Github user zentol commented on a diff in the pull request:
https://github.com/apache/flink/pull/5115#discussion_r155178904
--- Diff:
flink-runtime/src/test/java/org/apache/flink/runtime/metrics/groups/MetricGroupTest.java
---
@@ -78,6 +81,138 @@ public void sameGroupOnNameCollision() {
assertTrue(subgroup1 == subgroup2);
}
+ @Test
+ public void createGroupWithUserDefinedVariables() {
+ GenericMetricGroup group = new GenericMetricGroup(
+ registry, new DummyAbstractMetricGroup(registry),
"somegroup");
+
+ String keyName = "sometestkey";
+ String valueName1 = "sometestvalue1";
+ MetricGroup subgroup1 = group.addGroup(keyName, valueName1);
+ Map<String, String> variables1 = subgroup1.getAllVariables();
+
+ assertNotNull(subgroup1);
+ assertEquals(GenericValueMetricGroup.class,
subgroup1.getClass());
+ assertEquals(GenericKeyMetricGroup.class,
((AbstractMetricGroup) subgroup1).parent.getClass());
+
assertTrue(variables1.containsKey(ScopeFormat.asVariable(keyName)));
+ assertEquals(valueName1,
variables1.get(ScopeFormat.asVariable(keyName)));
+
+ String valueName2 = "sometestvalue2";
+ MetricGroup subgroup2 = group.addGroup(keyName, valueName2);
+ Map<String, String> variables2 = subgroup2.getAllVariables();
+
+ assertNotNull(subgroup2);
+ assertEquals(GenericValueMetricGroup.class,
subgroup2.getClass());
+ assertEquals(((AbstractMetricGroup) subgroup1).parent,
((AbstractMetricGroup) subgroup2).parent);
+
assertTrue(variables2.containsKey(ScopeFormat.asVariable(keyName)));
+ assertEquals(valueName2,
variables2.get(ScopeFormat.asVariable(keyName)));
+ }
+
+ @Test
+ public void
forbidToCreateGenericKeyMetricGroupAfterGenericKeyMetricGroup() {
+ GenericMetricGroup group = new GenericMetricGroup(
+ registry, new DummyAbstractMetricGroup(registry),
"somegroup");
+
+ String keyName = "somekeyname";
+ String valueName = "somevaluename";
+ group.addGroup(keyName, valueName);
+
+ String keyName2 = "somekeyname2";
+ String valueName2 = "somevaluename2";
+ MetricGroup subgroup =
group.addGroup(keyName).addGroup(keyName2, valueName2);
+
+ // Is is illegal to call `MetricGroup#addGroup(String key,
String value)` after `GenericKeyMetricGroup`.
+ // The behavior will fall back to
`group.addGroup(key).addGroup(value)`.
+ assertEquals(GenericMetricGroup.class, ((AbstractMetricGroup)
subgroup).parent.getClass());
--- End diff --
The problem with this test and many others that were added is that they
test implementation details instead of behavior. We shouldn't check whether the
parent is a GenericMetricGroup or a GenericKeyMetricGroup, but instead how the
scope/variables are affected.
---
