How to Build a Point¶

Let us recall the list of FAST DSL parsers and filters available for use in the point.

HTTP parser:
- URI filter;
- Path filter;
- Action_name filter;
- Action_ext filter;
- Get filter;
- Header filter;
- Post filter;
Form_urlencoded parser;
Multipart parser;
Cookie parser;
XML parser:
Json_doc parser:
- Json_obj filter;
- Json_array filter;
GZIP parser;
Base64 parser;
Array filter;
Hash filter.

It is recommended that points be assembled from right to left for an easier understanding of which parsers and filters should be included in the point. Move from smaller to larger parts of the request when building a point.

Point parts divider

The parts of the point must be divided using the _ symbol.

Example 1¶

Let us suppose that you need to build a point that refers to the decoded value of the uid parameter in the following request:

GET http://example.com/main/login/?uid=MDEyMzQ=

where MDEyMzQ= is the Base64-encoded 01234 string.

Because the point must refer to the value of the request element, we need to include the value service word in the point.

The current state of the point: value.
The point must refer to the decoded value, but the desired value is encoded with the Base64 encoding in the request. The BASE64 parser name has to be added to the left side of the point to decode the value.

The current state of the point: BASE64_value.
The point must refer to the uid parameter value. Add the uid parameter name to the left side of the point to refer to the desired parameter value.

The current state of the point: uid_BASE64_value.
The point must refer to the value of the parameter that is passed in the baseline request query string. Add the GET filter name to the left side of the point to refer to the query string parameter value.

The current state of the point: GET_uid_BASE64_value.

To meet the conditions of the example, the point obtained in the fourth step can be added to the extension in one of the following ways:

not surrounded by any of the service symbols.
surrounded by apostrophes ('GET_uid_BASE64_value').
surrounded by quotation marks ("GET_uid_BASE64_value").

Example 2¶

Let us suppose that you need to build a point that refers to the 01234 value of the passwd parameter in the

POST http://example.com/login/index.php HTTP/1.1
Content-Type: application/x-www-form-urlencoded

request with the

username=admin&passwd=01234.

body.

Because the point must refer to the value of the request element, we need to include the value service word in the point.

The current state of the point: value.
The point must refer to the passwd parameter value. Add the passwd parameter name to the left side of the point to refer to the desired parameter value.

The current state of the point: passwd_value.
The point must refer to the value of the parameter that is passed in the form-urlencoded format. This can be derived from the value of the Content-Type header in the baseline request. Add the name of the Form_urlencoded parser in upper case to the left side of the point in order to refer to the value of the parameter passed in the form-urlencoded value.

The current state of the point: FORM_URLENCODED_passwd_value.
The point must refer to the value of the parameter that is passed in the request body. Add the name of the POST parser to the left side of the point to refer to the value of the request body parameter.

The current state of the point: POST_FORM_URLENCODED_passwd_value.

To meet the conditions of the example, the point obtained in the fourth step can be added to the extension in one of the following ways:

not surrounded by any of the service symbols.
surrounded by apostrophes ('POST_FORM_URLENCODED_passwd_value').
surrounded by quotation marks ("POST_FORM_URLENCODED_passwd_value").

Example 3¶

Let us suppose that you need to build a point that refers to the abcde value of the secret-word cookie in the following request:

GET /main/index.php HTTP/1.1
Host: example.com
Cookie: username=John. secret-word=abcde.

Because the point must refer to the value of the request element, we need to include the value service word into the point.

The current state of the point: value.
The point must refer to the secret-word cookie value. Add the secret-word name of the cookie to the left side of the point to refer to the desired cookie value.

The current state of the point: secret-word_value.
The point must refer to the value of the cookie. Add the name of the COOKIE parser to the left side of the point to refer to the cookie value.

The current state of the point: COOKIE_secret-word_value.
The point must refer to the value that is passed in the Cookie header. Add the name of the Cookie header to the left side of the point to refer to the header named Cookie.

The current state of the point: Cookie_COOKIE_secret-word_value.
The point must refer to the value that is passed in the header. Add the name of the HEADER filter to the left side of the point to refer to the header value.

The current state of the point: HEADER_Cookie_COOKIE_secret-word_value.

To meet the conditions of the example, the point obtained in the fourth step can be added to the extension in one of the following ways:

not surrounded by any of the service symbols.
surrounded by apostrophes ('HEADER_Cookie_COOKIE_secret-word_value').
surrounded by quotation marks ("HEADER_Cookie_COOKIE_secret-word_value").