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Postman

Introduction

Welcome to the Postman docs! This is the place to find official information on how to use Postman in your API projects.

If you're just starting to learn about APIs and Postman, you can use a variety of channels both in and outside Postman:

What are you here to learn about?

If you're learning to carry out a specific task or workflow in Postman, check out the following topics to find resources:

Making requests

If you're building a client app or just need to connect to an API, check out some Postman essentials:

Testing APIs

If you're testing an API, you can use Postman to automate various parts of the process:

Building and managing APIs

If you're developing a back-end, working API-first, or need to monitor API performance, Postman utilities can streamline your workflows:

Publishing APIs

If you're exposing an API for public use, Postman can support developer onboarding:

Collaborating with your team

If you're using Postman in your company or team, check out these guides to maximize your collaboration:

Developing with Postman

If you're integrating Postman with your CI/CD workflow or are developing with Postman APIs or libraries, check out these resources:

Providing feedback

Share your thoughts on the documentation and help the Postman team to improve it for yourself and other learners! To submit feedback, please create an issue on the documentation GitHub repo or post in the community forum.

Help improve Postman and have an impact on Postman's roadmap by sending your feedback directly to Postman's developer team. To submit feature requests, create an issue on the Postman GitHub repo.

To get the latest version of the Postman desktop app, visit the download page and select Download for your platform.

Contents

Note that the Postman team only tests, fixes bugs, and provides support for the app on Mac, Windows, Linux, and the web.

Installing Postman on Mac

Download and unzip the app using the built-in Archive Utility app. Double-click Postman. When prompted, move the file to your Applications folder—this will ensure that future updates can be installed correctly.

The minimum OS version supported is macOS 10.11 (El Capitan).

You may encounter a "Library not loaded" error if you attempt to unzip and install Postman using a third-party app—using the default Archive Utility for Mac should resolve this.

Installing Postman on Windows

Download the app. Double-click the exe file to install it.

Postman supports Windows 7 and above. Both ia32 (x86) and x64 (amd64) installers are available for Windows. Windows for ARM devices is possible by using the ia32 binary.

Installing Postman on Linux

You can install Postman on Linux by manually downloading it, using the Snap store link, or with the command snap install postman.

To install manually, download and unzip the app, for example into the opt directory. You will need sudo privileges.

To start the app from a launcher icon, create a desktop file, naming it Postman.desktop and saving it in the following location:

~/.local/share/applications/Postman.desktop

Enter the following content in the file—replacing opt if you extracted the file somewhere else—and save it:

[Desktop Entry]
Encoding=UTF-8
Name=Postman
Exec=/opt/Postman/app/Postman %U
Icon=/opt/Postman/app/resources/app/assets/icon.png
Terminal=false
Type=Application
Categories=Development;

Postman supports the following distributions:

  • Ubuntu 14.04 and newer

  • Fedora 24

  • Debian 8 and newer

The support of certain Linux distributions depends on if they are supported by Electron. Refer to Electron's documentation.

It is recommended you install Snap as it includes all the libraries that the app needs and they are bundled with the app itself.

Avoid starting Postman using the sudo command, as it will create permission issues on the files created by Postman.

Make sure you have read/write permission for the ~/.config folder where Postman stores information.

If you are an Ubuntu 18 user, you will also need to install the libgconf-2-4 package with the command apt-get install libgconf-2-4

Using Postman on the web

You can use Postman in your web browser to carry out your API development and testing tasks in conjunction with the Postman Agent. To access Postman on the web, visit go.postman.co/home.

Browser requirements

Postman’s web application is optimized for the following browsers:

  • Chrome (78 and higher)

  • Firefox (76 and higher)

  • Edge (79 and higher)

  • Safari (13.1.1 and higher)

Installing the Postman desktop agent

If you are using the Postman web client, you will need to also download the Postman desktop agent. You will be prompted to download and install the agent so that you can make requests from the web. You can also download the agent directly from the Downloads page.

The Postman agent overcomes the Cross Object Resource Sharing (CORS) limitations of browsers, and facilitates API request sending from your browser version of Postman. Once you have the agent installed you will be able to use it with web requests.

You can either enable Auto-select option or manually select the agent (Cloud, Desktop, or Browser) you would like to use for your requests.

Once you enable the option for Auto-select, Postman will automatically select the best agent for your requests.

You can select the Cloud Agent if you want to send HTTP requests via Postman's secure cloud servers. While using the locally running Postman, it is recommended you use the Desktop Agent. Using the Browser Agent for your web requests has some limitations.

If you try to send a request and it isn't successful because the agent is not selected, you will see a link in the response area which you can select to switch to the agent and try your request again. Read more about the agent.

Web limitations

Postman on the web is under active development, but there are a few features you can currently only access in the desktop app and not in your web browser:

  • Live preview: You will not see all of your request headers update live as you enter your request configurations as you do in the desktop Postman app—you will only see Authorization headers update as you edit.

  • Saving responses to file

  • Certificates and Proxy: These will take the browser defined value and cannot be overridden by Postman.

  • Postman Interceptor

Updating Postman

The native Postman apps will notify you when a major update is available. For other updates you will see a dot on the settings icon. If the indicator is red instead of orange, it indicates a failed update.

Select the update option to download or install the latest update. You will see a notification when the download is complete, prompting you to restart the Postman app to apply the updates. If you're not ready to update yet, choose Later to auto-update the next time you launch the app.

You can configure your preferences to enable automatic download for major updates in Settings > Update. Postman automatically downloads minor updates and bug fixes.

Postman Chrome app (deprecated)

The Postman Chrome app is deprecated—if you're using the Chrome app, you can retain your data when you switch to the native app either by syncing with a Postman account you're signed into, or by exporting from Chrome and importing into the native app.

The native app is built on Electron, and overcomes a number of restrictions of the Chrome platform.

  • The native apps let you work with cookies directly.

  • Unlike the Chrome app, no separate extension for the Interceptor is needed.

  • The native apps come with a built-in proxy that you can use to capture network traffic.

  • The native apps are not restricted by the Chrome standards for the menu bar. You can check for updates, create Postman Windows and tabs, and edit preferences.

  • The native apps let you send headers like Origin and User-Agent. These are restricted in the Chrome app.

  • The "don't follow redirects" option exists in the native apps to prevent requests that return a 300-series response from being automatically redirected—doing this in the Chrome app requires the Interceptor extension.

  • The native app has a built-in console, which allows you to view the network request details for API calls.

Migrating to the native app

To switch from the Chrome app to native, download Postman and sign in to your account. Start the native app, and your history and collections will be automatically synced.

Alternatively, if you don't want to sign in to your Postman account, you can bulk export your Postman data from the Chrome app, and then bulk import into the new native app at Settings > Data.

Note that importing will overwrite your existing data. For more on bulk import, see Importing Postman data.

Using Postman behind a firewall

Postman's infrastructure runs on Amazon's AWS platform. If you are operating behind a network firewall, you will need to allow the following domains to make WebSocket connections for Postman:

  • \*.getpostman.com

  • \*.postman.co

  • \*.pstmn.io

  • \*postman.com

By default, WebSocket connections use the same ports as HTTP (80) and HTTPS (443).

Postman does not have a fixed IP range that can be provided. If necessary, please refer to the current AWS IP ranges and allow the broad range provided.

Troubleshooting your Postman installation

If you encounter any issues installing and running Postman, check out the following tips. If these do not help, please refer to the installation posts on the community forum and create a new post if your issue is not already covered.

Update failed error

If you see an Update Failed notification in Postman, you can use the DevTools to investigate.

Open the DevTools using View > Developer > Show DevTools (Current View). Some known errors are as follows:

  • Error message: Cannot update while running on a read-only volume

    • This error means that the app user does not have write permission in the directory where Postman is installed. To resolve the problem, move Postman to a directory where the user has write permissions, for example the /Application directory for Mac, and to the home directory for Linux.

  • Error message: Code signature at URL file:///... did not pass validation: code object is not signed at all

    • This error means that there are multiple updates running at the same time. This can happen when the app is opened before the previous update could finish. To resolve the problem, quit and reopen the app.

Update button not available

If you are using Postman for Linux, and installed the app with the Ubuntu Software Center or Snap Store, you may not see a Check for updates button. This is because the updates are handled by the store, which should automatically update Postman on a regular cadence.

Next steps

If you're having trouble with installation or updates, reach out for Postman support. If your installation is working as expected, send your first request!

Postman JavaScript reference

Postman provides JavaScript APIs that you can use in your request scripts. The pm object provides most of the functionality for testing your request and response data, with the postman object providing some additional workflow control.

Contents

The pm object

You will carry out most of the Postman JavaScript API functionality using pm.*, which provides access to request and response data, and variables.

Using variables in scripts

You can access and manipulate variables at each scope in Postman using the pm API.

You can use dynamic variables to generate values when your requests run.

Postman supports a variety of variable scopes. The pm object provides methods for accessing global, collection, and environment variables specifically, and pm.variables methods for accessing variables at different scopes as well as setting local variables.

  • Check if there is a Postman variable in the current scope:

pm.variables.has(variableName:String):function → Boolean

  • Get the value of the Postman variable with the specified name:

pm.variables.get(variableName:String):function → *

  • Set a local variable with the specified name and value:

pm.variables.set(variableName:String, variableValue:*):function

  • Return the resolved value of a dynamic variable inside a script using the syntax {{$variableName}}:

pm.variables.replaceIn(variableName:String):function: → *

For example:

const stringWithVars = pm.variables.replaceIn("Hi, my name is {{$randomFirstName}}");
console.log(stringWithVars);

  • Return an object containing all variables with their values in the current scope. Based on the order of precedence, this will contain variables from multiple scopes.

pm.variables.toObject():function → Object

Variable scope determines the precedence Postman gives to variables when you reference them, in order of increasing precedence:

  • Global

  • Environment

  • Collection

  • Data

  • Local

The variable with the closest scope overrides any others. For example, if you have variables named score in both the current collection and the active environment, and you call pm.variables.get('score'), Postman will return the current value of the environment variable. When you set a variable value using pm.variables.set, the value is local and will only persist for the current request or collection run.

//collection var 'score' = 1
//environment var 'score' = 2

//first request run
console.log(pm.variables.get('score'));//outputs 2
console.log(pm.collectionVariables.get('score'));//outputs 1
console.log(pm.environment.get('score'));//outputs 2

//second request run
pm.variables.set('score', 3);//local var
console.log(pm.variables.get('score'));//outputs 3

//third request run
console.log(pm.variables.get('score'));//outputs 2

See the Postman Collection SDK Variables reference for more detail.

You can also access variables defined in the individual scopes via pm.environment, pm.collectionVariables, and pm.globals.

Using environment variables in scripts

Your scripts can use the pm.environment methods to access and manipulate variables in the active (currently selected) environment.

  • The name of the active environment:

pm.environment.name:String

  • Check whether the environment has a variable with the specified name:

pm.environment.has(variableName:String):function → Boolean

  • Get the variable with the specified name in the active environment:

pm.environment.get(variableName:String):function → *

  • Set the variable with the specified name and value in the active environment:

pm.environment.set(variableName:String, variableValue:*):function

  • Return the resolved value of a dynamic variable inside a script using the syntax {{$variableName}}:

pm.environment.replaceIn(variableName:String):function → *

For example:

//environment has vars firstName and age
const stringWithVars = pm.environment.replaceIn("Hi, my name is {{firstName}} and I am {{age}}.");
console.log(stringWithVars);

  • Return all variables with their values in the active environment in a single object:

pm.environment.toObject():function → Object

  • Remove a variable from the active environment, specifying the variable by name:

pm.environment.unset(variableName:String):function

  • Clear all variables in the active environment:

pm.environment.clear():function

Note that your ability to edit variables depends on your access level in the workspace.

Using collection variables in scripts

Your scripts can use the pm.collectionVariables methods to access and manipulate variables in the collection.

  • Check whether there is a variable in the collection with the specified name:

pm.collectionVariables.has(variableName:String):function → Boolean

  • Return the value of the collection variable with the specified name:

pm.collectionVariables.get(variableName:String):function → *

  • Set a collection variable with the specified name and value:

pm.collectionVariables.set(variableName:String, variableValue:*):function

  • Return the resolved value of a dynamic variable inside a script using the syntax {{$variableName}}:

pm.collectionVariables.replaceIn(variableName:String):function → *

For example:

//collection has vars firstName and age
const stringWithVars = pm.collectionVariables.replaceIn("Hi, my name is {{firstName}} and I am {{age}}.");
console.log(stringWithVars);

  • Return all variables with their values in the collection in an object:

pm.collectionVariables.toObject():function → Object

  • Remove the specified variable from the collection:

pm.collectionVariables.unset(variableName:String):function

  • Clear all variables from the collection:

pm.collectionVariables.clear():function

Using global variables in scripts

Your scripts can use the pm.globals methods to access and manipulate variables at global scope within the workspace.

  • Check where there is a global variable with the specified name:

pm.globals.has(variableName:String):function → Boolean

  • Return the value of the global variable with the specified name:

pm.globals.get(variableName:String):function → *

  • Set a global variable with specified name and value:

pm.globals.set(variableName:String, variableValue:*):function

  • Return the resolved value of a dynamic variable inside a script using the syntax {{$variableName}}:

pm.globals.replaceIn(variableName:String):function → String

For example:

//globals include vars firstName and age
const stringWithVars = pm.globals.replaceIn("Hi, my name is {{firstName}} and I am {{age}}.");
console.log(stringWithVars);

  • Return all global variables and their values in an object:

pm.globals.toObject():function → Object

  • Remove the specified global variable:

pm.globals.unset(variableName:String):function

  • Clear all global variables in the workspace:

pm.globals.clear():function

Note that your ability to edit variables depends on your access level in the workspace.

Using data variables in scripts

Your scripts can use the pm.iterationData methods to access and manipulate variables from data files during a collection run.

  • Check whether a variable with the specified name exists in the current iteration data:

pm.iterationData.has(variableName:String):function → boolean

  • Return a variable from the iteration data with the specified name:

pm.iterationData.get(variableName:String):function → *

  • Return the iteration data variables in an object:

pm.iterationData.toObject():function → Object

  • Convert the iterationData object to JSON format:

pm.iterationData.toJSON():function → *

  • Remove the specified variable:

pm.iterationData.unset(key:String):function

Scripting with request and response data

A variety of methods provide access to request and response data in Postman scripts, including pm.request, pm.response, pm.info, and pm.cookies. Additionally you can send requests using pm.sendRequest.

Scripting with request data

The pm.request object provides access to the data for the request the script is running within. For a Pre-request Script this is the request that is about to run, and for a Test script this is the request that has already run.

You can use the pm.request object pre-request scripts to alter various parts of the request configuration before it runs.

The pm.request object provides the following properties and methods:

  • The request URL:

pm.request.url:Url
pm.request.headers:HeaderList

  • The HTTP request method:

pm.request.method:String

  • The data in the request body. This object is immutable and cannot be modified from scripts:

pm.request.body:RequestBody

  • Add a header with the specified name and value for the current request:

pm.request.headers.add(header:Header):function

For example:

pm.request.headers.add({
  key: "client-id",
  value: "abcdef"
});

  • Delete the request header with the specified name:

pm.request.headers.remove(headerName:String):function

  • Insert the specified header name and value (if the header does not exist, otherwise the already existing header will update to the new value):

pm.request.headers.upsert({key: headerName:String, value: headerValue:String}):function)

See the Postman Collection SDK Request reference for more detail.

Scripting with response data

The pm.response object provides access to the data returned in the response for the current request in scripts added to the Tests.

The pm.response object provides the following properties and methods:

  • The response status code:

pm.response.code:Number

  • The status text string:

pm.response.status:String
pm.response.headers:HeaderList

  • The time the response took to receive in milliseconds:

pm.response.responseTime:Number

  • The size of the response received:

pm.response.responseSize:Number

  • The response text:

pm.response.text():Function → String

  • The response JSON, which you can use to drill down into the properties received:

pm.response.json():Function → Object

See the Postman Collection SDK Response reference for more detail.

Scripting with request info

The pm.info object provides data related to the request and the script itself, including name, ID, and iteration count.

The pm.info object provides the following properties and methods:

  • The event, which will be either "prerequest" or "test" depending on where the script is executing within the request:

pm.info.eventName:String
pm.info.iteration:Number

  • The total number of iterations that are scheduled to run:

pm.info.iterationCount:Number

  • The saved name of the request running:

pm.info.requestName:String

  • A unique GUID that identifies the running request:

pm.info.requestId:String

Scripting with request cookies

The pm.cookies object provides access to the list of cookies associated with the request.

The pm.cookies object provides the following properties and methods:

  • Check whether a particular cookie (specified by name) exists for the requested domain:

pm.cookies.has(cookieName:String):Function → Boolean

  • Get the value of the specified cookie:

pm.cookies.get(cookieName:String):Function → String

  • Get a copy of all cookies and their values in an object. Returns any cookies that are defined for the request domain and path:

pm.cookies.toObject():Function → Object

See the Postman Collection SDK Cookie List reference for more detail.

You can also use pm.cookies.jar to specify a domain for access to request cookies.

To enable programmatic access via the pm.cookies.jar methods, first whitelist the cookie URL.

  • Access the cookie jar object:

pm.cookies.jar():Function → Object

For example:

const jar = pm.cookies.jar();
//cookie methods...

  • Set a cookie using name and value:

jar.set(URL:String, cookie name:String, cookie value:String, callback(error, cookie)):Function → Object
jar.set(URL:String, { name:String, value:String, httpOnly:Bool }, callback(error, cookie)):Function → Object

For example:

const jar = pm.cookies.jar();
jar.set("httpbin.org", "session-id", "abc123", (error, cookie) => {
  if (error) {
    console.error(`An error occurred: ${error}`);
  } else {
    console.log(`Cookie saved: ${cookie}`);
  }
});

  • Get a cookie from the cookie jar:

jar.get(URL:String, cookieName:String, callback (error, value)):Function → Object

  • Get all the cookies from the cookie jar. The cookies are available in the callback function:

jar.getAll(URL:String, callback (error, cookies)):Function

  • Remove a cookie:

jar.unset(URL:String, token:String, callback(error)):Function → Object

  • Clear all cookies from the cookie jar:

jar.clear(URL:String, callback (error)):Function → Object

See the Postman Collection SDK Cookie reference for more detail.

Sending requests from scripts

You can use the pm.sendRequest method to send a request asynchronously from a Pre-request or Test script. This allows you to execute logic in the background if you are carrying out computation or sending multiple requests at the same time without waiting for each to complete. You can avoid blocking issues by adding a callback function so that your code can respond when Postman receives a response. You can then carry out any additional processing you need on the response data.

You can pass the pm.sendRequest method a URL string, or can provide a complete request configuration in JSON including headers, method, body, and more.

// Example with a plain string URL
pm.sendRequest('https://postman-echo.com/get', (error, response) => {
  if (error) {
    console.log(error);
  } else {
  console.log(response);
  }
});

// Example with a full-fledged request
const postRequest = {
  url: 'https://postman-echo.com/post',
  method: 'POST',
  header: {
    'Content-Type': 'application/json',
    'X-Foo': 'bar'
  },
  body: {
    mode: 'raw',
    raw: JSON.stringify({ key: 'this is json' })
  }
};
pm.sendRequest(postRequest, (error, response) => {
  console.log(error ? error : response.json());
});

// Example containing a test
pm.sendRequest('https://postman-echo.com/get', (error, response) => {
  if (error) {
    console.log(error);
  }

  pm.test('response should be okay to process', () => {
    pm.expect(error).to.equal(null);
    pm.expect(response).to.have.property('code', 200);
    pm.expect(response).to.have.property('status', 'OK');
  });
});

See the Request definition and Response structure reference docs for more detail.

Scripting workflows

The postman object provides the setNextRequest method for building request workflows when you use the collection runner or Newman.

Note that setNextRequest has no effect when you run requests using the Send button, it only comes into effect when you run a collection.

When you run a collection (using the collection runner or Newman), Postman will run your requests in a default order or an order you specify when you set up the run. However, you can override this execution order using postman.setNextRequest to specify which request should run next.

  • Run the specified request after this one (the request name as defined in the collection e.g. "Get customers"):

postman.setNextRequest(requestName:String):Function

  • Run the specified request after this one (the request ID returned by pm.info.requestId):

postman.setNextRequest(requestId:String):Function

For example:

//script in another request calls:
//pm.environment.set('next', pm.info.requestId)
postman.setNextRequest(pm.environment.get('next'));

Scripting visualizations

Use pm.visualizer.set to specify a template to display response data in the visualizer.

pm.visualizer.set(layout:String, data:Object, options:Object):Function

  • layout required

  • data optional

    • JSON object that binds to the template and you can access it inside the template string

  • options optional

Example usage:

var template = `<p>{{res.info}}</p>`;
pm.visualizer.set(template, {
    res: pm.response.json()
});

Building response data into visualizations

Use pm.getData to retrieve response data inside a visualization template string.

pm.getData(callback):Function

The callback function accepts two parameters:

Example usage:

pm.getData(function (error, data) {
  var value = data.res.info;
});

Writing test assertions

  • pm.test(testName:String, specFunction:Function):Function

You can use pm.test to write test specifications inside either the Pre-request or Tests scripts. Tests include a name and assertion—Postman will output test results as part of the response.

The pm.test method returns the pm object, making the call chainable. The following sample test checks that a response is valid to proceed.

pm.test("response should be okay to process", function () {
  pm.response.to.not.be.error;
  pm.response.to.have.jsonBody('');
  pm.response.to.not.have.jsonBody('error');
});

An optional done callback can be passed to pm.test, to test asynchronous functions.

pm.test('async test', function (done) {
  setTimeout(() => {
    pm.expect(pm.response.code).to.equal(200);
    done();
  }, 1500);
});

  • Get the total number of tests executed from a specific location in code:

pm.test.index():Function → Number

The pm.expect method allows you to write assertions on your response data, using ChaiJS expect BDD syntax.

pm.expect(assertion:*):Function → Assertion

You can also use pm.response.to.have.* and pm.response.to.be.* to build your assertions.

See Test examples for more assertions.

Using external libraries

require(moduleName:String):function → *

The require method allows you to use the sandbox built-in library modules. The list of available libraries is listed below with links to the corresponding documentation.

A number of NodeJS modules are also available to use in the sandbox:

In order to use a library, call the require method, pass the module name as a parameter, and assign the return object from the method to a variable.

Next steps

You can use tests to build Postman into your development projects in a variety of ways using Postman utilities.

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