How to read the JSON request / response which values are encoded in Base64

Question

I recorded a Mobile Native application (HTTPS/JSON) using Jmeter.

The requests and responses captured as in JSON format and I am not able to view the values that are passed in the requests because they are encoded in base64.

How do I proceed?

Answer 1

You can decode Base64 on the fly via Beanshell PostProcessor.

1. Add Beanshell Post Processor as a child of the request you want to decode

2. Put the following code into Beanshell Post Processor's "Script" area

   import org.apache.commons.codec.binary.Base64;
   prev.setResponseData(Base64.decodeBase64(data));
   

3. View decoded response via View Results Tree Listener

Explanation:

• Base64.decodeBase64() - self explanatory, it's the method of a class from Commons Codec package which provides Base64 encoding and decoding operations
• prev is a shorthand for SampleResult class instance holding result of the parent sampler
• data is the byte array representing parent sampler response data.

See How to use BeanShell: JMeter's favorite built-in component guide for more details on what can be done via Beanshell scripting.