sample: add samples for dead letter topics (#1010)

* feat: added docs for DQL samples * feat: samples for DLQ * test:added test cases for dql * fix: lint issue * fix: review changes Co-authored-by: Megan Potter <[email protected]>
googleapis · Jun 1, 2020 · 85f17a1 · 85f17a1
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diff --git a/samples/createSubscriptionWithDeadLetterPolicy.js b/samples/createSubscriptionWithDeadLetterPolicy.js
@@ -0,0 +1,69 @@
+// 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.
+
+/**
+ * This application demonstrates how to perform basic operations on
+ * subscriptions with the Google Cloud Pub/Sub API.
+ *
+ * For more information, see the README.md under /pubsub and the documentation
+ * at https://cloud.google.com/pubsub/docs.
+ */
+
+'use strict';
+
+// sample-metadata:
+//   title: Create Subscription With Dead Letter Policy
+//   description: Creates a new subscription With Dead Letter Policy.
+//   usage: node createSubscriptionWithDeadLetterPolicy.js <topic-name> <subscription-name> <dead-letter-topic-name>
+
+function main(
+  topicName = 'YOUR_TOPIC_NAME',
+  subscriptionName = 'YOUR_SUBSCRIPTION_NAME',
+  deadLetterTopicName = 'YOUR_DEAD_LETTER_TOPIC_NAME'
+) {
+  // [START pubsub_dead_letter_create_subscription]
+  /**
+   * TODO(developer): Uncomment these variables before running the sample.
+   */
+  // const topicName = 'YOUR_TOPIC_NAME';
+  // const subscriptionName = 'YOUR_SUBSCRIPTION_NAME';
+  // const deadLetterTopicName = 'YOUR_DEAD_LETTER_TOPIC_NAME';
+
+  // Imports the Google Cloud client library
+  const {PubSub} = require('@google-cloud/pubsub');
+
+  // Creates a client; cache this for further use
+  const pubSubClient = new PubSub();
+
+  async function createSubscriptionWithDeadLetterPolicy() {
+    // Creates a new subscription
+    await pubSubClient.topic(topicName).createSubscription(subscriptionName, {
+      deadLetterPolicy: {
+        deadLetterTopic: pubSubClient.topic(deadLetterTopicName).name,
+        maxDeliveryAttempts: 10,
+      },
+    });
+    console.log(
+      `Created subscription ${subscriptionName} with dead letter topic ${deadLetterTopicName}.`
+    );
+    console.log(
+      'To process dead letter messages, remember to add a subscription to your dead letter topic.'
+    );
+  }
+
+  createSubscriptionWithDeadLetterPolicy().catch(console.error);
+  // [END pubsub_dead_letter_create_subscription]
+}
+
+main(...process.argv.slice(2));
diff --git a/samples/removeDeadLetterPolicy.js b/samples/removeDeadLetterPolicy.js
@@ -0,0 +1,66 @@
+// 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.
+
+/**
+ * This application demonstrates how to perform basic operations on
+ * subscriptions with the Google Cloud Pub/Sub API.
+ *
+ * For more information, see the README.md under /pubsub and the documentation
+ * at https://cloud.google.com/pubsub/docs.
+ */
+
+'use strict';
+
+// sample-metadata:
+//   title: Remove Dead Letter Policy
+//   description: Remove Dead Letter Policy from subscription.
+//   usage: node removeDeadLetterPolicy.js <topic-name> <subscription-name>
+
+function main(
+  topicName = 'YOUR_TOPIC_NAME',
+  subscriptionName = 'YOUR_SUBSCRIPTION_NAME'
+) {
+  // [START pubsub_dead_letter_remove]
+  /**
+   * TODO(developer): Uncomment these variables before running the sample.
+   */
+  // const topicName = 'YOUR_TOPIC_NAME';
+  // const subscriptionName = 'YOUR_SUBSCRIPTION_NAME';
+
+  // Imports the Google Cloud client library
+  const {PubSub} = require('@google-cloud/pubsub');
+
+  // Creates a client; cache this for further use
+  const pubSubClient = new PubSub();
+
+  async function removeDeadLetterPolicy() {
+    const metadata = {
+      deadLetterPolicy: null,
+    };
+
+    await pubSubClient
+      .topic(topicName)
+      .subscription(subscriptionName)
+      .setMetadata(metadata);
+
+    console.log(
+      `Removed dead letter topic from ${subscriptionName} subscription.`
+    );
+  }
+
+  removeDeadLetterPolicy().catch(console.error);
+  // [END pubsub_dead_letter_remove]
+}
+
+main(...process.argv.slice(2));
diff --git a/samples/synchronousPullWithDeliveryAttempts.js b/samples/synchronousPullWithDeliveryAttempts.js
@@ -0,0 +1,87 @@
+// 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.
+
+/**
+ * This application demonstrates how to perform basic operations on
+ * subscriptions with the Google Cloud Pub/Sub API.
+ *
+ * For more information, see the README.md under /pubsub and the documentation
+ * at https://cloud.google.com/pubsub/docs.
+ */
+
+'use strict';
+
+// sample-metadata:
+//   title: Synchronous Pull with delivery attempt.
+//   description: Receive messages synchronously with delivery attempt.
+//   usage: node synchronousPullWithDeliveryAttempts.js <project-id> <subscription-name>
+
+function main(
+  projectId = 'YOUR_PROJECT_ID',
+  subscriptionName = 'YOUR_SUBSCRIPTION_NAME'
+) {
+  // [START pubsub_dead_letter_delivery_attempt]
+  /**
+   * TODO(developer): Uncomment these variables before running the sample.
+   */
+  // const projectId = 'YOUR_PROJECT_ID';
+  // const subscriptionName = 'YOUR_SUBSCRIPTION_NAME';
+
+  // Imports the Google Cloud client library. v1 is for the lower level
+  // proto access.
+  const {v1} = require('@google-cloud/pubsub');
+
+  // Creates a client; cache this for further use.
+  const subClient = new v1.SubscriberClient();
+
+  async function synchronousPullWithDeliveryAttempts() {
+    const formattedSubscription = subClient.subscriptionPath(
+      projectId,
+      subscriptionName
+    );
+
+    // The maximum number of messages returned for this request.
+    // Pub/Sub may return fewer than the number specified.
+    const request = {
+      subscription: formattedSubscription,
+      maxMessages: 10,
+    };
+
+    // The subscriber pulls a specified number of messages.
+    const [response] = await subClient.pull(request);
+
+    // Process the messages.
+    const ackIds = [];
+    for (const message of response.receivedMessages) {
+      console.log(`Received message: ${message.message.data}`);
+      console.log(`Delivery Attempt: ${message.deliveryAttempt}`);
+      ackIds.push(message.ackId);
+    }
+
+    // Acknowledge all of the messages. You could also ackknowledge
+    // these individually, but this is more efficient.
+    const ackRequest = {
+      subscription: formattedSubscription,
+      ackIds: ackIds,
+    };
+    await subClient.acknowledge(ackRequest);
+
+    console.log('Done.');
+  }
+
+  synchronousPullWithDeliveryAttempts().catch(console.error);
+  // [END pubsub_dead_letter_delivery_attempt]
+}
+
+main(...process.argv.slice(2));
diff --git a/samples/system-test/subscriptions.test.js b/samples/system-test/subscriptions.test.js
@@ -28,10 +28,14 @@ describe('subscriptions', () => {
   const runId = uuid.v4();
   const topicNameOne = `topic1-${runId}`;
   const topicNameTwo = `topic2-${runId}`;
+  const topicNameThree = `topic3-${runId}`;
   const subscriptionNameOne = `sub1-${runId}`;
   const subscriptionNameTwo = `sub2-${runId}`;
   const subscriptionNameThree = `sub3-${runId}`;
   const subscriptionNameFour = `sub4-${runId}`;
+  const subscriptionNameFive = `sub5-${runId}`;
+  const subscriptionNameSix = `sub6-${runId}`;
+  const subscriptionNameSeven = `sub7-${runId}`;
   const fullTopicNameOne = `projects/${projectId}/topics/${topicNameOne}`;
   const fullSubscriptionNameOne = `projects/${projectId}/subscriptions/${subscriptionNameOne}`;
   const fullSubscriptionNameTwo = `projects/${projectId}/subscriptions/${subscriptionNameTwo}`;
@@ -45,6 +49,7 @@ describe('subscriptions', () => {
     return Promise.all([
       pubsub.createTopic(topicNameOne),
       pubsub.createTopic(topicNameTwo),
+      pubsub.createTopic(topicNameThree),
     ]);
   });
 
@@ -285,4 +290,93 @@ describe('subscriptions', () => {
     assert.ok(subscriptions);
     assert(subscriptions.every(s => s.name !== fullSubscriptionNameOne));
   });
+
+  it('should create a subscription with dead letter policy.', async () => {
+    const output = execSync(
+      `${commandFor(
+        'createSubscriptionWithDeadLetterPolicy'
+      )} ${topicNameTwo} ${subscriptionNameFive} ${topicNameThree}`
+    );
+    assert.include(
+      output,
+      `Created subscription ${subscriptionNameFive} with dead letter topic ${topicNameThree}.`
+    );
+    const [subscription] = await pubsub
+      .topic(topicNameTwo)
+      .subscription(subscriptionNameFive)
+      .get();
+    assert.strictEqual(
+      subscription.metadata.deadLetterPolicy.maxDeliveryAttempts,
+      10
+    );
+  });
+
+  it('should listen for messages synchronously with delivery attempts.', async () => {
+    await pubsub.topic(topicNameOne).createSubscription(subscriptionNameSix, {
+      deadLetterPolicy: {
+        deadLetterTopic: pubsub.topic(topicNameThree).name,
+        maxDeliveryAttempts: 10,
+      },
+    });
+
+    await pubsub.topic(topicNameOne).publish(Buffer.from('Hello, world!'));
+    const output = execSync(
+      `${commandFor(
+        'synchronousPullWithDeliveryAttempts'
+      )} ${projectId} ${subscriptionNameSix}`
+    );
+    assert.match(output, /Hello/);
+    assert.match(output, /Delivery Attempt: 1/);
+  });
+
+  it('should update a subscription with dead lettter policy.', async () => {
+    await pubsub
+      .topic(topicNameOne)
+      .subscription(subscriptionNameSeven, {
+        deadLetterPolicy: {
+          deadLetterTopic: pubsub.topic(topicNameThree).name,
+          maxDeliveryAttempts: 10,
+        },
+      })
+      .get({autoCreate: true});
+
+    execSync(
+      `${commandFor(
+        'updateDeadLetterPolicy'
+      )} ${topicNameOne} ${subscriptionNameSeven}`
+    );
+
+    const [subscription] = await pubsub
+      .topic(topicNameOne)
+      .subscription(subscriptionNameSeven)
+      .get();
+    assert.equal(
+      subscription.metadata.deadLetterPolicy.maxDeliveryAttempts,
+      15
+    );
+  });
+
+  it('should remove dead lettter policy.', async () => {
+    await pubsub
+      .topic(topicNameOne)
+      .subscription(subscriptionNameSeven, {
+        deadLetterPolicy: {
+          deadLetterTopic: pubsub.topic(topicNameThree).name,
+          maxDeliveryAttempts: 10,
+        },
+      })
+      .get({autoCreate: true});
+
+    execSync(
+      `${commandFor(
+        'removeDeadLetterPolicy'
+      )} ${topicNameOne} ${subscriptionNameSeven}`
+    );
+
+    const [subscription] = await pubsub
+      .topic(topicNameOne)
+      .subscription(subscriptionNameSeven)
+      .get();
+    assert.isNull(subscription.metadata.deadLetterPolicy);
+  });
 });