fix(cloudwatch): reject PutMetricData datums without a MetricName (#6072)

* fix(cloudwatch): reject PutMetricData datums without a MetricName MetricName is the one required member of MetricDatum. The JSON handler stored a nameless datum under an empty name, and the Query handler treated a member without MetricName as the end of the list, silently dropping it and every later datum while still storing the earlier ones. Both handlers now reject a missing or empty MetricName in top-level MetricData and in EntityMetricData[].MetricData with MissingParameter (400), the error PutMetricData declares for a missing required input, naming the offending member. A whitespace name is still accepted, since AWS constrains MetricName only to 1 to 255 characters. Every datum is validated before any is stored, so a rejected request leaves no state behind. On Query, a member index with no keys at all still ends that MetricData list. * fix(cloudwatch): return MissingRequiredParameterException on JSON and CBOR CloudWatch is awsQueryCompatible. MissingParameter is the awsQueryError code of the MissingRequiredParameterException shape, so it belongs in the Query <Code> and the x-amzn-query-error header, while a JSON 1.0 or CBOR body's __type names the shape. With the code in __type the AWS SDK v2 raised a generic CloudWatchException instead of the modelled one. A package-private CloudWatchMetricsException keeps the Query code as its error code and overrides jsonType() with the shape name, the same split SwfException makes. The shared query-code table in AwsException is left alone because SQS reports MissingParameter as its JSON type. (cherry picked from commit b8d87df05413ea8c4f9497fa05f388c19d4124ec)
2026-10-20 19:37:57 +05:30
parent e90978ae94
commit 24314f4432
8 changed files with 260 additions and 7 deletions
@@ -233,4 +233,20 @@ class CloudWatchTest {
        assertThat(stats.datapoints()).hasSize(1);
        assertThat(stats.datapoints().get(0).sum()).isEqualTo(6.5);
    }
+
+    @Test
+    @DisplayName("PutMetricData without MetricName throws MissingRequiredParameterException")
+    void testPutMetricDataWithoutMetricNameIsRejected() {
+        String namespace = "JavaTestMissingMetricName";
+
+        assertThatThrownBy(() -> cloudWatchClient.putMetricData(request -> request
+                .namespace(namespace)
+                .entityMetricData(entityMetricData -> entityMetricData
+                        .metricData(MetricDatum.builder().value(1.0).build()))))
+                .isInstanceOf(MissingRequiredParameterException.class)
+                .satisfies(e -> assertThat(((MissingRequiredParameterException) e).awsErrorDetails().errorCode())
+                        .isEqualTo("MissingParameter"));
+
+        assertThat(cloudWatchClient.listMetrics(request -> request.namespace(namespace)).metrics()).isEmpty();
+    }
 }