Fix #1647: support negative CqlDuration/duration values

src/main/java/io/stargate/sgv2/jsonapi/service/operation/filters/table/codecs/CqlDurationConverter.java

@@ -22,7 +22,21 @@ public static String toISO8601Duration(CqlDuration value) {
     int days = value.getDays();
     long nanoSeconds = value.getNanoseconds();
 
-    final StringBuilder sb = new StringBuilder("P");
+    // Negative value? To detect see if any value negative (all must be 0 or negative
+    // if one is -- but `CqlDuration` ensures that invariant). Bit silly there's no
+    // `CqlDuration.isNegative()` (or `CqlDuration.negate()` to create opposite value)
+    // or such but it is what it is.
+    final StringBuilder sb;
+    boolean negative = (months < 0) || (days < 0) || (nanoSeconds < 0L);
+    if (negative) {
+      // and if we do have negative value, we need to prepend minus sign, negate all parts
+      sb = new StringBuilder("-P");
+      months = -months;
+      days = -days;
+      nanoSeconds = -nanoSeconds;
+    } else {
+      sb = new StringBuilder("P");
+    }
 
     // Do we have date part?
     if (months > 0 || days > 0) { // yes

src/main/java/io/stargate/sgv2/jsonapi/service/operation/filters/table/codecs/JSONCodecs.java

@@ -244,7 +244,7 @@ public abstract class JSONCodecs {
           GenericType.STRING,
           DataTypes.DURATION,
           // CqlDuration.from() accepts 2 formats; ISO-8601 ("P1H30M") and "1h30m" (Cassandra
-          // compact) format
+          // compact) format. Note: negative values (preceding "-") also accepted
           JSONCodec.ToCQL.safeFromString(CqlDuration::from),
           // But since we must produce ISO-8601, need custom JSON serialization
           (objectMapper, fromCQLType, value) ->

src/test/java/io/stargate/sgv2/jsonapi/api/v1/tables/InsertOneTableIntegrationTest.java

@@ -568,6 +568,35 @@ void insertEJSONTimestampValue() {
           .hasJSONField("data.document", outputJSON);
     }
 
+    @Test
+    void insertValidNegativeDurationValue() {
+      assertTableCommand(keyspaceName, TABLE_WITH_DATETIME_COLUMNS)
+          .templated()
+          .insertOne(
+                  """
+                    {
+                        "id": "%s",
+                        "durationValue": "%s"
+                    }
+                    """
+                  .formatted("datetimeNegDuration", "-8h10m"))
+          .wasSuccessful();
+      assertTableCommand(keyspaceName, TABLE_WITH_DATETIME_COLUMNS)
+          .postFindOne(
+              """
+                                  { "filter": { "id": "datetimeNegDuration" },
+                                    "projection": { "durationValue": 1 }
+                                  }
+                              """)
+          .wasSuccessful()
+          .hasJSONField(
+              "data.document",
+                  """
+                    { "durationValue": "%s" }
+                    """
+                  .formatted("-PT8H10M"));
+    }
+
     @Test
     void failOnInvalidDateValue() {
       assertTableCommand(keyspaceName, TABLE_WITH_DATETIME_COLUMNS)

src/test/java/io/stargate/sgv2/jsonapi/service/operation/filters/table/codecs/JSONCodecRegistryTest.java

@@ -259,6 +259,15 @@ private static Stream<Arguments> validCodecToCQLTestCasesDatetime() {
             DataTypes.DURATION,
             TEST_DATA.DURATION_VALID_STR_ISO8601,
             CqlDuration.from(TEST_DATA.DURATION_VALID_STR_ISO8601)),
+        // Should also support negative duration values:
+        Arguments.of(
+            DataTypes.DURATION,
+            "-" + TEST_DATA.DURATION_VALID_STR_CASS,
+            CqlDuration.from("-" + TEST_DATA.DURATION_VALID_STR_CASS)),
+        Arguments.of(
+            DataTypes.DURATION,
+            "-" + TEST_DATA.DURATION_VALID_STR_ISO8601,
+            CqlDuration.from("-" + TEST_DATA.DURATION_VALID_STR_ISO8601)),
         Arguments.of(
             DataTypes.TIME, TEST_DATA.TIME_VALID_STR, LocalTime.parse(TEST_DATA.TIME_VALID_STR)),
         Arguments.of(
@@ -578,6 +587,11 @@ private static Stream<Arguments> validCodecToJSONTestCasesDatetime() {
             DataTypes.DURATION,
             CqlDuration.from(TEST_DATA.DURATION_VALID_STR_CASS),
             JSONS.textNode(TEST_DATA.DURATION_VALID_STR_ISO8601)),
+        // And then negative variant of same duration
+        Arguments.of(
+            DataTypes.DURATION,
+            CqlDuration.from("-" + TEST_DATA.DURATION_VALID_STR_CASS),
+            JSONS.textNode("-" + TEST_DATA.DURATION_VALID_STR_ISO8601)),
         Arguments.of(
             DataTypes.TIME,
             LocalTime.parse(TEST_DATA.TIME_VALID_STR),