feat: migrate and update api retry fns to use dynamic import of ES module pretry

Author: stern-shawn

serverless/examples/api-calls/retry-parallel/meta.json

@@ -0,0 +1,5 @@
+{
+    "title": "Configure retries for parallel API requests",
+    "type": "server"
+}
+  

serverless/examples/api-calls/retry-parallel/retry-parallel-function.js

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+const axios = require('axios');
+const qs = require('qs');
+
+// The root URL for an API which is known to fail on occasion
+const unstableSpaceUri = 'https://unstable-5604.twil.io';
+// We'll declare these functions outside of the handler since they have no
+// dependencies on other values, and this will tidy up our pRetry calls.
+const astronautRequest = () => axios.get(`${unstableSpaceUri}/astros`);
+const issRequest = () => axios.get(`${unstableSpaceUri}/iss`);
+// Use a common object for retry configuration to DRY up our code :)
+const retryConfig = (reqName) => ({
+  retries: 3,
+  onFailedAttempt: () => console.log(`Retrying ${reqName}...`),
+});
+
+exports.handler = async (context, event, callback) => {
+  // We need to asynchronously import p-retry since it is an ESM module
+  const { default: pRetry } = await import('p-retry');
+  // Create a new voice response object
+  const twiml = new Twilio.twiml.VoiceResponse();
+
+  try {
+    // Create a promise with retry for each API call that can be made
+    // independently of each other
+    const getAstronauts = pRetry(astronautRequest, retryConfig('astros'));
+    const getIss = pRetry(issRequest, retryConfig('iss'));
+    // pRetry returns a promise, so we can still use Promise.all to await
+    // the result of both requests in parallel with retry and backoff enabled!
+    const [astronauts, iss] = await Promise.all([getAstronauts, getIss]);
+
+    const { number, people } = astronauts.data;
+    const { latitude, longitude } = iss.data.iss_position;
+
+    const names = people.map((astronaut) => astronaut.name).sort();
+
+    // We can use reverse geocoding to convert the latitude and longitude
+    // of the ISS to a human-readable location. We'll use positionstack.com
+    // since they provide a free API.
+    // Be sure to set your positionstack API key as an environment variable!
+    const { data: issLocation } = await pRetry(
+      () =>
+        axios.get(
+          `http://api.positionstack.com/v1/reverse?${qs.stringify({
+            access_key: context.POSITIONSTACK_API_KEY,
+            query: `${latitude},${longitude}`,
+          })}`
+        ),
+      retryConfig('iss location')
+    );
+
+    const { label } = issLocation.data[0] || 'an unknown location';
+
+    // Create a list formatter to join the names with commas and 'and'
+    // so that the played speech sounds more natural
+    const listFormatter = new Intl.ListFormat('en');
+
+    twiml.say(`There are ${number} people in space.`);
+    twiml.pause({ length: 1 });
+    twiml.say(`Their names are: ${listFormatter.format(names)}`);
+    twiml.pause({ length: 1 });
+    twiml.say(
+      `Also, the International Space Station is currently above ${label}`
+    );
+    // Return the final TwiML as the second argument to `callback`
+    // This will render the response as XML in reply to the webhook request
+    // and result in the message being played back to the user
+    return callback(null, twiml);
+  } catch (error) {
+    // In the event of an error, return a 500 error and the error message
+    console.error(error);
+    return callback(error);
+  }
+};

serverless/examples/api-calls/retry/meta.json

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+{
+    "title": "Configure retries for an API request",
+    "type": "server"
+}
+  

serverless/examples/api-calls/retry/retry-function.js

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+const axios = require('axios');
+
+const getAstronauts = () => axios.get('https://unstable-5604.twil.io/astros');
+
+exports.handler = async (context, event, callback) => {
+  // We need to asynchronously import p-retry since it is an ESM module
+  const { default: pRetry } = await import('p-retry');
+  // Create a new voice response object
+  const twiml = new Twilio.twiml.VoiceResponse();
+
+  try {
+    let attempts = 1;
+    // Open APIs From Space: http://open-notify.org
+    // Number of people in space
+    const response = await pRetry(getAstronauts, {
+      retries: 3,
+      onFailedAttempt: ({ attemptNumber, retriesLeft }) => {
+        attempts = attemptNumber;
+        console.log(
+          `Attempt ${attemptNumber} failed. There are ${retriesLeft} retries left.`
+        );
+        // 1st request => "Attempt 1 failed. There are 3 retries left."
+        // 2nd request => "Attempt 2 failed. There are 2 retries left."
+        // …
+      },
+    });
+    const { number, people } = response.data;
+
+    const names = people.map((astronaut) => astronaut.name).sort();
+    // Create a list formatter to join the names with commas and 'and'
+    // so that the played speech sounds more natural
+    const listFormatter = new Intl.ListFormat('en');
+
+    twiml.say(`There are ${number} people in space.`);
+    twiml.pause({ length: 1 });
+    twiml.say(`Their names are: ${listFormatter.format(names)}`);
+    // If retries were necessary, add that information to the response
+    if (attempts > 1) {
+      twiml.pause({ length: 1 });
+      twiml.say(`It took ${attempts} attempts to retrieve this information.`);
+    }
+    // Return the final TwiML as the second argument to `callback`
+    // This will render the response as XML in reply to the webhook request
+    // and result in the message being played back to the user
+    return callback(null, twiml);
+  } catch (error) {
+    // In the event of an error, return a 500 error and the error message
+    console.error(error);
+    return callback(error);
+  }
+};