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Mojolicious - Can't parse JSON in RESTful


It's impossible to parse JSON in Mojolicious for me. I updated Mojolicious and used before following code, but JSON->new is deprecated.

my $json = Mojo::JSON->new;
my $user_request = $json->decode($c->req->body);
my $err = $json->error;

from the tutorials, I found out there has been added $self->req->json, but all POSTs to this will result into errors and non working code.

 curl -H "Content-Type: application/json" --data @body.json http://localhost:3000/checkaddress

and my body.json looks like this

{
       'id': 1
}

Here is my RESTful code in Mojolicious

post '/checkaddress' => sub {
my $self = shift;
my $dump = $self->dumper($self->req->json);
};

Console log

[Sat Feb 20 08:23:27 2016] [debug] 200 OK (0.001688s, 592.417/s)
[Sat Feb 20 08:24:38 2016] [debug] POST "/checkaddress"
[Sat Feb 20 08:24:38 2016] [debug] Routing to a callback
[Sat Feb 20 08:24:38 2016] [debug] undef

Calling $self->req->body and then decode_json from Mojo::JSON will result into

[error] Malformed JSON: Expected string while parsing object at line 1,  offset 5 at /home/aa/sempt2.pl line 15.

So, how to parse JSON correctly now?


Solution

  • This works with Mojolicious 6.25 and is a complete example:

    package MyREST;
    use Mojo::Base 'Mojolicious';
    
    use Data::Dumper;
    
    sub startup {
      my $app = shift;
    
      my $routes = $app->routes;
    
      $routes->post('/checkaddress' => sub {
        my $self = shift;
        my $data = $self->req->json;
        my $dump = $self->dumper($self->req->json);
        print STDERR $dump;
        $self->render(json => $data);
      });
    
    }
    
    1;
    

    For convenience and reliable testing a small client script:

    #!perl
    
    use strict;
    use warnings;
    
    use Mojo::UserAgent;
    
    my $ua = Mojo::UserAgent->new;
    
    my $tx = $ua->post('http://localhost:3000/checkaddress' => json =>
      {
        'id'  => "1",
      }
    );
    

    This script avoids JSON encoding problems.

    Even better would be, to write tests in the Mojolicious style.