CGI::ArgChecker - An extensible CGI parameter validation module (allowing commonly used checks on parameters to be called more concisely and consistently).
use CGI::ArgChecker;
$checker = new CGI::Argchecker; $checker->register_check($name, \&sub); $checker->error_handler(\&errhandler); $checker->argcheck($CGI_query_object, 'param_name' => [ 'expectation', ... ], ... );
Note: Since this is really a simple wrapper around String::Checker(3), most of the interesting reading is in that document (i.e. the definition of an 'expectation'). The documentation that follows assumes you are pretty familiar with String::Checker(3), and focuses on the additional functionality provided by this module.
The argcheck() method takes a CGI object (can be any of the CGI modules which
have a param method for fetching a parameter...) followed by a list of
parameter_name/expectation_list_reference pairs. The parameter name is
the name of a CGI variable to examine. The expectation list is
precisely the same as the String::Checker(3) expectation list.
Each parameter will be retrieved from the CGI object using the param() method,
checked against all the expectations, and then the result of all checks will
be stored for returning. If all parameters pass all expectations, a
reference to a hash will be returned, containing parameter_name/parameter_value
pairs. If any expectation fails, the hash will still be returned. To
check whether any errors occurred, check the 'ERROR' hash value (a boolean
flag value). For every expectation which fails, in addition, an error
handling routine (described below) will be called.
Using the error_handler() method, you can register a chunk of code which will
be called for every expectation which fails. This subroutine will be called
with two arguments: the name of the parameter which failed, and the name of
the expectation which failed. The return value of the error handling code
is ignored.
Hopefully none.
J. David Lowe, dlowe@webjuice.com
perl(1), String::Checker(3)