[7.17] Adjust date conversion for execution context in watcher compare condition (#88467)

* Add test of date math with ctx.execution_time

Add one test to confirm the below watcher compare condition is always
met.

```
  "condition": {
    "compare": {
      "ctx.execution_time": {
        "gte": "<{now-5m}>"
      }
    }
  }
```

v1 can be an instance of JodaCompatibleZonedDateTime in versions prior
to #78417, which has to be converted to ZonedDateTime for appropriate
comparison.

Closes #88408

Author: sakurai-youhei

docs/changelog/88467.yaml

@@ -0,0 +1,6 @@
+pr: 88467
+summary: Adjust date conversion for execution context in watcher compare condition
+area: Infra/Scripting
+type: bug
+issues:
+ - 88408

x-pack/plugin/watcher/src/main/java/org/elasticsearch/xpack/watcher/condition/LenientCompare.java

@@ -6,6 +6,7 @@
  */
 package org.elasticsearch.xpack.watcher.condition;
 
+import org.elasticsearch.script.JodaCompatibleZonedDateTime;
 import org.elasticsearch.xpack.core.watcher.support.WatcherDateTimeUtils;
 
 import java.time.Instant;
@@ -69,6 +70,9 @@ public static Integer compare(Object v1, Object v2) {
                 }
             } else if (v1 instanceof Number) {
                 v1 = Instant.ofEpochMilli(((Number) v1).longValue()).atZone(ZoneOffset.UTC);
+            } else if (v1 instanceof JodaCompatibleZonedDateTime) {
+                // this can only occur in versions prior to #78417
+                v1 = ((JodaCompatibleZonedDateTime) v1).getZonedDateTime();
             } else {
                 // cannot convert to date...
                 return null;

x-pack/plugin/watcher/src/test/java/org/elasticsearch/xpack/watcher/condition/CompareConditionTests.java

@@ -188,6 +188,17 @@ public void testExecuteDateMath() throws Exception {
         assertThat(condition.execute(ctx).met(), is(met));
     }
 
+    public void testExecuteDateMathExecutionContext() throws Exception {
+        ClockMock clock = ClockMock.frozen();
+        boolean met = true;
+        Op op = CompareCondition.Op.GTE;
+        String value = "<{now-5m}>";
+
+        CompareCondition condition = new CompareCondition("ctx.execution_time", op, value, clock);
+        WatchExecutionContext ctx = mockExecutionContext("_name", null);
+        assertThat(condition.execute(ctx).met(), is(met));
+    }
+
     public void testExecutePath() throws Exception {
         ClockMock clock = ClockMock.frozen();
         boolean met = randomBoolean();