How to perform API testing with JMeter using BlazeMeter

For recording API, I am going to use Blazemeter. BlazeMeter is a commercial, self-service load testing platform as a service (PaaS), which is compatible with open-source Apache JMeter. It is a performance testing framework from the Apache Software Foundation.

It is an Open-source tool which is used by most of developer's, QA for testing the API of an Application.

How to Record API from Blazemeter.

a. Open the Chrome Browser.
b. Add the Extension of Blazemeter.
c. Click on the Blazemeter icon on the chrome.
d. Recording API has been started.
e. Perform testing on the web app and stop Recording.

As you can see the above image:

1) It displays the number of API which has been recorded.

2) First You need to Sign up and then you can start testing with BlazeMeter.

3) You can direct off the recording from the Button.

4) On the click of this red button, recording is started.

5)  You can give the name of your Test case.

6) As soon as click on the Red button, Parallel 2 button gets enabled. First one is Pause and the Second one is Stop.

f. Click on the .jmx button it import the file into the .jmx format. As see the image below:

How to add a .jmx file into JMeter.

1. Open JMeter.
2. Click on the File-> Open then select the .jmx file which you just downloaded. That .jmx File is added in the Jmeter as show below:

After that add few listeners for check the status of our API.

a) Graph Results

b) Save Response to a file.

c) Aggregate Report

d) View Result in Table

e) View Result in Tree

f) Summary Report

3. Now you can see the response of the API in the Image below:

Conclusion: Blazemter is a very useful tool for API testing. One of the best part of Blazemeter only records the API from your web or mobile Application. This tool is compatible with JMeter and selenium also. After export .jmx file into JMeter, you don't need to add thread/users. It automatically adds thread and assertion which is needed in the HTTP request.