Catch your errors

Published on Monday, 5 July 2021.
At 186 words, this article should take about 1 minute to read.

All too often I have seen (and written) code that looks like this…

  const response = await getSomeDataFromAnAPI();
  handleTheHappyPath(response)

Invariably, at some point, the API is down or the response is malformed or my internet connection drops off or some other reason I haven't thought of and my handleTheHappyPath() function simply doesn't work.

Troubleshooting errors is tricky at the best of times but it's even harder if your code is not set up to handle errors.

Here are a few different ways to handle failures. Which one you should use will depend on a variety of things such as the existing codebase, when you want to handle the failure, or what you need to do in your handleTheHappyPath function.

Try/Catch

try {
  const response = await getSomeDataFromAnAPI();

  if (!response.ok || response.statusCode > 299) {
    throw new Error(response.statusText);
  }
  handleTheHappyPath(response)
} catch(error) {
  console.error('🚫  Oh noes!', error);
}

Then

  getSomeDataFromAnAPI()
  .then(response => {
    if (!response.ok || response.statusCode > 299) {
      throw new Error(response.statusText);
    }
    handleTheHappyPath(response)
  })
  .catch(error => {
    console.error('🚫  Oh noes!', error);
  })

Await

  const response = await getSomeDataFromAnAPI();
  handleTheHappyPath(response)

  response().catch((error) => {
    console.error('🚫  Oh noes!', error);
  })

Fin

Cover image courtesy of Diana Polekhina.

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