samples: add sample code to query regional Dialogflow agent (#310)

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Fixes #<issue_number_goes_here> ☕️

dialogflow/snippets/src/main/java/com/example/dialogflow/DetectIntentWithLocation.java

@@ -0,0 +1,79 @@
+/*
+ * Copyright 2020 Google LLC
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file 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 com.example.dialogflow;
+
+// [START dialogflow_detect_intent_with_location]
+
+import com.google.api.gax.rpc.ApiException;
+import com.google.cloud.dialogflow.v2beta1.DetectIntentResponse;
+import com.google.cloud.dialogflow.v2beta1.QueryInput;
+import com.google.cloud.dialogflow.v2beta1.QueryResult;
+import com.google.cloud.dialogflow.v2beta1.SessionName;
+import com.google.cloud.dialogflow.v2beta1.SessionsClient;
+import com.google.cloud.dialogflow.v2beta1.SessionsSettings;
+import com.google.cloud.dialogflow.v2beta1.TextInput;
+import com.google.common.collect.Maps;
+import java.io.IOException;
+import java.util.List;
+import java.util.Map;
+
+public class DetectIntentWithLocation {
+
+  // DialogFlow API Detect Intent sample with text inputs.
+  public static Map<String, QueryResult> detectIntentWithLocation(
+      String projectId, String locationId, List<String> texts, String sessionId,
+      String languageCode)
+      throws IOException, ApiException {
+    SessionsSettings sessionsSettings = SessionsSettings.newBuilder()
+        .setEndpoint(locationId + "-dialogflow.googleapis.com:443").build();
+    Map<String, QueryResult> queryResults = Maps.newHashMap();
+    // Instantiates a client
+    try (SessionsClient sessionsClient = SessionsClient.create(sessionsSettings)) {
+      // Set the session name using the projectId (my-project-id), locationId and sessionId (UUID)
+      SessionName session = SessionName
+          .ofProjectLocationSessionName(projectId, locationId, sessionId);
+      System.out.println("Session Path: " + session.toString());
+
+      // Detect intents for each text input
+      for (String text : texts) {
+        // Set the text (hello) and language code (en-US) for the query
+        TextInput.Builder textInput =
+            TextInput.newBuilder().setText(text).setLanguageCode(languageCode);
+
+        // Build the query with the TextInput
+        QueryInput queryInput = QueryInput.newBuilder().setText(textInput).build();
+
+        // Performs the detect intent request
+        DetectIntentResponse response = sessionsClient.detectIntent(session, queryInput);
+
+        // Display the query result
+        QueryResult queryResult = response.getQueryResult();
+
+        System.out.println("====================");
+        System.out.format("Query Text: '%s'\n", queryResult.getQueryText());
+        System.out.format(
+            "Detected Intent: %s (confidence: %f)\n",
+            queryResult.getIntent().getDisplayName(), queryResult.getIntentDetectionConfidence());
+        System.out.format("Fulfillment Text: '%s'\n", queryResult.getFulfillmentText());
+
+        queryResults.put(text, queryResult);
+      }
+    }
+    return queryResults;
+  }
+}
+// [END dialogflow_detect_intent_with_location]

dialogflow/snippets/src/test/java/com/example/dialogflow/DetectIntentWithSentimentAndTextToSpeechIT.java

@@ -32,12 +32,15 @@
 import org.junit.runner.RunWith;
 import org.junit.runners.JUnit4;
 
-/** Integration (system) tests for {@link DetectIntentWithSentimentAnalysis}. */
+/**
+ * Integration (system) tests for {@link DetectIntentWithSentimentAnalysis}.
+ */
 @RunWith(JUnit4.class)
 @SuppressWarnings("checkstyle:abbreviationaswordinname")
 public class DetectIntentWithSentimentAndTextToSpeechIT {
 
   private static String PROJECT_ID = System.getenv().get("GOOGLE_CLOUD_PROJECT");
+  private static String LOCATION_ID = "asia-northeast1";
   private static String SESSION_ID = UUID.randomUUID().toString();
   private static String LANGUAGE_CODE = "en-US";
   private static List<String> TEXTS =
@@ -72,6 +75,17 @@ public void testDetectIntentTexts() throws Exception {
     assertEquals("All set!", finalResult.getFulfillmentText());
   }
 
+  @Test
+  public void testDetectIntentTextsWithLocation() throws Exception {
+    Map<String, com.google.cloud.dialogflow.v2beta1.QueryResult> queryResults =
+        DetectIntentWithLocation
+            .detectIntentWithLocation(PROJECT_ID, LOCATION_ID, TEXTS, SESSION_ID, LANGUAGE_CODE);
+    com.google.cloud.dialogflow.v2beta1.QueryResult finalResult =
+        queryResults.get(TEXTS.get(TEXTS.size() - 1));
+    assertTrue(finalResult.getAllRequiredParamsPresent());
+    assertEquals("All set!", finalResult.getFulfillmentText());
+  }
+
   @Test
   public void testDetectIntentWithSentimentAnalysis() throws Exception {
     assertResults(