context_regex_replace #

Description #

The context_regex_replace filter is used to replace and modify relevant information in the request context by using regular expressions.

Configuration Example #

A simple example is as follows:

flow:
  - name: test
    filter:
      - context_regex_replace:
          context: "_ctx.request.path"
          pattern: "^/"
          to: "/cluster:"
          when:
            contains:
              _ctx.request.path: /_search
      - dump:
          request: true

This example replaces curl localhost:8000/abc/_search in requests with curl localhost:8000/cluster:abc/_search.

Parameter Description #

Name	Type	Description
context	string	Request context and corresponding key
pattern	string	Regular expression used for matching and replacement
to	string	Target string used for replacement

A list of context variables that can be modified is provided below:

Name	Type	Description
_ctx.request.uri	string	Complete URL of a request
_ctx.request.path	string	Request path
_ctx.request.host	string	Request host
_ctx.request.body	string	Request body
_ctx.request.body_json.[JSON_PATH]	string	Path to the JSON request object
_ctx.request.query_args.[KEY]	string	URL query request parameter
_ctx.request.header.[KEY]	string	Request header information
_ctx.response.header.[KEY]	string	Response header information
_ctx.response.body	string	Returned response body
_ctx.response.body_json.[JSON_PATH]	string	Path to the JSON response object