Add test to verify setting of SemaphoreKey and MutexName fields in DSL

Signed-off-by: ddalvi <[email protected]>

sdk/python/kfp/compiler/compiler_test.py

@@ -3847,6 +3847,66 @@ def outer():
                 foo_platform_set_bar_feature(task, 12)
 
 
+class TestPipelineSemaphoreMutex(unittest.TestCase):
+
+    def test_pipeline_with_semaphore(self):
+        """Test that pipeline config correctly sets the semaphore key."""
+        config = PipelineConfig()
+        config.set_semaphore_key('semaphore')
+
+        @dsl.pipeline(pipeline_config=config)
+        def my_pipeline():
+            task = comp()
+
+        with tempfile.TemporaryDirectory() as tempdir:
+            output_yaml = os.path.join(tempdir, 'pipeline.yaml')
+            compiler.Compiler().compile(
+                pipeline_func=my_pipeline, package_path=output_yaml
+            )
+
+            with open(output_yaml, 'r') as f:
+                pipeline_docs = list(yaml.safe_load_all(f))
+
+        pipeline_spec = None
+        for doc in pipeline_docs:
+            if 'platforms' in doc:
+                pipeline_spec = doc
+                break
+
+        if pipeline_spec:
+            kubernetes_spec = pipeline_spec['platforms']['kubernetes']['pipelineConfig']
+            assert kubernetes_spec['semaphoreKey'] == 'semaphore'
+            self.assertNotIn('mutexName', kubernetes_spec)
+
+    def test_pipeline_with_mutex(self):
+        """Test that pipeline config correctly sets the mutex name."""
+        config = PipelineConfig()
+        config.set_mutex_name('mutex')
+
+        @dsl.pipeline(pipeline_config=config)
+        def my_pipeline():
+            task = comp()
+
+        with tempfile.TemporaryDirectory() as tempdir:
+            output_yaml = os.path.join(tempdir, 'pipeline.yaml')
+            compiler.Compiler().compile(
+                pipeline_func=my_pipeline, package_path=output_yaml
+            )
+
+            with open(output_yaml, 'r') as f:
+                pipeline_docs = list(yaml.safe_load_all(f))
+
+        pipeline_spec = None
+        for doc in pipeline_docs:
+            if 'platforms' in doc:
+                pipeline_spec = doc
+                break
+
+        if pipeline_spec:
+            kubernetes_spec = pipeline_spec['platforms']['kubernetes']['pipelineConfig']
+            assert kubernetes_spec['mutexName'] == 'mutex'
+
+
 class ExtractInputOutputDescription(unittest.TestCase):
 
     def test_no_descriptions(self):

sdk/python/kfp/dsl/pipeline_config.py

@@ -24,8 +24,16 @@ def __init__(self):
     def set_semaphore_key(self, semaphore_key: str):
         """Set the name of the semaphore to control pipeline concurrency.
 
+        The semaphore is configured via a ConfigMap. By default, the ConfigMap is
+        named "semaphore-config", but this name can be specified through the APIServer
+        deployment manifests using an environment variable named SEMAPHORE_CONFIGMAP_NAME.
+        If the environment variable is not specified, the default name "semaphore-config"
+        is used. The semaphore key is provided through the pipeline configuration.
+        If a pipeline has a semaphore, the backend maps the semaphore to the ConfigMap
+        using the key provided by the user.
+
         Args:
-            semaphore_key (str): Name of the semaphore.
+            semaphore_key (str): The key used to map to the ConfigMap.
         """
         self.semaphore_key = semaphore_key.strip()