focal (3) Mojolicious::Plugin::DefaultHelpers.3pm.gz
NAME
Mojolicious::Plugin::DefaultHelpers - Default helpers plugin
SYNOPSIS
# Mojolicious
$app->plugin('DefaultHelpers');
# Mojolicious::Lite
plugin 'DefaultHelpers';
DESCRIPTION
Mojolicious::Plugin::DefaultHelpers is a collection of helpers for Mojolicious.
This is a core plugin, that means it is always enabled and its code a good example for learning to build
new plugins, you're welcome to fork it.
See "PLUGINS" in Mojolicious::Plugins for a list of plugins that are available by default.
HELPERS
Mojolicious::Plugin::DefaultHelpers implements the following helpers.
accepts
my $formats = $c->accepts;
my $format = $c->accepts('html', 'json', 'txt');
Select best possible representation for resource from "format" "GET"/"POST" parameter, "format" stash
value or "Accept" request header with "accepts" in Mojolicious::Renderer, defaults to returning the first
extension if no preference could be detected.
# Check if JSON is acceptable
$c->render(json => {hello => 'world'}) if $c->accepts('json');
# Check if JSON was specifically requested
$c->render(json => {hello => 'world'}) if $c->accepts('', 'json');
# Unsupported representation
$c->render(data => '', status => 204)
unless my $format = $c->accepts('html', 'json');
# Detected representations to select from
my @formats = @{$c->accepts};
app
%= app->secrets->[0]
Alias for "app" in Mojolicious::Controller.
b
%= b('Joel is a slug')->slugify
Turn string into a Mojo::ByteStream object.
c
%= c('a', 'b', 'c')->shuffle->join
Turn list into a Mojo::Collection object.
config
%= config 'something'
Alias for "config" in Mojolicious.
content
%= content foo => begin
test
% end
%= content bar => 'Hello World!'
%= content 'foo'
%= content 'bar'
%= content
Store partial rendered content in a named buffer and retrieve it later, defaults to retrieving the named
buffer "content", which is used by the renderer for the "layout" and "extends" features. New content will
be ignored if the named buffer is already in use.
content_for
% content_for foo => begin
test
% end
%= content_for 'foo'
Same as "content", but appends content to named buffers if they are already in use.
% content_for message => begin
Hello
% end
% content_for message => begin
world!
% end
%= content 'message'
content_with
% content_with foo => begin
test
% end
%= content_with 'foo'
Same as "content", but replaces content of named buffers if they are already in use.
% content message => begin
world!
% end
% content_with message => begin
Hello <%= content 'message' %>
% end
%= content 'message'
continue
$c->continue;
Continue dispatch chain from an intermediate destination with "continue" in Mojolicious::Routes.
csrf_token
%= csrf_token
Get CSRF token from "session", and generate one if none exists.
current_route
% if (current_route 'login') {
Welcome to Mojolicious!
% }
%= current_route
Check or get name of current route.
dumper
%= dumper {some => 'data'}
Dump a Perl data structure with "dumper" in Mojo::Util, very useful for debugging.
extends
% extends 'blue';
% extends 'blue', title => 'Blue!';
Set "extends" stash value, all additional key/value pairs get merged into the "stash".
flash
my $foo = $c->flash('foo');
$c = $c->flash({foo => 'bar'});
$c = $c->flash(foo => 'bar');
%= flash 'foo'
Data storage persistent only for the next request, stored in the "session".
# Show message after redirect
$c->flash(message => 'User created successfully!');
$c->redirect_to('show_user', id => 23);
inactivity_timeout
$c = $c->inactivity_timeout(3600);
Use "stream" in Mojo::IOLoop to find the current connection and increase timeout if possible.
# Longer version
Mojo::IOLoop->stream($c->tx->connection)->timeout(3600);
include
%= include 'menubar'
%= include 'menubar', format => 'txt'
Alias for "render_to_string" in Mojolicious::Controller.
is_fresh
my $bool = $c->is_fresh;
my $bool = $c->is_fresh(etag => 'abc');
my $bool = $c->is_fresh(etag => 'W/"def"');
my $bool = $c->is_fresh(last_modified => $epoch);
Check freshness of request by comparing the "If-None-Match" and "If-Modified-Since" request headers to
the "ETag" and "Last-Modified" response headers with "is_fresh" in Mojolicious::Static.
# Add ETag/Last-Modified headers and check freshness before rendering
$c->is_fresh(etag => 'abc', last_modified => 1424985708)
? $c->rendered(304)
: $c->render(text => 'I ♥ Mojolicious!');
layout
% layout 'green';
% layout 'green', title => 'Green!';
Set "layout" stash value, all additional key/value pairs get merged into the "stash".
log
my $log = $c->log;
Alternative to "log" in Mojolicious that includes "request_id" in Mojo::Message::Request with every log
message.
# Log message with context
$c->log->debug('This is a log message with request id');
# Pass logger with context to model
my $log = $c->log;
$c->some_model->create({foo => $foo}, $log);
param
%= param 'foo'
Alias for "param" in Mojolicious::Controller.
proxy->get_p
my $promise = $c->proxy->get_p('http://example.com' => {Accept => '*/*'});
Perform non-blocking "GET" request and forward response as efficiently as possible, takes the same
arguments as "get" in Mojo::UserAgent and returns a Mojo::Promise object. Note that this helper is
EXPERIMENTAL and might change without warning!
# Forward with exception handling
$c->proxy->get_p('http://mojolicious.org')->catch(sub {
my $err = shift;
$c->log->debug("Proxy error: $err");
$c->render(text => 'Something went wrong!', status => 400);
});
proxy->post_p
my $promise = $c->proxy->post_p('http://example.com' => {Accept => '*/*'});
Perform non-blocking "POST" request and forward response as efficiently as possible, takes the same
arguments as "post" in Mojo::UserAgent and returns a Mojo::Promise object. Note that this helper is
EXPERIMENTAL and might change without warning!
# Forward with exception handling
$c->proxy->post_p('example.com' => form => {test => 'pass'})->catch(sub {
my $err = shift;
$c->log->debug("Proxy error: $err");
$c->render(text => 'Something went wrong!', status => 400);
});
proxy->start_p
my $promise = $c->proxy->start_p(Mojo::Transaction::HTTP->new);
Perform non-blocking request for a custom Mojo::Transaction::HTTP object and forward response as
efficiently as possible, returns a Mojo::Promise object. Note that this helper is EXPERIMENTAL and might
change without warning!
# Forward with exception handling
my $tx = $c->ua->build_tx(GET => 'http://mojolicious.org');
$c->proxy->start_p($tx)->catch(sub {
my $err = shift;
$c->log->debug("Proxy error: $err");
$c->render(text => 'Something went wrong!', status => 400);
});
# Forward with custom request and response headers
my $headers = $c->req->headers->clone->dehop;
$headers->header('X-Proxy' => 'Mojo');
my $tx = $c->ua->build_tx(GET => 'http://example.com' => $headers->to_hash);
$c->proxy->start_p($tx);
$tx->res->content->once(body => sub {
$c->res->headers->header('X-Proxy' => 'Mojo');
});
redirect_to
$c = $c->redirect_to('named', foo => 'bar');
$c = $c->redirect_to('named', {foo => 'bar'});
$c = $c->redirect_to('/index.html');
$c = $c->redirect_to('http://example.com/index.html');
Prepare a 302 (if the status code is not already "3xx") redirect response with "Location" header, takes
the same arguments as "url_for".
# Moved Permanently
$c->res->code(301);
$c->redirect_to('some_route');
# Temporary Redirect
$c->res->code(307);
$c->redirect_to('some_route');
reply->asset
$c->reply->asset(Mojo::Asset::File->new);
Reply with a Mojo::Asset::File or Mojo::Asset::Memory object using "serve_asset" in Mojolicious::Static,
and perform content negotiation with "Range", "If-Modified-Since" and "If-None-Match" headers.
# Serve asset with custom modification time
my $asset = Mojo::Asset::Memory->new;
$asset->add_chunk('Hello World!')->mtime(784111777);
$c->res->headers->content_type('text/plain');
$c->reply->asset($asset);
# Serve static file if it exists
if (my $asset = $c->app->static->file('images/logo.png')) {
$c->res->headers->content_type('image/png');
$c->reply->asset($asset);
}
reply->exception
$c = $c->reply->exception('Oops!');
$c = $c->reply->exception(Mojo::Exception->new);
Render the exception template "exception.$mode.$format.*" or "exception.$format.*" and set the response
status code to 500. Also sets the stash values "exception" to a Mojo::Exception object and "snapshot" to
a copy of the "stash" for use in the templates.
reply->file
$c->reply->file('/etc/passwd');
Reply with a static file from an absolute path anywhere on the file system using "static" in Mojolicious.
# Longer version
$c->reply->asset(Mojo::Asset::File->new(path => '/etc/passwd'));
# Serve file from an absolute path with a custom content type
$c->res->headers->content_type('application/myapp');
$c->reply->file('/home/sri/foo.txt');
# Serve file from a secret application directory
$c->reply->file($c->app->home->child('secret', 'file.txt'));
reply->not_found
$c = $c->reply->not_found;
Render the not found template "not_found.$mode.$format.*" or "not_found.$format.*" and set the response
status code to 404. Also sets the stash value "snapshot" to a copy of the "stash" for use in the
templates.
reply->static
my $bool = $c->reply->static('images/logo.png');
my $bool = $c->reply->static('../lib/MyApp.pm');
Reply with a static file using "static" in Mojolicious, usually from the "public" directories or "DATA"
sections of your application. Note that this helper uses a relative path, but does not protect from
traversing to parent directories.
# Serve file from a relative path with a custom content type
$c->res->headers->content_type('application/myapp');
$c->reply->static('foo.txt');
respond_to
$c = $c->respond_to(
json => {json => {message => 'Welcome!'}},
html => {template => 'welcome'},
any => sub {...}
);
Automatically select best possible representation for resource from "format" "GET"/"POST" parameter,
"format" stash value or "Accept" request header, defaults to "default_format" in Mojolicious::Renderer or
rendering an empty 204 response. Each representation can be handled with a callback or a hash reference
containing arguments to be passed to "render" in Mojolicious::Controller.
# Everything else than "json" and "xml" gets a 204 response
$c->respond_to(
json => sub { $c->render(json => {just => 'works'}) },
xml => {text => '<just>works</just>'},
any => {data => '', status => 204}
);
For more advanced negotiation logic you can also use "accepts".
session
%= session 'foo'
Alias for "session" in Mojolicious::Controller.
stash
%= stash 'foo'
% stash foo => 'bar';
Alias for "stash" in Mojolicious::Controller.
%= stash('name') // 'Somebody'
timing->begin
$c->timing->begin('foo');
Create named timestamp for "timing->elapsed".
timing->elapsed
my $elapsed = $c->timing->elapsed('foo');
Return fractional amount of time in seconds since named timstamp has been created with "timing->begin" or
"undef" if no such timestamp exists.
# Log timing information
$c->timing->begin('database_stuff');
...
my $elapsed = $c->timing->elapsed('database_stuff');
$c->app->log->debug("Database stuff took $elapsed seconds");
timing->rps
my $rps = $c->timing->rps('0.001');
Return fractional number of requests that could be performed in one second if every singe one took the
given amount of time in seconds or "undef" if the number is too low.
# Log more timing information
$c->timing->begin('web_stuff');
...
my $elapsed = $c->timing->elapsed('web_stuff');
my $rps = $c->timing->rps($elapsed);
$c->app->log->debug("Web stuff took $elapsed seconds ($rps per second)");
timing->server_timing
$c->timing->server_timing('metric');
$c->timing->server_timing('metric', 'Some Description');
$c->timing->server_timing('metric', 'Some Description', '0.001');
Create "Server-Timing" header with optional description and duration.
# "Server-Timing: miss"
$c->timing->server_timing('miss');
# "Server-Timing: dc;desc=atl"
$c->timing->server_timing('dc', 'atl');
# "Server-Timing: db;desc=Database;dur=0.0001"
$c->timing->begin('database_stuff');
...
my $elapsed = $c->timing->elapsed('database_stuff');
$c->timing->server_timing('db', 'Database', $elapsed);
# "Server-Timing: miss, dc;desc=atl"
$c->timing->server_timing('miss');
$c->timing->server_timing('dc', 'atl');
title
%= title
% title 'Welcome!';
% title 'Welcome!', foo => 'bar';
Get or set "title" stash value, all additional key/value pairs get merged into the "stash".
ua
%= ua->get('mojolicious.org')->result->dom->at('title')->text
Alias for "ua" in Mojolicious.
url_for
%= url_for 'named', controller => 'bar', action => 'baz'
Alias for "url_for" in Mojolicious::Controller.
%= url_for('/index.html')->query(foo => 'bar')
url_with
%= url_with 'named', controller => 'bar', action => 'baz'
Does the same as "url_for", but inherits query parameters from the current request.
%= url_with->query({page => 2})
validation
my $v = $c->validation;
Get Mojolicious::Validator::Validation object for current request to validate file uploads as well as
"GET" and "POST" parameters extracted from the query string and "application/x-www-form-urlencoded" or
"multipart/form-data" message body. Parts of the request body need to be loaded into memory to parse
"POST" parameters, so you have to make sure it is not excessively large. There's a 16MiB limit for
requests by default.
# Validate GET/POST parameter
my $v = $c->validation;
$v->required('title', 'trim')->size(3, 50);
my $title = $v->param('title');
# Validate file upload
my $v = $c->validation;
$v->required('tarball')->upload->size(1, 1048576);
my $tarball = $v->param('tarball');
METHODS
Mojolicious::Plugin::DefaultHelpers inherits all methods from Mojolicious::Plugin and implements the
following new ones.
register
$plugin->register(Mojolicious->new);
Register helpers in Mojolicious application.
SEE ALSO
Mojolicious, Mojolicious::Guides, <https://mojolicious.org>.