Constants(3p)

NAME
Apache::Constants - Constants defined in apache header files

SYNOPSIS
    use Apache::Constants;
    use Apache::Constants ':common';
    use Apache::Constants ':response';

DESCRIPTION
Server constants used by apache modules are defined in httpd.h and other header files, this module gives Perl access to those constants.

EXPORT TAGS

common
    This tag imports the most commonly used constants.

     OK
     DECLINED
     DONE
     NOT_FOUND
     FORBIDDEN
     AUTH_REQUIRED
     SERVER_ERROR

response
    This tag imports the common response codes, plus these response codes:

     DOCUMENT_FOLLOWS
     MOVED
     REDIRECT
     USE_LOCAL_COPY
     BAD_REQUEST
     BAD_GATEWAY
     RESPONSE_CODES
     NOT_IMPLEMENTED
     CONTINUE
     NOT_AUTHORITATIVE

    CONTINUE and NOT_AUTHORITATIVE are aliases for DECLINED.

methods
    This are the method numbers, commonly used with the Apache method_number method.

     METHODS
     M_CONNECT
     M_DELETE
     M_GET
     M_INVALID
     M_OPTIONS
     M_POST
     M_PUT
     M_TRACE
     M_PATCH
     M_PROPFIND
     M_PROPPATCH
     M_MKCOL
     M_COPY
     M_MOVE
     M_LOCK
     M_UNLOCK

options
    These constants are most commonly used with the Apache allow_options method:

     OPT_NONE
     OPT_INDEXES
     OPT_INCLUDES
     OPT_SYM_LINKS
     OPT_EXECCGI
     OPT_UNSET
     OPT_INCNOEXEC
     OPT_SYM_OWNER
     OPT_MULTI
     OPT_ALL

satisfy
    These constants are most commonly used with the Apache satisfies method:

     SATISFY_ALL
     SATISFY_ANY
     SATISFY_NOSPEC

remotehost
    These constants are most commonly used with the Apache get_remote_host method:

     REMOTE_HOST
     REMOTE_NAME
     REMOTE_NOLOOKUP
     REMOTE_DOUBLE_REV

http
    This is the full set of HTTP response codes: (NOTE: not all implemented here)

     HTTP_OK
     HTTP_MOVED_TEMPORARILY
     HTTP_MOVED_PERMANENTLY
     HTTP_METHOD_NOT_ALLOWED
     HTTP_NOT_MODIFIED
     HTTP_UNAUTHORIZED
     HTTP_FORBIDDEN
     HTTP_NOT_FOUND
     HTTP_BAD_REQUEST
     HTTP_INTERNAL_SERVER_ERROR
     HTTP_NOT_ACCEPTABLE
     HTTP_NO_CONTENT
     HTTP_PRECONDITION_FAILED
     HTTP_SERVICE_UNAVAILABLE
     HTTP_VARIANT_ALSO_VARIES

server
    These are constants related to server version:

     MODULE_MAGIC_NUMBER
     SERVER_VERSION
     SERVER_BUILT

config
    These are constants related to configuration directives:

     DECLINE_CMD

types
    These are constants related to internal request types:

     DIR_MAGIC_TYPE

override
    These constants are used to control and test the context of configuration directives.

     OR_NONE
     OR_LIMIT
     OR_OPTIONS
     OR_FILEINFO
     OR_AUTHCFG
     OR_INDEXES
     OR_UNSET
     OR_ALL
     ACCESS_CONF
     RSRC_CONF

args_how
     RAW_ARGS
     TAKE1
     TAKE2
     TAKE12
     TAKE3
     TAKE23
     TAKE123
     ITERATE
     ITERATE2
     FLAG
     NO_ARGS

Misuses
You should be aware of the issues relating to using constant subroutines in Perl. For example this:

  $r->custom_response(FORBIDDEN => "File size exceeds quota.");

will not set a custom response for "FORBIDDEN", but for the string "FORBIDDEN", which clearly isn't what is expected. You'll get an error like this:

  [Tue Apr 23 19:46:14 2002] null: Argument "FORBIDDEN" isn't
  numeric in subroutine entry at ...

Therefore, the best solution is not to use the hash notation for things that don't require it:

  $r->custom_response(FORBIDDEN,  "File size exceeds quota.");

Another important note is that instead of using HTTP codes, you should use designed for that purpose constants. Therefore, this is wrong:

  sub handler { return 200; }

The correct use is:

  use Apache::Constants qw(OK);
  sub handler { return OK; }

Also remember that "OK != HTTP_OK".

AUTHORS
Doug MacEachern, Gisle Aas and h2xs