeField.getTypes(), containsInAnyOrder("date", "date_nanos"));
         assertThat(timeField.getMethod(), equalTo(ExtractedField.Method.DOC_VALUE));
         assertThat(timeField.getDocValueFormat(), equalTo("epoch_millis"));
         assertThat(timeField.supportsFromSource(), is(false));
-        expectThrows(UnsupportedOperationException.class, () -> timeField.newFromSource());
+        expectThrows(UnsupportedOperationException.class, timeField::newFromSource);
         assertThat(timeField.isMultiField(), is(false));
-        expectThrows(UnsupportedOperationException.class, () -> timeField.getParentField());
+        expectThrows(UnsupportedOperationException.class, timeField::getParentField);
+    }
+
+    public void testDocValueWithFractionalMillisecondStringValue() {
+        long millis = randomNonNegativeLong();
+        int extraNanos = randomIntBetween(1, 999999);
+        Instant time = Instant.ofEpochMilli(millis).plusNanos(extraNanos);
+        DateFormatter formatter = DateFormatter.forPattern("epoch_millis");
+        String timeAsString = formatter.format(time);
+        SearchHit hit = new SearchHitBuilder(randomInt()).addField("time", timeAsString).build();
+
+        ExtractedField timeField = new TimeField("time", ExtractedField.Method.DOC_VALUE);
+
+        assertThat(timeField.value(hit), equalTo(new Object[] { millis }));
+        assertThat(timeField.getName(), equalTo("time"));
+        assertThat(timeField.getSearchField(), equalTo("time"));
+        assertThat(timeField.getTypes(), containsInAnyOrder("date", "date_nanos"));
+        assertThat(timeField.getMethod(), equalTo(ExtractedField.Method.DOC_VALUE));
+        assertThat(timeField.getDocValueFormat(), equalTo("epoch_millis"));
+        assertThat(timeField.supportsFromSource(), is(false));
+        expectThrows(UnsupportedOperationException.class, timeField::newFromSource);
+        assertThat(timeField.isMultiField(), is(false));
+        expectThrows(UnsupportedOperationException.class, timeField::getParentField);
     }
 
     public void testScriptWithLongValue() {
@@ -43,13 +71,13 @@ public class TimeFieldTests extends ESTestCase {
         assertThat(timeField.value(hit), equalTo(new Object[] { millis }));
         assertThat(timeField.getName(), equalTo("time"));
         assertThat(timeField.getSearchField(), equalTo("time"));
-        assertThat(timeField.getTypes(), contains("date"));
+        assertThat(timeField.getTypes(), containsInAnyOrder("date", "date_nanos"));
         assertThat(timeField.getMethod(), equalTo(ExtractedField.Method.SCRIPT_FIELD));
-        expectThrows(UnsupportedOperationException.class, () -> timeField.getDocValueFormat());
+        expectThrows(UnsupportedOperationException.class, timeField::getDocValueFormat);
         assertThat(timeField.supportsFromSource(), is(false));
-        expectThrows(UnsupportedOperationException.class, () -> timeField.newFromSource());
+        expectThrows(UnsupportedOperationException.class, timeField::newFromSource);
         assertThat(timeField.isMultiField(), is(false));
-        expectThrows(UnsupportedOperationException.class, () -> timeField.getParentField());
+        expectThrows(UnsupportedOperationException.class, timeField::getParentField);
     }
 
     public void testUnknownFormat() {