"APIs 101"

If you're completely new to APIs, this webinar is for you. In this session, Developer Educator Sue Smith talks about API basics with a practical walkthrough inside the Postman app. Agenda includes:

  • Intro to APIs
  • The basic components of an API request
  • Building and sending API requests
  • Understanding API responses
  • Further learning in Postman
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Aired: Thursday, August 6, 2020

Postman Version: 7.30.1

Sue Smith. Developer Educator at Postman.

Sue Smith

Developer Educator

Postman for Enterprises

Develop APIs for the enterprise with the broad capabilities of the Postman API Platform.

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What exactly is a REST API?

A REST (representational state transfer) API is an interface for accessing and manipulating data. Client apps, such as websites and mobile apps, make requests to REST APIs to carry out data operations. Some examples of data operations are retrieving, adding, and updating data.

How do I add a URL variable?

You can add a URL as a variable at the collection or environment level in Postman. Here's how: Add the variable, set the URL as its value, and then reference it in your requests using double curly braces. Check out these Postman documentation pages for details:

Adding environment variables

Using variables

Is it possible to automate requests or do I have to do that manually?

You can automate running requests in Postman using the Collection Runner. Check out our page on reusing the Collection Runner.

How can I integrate Postman Collections in my code repository?

You can integrate your Postman Collection with GitHub and GitLab. Check out these Postman documentation pages for details:

GitHub integration

Gitlab integration

How can I send a request via a script or browser?

You can send some API requests just by entering the URL into your browser address bar. You can also use Postman on the Web (currently in beta).

If you want to control the execution of requests using scripts in Postman, you can do that by using the Collection Runner.

Is there a way to auto-format the JSON body that I created in Postman?

Yes. You can beautify JSON in Postman using the button at the top right of the body editor area. Your JSON response data should be automatically formatted if the request headers are correctly configured; however, you can also choose JSON from the drop-down list in the response body display.

Does Postman Visualizer only work in light mode? I have my settings in dark mode, and the text remains black on the dark background.

Postman Visualizer should work on both dark and light mode, but you may need to add some styling to render the background dark and the text white. Switching to the light theme first might help.

How can I know the throughput of any API (i.e., what can be highest data packet size while data fetching)?

Postman does not impose a hard limit on response size and can receive up to 100MB size without any issues. Regarding the limit defined by the API itself, that information is specified by the provider in their documentation.

Why do I need to create collections?

You don't need to create Postman Collections, but they often come in handy and help you simplify certain activities. You can use collections to organize your requests and to group them for testing. Collections also provide access to additional Postman utilities such as auto-generated documentation, automation via the Collection Runner, mock data, monitoring, and more.

Can I have the same authorization for the whole collection?

Yes, you can set it up at the collection level, then select "Inherit auth from parent" in each request.

How is the response data stored on the server side?

There's a number of different ways that APIs handle data storage. This demo API from the “APIs 101” webinar uses a lightweight database called lowdb, but you will find many different data modeling and storage setups in different APIs. Some store encrypted data using an encryption algorithm, while others store it as a simple text.

Can I export data from Postman?

Yes. You can export your collections in the Postman Collection format (JSON). Learn more about importing and exporting data with Postman.

Is there any way to automate actions even if they need integration with another app?

Yes. Postman allows you to integrate with many popular applications. You can use Newman, which is a command-line collection runner for Postman. Newman is built with extensibility in mind so that you can easily integrate it with your continuous integration servers and build systems.
You can also use Postman integrations, which allow you to automate sharing data and functionality between Postman and other tools you might be using for your API development. Available integrations include Slack, GitHub, Datadog, OpenAPI, Microsoft Teams, and more.

How can I create documentation for my APIs to help people learn how to use them?

If you're building an API for public use, you can generate docs automatically from Postman. We have a step-by-step tutorial for documenting your API which encourage you to check out.

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