Add pollingWaitTimeMs to UpdatableOptions (#436)

README.md

@@ -129,6 +129,8 @@ Returns the current polling state of the consumer: `true` if it is actively poll
 
 Updates the provided option with the provided value.
 
+Please note that any update of the option `pollingWaitTimeMs` will take effect only on next polling cycle.
+
 You can [find out more about this here](https://bbc.github.io/sqs-consumer/classes/Consumer.html#updateOption).
 
 ### Events

src/types.ts

@@ -124,7 +124,8 @@ export interface ConsumerOptions {
 export type UpdatableOptions =
   | 'visibilityTimeout'
   | 'batchSize'
-  | 'waitTimeSeconds';
+  | 'waitTimeSeconds'
+  | 'pollingWaitTimeMs';
 
 export interface StopOptions {
   /**

src/validation.ts

@@ -45,6 +45,11 @@ function validateOption(
         throw new Error('waitTimeSeconds must be between 0 and 20.');
       }
       break;
+    case 'pollingWaitTimeMs':
+      if (value < 0) {
+        throw new Error('pollingWaitTimeMs must be greater than 0.');
+      }
+      break;
     default:
       if (strict) {
         throw new Error(`The update ${option} cannot be updated`);

test/tests/consumer.test.ts

@@ -1551,6 +1551,34 @@ describe('Consumer', () => {
       sandbox.assert.notCalled(optionUpdatedListener);
     });
 
+    it('updates the pollingWaitTimeMs option and emits an event', () => {
+      const optionUpdatedListener = sandbox.stub();
+      consumer.on('option_updated', optionUpdatedListener);
+
+      consumer.updateOption('pollingWaitTimeMs', 1000);
+
+      assert.equal(consumer.pollingWaitTimeMs, 1000);
+
+      sandbox.assert.calledWithMatch(
+        optionUpdatedListener,
+        'pollingWaitTimeMs',
+        1000
+      );
+    });
+
+    it('does not update the pollingWaitTimeMs if the value is less than 0', () => {
+      const optionUpdatedListener = sandbox.stub();
+      consumer.on('option_updated', optionUpdatedListener);
+
+      assert.throws(() => {
+        consumer.updateOption('pollingWaitTimeMs', -1);
+      }, 'pollingWaitTimeMs must be greater than 0.');
+
+      assert.equal(consumer.pollingWaitTimeMs, 0);
+
+      sandbox.assert.notCalled(optionUpdatedListener);
+    });
+
     it('throws an error for an unknown option', () => {
       consumer = new Consumer({
         region: REGION,