[Dancer-users] Confused on error reporting

7 Jul 2011

      Hi all,

I've done some reading on how RESTful apps should respond to errors, but I'm
getting confused on how Dancer handles this for me.

My simple app:

package Test;
use Dancer ':syntax';
use Dancer::Plugin::Ajax;

# Case 1: Just a normal web page with layout
get '/error.html' => sub {
   eval {
        die "HTML die";
    } or do {
        send_error("HTML: You made a mistake", 400);
    };
};

# Case 2: A json call
get '/error.json' => sub {

   set serializer => 'JSON';

   eval {
        die "JSON die";
    } or do {
        send_error("JSON: You made a mistake", 400);
    };
};

# Case 3: HTML being return from an ajax call, thus no layout
ajax '/error.html'  => sub {

   eval {
        die "AJAX die";
    } or do {
        send_error("AJAX: You made a mistake", 400);
    };
};

With the environment set to development, each of these responds as I expect.
Case 1 gives me a full backtrace, case 2 gives me a a json with just the
error message, and case 3 again give me a full backtrace,

Now moving to the production environment. I get

$ curl http://127.0.0.1:3000/error.html

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
        "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html>
<head>
<title>Error 400</title>
<link rel="stylesheet" href="/css/style.css" />
<meta http-equiv="Content-type" content="text/html; charset=utf-8" />
</head>
<body>
<h1>Error 400</h1>
<div id="content">
<h2>Unable to process your query</h2>The page you requested is not available
</div>
<div id="footer">
Powered by <a href="http://perldancer.org/">Dancer</a> 1.3060
</div>
</body>

Which is OK, but where is the meaningful message to the user gone?

$ curl http://127.0.0.1:3000/error.json
"An internal error occured"

Again, not very useful.

$ curl  -H 'X-Requested-With: XMLHttpRequest'
http://127.0.0.1:3000/error.html

"An internal error occured"

I need to send something more than this back to the client.

What am I doing wrong?

If I declare my own error template:

set error_template => 'error';

Then, again, in development every thing is as expected, but in production I
get "An internal error occured" in all 3 cases.

My production,yml is the standard one.

Thanks for any insights.

Stephen

P.S.  occured should be occurred

[Dancer-users] Confused on error reporting

Stephen Fenwick-Paul