package Dancer; use strict; use warnings; use Carp 'confess'; use vars qw($VERSION $AUTHORITY @EXPORT); use Dancer::Config 'setting'; use Dancer::FileUtils; use Dancer::GetOpt; use Dancer::Error; use Dancer::Exceptions; use Dancer::Helpers; use Dancer::Logger; use Dancer::Renderer; use Dancer::Response; use Dancer::Route; use Dancer::Session; use Dancer::SharedData; use Dancer::Handler; use base 'Exporter'; $AUTHORITY = 'SUKRIA'; $VERSION = '1.140'; @EXPORT = qw( any before cookies content_type dance debug del dirname error false get header headers layout load logger mime_type options params pass path post prefix put r redirect request send_file send_error set set_cookie session splat status template true var vars warning ); # Dancer's syntax sub any { Dancer::Route->add_any(@_) } sub before { Dancer::Route->before_filter(@_) } sub cookies { Dancer::Cookies->cookies } sub content_type { Dancer::Response::content_type(@_) } sub debug { Dancer::Logger->debug(@_) } sub dirname { Dancer::FileUtils::dirname(@_) } sub error { Dancer::Logger->error(@_) } sub send_error { Dancer::Helpers->error(@_) } sub false {0} sub get { Dancer::Route->add('head', @_); Dancer::Route->add('get', @_); } sub headers { Dancer::Response::headers(@_); } sub header { goto &headers; } # goto ftw! sub layout { set(layout => shift) } sub logger { set(logger => @_) } sub load { require $_ for @_ } sub mime_type { Dancer::Config::mime_types(@_) } sub params { Dancer::SharedData->request->params(@_) } sub pass {pass_exception} sub path { Dancer::FileUtils::path(@_) } sub post { Dancer::Route->add('post', @_) } sub prefix { Dancer::Route->prefix(@_) } sub del { Dancer::Route->add('delete', @_) } sub options { Dancer::Route->add('options', @_) } sub put { Dancer::Route->add('put', @_) } sub r { {regexp => $_[0]} } sub redirect { Dancer::Helpers::redirect(@_) } sub request { Dancer::SharedData->request } sub send_file { Dancer::Helpers::send_file(@_) } sub set { setting(@_) } sub set_cookie { Dancer::Helpers::set_cookie(@_) } sub session { if (@_ == 0) { return Dancer::Session->get; } else { return (@_ == 1) ? Dancer::Session->read(@_) : Dancer::Session->write(@_); } } sub splat { @{Dancer::SharedData->request->params->{splat}} } sub status { Dancer::Response::status(@_) } sub template { Dancer::Helpers::template(@_) } sub true {1} sub var { Dancer::SharedData->var(@_) } sub vars { Dancer::SharedData->vars } sub warning { Dancer::Logger->warning(@_) } # When importing the package, strict and warnings pragma are loaded, # and the appdir detection is performed. sub import { my ($class, $symbol) = @_; my ($package, $script) = caller; strict->import; warnings->import; $class->export_to_level(1, $class, @EXPORT); # if :syntax option exists, don't change settings if ($symbol && $symbol eq ':syntax') { return; } setting appdir => dirname(File::Spec->rel2abs($script)); setting public => path(setting('appdir'), 'public'); setting views => path(setting('appdir'), 'views'); setting logger => 'file'; } # Start/Run the application with the chosen apphandler sub dance { my ($class, $request) = @_; Dancer::Config->load; Dancer::Handler->get_handler()->dance($request); } 1; __END__ =pod =head1 NAME Dancer =head1 DESCRIPTION Dancer is a web application framework designed to be as effortless as possible for the developer. Dancer is here to provide the simpliest way for writing a web application. It can be use to write light-weight web services or small standalone web applications. If you don't want to write a CGI by hand and find Catalyst too big for your project, Dancer is what you need. =head1 USAGE As soon as Dancer is imported to a script, that script becomes a webapp. All the script has to do is to declare a list of B<routes>. A route handler is composed by an HTTP method, a path pattern and a code block. The code block given to the route handler has to return a string which will be used as the content to render to the client. Routes are defined for a given HTTP method. For each method supported, a keyword is exported by the module. Here is an example of a route definition: get '/hello/:name' => sub { # do something important here return "Hello ".params->{name}; }; The route is defined for the method 'get', so only GET requests will be honoured by that route. =head2 HTTP METHODS All existing HTTP methods are defined in the RFC 2616 L<http://www.w3.org/Protocols/rfc2616/rfc2616-sec9.html>. Here are the ones you can use to define your route handlers. =over 8 =item B<GET> The GET method retrieves information (when defining a route handler for the GET method, Dancer automatically defines a route handler for the HEAD method, in order to honour HEAD requests for each of your GET route handlers). To define a GET action, use the B<get> keyword. =item B<POST> The POST method is used to create a ressource on the server. To define a POST action, use the B<post> keyword. =item B<PUT> The PUT method is used to update an existing ressource. To define a PUT action, use the B<put> keyword. =item B<DELETE> The DELETE method requests that the origin server delete the resource identified by the Request-URI. To define a DELETE action, use the B<del> keyword. =back You can also use the special keyword B<any> to define a route for multiple methods at once. For instance, you may want to define a route for both GET and POST methods, this is done like the following: any ['get', 'post'] => '/myaction' => sub { # code }; Or even, a route handler that would match any HTTP methods: any '/myaction' => sub { # code }; =head2 ROUTE HANDLERS The route action is the code reference declared, it can access parameters through the `params' keyword, which returns a hashref. This hashref is a merge of the route pattern matches and the request params. You can have more details about how params are built and how to access them in the L<Dancer::Request> documentation. =head2 NAMED MATCHING A route pattern can contain one or more tokens (a word prefixed with ':'). Each token found in a route pattern is used as a named-pattern match. Any match will be set in the params hashref. get '/hello/:name' => sub { "Hey ".params->{name}.", welcome here!"; }; =head2 WILDCARDS MATCHING A route can contain a wildcard (represented by a '*'). Each wildcard match will be returned in an arrayref, accessible via the `splat' keyword. get '/download/*.* => sub { my ($file, $ext) = splat; # do something with $file.$ext here }; =head2 REGULAR EXPRESSION MATCHING A route can be defined with a Perl regular expression. The syntax is assumed to be a classic Perl regexp except for the slashes that will be escaped before running the match. For instance, don't do '\/hello\/(.+)' but rather: '/hello/(.+)' In order to tell Dancer to consider the route as a real regexp, the route must be defined explicitly with the keyword 'r', like the following: get r( '/hello/([\w]+)' ) => sub { my ($name) = splat; return "Hello $name"; }; =head2 CONDITIONAL MATCHING Routes may include some matching conditions (on the useragent and the hostname at the moment): get '/foo', {agent => 'Songbird (\d\.\d)[\d\/]*?'} => sub { 'foo method for songbird' } get '/foo' => sub { 'all browsers except songbird' } =head2 PREFIX A prefix can be defined for each route handler, like this: prefix '/home'; From here, any route handler is defined to /home/* get '/page1' => sub {}; # will match '/home/page1' You can unset the prefix value prefix undef; get '/page1' => sub {}; will match /page1 =head2 RUNNING THE WEBSERVER Once the script is ready, you can run the webserver just by running the script. The following options are supported: =over 8 =item B<--port=XXXX> set the port to listen to (default is 3000) =item B<--daemon> run the webserver in the background =item B<--help> display a detailed help message =back =head1 ACTION SKIPPING An action can choose not to serve the current request and ask Dancer to process the request with the next matching route. This is done with the B<pass> keyword, like in the following example get '/say/:word' => sub { pass if (params->{word} =~ /^\d+$/); "I say a word: ".params->{word}; }; get '/say/:number' => sub { "I say a number: ".params->{number}; }; =head1 ACTION RESPONSES The action's return value is always considered to be the content to render. So take care to your return value. In order to change the default behaviour of the rendering of an action, you can use the following keywords. =head2 redirect The redirect action is a helper and shortcut to a common HTTP response code (302). You can either redirect to a complete different site or you can also do it within the application: get '/twitter', sub { redirect 'http://twitter.com/me'; }; You can also force Dancer to return an specific 300-ish HTTP response code: get '/old/:resouce', sub { redirect '/new/'.params->{resource}, 301; }; =head2 status By default, an action will produce an 'HTTP 200 OK' status code, meaning everything is OK. It's possible to change that with the keyword B<status> : get '/download/:file' => { if (! -f params->{file}) { status 'not_found'; return "File does not exist, unable to download"; } # serving the file... }; In that example, Dancer will notice that the status has changed, and will render the response accordingly. The status keyword receives the name of the status to render, it can be either an HTTP code or its alias, as defined in L<Dancer::HTTP>. =head2 content_type You can also change the content type rendered in the same maner, with the keyword B<content_type> get '/cat/:txtfile' => { content_type 'text/plain'; # here we can dump the contents of params->{txtfile} }; =head2 header(s) It is possible to add custom headers to responses with the B<header> (or B<headers>) keyword: get '/send/header', sub { header 'X-My-Header' => 'shazam!'; } or... get '/send/headers', sub { headers 'X-Foo' => 'bar', X-Bar => 'foo'; } You can use both undistinctly, they do exactly what you expect them to do. =head1 ERROR HANDLING =head2 DEFAULT ERROR PAGES When an error is renderered (the action responded with a status code different than 200), Dancer first looks in the public directory for an HTML file matching the error code (eg: 500.html or 404.html). If such a file exists, it's used to render the error, otherwise, a default error page will be rendered on the fly. =head2 EXECUTION ERRORS When an error occurs during the route execution, Dancer will render an error page with the HTTP status code 500. It's possible either to display the content of the error message or to hide it with a generic error page. This is a choice left to the end-user and can be set with the B<show_errors> setting. Note that you can also choose to consider all warnings in your route handlers as errors when the setting B<warnings> is set to 1. =head1 FILTERS =head2 Before filters Before filters are evaluated before each request within the context of the request and can modify the request and response. It's possible to define variable that will be accessible in the action blocks with the keyword 'var'. before sub { var note => 'Hi there'; request->path('/foo/oversee') }; get '/foo/*' => sub { my ($match) = splat; # 'oversee'; vars->{note}; # 'Hi there' }; The request keyword returns the current Dancer::Request object representing the incoming request. See the documentation of the L<Dancer::Request> module for details. =head1 CONFIGURATION AND ENVIRONMENTS Configuring a Dancer application can be done in many ways. The easiest one (and maybe the the dirtiest) is to put all your settings statements at the top of your script, before calling the dance() method. Other ways are possible, you can write all your setting calls in the file `appdir/config.yml'. For this, you must have installed the YAML module, and of course, write the conffile in YAML. That's better than the first option, but it's still not perfect as you can't switch easily from an environment to another without rewriting the config.yml file. The better way is to have one config.yml file with default global settings, like the following: # appdir/config.yml logger: 'file' layout: 'main' And then write as many environment file as you like in appdir/environements. That way, the good environment config file will be loaded according to the running environment (if none specified, it will be 'development'). Note that you can change the running environment using the --environment commandline switch. Typically, you'll want to set the following values in a development config file: # appdir/environments/development.yml log: 'debug' access_log: 1 And in a production one: # appdir/environments/production.yml log: 'warning' access_log: 0 =head2 load You can use the load method to include additional routes into your application: get '/go/:value', sub { # foo }; load 'more_routes.pl'; # then, in the file more_routes.pl: get '/yes', sub { 'orly?'; }; B<load> is just a wrapper for B<require>, but you can also specify a list of routes files: load 'login_routes.pl', 'session_routes.pl', 'misc_routes.pl'; =head1 importing just the syntax If you want to use more complex files hierarchies, you can import just the syntax of Dancer. package App; use Dancer; # App may contain generic routes use App::User::Routes; # user-related routes Then in App/User/Routes.pm: use Dancer ':syntax'; get '/user/view/:id' => sub { ... }; =head1 LOGGING It's possible to log messages sent by the application. In the current version, only one method is possible for logging messages but it may come in future releases new methods. In order to enable the logging system for your application, you first have to start the logger engine in your config.yml log: 'file' Then you can choose which kind of messages you want to actually log: log: 'debug' # will log debug, warning and errors log: 'warning' # will log warning and errors log: 'error' # will log only errors A directory appdir/logs will be created and will host one logfile per environment. The log message contains the time it was written, the PID of the current process, the message and the caller information (file and line). =head1 USING TEMPLATES =head1 VIEWS It's possible to render the action's content with a template, this is called a view. The `appdir/views' directory is the place where views are located. You can change this location by changing the setting 'views', for instance if your templates are located in the 'templates' directory, do the following: set views => path(dirname(__FILE__), 'templates'); By default, the internal template engine is used (L<Dancer::Template::Simple>) but you may want to upgrade to Template::Toolkit. If you do so, you have to enable this engine in your settings as explained in L<Dancer::Template::TemplateToolkit>. If you do so, you'll also have to import the L<Template> module in your application code. Note that Dancer configures the Template::Toolkit engine to use <% %> brackets instead of its default [% %] brackets. All views must have a '.tt' extension. This may change in the future. In order to render a view, just call the 'template' keyword at the end of the action by giving the view name and the HASHREF of tokens to interpolate in the view (note that all the route params are accessible in the view): use Dancer; use Template; get '/hello/:name' => sub { template 'hello' => {var => 42}; }; And the appdir/views/hello.tt view can contain the following code: <html> <head></head> <body> <h1>Hello <% params.name %></h1> </body> </html> =head2 LAYOUTS A layout is a special view, located in the 'layouts' directory (inside the views directory) which must have a token named `content'. That token marks the place where to render the action view. This lets you define a global layout for your actions. Here is an example of a layout: views/layouts/main.tt : <html> <head>...</head> <body> <div id="header"> ... </div> <div id="content"> <% content %> </div> </body> </html> This layout can be used like the following: use Dancer; use Template; layout 'main'; get '/' => sub { template 'index'; }; =head1 STATIC FILES =head2 STATIC DIRECTORY Static files are served from the ./public directory. You can specify a different location by setting the 'public' option: set public => path(dirname(__FILE__), 'static'); Note that the public directory name is not included in the URL. A file ./public/css/style.css is made available as example.com/css/style.css. =head2 MIME-TYPES CONFIGURATION By default, Dancer will automatically detect the mime-types to use for the static files accessed. It's possible to choose specific mime-type per file extensions. For instance, we can imagine you want to sever *.foo as a text/foo content, instead of text/plain (which would be the content type detected by Dancer if *.foo are text files). mime_type foo => 'text/foo'; This configures the 'text/foo' content type for any file matching '*.foo'. =head2 STATIC FILE FROM A ROUTE HANDLER It's possible for a route handler to pass the batton to a static file, like the following. get '/download/*' => sub { my $params = shift; my ($file) = @{ $params->{splat} }; send_file $file; }; Or even if you want your index page to be a plain old index.html file, just do: get '/' => sub { send_file '/index.html' }; =head1 SETTINGS It's possible to change quite every parameter of the application via the settings mechanism. A setting is key/value pair assigned by the keyword B<set>: set setting_name => 'setting_value'; See L<Dancer::Config> for complete details about supported settings. =head1 EXAMPLE This is a possible webapp created with Dancer : #!/usr/bin/perl # make this script a webapp use Dancer; # declare routes/actions get '/' => sub { "Hello World"; }; get '/hello/:name' => sub { "Hello ".params->{name}" }; # run the webserver Dancer->dance; =head1 AUTHOR This module has been written by Alexis Sukrieh <sukria@cpan.org> and others, see the AUTHORS file that comes with this distribution for details. =head1 SOURCE CODE The source code for this module is hosted on GitHub L<http://github.com/sukria/Dancer> =head1 DEPENDENCIES Dancer depends on the following modules: The following modules are mandatory (Dancer cannot run without them) =over 8 =item L<HTTP::Server::Simple::PSGI> =item L<Exception::Class> =item L<HTTP::Body> =back The following modules are optional =over 8 =item L<Template> : In order to use TT for rendering views =item L<YAML> : needed for configuration file support =item L<File::MimeInfo::Simple> =back =head1 LICENSE This module is free software and is published under the same terms as Perl itself. =head1 SEE ALSO The concept behind this module comes from the Sinatra ruby project, see L<http://www.sinatrarb.com> for details. =cut