NAME

       ModPerl::RegistryCooker - Cook mod_perl 2.0 Registry Modules

Synopsis

         # shouldn't be used as-is but sub-classed first
         # see ModPerl::Registry for an example

Description

       "ModPerl::RegistryCooker" is used to create flexible and overridable registry modules
       which emulate mod_cgi for Perl scripts. The concepts are discussed in the manpage of the
       following modules: "ModPerl::Registry", "ModPerl::Registry" and "ModPerl::RegistryBB".

       "ModPerl::RegistryCooker" has two purposes:

       •   Provide ingredients that can be used by registry sub-classes

       •   Provide a default behavior, which can be overridden in sub-classed

           META: in the future this functionality may move into a separate class.

       Here are the current overridable methods:

       META: these are all documented in RegistryCooker.pm, though not using pod. please help to
       port these to pod and move the descriptions here.

       •   new()

           create the class's object, bless it and return it

             my $obj = $class->new($r);

           $class -- the registry class, usually "__PACKAGE__" can be used.

           $r -- "Apache2::Request" object.

           default: new()

       •   init()

           initializes the data object's fields: "REQ", "FILENAME", "URI". Called from the new().

           default: init()

       •   default_handler()

           default:  default_handler()

       •   run()

           default: run()

       •   can_compile()

           default: can_compile()

       •   make_namespace()

           default: make_namespace()

       •   namespace_root()

           default: namespace_root()

       •   namespace_from()

           If "namespace_from_uri" is used and the script is called from the virtual host, by
           default the virtual host name is prepended to the uri when package name for the
           compiled script is created. Sometimes this behavior is undesirable, e.g., when the
           same (physical) script is accessed using the same path_info but different virtual
           hosts. In that case you can make the script compiled only once for all vhosts, by
           specifying:

             $ModPerl::RegistryCooker::NameWithVirtualHost = 0;

           The drawback is that it affects the global environment and all other scripts will be
           compiled ignoring virtual hosts.

           default: namespace_from()

       •   is_cached()

           default: is_cached()

       •   should_compile()

           default: should_compile()

       •   flush_namespace()

           default: flush_namespace()

       •   cache_table()

           default: cache_table()

       •   cache_it()

           default: cache_it()

       •   read_script()

           default: read_script()

       •   shebang_to_perl()

           default: shebang_to_perl()

       •   get_script_name()

           default: get_script_name()

       •   chdir_file()

           default: chdir_file()

       •   get_mark_line()

           default: get_mark_line()

       •   compile()

           default: compile()

       •   error_check()

           default: error_check()

       •   strip_end_data_segment()

           default: strip_end_data_segment()

       •   convert_script_to_compiled_handler()

           default: convert_script_to_compiled_handler()

   Special Predefined Functions
       The following functions are implemented as constants.

       •   NOP()

           Use when the function shouldn't do anything.

       •   TRUE()

           Use when a function should always return a true value.

       •   FALSE()

           Use when a function should always return a false value.

Sub-classing Techniques

       To override the default "ModPerl::RegistryCooker" methods, first, sub-class
       "ModPerl::RegistryCooker" or one of its existing sub-classes, using "use base". Second,
       override the methods.

       Those methods that weren't overridden will be resolved at run time when used for the first
       time and cached for the future requests. One way to to shortcut this first run resolution
       is to use the symbol aliasing feature. For example to alias
       "ModPerl::MyRegistry::flush_namespace" as "ModPerl::RegistryCooker::flush_namespace", you
       can do:

         package ModPerl::MyRegistry;
         use base qw(ModPerl::RegistryCooker);
         *ModPerl::MyRegistry::flush_namespace =
             \&ModPerl::RegistryCooker::flush_namespace;
         1;

       In fact, it's a good idea to explicitly alias all the methods so you know exactly what
       functions are used, rather then relying on the defaults. For that purpose
       "ModPerl::RegistryCooker" class method install_aliases() can be used. Simply prepare a
       hash with method names in the current package as keys and corresponding fully qualified
       methods to be aliased for as values and pass it to install_aliases(). Continuing our
       example we could do:

         package ModPerl::MyRegistry;
         use base qw(ModPerl::RegistryCooker);
         my %aliases = (
             flush_namespace => 'ModPerl::RegistryCooker::flush_namespace',
         );
         __PACKAGE__->install_aliases(\%aliases);
         1;

       The values use fully qualified packages so you can mix methods from different classes.

Examples

       The best examples are existing core registry modules: "ModPerl::Registry",
       "ModPerl::Registry" and "ModPerl::RegistryBB". Look at the source code and their manpages
       to see how they subclass "ModPerl::RegistryCooker".

       For example by default "ModPerl::Registry" uses the script's path when creating a
       package's namespace. If for example you want to use a uri instead you can override it
       with:

         *ModPerl::MyRegistry::namespace_from =
             \&ModPerl::RegistryCooker::namespace_from_uri;
         1;

       Since the "namespace_from_uri" component already exists in "ModPerl::RegistryCooker". If
       you want to write your own method, e.g., that creates a namespace based on the inode, you
       can do:

         sub namespace_from_inode {
             my $self = shift;
             return (stat $self->[FILENAME])[1];
         }

       META: when $r->finfo will be ported it'll be more effecient.  (stat $r->finfo)[1]

Authors

       Doug MacEachern

       Stas Bekman

See Also

       "ModPerl::Registry", "ModPerl::RegistryBB" and "ModPerl::PerlRun".

perl v5.26.1                 libapache2-mod-perl2-2.0.10::docs::api::ModPerl::RegistryCooker(3pm)