how to extract json path and find array length?

Question

how to extract JSON path and find array length using java? for my below response data. I need to validate array length should be equal to '7' in Jmeter assertion.

[
  [
    "Week",
    "Event Count"
  ],
  [
    "3/13/17",
    "1"
  ],
  [
    "3/20/17",
    "1"
  ],
  [
    "3/27/17",
    "1"
  ],
  [
    "4/3/17",
    "1"
  ],
  [
    "4/10/17",
    "1"
  ],
  [
    "4/17/17",
    "1"
  ]
]

Answer 1

1. Add JSON Extractor as a child of the request which produces the above JSON response and configure it as follows:

   • Variable names: anything meaningful, i.e. week
   • JSON Path Expressions: $[*]

   • Match No: -1

     

   This will produce the following JMeter Variables (you can validate them using Debug Sampler):

   week_1=["Week","Event Count"]
   week_2=["3\/13\/17","1"]
   week_3=["3\/20\/17","1"]
   week_4=["3\/27\/17","1"]
   week_5=["4\/3\/17","1"]
   week_6=["4\/10\/17","1"]
   week_7=["4\/17\/17","1"]
   week_matchNr=7
   

   You are particularly interested in the latter one

   

2. Add Response Assertion as a child of the same request and configure it as follows:

   • Apply to: JMeter Variable -> week_matchNr
   • Pattern Matching Rules: Equals
   • Patterns to Test: 7

   

   This way your sampler will pass if number of matches will be equal to 7 and otherwise it will fail. See How to Use JMeter Assertions in Three Easy Steps article to learn more about using assertions in JMeter tests.