How to create regex

Question

can somebody help me how to create regex from this? I need only text after a_n: " so I need only this text. e.g. jgoijODIJGojsklfj4dgdg_797gsdg-df_gsdfh-dhfGSDhfdsg-dfg

{
  "a_n": "jgoijODIJGojsklfj4dgdg_797gsdg-df_gsdfh-dhfGSDhfdsg-dfg",
  "type": "something",
  "uuser": "userid",
  "expire": "6018"
}

This looks like json. Have you tried using a json parser to load and extract it? — , Sep 29 '17 at 08:34
It is response from post request and I need to use this value in next request header. I need it for jmeter so the best way should be regex or xpath.. — vb381, Sep 29 '17 at 08:37
regex and xpath are two entirely different things, and both aren't really suited for your use case I would think. Also you should give more context to your question - eg. use case, programming language, how the data will vary. — , Sep 29 '17 at 08:39
I have in jmeter POST request and in response data is text that I posted. I need from this text use value of a_n: in next request header. I was using for something similar (xml response) xpath extractor or regex extractor in jmeter. There can be used also some javascript, or beanshell script but I thought it would be easier via regex as I am not very familier with scripts... — vb381, Sep 29 '17 at 08:48
Can you see if the answers to this question are helpful: https://stackoverflow.com/questions/18562060/jmeter-extracting-fields-parsing-json-response ? — , Sep 29 '17 at 08:50
Thanks to all. I have installed json extractor plugin to jmeter so I am trying with this, but if can somebody help me also with json it would be great. — vb381, Sep 29 '17 at 09:56
Possible duplicate of [Jmeter extracting fields/parsing JSON response](https://stackoverflow.com/questions/18562060/jmeter-extracting-fields-parsing-json-response) — , Sep 29 '17 at 10:33

filype · Answer 1 · 2017-09-29T08:41:34.847

1

You can achieve this with JSONStream.

cat file.json | JSONStream '.a_n'

And also with jq:

jq .a_n file.json

edited Sep 29 '17 at 08:41

answered Sep 29 '17 at 08:36

filype

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score 1 · Answer 2 · answered Sep 29 '17 at 08:38

1

If you can, just use a JSON parser to get the value. Otherwise you can use

/{.*\"a_n\": \"(.*)\".*/

answered Sep 29 '17 at 08:38

LW001

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score 1 · Answer 3 · answered Sep 29 '17 at 08:52

1

Please have a look (how to use a regular expression to extract json fields?)

regex should be,

/"a_n":\ ?"((\\"|[^"])*)"/i

answered Sep 29 '17 at 08:52

Ashraful Karim Miraz

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score 0 · Answer 4 · answered Oct 02 '17 at 02:42

To extract this in JMeter:

Add a jp@gc - JSON Path Extractor under your request sampler.
To extract the required data, you have to set like this:

Your extracted value will be saved in the variable Jsonvar.
Now You can use this variable other subsequent requests.

score 0 · Answer 5 · answered Oct 02 '17 at 05:05

JMeter's Regular Expression Extractor uses Perl-5 style regular expressions so the relevant configuration would be:

Regular Expression: "a_n": "(.+?)"
Template: $1$

Also be aware that it makes more sense to use JSON Extractor to work with JSON responses. The relevant JSON Path query would be as simple as $.a_n

Demo:

More information: API Testing With JMeter and the JSON Extractor

How to create regex

5 Answers5