Add high-level workflow describe

Author: Quinn-With-Two-Ns

temporal-sdk/src/main/java/io/temporal/client/WorkflowExecutionDescription.java

@@ -0,0 +1,41 @@
+/*
+ * Copyright (C) 2022 Temporal Technologies, Inc. All Rights Reserved.
+ *
+ * Copyright (C) 2012-2016 Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ *
+ * Modifications copyright (C) 2017 Uber Technologies, Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this material except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package io.temporal.client;
+
+import io.temporal.api.workflowservice.v1.DescribeWorkflowExecutionResponse;
+import io.temporal.common.converter.DataConverter;
+import javax.annotation.Nonnull;
+
+/** Contains information about a workflow execution. */
+public class WorkflowExecutionDescription extends WorkflowExecutionMetadata {
+  private final @Nonnull DescribeWorkflowExecutionResponse response;
+
+  public WorkflowExecutionDescription(
+      @Nonnull DescribeWorkflowExecutionResponse response, @Nonnull DataConverter dataConverter) {
+    super(response.getWorkflowExecutionInfo(), dataConverter);
+    this.response = response;
+  }
+
+  /** Returns the raw response from the Temporal service. */
+  public DescribeWorkflowExecutionResponse getRawDescription() {
+    return response;
+  }
+}

temporal-sdk/src/main/java/io/temporal/client/WorkflowStub.java

@@ -382,6 +382,16 @@ <R> CompletableFuture<R> getResultAsync(
    */
   void terminate(@Nullable String reason, Object... details);
 
+  /**
+   * Get the current description of this workflow.
+   *
+   * @throws WorkflowNotFoundException if the workflow execution doesn't exist
+   * @throws WorkflowServiceException for all other failures including networking and service
+   *     availability issues
+   * @return the current description of this workflow
+   */
+  WorkflowExecutionDescription describe();
+
   Optional<WorkflowOptions> getOptions();
 
   /**

temporal-sdk/src/main/java/io/temporal/client/WorkflowStubImpl.java

@@ -446,6 +446,21 @@ public void terminate(@Nullable String reason, Object... details) {
     }
   }
 
+  @Override
+  public WorkflowExecutionDescription describe() {
+    checkStarted();
+    WorkflowExecution targetExecution = execution.get();
+    try {
+      WorkflowClientCallsInterceptor.DescribeWorkflowOutput result =
+          workflowClientInvoker.describe(
+              new WorkflowClientCallsInterceptor.DescribeWorkflowInput(targetExecution));
+      return result.getDescription();
+    } catch (Exception e) {
+      Throwable failure = throwAsWorkflowFailureException(e, targetExecution);
+      throw new WorkflowServiceException(targetExecution, workflowType.orElse(null), failure);
+    }
+  }
+
   @Override
   public Optional<WorkflowOptions> getOptions() {
     return Optional.ofNullable(options);

temporal-sdk/src/main/java/io/temporal/common/interceptors/WorkflowClientCallsInterceptor.java

@@ -94,6 +94,8 @@ public interface WorkflowClientCallsInterceptor {
 
   TerminateOutput terminate(TerminateInput input);
 
+  DescribeWorkflowOutput describe(DescribeWorkflowInput input);
+
   final class WorkflowStartInput {
     private final String workflowId;
     private final String workflowType;
@@ -601,4 +603,28 @@ public Object[] getDetails() {
   }
 
   final class TerminateOutput {}
+
+  final class DescribeWorkflowInput {
+    private final WorkflowExecution workflowExecution;
+
+    public DescribeWorkflowInput(WorkflowExecution workflowExecution) {
+      this.workflowExecution = workflowExecution;
+    }
+
+    public WorkflowExecution getWorkflowExecution() {
+      return workflowExecution;
+    }
+  }
+
+  final class DescribeWorkflowOutput {
+    private final WorkflowExecutionDescription description;
+
+    public DescribeWorkflowOutput(WorkflowExecutionDescription description) {
+      this.description = description;
+    }
+
+    public WorkflowExecutionDescription getDescription() {
+      return description;
+    }
+  }
 }

temporal-sdk/src/main/java/io/temporal/common/interceptors/WorkflowClientCallsInterceptorBase.java

@@ -87,4 +87,9 @@ public CancelOutput cancel(CancelInput input) {
   public TerminateOutput terminate(TerminateInput input) {
     return next.terminate(input);
   }
+
+  @Override
+  public DescribeWorkflowOutput describe(DescribeWorkflowInput input) {
+    return next.describe(input);
+  }
 }

temporal-sdk/src/main/java/io/temporal/internal/client/RootWorkflowClientInvoker.java

@@ -693,6 +693,26 @@ public TerminateOutput terminate(TerminateInput input) {
     return new TerminateOutput();
   }
 
+  @Override
+  public DescribeWorkflowOutput describe(DescribeWorkflowInput input) {
+    DescribeWorkflowExecutionResponse response =
+        genericClient.describeWorkflowExecution(
+            DescribeWorkflowExecutionRequest.newBuilder()
+                .setNamespace(clientOptions.getNamespace())
+                .setExecution(input.getWorkflowExecution())
+                .build());
+
+    DataConverter dataConverterWithWorkflowContext =
+        clientOptions
+            .getDataConverter()
+            .withContext(
+                new WorkflowSerializationContext(
+                    clientOptions.getNamespace(), input.getWorkflowExecution().getWorkflowId()));
+
+    return new DescribeWorkflowOutput(
+        new WorkflowExecutionDescription(response, dataConverterWithWorkflowContext));
+  }
+
   private static <R> R convertResultPayloads(
       Optional<Payloads> resultValue,
       Class<R> resultClass,

temporal-sdk/src/main/java/io/temporal/internal/client/external/GenericWorkflowClient.java

@@ -78,6 +78,9 @@ CompletableFuture<ListWorkflowExecutionsResponse> listWorkflowExecutionsAsync(
 
   DescribeScheduleResponse describeSchedule(DescribeScheduleRequest request);
 
+  DescribeWorkflowExecutionResponse describeWorkflowExecution(
+      DescribeWorkflowExecutionRequest request);
+
   @Experimental
   UpdateWorkerBuildIdCompatibilityResponse updateWorkerBuildIdCompatability(
       UpdateWorkerBuildIdCompatibilityRequest request);

temporal-sdk/src/main/java/io/temporal/internal/client/external/GenericWorkflowClientImpl.java

@@ -303,6 +303,18 @@ public DescribeScheduleResponse describeSchedule(DescribeScheduleRequest request
         grpcRetryerOptions);
   }
 
+  @Override
+  public DescribeWorkflowExecutionResponse describeWorkflowExecution(
+      DescribeWorkflowExecutionRequest request) {
+    return grpcRetryer.retryWithResult(
+        () ->
+            service
+                .blockingStub()
+                .withOption(METRICS_TAGS_CALL_OPTIONS_KEY, metricsScope)
+                .describeWorkflowExecution(request),
+        grpcRetryerOptions);
+  }
+
   private static <T> CompletableFuture<T> toCompletableFuture(
       ListenableFuture<T> listenableFuture) {
     CompletableFuture<T> result = new CompletableFuture<>();

temporal-sdk/src/test/java/io/temporal/workflow/WorkflowDescribe.java

@@ -0,0 +1,56 @@
+/*
+ * Copyright (C) 2022 Temporal Technologies, Inc. All Rights Reserved.
+ *
+ * Copyright (C) 2012-2016 Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ *
+ * Modifications copyright (C) 2017 Uber Technologies, Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this material except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package io.temporal.workflow;
+
+import static org.junit.Assert.assertEquals;
+
+import io.temporal.client.WorkflowExecutionDescription;
+import io.temporal.client.WorkflowStub;
+import io.temporal.testing.internal.SDKTestWorkflowRule;
+import io.temporal.workflow.shared.TestWorkflows.TestWorkflow1;
+import org.junit.Rule;
+import org.junit.Test;
+
+public class WorkflowDescribe {
+
+  @Rule
+  public SDKTestWorkflowRule testWorkflowRule =
+      SDKTestWorkflowRule.newBuilder().setWorkflowTypes(TestInitWorkflow.class).build();
+
+  @Test
+  public void testWorkflowDescribe() {
+    TestWorkflow1 workflowStub =
+        testWorkflowRule.newWorkflowStubTimeoutOptions(TestWorkflow1.class);
+    String result = workflowStub.execute(testWorkflowRule.getTaskQueue());
+    assertEquals(testWorkflowRule.getTaskQueue(), result);
+    WorkflowExecutionDescription description = WorkflowStub.fromTyped(workflowStub).describe();
+    assertEquals(testWorkflowRule.getTaskQueue(), description.getTaskQueue());
+    assertEquals("TestWorkflow1", description.getWorkflowType());
+    assertEquals(WorkflowStub.fromTyped(workflowStub).getExecution(), description.getExecution());
+  }
+
+  public static class TestInitWorkflow implements TestWorkflow1 {
+    @Override
+    public String execute(String taskQueue) {
+      return taskQueue;
+    }
+  }
+}

temporal-test-server/src/main/java/io/temporal/internal/testservice/TestWorkflowMutableStateImpl.java

@@ -3024,7 +3024,8 @@ private DescribeWorkflowExecutionResponse describeWorkflowExecutionInsideLock()
         // No setAutoResetPoints - the test environment doesn't support that feature
         .setSearchAttributes(visibilityStore.getSearchAttributesForExecution(executionId))
         .setStatus(this.getWorkflowExecutionStatus())
-        .setHistoryLength(fullHistory.size());
+        .setHistoryLength(fullHistory.size())
+        .setTaskQueue(this.getStartRequest().getTaskQueue().getName());
 
     populateWorkflowExecutionInfoFromHistory(executionInfo, fullHistory);
 

temporal-testing/src/main/java/io/temporal/testing/TimeLockingInterceptor.java

@@ -193,6 +193,11 @@ public WorkflowStub newInstance(WorkflowOptions options) {
       return new TimeLockingWorkflowStub(locker, next.newInstance(options));
     }
 
+    @Override
+    public WorkflowExecutionDescription describe() {
+      return next.describe();
+    }
+
     /** Unlocks time skipping before blocking calls and locks back after completion. */
     private class TimeLockingFuture<R> extends CompletableFuture<R> {