Postman Quick Guide

1. API Client — What and Why?

An API client is a tool used to communicate with an API.

Instead of manually running:

curl -X GET "https://example.com/api/v1/users" \
  -H "Authorization: Bearer TOKEN"

You can configure the same request visually in Postman:

• HTTP method: GET
• URL: https://example.com/api/users
• Headers: Authorization: Bearer TOKEN
• Body: JSON, form data, etc.

Postman then sends the request and displays:

• HTTP status code
• Response body
• Response headers
• Response time
• Response size

Alternatives

• Bruno
• Insomnia
• cURL
• HTTPie
• Hoppscotch
• Yaak
• Advanced REST Client (ARC)
• RapidAPI Client
• JetBrains HTTP Client
• VS Code REST Client
• Thunder Client
• SoapUI

2. Export to cURL / Import from cURL

Postman can convert requests between its graphical interface and curl.

Export a Request to cURL

Open the request you want to export.

Click:

Code → cURL

Postman generates an equivalent command, for example:

curl --location 'https://dev.ticket.solidservice.link/api/v1/metadata/entities'

Import a cURL Command

You can also go in the opposite direction.

Click:

Import → Raw text

Paste your cURL command:

curl --location 'https://dev.ticket.solidservice.link/api/v1/metadata/entities'

Postman will automatically create a request from it.

This is particularly convenient when someone gives you a cURL command and you want to inspect or modify it using Postman’s interface.

3. Export / Import Collections as JSON

A Collection is a group of related requests.

For example:

Users API
├── GET Users
├── GET User
├── POST User
├── PUT User
└── DELETE User

Collections are useful for grouping all the requests required to work with an API.

Export a Collection

In the Postman sidebar:

Collections → Right-click your collection → Export

Choose the desired collection format.

Postman generates a .json file containing the collection.

Example:

users-api.postman_collection.json

Import a Collection

To import an existing collection:

Import → Select the .json collection file

Postman will recreate the collection and all its requests.

4. Expected / In-Request Tests

Postman allows you to execute JavaScript after a request and automatically verify the response.

This is useful for automatically verifying that a response contains what you expect.

Tests are added in the Scripts → Post-response section.

For example:

pm.test("Status is 200", function () {
    pm.response.to.have.status(200);
});

You can test JSON responses as well.

For this response:

{
    "id": 123,
    "email": "test@example.com",
    "active": true
}

You could write:

const response = pm.response.json();
 
pm.test("User has an ID", function () {
    pm.expect(response.id).to.exist;
});
 
pm.test("User is active", function () {
    pm.expect(response.active).to.be.true;
});

You can have multiple tests in the same request:

const response = pm.response.json();
 
pm.test("Status is 200", function () {
    pm.response.to.have.status(200);
});
 
pm.test("Response contains an ID", function () {
    pm.expect(response.id).to.exist;
});
 
pm.test("Email is correct", function () {
    pm.expect(response.email).to.eql("test@example.com");
});

Postman displays the result of each test after the request executes.