2023-08-18 02:43:28 +05:30

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---
title: "Extractors"
---
## Extractors
Extractors can be used to extract and display in results a match from the response returned by a module.
### Types
Multiple extractors can be specified in a request. As of now we support five type of extractors.
1. **regex** - Extract data from response based on a Regular Expression.
2. **kval** - Extract `key: value`/`key=value` formatted data from Response Header/Cookie
3. **json** - Extract data from JSON based response in JQ like syntax.
4. **xpath** - Extract xpath based data from HTML Response
5. **dsl** - Extract data from the response based on a DSL expressions.
### Regex Extractor
Example extractor for HTTP Response body using **regex** -
```yaml
extractors:
- type: regex # type of the extractor
part: body # part of the response (header,body,all)
regex:
- "(A3T[A-Z0-9]|AKIA|AGPA|AROA|AIPA|ANPA|ANVA|ASIA)[A-Z0-9]{16}" # regex to use for extraction.
```
### Kval Extractor
A **kval** extractor example to extract `content-type` header from HTTP Response.
```yaml
extractors:
- type: kval # type of the extractor
kval:
- content_type # header/cookie value to extract from response
```
Note that `content-type` has been replaced with `content_type` because **kval** extractor does not accept dash (`-`) as input and must be substituted with underscore (`_`).
### JSON Extractor
A **json** extractor example to extract value of `id` object from JSON block.
```yaml
- type: json # type of the extractor
part: body
name: user
json:
- '.[] | .id' # JQ like syntax for extraction
```
For more details about JQ - https://github.com/stedolan/jq
### Xpath Extractor
A **xpath** extractor example to extract value of `href` attribute from HTML response.
```yaml
extractors:
- type: xpath # type of the extractor
attribute: href # attribute value to extract (optional)
xpath:
- '/html/body/div/p[2]/a' # xpath value for extraction
```
With a simple [copy paste in browser](https://www.scientecheasy.com/2020/07/find-xpath-chrome.html/), we can get the **xpath** value form any web page content.
### DSL Extractor
A **dsl** extractor example to extract the effective `body` length through the `len` helper function from HTTP Response.
```yaml
extractors:
- type: dsl # type of the extractor
dsl:
- len(body) # dsl expression value to extract from response
```
### Dynamic Extractor
Extractors can be used to capture Dynamic Values on runtime while writing Multi-Request templates. CSRF Tokens, Session Headers, etc. can be extracted and used in requests. This feature is only available in RAW request format.
Example of defining a dynamic extractor with name `api` which will capture a regex based pattern from the request.
```yaml
extractors:
- type: regex
name: api
part: body
internal: true # Required for using dynamic variables
regex:
- "(?m)[0-9]{3,10}\\.[0-9]+"
```
The extracted value is stored in the variable **api**, which can be utilised in any section of the subsequent requests.
If you want to use extractor as a dynamic variable, you must use `internal: true` to avoid printing extracted values in the terminal.
An optional regex **match-group** can also be specified for the regex for more complex matches.
```yaml
extractors:
- type: regex # type of extractor
name: csrf_token # defining the variable name
part: body # part of response to look for
# group defines the matching group being used.
# In GO the "match" is the full array of all matches and submatches
# match[0] is the full match
# match[n] is the submatches. Most often we'd want match[1] as depicted below
group: 1
regex:
- '<input\sname="csrf_token"\stype="hidden"\svalue="([[:alnum:]]{16})"\s/>'
```
The above extractor with name `csrf_token` will hold the value extracted by `([[:alnum:]]{16})` as `abcdefgh12345678`.
If no group option is provided with this regex, the above extractor with name `csrf_token` will hold the full match (by `<input name="csrf_token"\stype="hidden"\svalue="([[:alnum:]]{16})" />`) as `<input name="csrf_token" type="hidden" value="abcdefgh12345678" />`.