Building a web service with Perl - web-services

Question

I need to build a server-side application (tiny web service) for testing proposes. What are some CPAN modules and Perl libraries for implementing such task?

Answer 1

Testing a tiny Web service with Plack::Test:
use Plack::Test;
use Test::More;
test_psgi(
app => sub {
my ($env) = #_;
return [200, ['Content-Type' => 'text/plain'], ["Hello World"]],
},
client => sub {
my ($cb) = #_;
my $req = HTTP::Request->new(GET => "http://localhost/hello");
my $res = $cb->($req);
like $res->content, qr/Hello World/;
},
);
done_testing;

Answer 2

There are a lot of possibilities
CGI - if you like to do everything like in the olden days
CGI::Application - a little more advanced
or you could use frameworks like
Catalyst
Dancer
Mojolicious
It depends on your skills and aims what solution you should choose.

Answer 3

A web service simply returns a HTTP status code and some data, perhaps serialized in JSON or XML. You can use the CGI module to do this, e.g.:
#!/usr/bin/perl -w
use strict;
use warnings;
use CGI;
use CGI::Pretty qw/:standard/;
use URI::Escape;
my $query = CGI->new;
my $jsonQueryValue = uri_unescape $query->param('helloWorld');
# let's say that 'helloWorld' is a uri_escape()-ed POST variable
# that contains the JSON object { 'hello' : 'world' }
print header(-type => "application/json", -status => "200 OK");
print "$jsonQueryValue";
You can, of course, print an HTTP response with other status codes and data. A web service might need to return a 404 error, for example, depending on what's being asked for. That sort of thing.

Answer 4

I like to use mojolicious. It's lightweight at first and can do the heavy lifting later too. Mojolicious::Lite in particular is good for quick and dirty.
use Mojolicious::Lite;
# Route with placeholder
get '/:foo' => sub {
my $self = shift;
my $foo = $self->param('foo');
$self->render(text => "Hello from $foo.");
};
# Start the Mojolicious command system
app->start;