Implemented HealthCheck feature

libraries/bot-builder/src/main/java/com/microsoft/bot/builder/ActivityHandler.java

@@ -10,9 +10,11 @@
 
 import org.apache.commons.lang3.StringUtils;
 
+import com.microsoft.bot.connector.ConnectorClient;
 import com.microsoft.bot.schema.Activity;
 import com.microsoft.bot.schema.ActivityTypes;
 import com.microsoft.bot.schema.ChannelAccount;
+import com.microsoft.bot.schema.HealthCheckResponse;
 import com.microsoft.bot.schema.MessageReaction;
 import com.microsoft.bot.schema.ResourceResponse;
 import com.microsoft.bot.schema.SignInConstants;
@@ -405,6 +407,10 @@ protected CompletableFuture<InvokeResponse> onInvokeActivity(TurnContext turnCon
                     }
                     return new InvokeResponse(HttpURLConnection.HTTP_INTERNAL_ERROR, null);
                 });
+        } else if (StringUtils.equals(turnContext.getActivity().getName(), "healthCheck")) {
+            CompletableFuture<InvokeResponse> result = new CompletableFuture<>();
+            result.complete(new InvokeResponse(HttpURLConnection.HTTP_OK, onHealthCheck(turnContext)));
+            return result;
         }
 
         CompletableFuture<InvokeResponse> result = new CompletableFuture<>();
@@ -436,6 +442,18 @@ protected CompletableFuture<Void> onSignInInvoke(TurnContext turnContext) {
         return result;
     }
 
+    /**
+     * Invoked when a 'healthCheck' event is
+     * received when the base behavior of onInvokeActivity is used.
+     *
+     * @param turnContext The current TurnContext.
+     * @return A task that represents a HealthCheckResponse.
+     */
+    protected CompletableFuture<HealthCheckResponse> onHealthCheck(TurnContext turnContext) {
+        ConnectorClient client = turnContext.getTurnState().get(BotFrameworkAdapter.CONNECTOR_CLIENT_KEY);
+        return CompletableFuture.completedFuture(HealthCheck.createHealthCheckResponse(client));
+    }
+
     /**
      * Creates a success InvokeResponse with the specified body.
      *

libraries/bot-builder/src/main/java/com/microsoft/bot/builder/HealthCheck.java

@@ -0,0 +1,51 @@
+// Copyright (c) Microsoft Corporation. All rights reserved.
+// Licensed under the MIT License.
+
+package com.microsoft.bot.builder;
+
+import java.util.concurrent.ExecutionException;
+
+import com.microsoft.bot.connector.ConnectorClient;
+import com.microsoft.bot.connector.authentication.AppCredentials;
+import com.microsoft.bot.schema.HealthCheckResponse;
+import com.microsoft.bot.schema.HealthResults;
+
+/**
+ * A class to process a HealthCheck request.
+ */
+public final class HealthCheck {
+
+    private HealthCheck() {
+        // not called
+    }
+
+    /**
+     * @param connector the ConnectorClient instance for this request
+     * @return HealthCheckResponse
+     */
+    public static HealthCheckResponse createHealthCheckResponse(ConnectorClient connector) {
+        HealthResults healthResults = new HealthResults();
+        healthResults.setSuccess(true);
+
+        if (connector != null) {
+            healthResults.setUserAgent(connector.getUserAgent());
+            AppCredentials credentials = (AppCredentials) connector.credentials();
+            try {
+                healthResults.setAuthorization(credentials.getToken().get());
+            } catch (InterruptedException | ExecutionException ignored) {
+                // An exception here may happen when you have a valid appId but invalid or blank secret.
+                // No callbacks will be possible, although the bot maybe healthy in other respects.
+            }
+        }
+
+        if (healthResults.getAuthorization() != null) {
+            healthResults.setMessages(new String[]{"Health check succeeded."});
+        } else {
+            healthResults.setMessages(new String[]{"Health check succeeded.", "Callbacks are not authorized."});
+        }
+
+        HealthCheckResponse response = new HealthCheckResponse();
+        response.setHealthResults(healthResults);
+        return response;
+    }
+}

libraries/bot-builder/src/test/java/com/microsoft/bot/builder/ActivityHandlerTests.java

@@ -7,6 +7,8 @@
 import java.util.ArrayList;
 import java.util.List;
 import java.util.concurrent.CompletableFuture;
+import java.util.concurrent.ExecutionException;
+import java.util.concurrent.atomic.AtomicReference;
 
 public class ActivityHandlerTests {
     @Test
@@ -346,6 +348,98 @@ public void TestUnrecognizedActivityType() {
         Assert.assertEquals("onUnrecognizedActivityType", bot.getRecord().get(0));
     }
 
+    @Test
+    public void TestHealthCheckAsyncOverride() {
+        Activity activity = new Activity() {
+            {
+                setType(ActivityTypes.INVOKE);
+                setName("healthCheck");
+            }
+        };
+
+        TurnContext turnContext = new TurnContextImpl(new TestInvokeAdapter(), activity);
+
+        TestActivityHandler bot = new TestActivityHandler();
+        bot.onTurn(turnContext).join();
+
+        Assert.assertEquals(2, bot.getRecord().size());
+        Assert.assertEquals("onInvokeActivity", bot.getRecord().get(0));
+        Assert.assertEquals("onHealthCheck", bot.getRecord().get(1));
+    }
+
+    @Test
+    public void TestHealthCheckAsync() {
+        Activity activity = new Activity() {
+            {
+                setType(ActivityTypes.INVOKE);
+                setName("healthCheck");
+            }
+        };
+
+        AtomicReference<List<Activity>> activitiesToSend = new AtomicReference<>();
+        TurnContext turnContext = new TurnContextImpl(new SimpleAdapter(activitiesToSend::set), activity);
+
+        ActivityHandler bot = new ActivityHandler();
+        bot.onTurn(turnContext).join();
+
+        Assert.assertNotNull(activitiesToSend.get());
+        Assert.assertEquals(1, activitiesToSend.get().size());
+        Assert.assertTrue(activitiesToSend.get().get(0).getValue() instanceof InvokeResponse);
+        Assert.assertEquals(200, ((InvokeResponse) activitiesToSend.get().get(0).getValue()).getStatus());
+        CompletableFuture future = ((CompletableFuture) ((InvokeResponse) activitiesToSend.get().get(0).getValue())
+                .getBody());
+        HealthCheckResponse result = new HealthCheckResponse();
+        result = (HealthCheckResponse) future.join();
+        Assert.assertTrue(result.getHealthResults().getSuccess());
+        String[] messages = result.getHealthResults().getMessages();
+        Assert.assertEquals(messages[0], "Health check succeeded.");
+    }
+
+    @Test
+    public void TestHealthCheckWithConnectorAsync() {
+        Activity activity = new Activity() {
+            {
+                setType(ActivityTypes.INVOKE);
+                setName("healthCheck");
+            }
+        };
+
+        AtomicReference<List<Activity>> activitiesToSend = new AtomicReference<>();
+        TurnContext turnContext = new TurnContextImpl(new SimpleAdapter(activitiesToSend::set), activity);
+        MockConnectorClient mockConnector = new MockConnectorClient("Windows/3.1", new MockAppCredentials("awesome"));
+        turnContext.getTurnState().add(BotFrameworkAdapter.CONNECTOR_CLIENT_KEY, mockConnector);
+        ActivityHandler bot = new ActivityHandler();
+        bot.onTurn(turnContext).join();
+
+        Assert.assertNotNull(activitiesToSend.get());
+        Assert.assertEquals(1, activitiesToSend.get().size());
+        Assert.assertTrue(activitiesToSend.get().get(0).getValue() instanceof InvokeResponse);
+        Assert.assertEquals(
+            200,
+            ((InvokeResponse) activitiesToSend.get().get(0).getValue()).getStatus()
+        );
+        CompletableFuture<HealthCheckResponse> future =
+            ((CompletableFuture<HealthCheckResponse>)
+            ((InvokeResponse) activitiesToSend.get().get(0).getValue()).getBody());
+        HealthCheckResponse result = new HealthCheckResponse();
+        result = (HealthCheckResponse) future.join();
+        Assert.assertTrue(result.getHealthResults().getSuccess());
+        Assert.assertEquals(result.getHealthResults().getAuthorization(), "awesome");
+        Assert.assertEquals(result.getHealthResults().getUserAgent(), "Windows/3.1");
+        String[] messages = result.getHealthResults().getMessages();
+        Assert.assertEquals(messages[0], "Health check succeeded.");
+    }
+
+    private static class TestInvokeAdapter extends NotImplementedAdapter {
+        @Override
+        public CompletableFuture<ResourceResponse[]> sendActivities(
+            TurnContext context,
+            List<Activity> activities
+        ) {
+            return CompletableFuture.completedFuture(new ResourceResponse[0]);
+        }
+    }
+
     private static class NotImplementedAdapter extends BotAdapter {
         @Override
         public CompletableFuture<ResourceResponse[]> sendActivities(
@@ -455,6 +549,18 @@ protected CompletableFuture onEvent(TurnContext turnContext) {
             return super.onEvent(turnContext);
         }
 
+        @Override
+        protected CompletableFuture<InvokeResponse> onInvokeActivity(TurnContext turnContext) {
+            record.add("onInvokeActivity");
+            return super.onInvokeActivity(turnContext);
+        }
+
+        @Override
+        protected CompletableFuture<HealthCheckResponse> onHealthCheck(TurnContext turnContext) {
+            record.add("onHealthCheck");
+            return super.onHealthCheck(turnContext);
+        }
+
         @Override
         protected CompletableFuture onInstallationUpdate(TurnContext turnContext) {
             record.add("onInstallationUpdate");

libraries/bot-builder/src/test/java/com/microsoft/bot/builder/MockAppCredentials.java

@@ -0,0 +1,36 @@
+package com.microsoft.bot.builder;
+
+import java.util.concurrent.CompletableFuture;
+
+import com.microsoft.bot.connector.authentication.AppCredentials;
+import com.microsoft.bot.connector.authentication.Authenticator;
+
+public class MockAppCredentials extends AppCredentials {
+
+    private String token;
+
+    public MockAppCredentials(String token) {
+        super(null);
+        this.token = token;
+    }
+
+    @Override
+    public CompletableFuture<String> getToken() {
+        CompletableFuture<String> result;
+
+        result = new CompletableFuture<String>();
+        result.complete(this.token);
+        return result;
+    }
+
+        /**
+     * Returns an appropriate Authenticator that is provided by a subclass.
+     *
+     * @return An Authenticator object.
+     * @throws MalformedURLException If the endpoint isn't valid.
+     */
+    protected Authenticator buildAuthenticator(){
+        return null;
+    };
+
+}

libraries/bot-builder/src/test/java/com/microsoft/bot/builder/MockConnectorClient.java

@@ -0,0 +1,86 @@
+package com.microsoft.bot.builder;
+
+import com.microsoft.bot.connector.Attachments;
+import com.microsoft.bot.connector.ConnectorClient;
+import com.microsoft.bot.connector.Conversations;
+import com.microsoft.bot.connector.authentication.AppCredentials;
+import com.microsoft.bot.rest.RestClient;
+import com.microsoft.bot.rest.credentials.ServiceClientCredentials;
+
+public class MockConnectorClient implements ConnectorClient {
+
+    private AppCredentials credentials;
+    private String userAgent;
+
+    public MockConnectorClient(String userAgent, AppCredentials credentials) {
+        this.userAgent = userAgent;
+        this.credentials = credentials;
+    }
+
+    private MemoryConversations conversations = new MemoryConversations();
+
+    @Override
+    public RestClient getRestClient() {
+        return null;
+    }
+
+    @Override
+    public String baseUrl() {
+        return null;
+    }
+
+    @Override
+    public ServiceClientCredentials credentials() {
+        return credentials;
+    }
+
+    @Override
+    public String getUserAgent() {
+        return userAgent;
+    }
+
+    @Override
+    public String getAcceptLanguage() {
+        return null;
+    }
+
+    @Override
+    public void setAcceptLanguage(String acceptLanguage) {
+
+    }
+
+    @Override
+    public int getLongRunningOperationRetryTimeout() {
+        return 0;
+    }
+
+    @Override
+    public void setLongRunningOperationRetryTimeout(int timeout) {
+
+    }
+
+    @Override
+    public boolean getGenerateClientRequestId() {
+        return false;
+    }
+
+    @Override
+    public void setGenerateClientRequestId(boolean generateClientRequestId) {
+
+    }
+
+    @Override
+    public Attachments getAttachments() {
+        return null;
+    }
+
+    @Override
+    public Conversations getConversations() {
+        return conversations;
+    }
+
+    @Override
+    public void close() throws Exception {
+
+    }
+}

libraries/bot-schema/src/main/java/com/microsoft/bot/schema/HealthCheckResponse.java

@@ -0,0 +1,40 @@
+// Copyright (c) Microsoft Corporation. All rights reserved.
+// Licensed under the MIT License.
+
+package com.microsoft.bot.schema;
+
+import com.fasterxml.jackson.annotation.JsonInclude;
+import com.fasterxml.jackson.annotation.JsonProperty;
+
+/**
+ * Defines the structure that is returned as the result of a health check on the bot.
+ * The health check is sent to the bot as an {@link Activity} of type "invoke" and this class along
+ * with {@link HealthResults} defines the structure of the body of the response.
+ * The name of the invoke Activity is "healthCheck".
+ */
+public class HealthCheckResponse {
+    /**
+     * The health check results.
+     */
+    @JsonProperty(value = "healthResults")
+    @JsonInclude(JsonInclude.Include.NON_EMPTY)
+    private HealthResults healthResults;
+
+    /**
+     * Gets the healthResults value.
+     *
+     * @return The healthResults value.
+     */
+    public HealthResults getHealthResults() {
+        return this.healthResults;
+    }
+
+    /**
+     * Sets the healthResults value.
+     *
+     * @param withHealthResults The healthResults value to set.
+     */
+    public void setHealthResults(HealthResults withHealthResults) {
+        this.healthResults = withHealthResults;
+    }
+}