Adding test for execption with POST for invokeModel

Signed-off-by: TrungBui59 <[email protected]>

ml-algorithms/src/test/java/org/opensearch/ml/engine/algorithms/remote/HttpJsonConnectorExecutorTest.java

@@ -27,6 +27,7 @@
 import org.opensearch.ml.common.dataset.MLInputDataset;
 import org.opensearch.ml.common.dataset.TextDocsInputDataSet;
 import org.opensearch.ml.common.dataset.remote.RemoteInferenceInputDataSet;
+import org.opensearch.ml.common.exception.MLException;
 import org.opensearch.ml.common.input.MLInput;
 import org.opensearch.ml.common.output.model.ModelTensorOutput;
 import org.opensearch.ml.engine.httpclient.MLHttpClientFactory;
@@ -59,6 +60,22 @@ public void setUp() {
         MockitoAnnotations.openMocks(this);
     }
 
+    @Test
+    public void invokeRemoteModel_POSTMethodErrorPath() {
+        exceptionRule.expect(MLException.class);
+        exceptionRule.expectMessage("Failed to create http request for remote model");
+
+        ConnectorAction predictAction = ConnectorAction.builder()
+                .actionType(ConnectorAction.ActionType.PREDICT)
+                .method("post")
+                .url("wrong url")
+                .requestBody("{\"input\": \"${parameters.input}\"}")
+                .build();
+        Connector connector = HttpConnector.builder().name("test connector").version("1").protocol("http").actions(Arrays.asList(predictAction)).build();
+        HttpJsonConnectorExecutor executor = new HttpJsonConnectorExecutor(connector);
+        executor.invokeRemoteModel(null, null, null, null);
+    }
+
     @Test
     public void invokeRemoteModel_WrongHttpMethod() {
         exceptionRule.expect(IllegalArgumentException.class);