September 2011 - dancer-users - lists.preshweb.co.uk

deploying many, many apps
by Puneet Kishor 14 Sep '11

14 Sep '11

I have asked, or hinted at, other variants of the same question, but here again -- I am now developing and deploying many Dancer apps. Have been experimenting with, and am quite happy with Starman serving them hiding behind Apache2 proxies. My home grown, amateurish web_ctl [https://github.com/punkish/web_ctl] helps me manage them as well. However, with every app, I am starting an additional 10 Starman processes, so now already I have about 60 Starman processes running on my computer. 1. Why 10? I once tried 2 Starman processes for a very, very low traffic app, and found it coughing and sputtering, but surely, 10 is too many, isn't it? 2. Why not Apache2 with mod_perl or fastcgi or mod_psgi? Apache seems to launch 5-10 "children," but no matter how many apps are being served by it, that number of child processes seems to hover around that number. It doesn't get to n * 10 for Starman? The Starman approach does have one clear advantage -- each app can be turned off or on separately without having to restart Apache entirely. I want to get the crowd-wisdom on serving, say 50 different Dancer apps on the same computer. The apps will range from very, very low traffic to moderate traffic. However, all the apps will be data-intensive, in that, even if the number of user-hits on the server are few per hour, each hit does a fair bit of database work and sends back largish amounts of data. Data may be on the same or a different server -- that part is out of the scope for this thread. Many thanks in advance. Puneet.

4 5

Dancer::Plugin::EncodeID
by Assaf Gordon 13 Sep '11

13 Sep '11

Hello dancers, My first attempt at a plugin: a simple utility to encode/obfuscate internal IDs in URLs. With this plugin, your users will see URLs such as: http://myserver.com/item/c98ea08a8e8ad715 instead of http://myserver.com/item/42 You can find it here: https://github.com/agordon/Dancer-Plugin-EncodeID Comments are very welcomed, -gordon

2 1

Dancer::Plugin::Email problem with checking email failures
by Assaf Gordon 12 Sep '11

12 Sep '11

Hello, I'm having problems checking the return status of email sending with "Dancer::Plugin::Email" . The first example in the "code recipes" of "Dancer::Plugin::Email" shows the following: ---- post '/contact' => sub { my $msg = email { to => '...', subject => '...', message => $msg, encoding => 'base64', attach => [ '/path/to/file' ] }; warn $msg->{string} if $msg->{type} eq 'failure'; }; ---- This is the actual code I used: --- get '/emailtest' => sub { my $msg = email { to => 'gordon\(a)cshl.edu', subject => 'Dancer::PlugIn::Email Test', message => "Hello World from Dancer::Plugin::Email", }; warn $msg->{string} if $msg->{type} eq 'failure'; return "Email Sent!\n"; }; --- This is the error I get: ------------ Warning caught during route execution: Use of uninitialized value in string eq at /home/gordon/projects/perl_dancer_test/user_email_verification/lib/user_email_verification.pm line 80. /home/gordon/projects/perl_dancer_test/user_email_verification/lib/user_email_verification.pm around line 80 77 subject => 'Dancer::PlugIn::Email Test', 78 message => "Hello World from Dancer::Plugin::Email", 79 }; 80 warn $msg->{string} if $msg->{type} eq 'failure'; 81 return "Email Sent!\n"; 82 }; 83 ----------- Trying to dig a little deeper, it seems "$msg" is a "Return::Value" object, and that class is deprecated. Also, "$msg->{type}" returns an empty string (so it's not the problem), but "$msg->{string}" returns undef. and "Data::Dumper($msg)" gives: ----- $VAR1 = bless( { 'prop' => {}, 'string' => 'success', 'type' => 'success', 'errno' => undef }, 'Return::Value' ); ---- I'm using Perl 5.10.1 , Dancer 1.3702, Dancer::Plugin::Email 0.1300 . Any suggestions how to solve this ? Thanks! -gordon

2 1

Dancer::Plugin::ValidateTiny
by Alexey Kolganov 09 Sep '11

09 Sep '11

Hello hackers! I just wrote a new plugin for validating forms, that using Validate::Tiny module. It's very simple and pretty for validating small forms on your site. You can find it here: https://github.com/kalgan/Dancer-Plugin-ValidateTiny Also, there you can find an example app for using this plugin. Any feedbacks and bug reports are welcome! -- Best regards, Alexey.

2 1

"sensitive" config data in SCM
by Mr. Puneet Kishor 08 Sep '11

08 Sep '11

Not a Dancer question per se, but I am sure a few of you have encountered this, and it is a "best practice" issue I am encountering for my Dancer apps, so -- I have hard at work learning Git, striving to put all my work in a Git repo (including Github, where appropriate). Yesterday I realized that I would be committing my database and other passwords to the repo as well (I am using the most excellent Dancer::Plugin::Database). A little bit of searching brought me to the conclusion that I had to implement some kind of "smudge" and "clean" filters using .gitattributes -- so when I commit my work to the repo, the sensitive info would get replaced by **** (or other placeholders), and when I would checkout the work, the placeholders would get replaced by the real info. Before I waste too much time learning and implementing these smudge and clean filters, it would behoove me to ask if one of you already has those in place, and if you would kindly share them with me and the community... appropriately via Github. Many thanks in advance, Puneet.

3 5

Problem in normalize_path
by Oleg A. Mamontov 07 Sep '11

07 Sep '11

Hello. There is a new bug in &Dancer::FileUtils::normalize_path at 1.3072 :( Sample test: use Dancer::FileUtils 'path'; use Test::More 'no_plan'; is path('a/../b') => 'b'; is path('a/b/../../c') => 'c'; is path('a/b/c/../../../d') => 'd'; Output: ok 1 ok 2 not ok 3 # Failed test at t/q line 8. # got: 'a/b/d' # expected: 'd' There is wrong usage of regex with /g modifier. Simple patch is below: --- Dancer/FileUtils.pm.orig 2011-09-06 01:11:42.000000000 +0400 +++ Dancer/FileUtils.pm 2011-09-06 01:11:49.000000000 +0400 @@ -102,8 +102,7 @@ }x; $path =~ s{/\./}{/}g; - $path =~ s{$seqregex}{}g; - $path =~ s{$seqregex}{}g; + while ( $path =~ s{$seqregex}{} ) {} return $path; } But, imho, it's a bad idea to do any kind of 'universal path normalization'. What's the point? Only desire for aesthetics? Underlying FS is able to do it more reliable any case. POD on &File::Spec::canonpath talks us: "Note that this does *not* collapse x/../y sections into y. This is by design. If /foo on your system is a symlink to /bar/baz, then /foo/../quux is actually /bar/quux, not /quux as a naive ../−removal would give you. If you want to do this kind of processing, you probably want "Cwd"’s "realpath()" function to actually traverse the filesystem cleaning up paths like this." How do you suppose to handle hierarchy with symlinks? And &Cwd::realpath works like (3) realpath: "All components of file_name must exist when realpath() is called." Perhaps the best way is to drop path normalization code from Dancer::FileUtils completely? -- Cheers, Oleg A. Mamontov mailto: oleg(a)mamontov.net jabber: lonerr(a)charla.mamontov.net icq uin: 79-521-617 cell: +7-903-798-1352

2 1

Deploying two dancer apps in same virtual host on apache
by Alex Tang 06 Sep '11

06 Sep '11

Hi folks. I have two dancer apps (a front end UI, and a backend REST server) that i want to have deployed as separate dancer apps. I'd like to do this using apache. i can do it in any way under apache (i have the freedom to configure things most anyway i need). I've successfully deployed two apps using two different virtual hosts, however in this case, the frontend app sends pages back to the browser that contain AJAX requests that want to talk directly to the backend app. I can't do this via two different virtual hosts due to same-origin-policy, so i need to deploy both apps under the same virtual host. Any ideas on how to do this? I've been messing with the config files for a couple of hours, but to no avail. I checked on "the google", and on the dancer website, but the deployment guide only talks about multiple sites on the same host using Plack::Builder and starman, and to be honest, i don't really understand PSGI and Plack. Thanks a bunch. ...alex... PS, the latest version of my apache virtual host config can be found at http://paste.perldancer.org/2298W43paS2hg. It kind of works, but i think it only works because depending on how the apache worker was initialized, it's using one or the other dancer app.

3 3

web_ctl
by Mr. Puneet Kishor 03 Sep '11

03 Sep '11

I have created web_ctl.pl (with associated web_ctl.conf), a simple command line interface to managing Starman-powered Dancer apps. The git repo is at https://github.com/punkish/web_ctl It is nothing fancy, certainly not for you wizards out there, but I am finding it very useful to start/stop and to keep track of my various Dancer apps. Please feel free to suggest improvements. -- Puneet Kishor

1 0

giving the Dancer process via Starman a name
by Mr. Puneet Kishor 02 Sep '11

02 Sep '11

when I run `plackup -s Starman -p 5006 -w 10 -E development --access-log /path/to/app_access.log --error-log /path/to/app_error.log -D --pid /path/to/app.pid -a /path/to/app/bin/app.pl` it shows up in `ps` as 'starman master' and 'starman worker' punkish@Lucknow ~/bin$ps -fax | grep '[s]tarman' 501 4882 1 0 7:54AM ?? 0:00.04 starman master 501 4883 4882 0 7:54AM ?? 0:00.00 starman worker 501 4884 4882 0 7:54AM ?? 0:00.00 starman worker 501 4885 4882 0 7:54AM ?? 0:00.00 starman worker 501 4886 4882 0 7:54AM ?? 0:00.00 starman worker 501 4887 4882 0 7:54AM ?? 0:00.00 starman worker Is there anyway I can make those processes have specific names, for example, 'app master' and 'app worker" in the above instance?

4 3

Perl developer roles with Dancer experience in London / telecommuting
by David Precious 02 Sep '11

02 Sep '11

Just a quick message to say that my employer are looking for talented Perl developers, preferably with some experience with Dancer (although that's not essential), to work either in London or working from home / telecommuting most of the time. with a day a week in the London-based office. Good company, good salary & benefits, a talented team already in place, and free beer :) We're mainly looking for permanent roles, but contract roles may be considered too. If anyone is interested, feel free to contact me for more details! -- David Precious ("bigpresh") http://www.preshweb.co.uk/ "Programming is like sex. One mistake and you have to support it for the rest of your life". (Michael Sinz)

1 0