*{"${app_package}::dispatch"} = sub {
$app_package->_setup_dispatcher(@_);
};
- *{"${app_package}::filter_response"} = sub (&) {
+ *{"${app_package}::response_filter"} = sub (&) {
$app_package->_construct_response_filter($_[0]);
};
*{"${app_package}::redispatch_to"} = sub {
$app_package->_construct_redispatch($_[0]);
};
+ *{"${app_package}::subdispatch"} = sub ($) {
+ $app_package->_construct_subdispatch($_[0]);
+ };
*{"${app_package}::default_config"} = sub {
$app_package->_setup_default_config(@_);
};
=head1 WHY?
-While I originally wrote Web::Simple as part of my Antiquated Perl talk for
-Italian Perl Workshop 2009, I've found that having a bare minimum system for
-writing web applications that doesn't drive me insane is rather nice.
+Web::Simple was originally written to form part of my Antiquated Perl talk for
+Italian Perl Workshop 2009, but in writing the bloggery example I realised
+that having a bare minimum system for writing web applications that doesn't
+drive me insane was rather nice and decided to spend my attempt at nanowrimo
+for 2009 improving and documenting it to the point where others could use it.
The philosophy of Web::Simple is to keep to an absolute bare minimum, for
everything. It is not designed to be used for large scale applications;
dispatch [ sub (...) { ... }, ... ];
- filter_response { ... };
+ response_filter { ... };
redispatch_to '/somewhere';
+ subdispatch sub (...) { ... }
+
and creates a $self global variable in your application package, so you can
use $self in dispatch subs without violating strict (Web::Simple::Application
arranges for dispatch subroutines to have the correct $self in scope when
application's dispatcher from these subs. The prototype of the subroutine
is expected to be a Web::Simple dispatch specification (see
L</DISPATCH SPECIFICATIONS> below for more details), and the body of the
-subroutine is the code to execute if the specification matches. See
-L</DISPATCH STRATEGY> below for details on how the Web::Simple dispatch
+subroutine is the code to execute if the specification matches.
+
+Each dispatcher is given the dispatcher constructed from the next element
+of the arrayref as its next dispatcher, except for the final element, which
+is given the return value of NameOfApplication->_build_final_dispatcher
+as its next dispatcher (by default this returns a 500 error response).
+
+See L</DISPATCH STRATEGY> below for details on how the Web::Simple dispatch
system uses the return values of these subroutines to determine how to
continue, alter or abort dispatch.
'/other/url', the dispatch behaviour will be exactly as if the same POST
request had been made to '/other/url' instead.
+=head2 subdispatch
+
+ subdispatch sub (/user/*/) {
+ my $u = $self->user($_[1]);
+ [
+ sub (GET) { $u },
+ sub (DELETE) { $u->delete },
+ ]
+ }
+
+The subdispatch subroutine is designed for use in dispatcher construction.
+
+It creates a dispatcher which, if it matches, treats its return value not
+as a final value but an arrayref of dispatch specifications such as could
+be passed to the dispatch subroutine itself. These are turned into a dispatcher
+which is then invoked. Any changes the match makes to the request are in
+scope for this inner dispatcher only - so if the initial match is a
+destructive one like .html the full path will be restored if the
+subdispatch fails.
+
=head1 DISPATCH STRATEGY
=head2 Description of the dispatcher object
to match an arbitrary number of parts up to but not including some final
part.
+Finally,
+
+ sub (/foo/...) {
+
+will match /foo/ on the beginning of the path -and- strip it, much like
+.html strips the extension. This is designed to be used to construct
+nested dispatch structures, but can also prove useful for having e.g. an
+optional language specification at the start of a path.
+
+Note that the '...' is a "maybe something here, maybe not" so the above
+specification will match like this:
+
+ /foo # no match
+ /foo/ # match and strip path to '/'
+ /foo/bar/baz # match and strip path to '/bar/baz'
+
=head3 Extension matches
sub (.html) {
returns something, of course). This is normally used for rendering - e.g.
sub (.html) {
- filter_response { $self->render_html($_[1]) }
+ response_filter { $self->render_html($_[1]) }
}
+Additionally,
+
+ sub (.*) {
+
+will match any extension and supplies the stripped extension as a match
+argument.
+
+=head3 Query and body parameter matches
+
+Query and body parameters can be match via
+
+ sub (?<param spec>) { # match URI query
+ sub (%<param spec>) { # match body params
+
+The body is only matched if the content type is
+application/x-www-form-urlencoded (note this means that Web::Simple does
+not yet handle uploads; this will be addressed in a later release).
+
+The param spec is elements of one of the following forms -
+
+ param~ # optional parameter
+ param= # required parameter
+ @param~ # optional multiple parameter
+ @param= # required multiple parameter
+ * # include all other parameters
+ @* # include all other parameters as multiple
+
+separated by the & character.
+
+So, to match a page parameter with an optional order_by parameter one
+would write:
+
+ sub (?page=&order_by~) {
+
+Parameters selected are turned into a hashref; in the case of singular
+parameters then if multiple values are found the last one is used. In the
+case of multiple parameters an arrayref of all values (or an empty arrayref
+for a missing optional) is used. The resulting hashref is provided as a
+match argument. So we might write something like:
+
+ sub (?page=&order_by~) {
+ my ($self, $p) = @_;
+ return unless $p->{page} =~ /^\d+$/;
+ $p->{order_by} ||= 'id';
+ response_filter {
+ $_[1]->search_rs({}, $p);
+ }
+ }
+
+to implement paging and ordering against a L<DBIx::Class::ResultSet> object.
+
=head3 Combining matches
Matches may be combined with the + character - e.g.
- sub (GET+/user/*) {
+ sub (GET + /user/*) {
+
+to create an AND match. They may also be combined withe the | character - e.g.
+
+ sub (GET|POST) {
+
+to create an OR match. Matches can be nested with () - e.g.
+
+ sub ((GET|POST) + /user/*) {
+
+and negated with ! - e.g.
+
+ sub (!/user/foo + /user/*) {
+
+! binds to the immediate rightmost match specification, so if you want
+to negate a combination you will need to use
+
+ sub ( !(POST|PUT|DELETE) ) {
+
+and | binds tighter than +, so
+
+ sub ((GET|POST) + /user/*) {
+
+and
+
+ sub (GET|POST + /user/*) {
+
+are equivalent, but
+
+ sub ((GET + .html) | (POST + .html)) {
+
+and
+
+ sub (GET + .html | POST + .html) {
+
+are not - the latter is equivalent to
+
+ sub (GET + (.html|POST) + .html) {
+
+which will never match.
+
+=head3 Whitespace
Note that for legibility you are permitted to use whitespace -
sub (GET + /user/*) {
-but it will be ignored.
+but it will be ignored. This is because the perl parser strips whitespace
+from subroutine prototypes, so this is equivalent to
+
+ sub (GET+/user/*) {
=cut
projects / catagits/Web-Simple.git / blobdiff