How to Develop Faster Using a Mock API Service

When it comes to software development, the speed of delivery is crucial as we want features to reach production as soon as possible. There are many ways to speed up the development of an application, and one of them is using a mock API service.

A mock API service allows us to simulate a real API because sometimes the real API is not ready, doesn't exist, has issues, or we cannot access it from the development environment. In such cases, we use a mock API service to continue developing.

Don't Wait for the Backend, Use a Mock Server

Front-end developers are often limited by the absence of a finished backend to use its API. This shouldn't be the case, as with a mock server, you can agree with backend developers on the approximate API response and path to start mocking it and begin development.

In other words, instead of waiting for the backend, you can start developing by pointing your front end to your mock API server. It's true that the backend response might change eventually, but it probably won't change so drastically that you'd have to start from scratch. Therefore, it’s crucial to reach an agreement between both teams on the path and body of the endpoint to be mocked with the mock API server.

This way, development time is accelerated as both teams can work in parallel on the same functionality.

Return as Many Errors as Needed from Your Mock Server

Another advantage of using a mock server is that we can simulate the errors we need because sometimes forcing errors with the real backend is complicated. For instance, we can return a 404 from our mock API server and see how the front end behaves. This aspect is very important as often only the happy path is developed, and we forget to handle errors.

With a mock API service, we can return as many errors as needed, even testing 500 errors and seeing how the front end handles them.

Mock Responses to Have Multiple Results

Sometimes our real backend doesn't have as many results as we would like, or if we want to have them, we have to create them manually, which becomes very tedious. Using a mock API service allows you to return as many results as needed and test various use cases or how the interface behaves when you have multiple results. You could even simulate pagination in a list of results from your mock API server.

This saves you from creating fictitious data for the backend to return, allowing you to dedicate that time to programming.

Add Different Latencies to Your Mock Server Responses

Sometimes, when developing against a backend from a local environment, the response is very fast, or even when hitting the development backend, we get very fast responses. However, we want to test what happens to the interface when a response is not so fast. Should we add a spinner? Should we show a loading message?

With a mock server, you can set latencies in the responses to take as long as needed, simulating this behavior in the interface and deciding whether to add a spinner or a loading message as appropriate.

Return Different Data Types from Your Mock Server

A common error during development is that the data we use for testing fits perfectly with our interface, and we don't realize until one day in production there is a very large number that breaks our interface or very long names that don't fit the design.

Testing this with a real backend can be a bit costly since you would need to create the data for the backend to return and then see how your interface behaves. However, with a mock API service, you can change the data as much as you want and test it in your front end instantly.

API Documentation Using Your Mock Server

Another advantage of using a mock server is that you can use it as documentation. That is, by mocking your endpoints, you can share them with others as they can see the path, HTTP method, status code, and body that is returned. This is very useful because if you keep your mock API updated, you can share it with other developers so they can even integrate with it.

Mocking Third-Party Services

Another complexity that arises and consumes a lot of development time is when integrating with third-party services. Sometimes, in development, we don't want to hit the real third-party service but would like something to simulate responses and see how our application behaves. For this, we can use a mock server to simulate the responses of these services without relying on them.

Conclusion

Using mock APIs is a great idea and very helpful for faster development as it allows us to use a mock server to return all kinds of responses, errors, latencies, etc.

If you haven't used a mock API service yet, we recommend you try it out and consider using Mockfly as it offers all these advantages and more.