How to make an API call
We’ve defined API calls and looked at how API calls work. Next, we’ll discuss making API calls so you can create a system that works for you.
There are several steps to building an API call. An API is created by an API provider, which can be an individual or a program.
There are different kinds of web APIs, but we will focus on REST API calls, also known as HTTP-based API calls. REST APIs follow a set of HTTP methods, which tells the API what to do.
Identify the API endpoint
The first step in making an API call is to identify the API endpoint. API endpoints tell the API call where to send your request so it can retrieve the information you want.
In other words, you are telling the API to go to a specific location on the web to get data. For example, if you wanted to use an API call to get data about public tweets, you would use the Twitter API endpoint in the API call.
Choose the right HTTP method
After identifying the endpoint, you must choose the correct HTTP method, sometimes called an HTTP verb. The HTTP method tells your API call what action you want it to take.
There are a number of HTTP verbs, but the four most common are:
- GET: Use this verb when you want to receive and collect information.
- POST: Use the POST verb when your goal is to generate a new resource.
- PUT: This HTTP verb edits or updates a resource via an API call.
- DELETE: Lastly, this verb deletes an unwanted resource or information.
Now that you’ve determined the HTTP method, it’s time to set up your header. The header acts as a roadmap to your API call; it determines what type of information to send back.
The three most common headers are user-agent, content-type, and accept. Let’s look at an example of each:
- User-agent header: This header identifies who is making the request. An example of a user agent is an application, operating system, or vendor.
- Content-type header: API calls use a content-type title to determine the type of content in the request. Without this header, the API will not be able to understand how to identify the information and will fail to send back a response.
- Accept header: The accept header explains how you would like to receive the information back from the calls, such as sending API calls back in JSON or XML format. In other words, it tells the API what format in which you will accept the data.
Add an API key
An API key acts as an authenticator for the API call. It essentially grants permission to the API request. An API key uses a sequence of letters and numbers to identify the client. Based on this sequence, the API call will be approved or denied.
There are two types of API keys: a public API key and a private API key.
A public API key is like an access code that can be shared with collaborators and provides limited data from your programs. A private API key should not be shared, as it will grant access to your entire database and development. Most API keys that allow information to be accessed from websites, such as social media, will be public API keys.
Send the request and wait for the response
Once you have all the pieces for the API call, it’s time to send the request. When you send the request, you’ll get a status code that lets you know if it was successful. If the request is unsuccessful, the code will indicate the issue so you can fix the problem and try again.
There are two types of codes you can receive: 2XX codes and 4XX codes.
The most common 2XX codes are:
- 200 OK: The API call fulfilled the request.
- 201 Created: The request was generated on the server.
- 202 Accepted: The request was accepted.
- 204 No Content: The request was successful, but no content was available to be returned.
Opposite of 2XX codes, 4XX codes are error codes:
- 400 Bad Request: There was an issue with the client’s request.
- 401 Unauthorized: The client is not authorized to request data. In this case, it usually means the client has incorrect or no credentials.
- 403 Forbidden: The request is correct, but the client cannot view the content.
- 404 Not Found: The information that was requested does not exist. For example, you may encounter a 404 code trying to get to a webpage that doesn’t exist.
Best practices for using API calls
You can use API calls to improve your business operations in many ways. Let’s review how you can create APIs that work for you:
- Choose the right API: First, decide what you want your API to do. That means figuring out what information you want the API to return.
- Document and test: It is vital to run API testing and ensure the API is reliable, functional, and secure. Testing your API calls includes making calls to different endpoints to see what returns the best results and documenting the response time and response codes.
- Implement security measures: Secure APIs are crucial. Ensure you have the appropriate security measures in place to ensure everyone’s information is protected. This is accomplished by providing API keys and making sure you verify API clients.
- Monitor results: You’ve tested your API calls, and everything works. Once you start using the API call, monitoring the process and ensuring the response is still accurate to provide a positive customer experience is essential.
Streamline your business operations with API calls
Adding multiple API calls to your business can help streamline operations in many ways. API calls can help collect valuable customer data, which will help your business develop more effective marketing tactics and materials. You can also use multiple APIs to streamline your internal business processes, freeing time for your employees and creating better workflows.
If you want to learn more about APIs and how you can leverage API calls to enhance your business operations, consider using Mailchimp.
With Mailchimp, you can access various resources and tools that help you improve your workflows. Whether you're interested in learning about API keys or integrations, Mailchimp has all the resources you need on one convenient platform.