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

Dancer deployment still confusing, difficult and a non-starter
by P Kishor 02 Aug '10

02 Aug '10

First, the perldancer.org domain was out for several days and emails to dancer-users mailing would bounce back ("rejected by recipient domain"). A conversation on IRC channel revealed that the DNS server was down, but nothing could be done about it until Sukrieh returned from a vacation. Would it be possible to not have such a single point of failure or blocking in the canonical, root domain of the web framework please? It gives the impression that the project has been abandoned. Nevertheless, while I am able to very quickly download, install and even create a basic dancer app, its deployment still remains a mystery to me. First, I will describe my working scenario in the hope that there might others with the same scenario, and then I will list what all I attempted and failed. I apologize for this email's length, but my hope is that it will lead to clearer and easier deployment notes with Dancer. I develop on my MacBook with Perl 5.12.1 installed under /usr/local/bin. My web projects live under ~/Sites, and are served by Apache2 running from /usr/local/apache2 (all custom installations). Any custom Perl libraries I develop go under ~/Library/Perl, and are available to all my web projects. I try to mimic the conditions on the actual production server as much as possible. One such server is a Mac OS X server, so its layout is almost identical to my MacBook, but another is a shared web host, most likely some variant of Linux. On that I get an html docs folder in my home folder, but I don't get access to tinkering with Apache which does all the serving. I can, for the most part, request custom Perl module installations, and I can use .htaccess files. Since these applications eventually get served from their own domain names, I try to not develop using http://localhost/app1 and http://localhost/app2. Doing so confuses me with regards to relative URLs and makes for a bit trickier development. Instead, I use virtual hosts with Apache, and I add the name of the virtual host to my /etc/hosts file. This allows me to get to my apps via http://app1.local and http://app2.local and so on. This way, when I eventually put the app in production, all I have to do is change the the host name from app1.local to app1.org and so on. While developing, I don't really worry about speed, so I just use cgi scripts with Apache... no persistent environment here. In fact, while on the Xserve I can install any persistent environment, on the shared web server I may not even have access to a persistent environment at all. So, I have to develop using the least common denominator, and then deploy with the best possible tools. Also, whatever deployment I choose, it is most likely to be Apache based. While it may not be the fastest, Apache is tried and tested, is available by default on whichever server I choose, and is even required by other projects. Now, on to deployment. The docs at Dancer::Deployment say that deploying http://localhost/dance/dispatch.cgi 500 Internal Server Error - Wrong http://localhost/dance/dispatch.cgi/ 200 OK - Right The above give me a generic Apache 404 error script not found or unable to stat: /Users/punkish/Sites/dance/dispatch.cgi File does not exist: /Users/punkish/Sites/dance/missing.html Actually, both of the above are wrong. It should really be http://localhost/myapp/public/dispatch.cgi/ But, then I get the following errors in Apache logs Unable to open /Users/punkish/Sites/dance/logs/development.log for writing, unable to log at /usr/local/lib/perl5/site_perl/5.12.1/Dancer/Logger/File.pm line 32, <DATA> line 16. Unable to open /Users/punkish/Sites/dance/logs/development.log for writing, unable to log at /usr/local/lib/perl5/site_perl/5.12.1/Dancer/Logger/File.pm line 32. Error while loading /Users/punkish/Sites/dance/app.psgi: unable to load application dance : Can't locate dance.pm in @INC (@INC contains: /Users/punkish/Sites/dance/public/lib /usr/local/lib/perl5/site_perl/5.12.1/darwin-2level /usr/local/lib/perl5/site_perl/5.12.1 /usr/local/lib/perl5/5.12.1/darwin-2level /usr/local/lib/perl5/5.12.1 /usr/local/lib/perl5/site_perl .) at (eval 60) line 2. BEGIN failed--compilation aborted at (eval 60) line 2. Premature end of script headers: dispatch.cgi File does not exist: /Users/punkish/Sites/dance/favicon.ico, referer: http://dance.local/public/dispatch.cgi/ File does not exist: /Users/punkish/Sites/dance/missing.html, referer: http://dance.local/public/dispatch.cgi/ I can fix the errors re. not being able to open development.log for writing by changing permissions on it chmod -R 777 logs but, the Dancer script that creates the logs folder should have set the permissions correctly automatically so Apache can write to it. Nevertheless, the other error is more serious... app.psgi is unable to load application dance because it can't locate dance.pm in @INC. If you see above, @INC contains 'dance/public/lib', but 'lib' is actually sitting one level above under 'dance'. So, I move 'lib' down to 'dance/public'. But, now I get a dancer 404, and the following errors in Apache logs File does not exist: /Users/punkish/Sites/dance/css, referer: http://dance.local/public/dispatch.cgi/ File does not exist: /Users/punkish/Sites/dance/missing.html, referer: http://dance.local/public/dispatch.cgi/ File does not exist: /Users/punkish/Sites/dance/favicon.ico, referer: http://dance.local/public/dispatch.cgi/ File does not exist: /Users/punkish/Sites/dance/missing.html, referer: http://dance.local/public/dispatch.cgi/ So, the interesting thing is, now I am getting the 404 via the dancer 404 template. So, dancer is running, and responding, but it is unable to grok the route. Plus, all the paths in the template are now wrong. Now what do I do? -- Puneet Kishor http://www.punkish.org Carbon Model http://carbonmodel.org Charter Member, Open Source Geospatial Foundation http://www.osgeo.org Science Commons Fellow, http://sciencecommons.org/about/whoweare/kishor Nelson Institute, UW-Madison http://www.nelson.wisc.edu ----------------------------------------------------------------------- Assertions are politics; backing up assertions with evidence is science =======================================================================

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If you like Dancer, say it :)
by Alexis Sukrieh 07 Jul '10

07 Jul '10

Hi, If you are a Dancer user and like the framework, there is a very good way to promote it. You can submit a CPAN rating review: http://cpanratings.perl.org/dist/Dancer Marketing is quite as important as code nowdays, and we should never forget about that. Promoting Dancer is helping the project, so give us a hand ;) Of course, if you run a blog or have a Twitter account, feel free to post and entry about Dancer. This will give more credit to Dancer and will be very appreciated! Thanks a lot. BTW I've just uploaded a new developer release[1] to CPAN, which provides new features, check the CHANGES[2] file. 1: http://search.cpan.org/~sukria/Dancer-1.1806_01/ 2: http://cpansearch.perl.org/src/SUKRIA/Dancer-1.1806_01/CHANGES Test reports are welcome as well! -- Alexis Sukrieh

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Problem with PLACK
by igor.bujna＠post.cz 07 Jul '10

07 Jul '10

Hello, I have problem, when starting my dancer aplication with plackup and in template use UTF8 characters such as "Čeština je pěkný jazyk". When I start aplication via Dancer start skript and after render the page, everything is ok. But when i start this via plackup and after render page i get message "body must be bytes and should not contain wide characters (UTF-8 strings)". This message is in file Plack/Middleware/Lint.pm in 'sub validate_res()' where test is: if (ref $res->[2] eq 'ARRAY' && grep utf8::is_utf8($_), @{$res->[2]}) { $croak->('body must be bytes and should not contain wide characters (UTF-8 strings).'); } When i comment this test the aplication, then run OK. I try this on http://github.com/sukria/ThisShit, when i put in main layout my UTF8 text "Čeština je pěkný jazyk". I think this problem is with plack, which can't use UTF8 text for rendering :(

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Re: [Dancer-users] Problem with PLACK
by Stephane 07 Jul '10

07 Jul '10

Hello, Did you try to do an "encode_utf8" before returning your content to Dancer (which then returns it to plackup)? I've had issues with encodings and Dancer, and the way I understand things, you must return bytes, not characters. The default stack does not enforce this, however. LWP works similarly as far as I can tell. The behavior you see is probably that your browser auto-detects UTF-8 when you use Dancer standalone (which doesn't verify the encoding and uses Perl's default handling of chars<->bytes conversion), while it seems that plackup verifies before sending. Stéphane

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Re: [Dancer-users] Private template in Dancer
by Alexis Sukrieh 30 Jun '10

30 Jun '10

[ add dancer-users(a)perldancer.org in CC ] Le 15/06/2010 09:14, igor.bujna(a)post.cz a écrit : > > Hello, Hello, First of all, please post this kind of question directly to the users mailing list, that way more people give attention to your problem and the better the support you get. > sory for my bad english first. > I try yours super framework and for me is missing than global vars for template. > I wanna defined something in before{} func and this will be in every template. > Forr me is simplest show how i use. > I call this as 'private_template' and its must be vars like that: > > set private_template => '1'; > before sub { > var private_template => { > test => "Hello world", > }; > }; > > I must make this patch for Dancer/Helper.pm > --- Dancer/Helpers.pm~ 2010-06-09 22:37:44.000000000 +0200 > +++ Dancer/Helpers.pm 2010-06-10 21:53:29.000000000 +0200 > @@ -54,6 +54,12 @@ > $tokens->{session} = Dancer::Session->get; > } > > + my $pt = exists($options->{'private_template'}) > + ? $options->{'private_template'} : setting('private_template'); > + if ($pt) { > + $tokens->{private} = > Dancer::SharedData->vars->{'private_template'}; > + } > + > my $content = Dancer::Template->engine->render($view, $tokens); > return $content if not defined $layout; > > ------------------------------------------------------------------------------------------------------------------------------------------- > Now in every template i can use this variables via 'private' call. > It must be enabled for every template via set private_template => '1' > Or can enabled or disabled separately in options 'private_template' in given > using template. > > It would be good to make something similar in this framework. > > Thank you and make dance Igor Bujna > Well, Franck Cuny has been rewriting a lot our template engiens recently and I'd like to have his point of view on this. My first opinion is that using settings for private template variables is not a good idea. Setting should remain.... setting ;) We also had in mind to provide a new kind of hook, called "before_template" which could process variables before any template is called. So I suppose we should wait for feedback from the team first. Regards, -- Alexis Sukrieh

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If you need some testing about dancer on WinOS
by sebastien deseille 30 Jun '10

30 Jun '10

Hello I work a lot on WinOS if you need some testing in this OS about dancer I'm available. -- regards Sebastien Deseille

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First Dancer drinkup meeting
by franck cuny 29 Jun '10

29 Jun '10

Hi all, As discussed with alexis, we want to organize a first drinkup meeting for Dancer's users and developpers in Paris the first of july. The idea is to meet in a pub, bring a laptop, and code/talk/share ideas. So if you're a user/contributor to dancer, or interested in web development with Perl (Plack!), please reply to the list so we can organize and decide a location :) -- Franck Cuny - http://lumberjaph.net GPG keyid: 0x1A6B0C28 - http://pgp.mit.edu/ "no rain but thunder, and the sound of giants ..."

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Uploaded files: what is their life-cycle?
by Daniel Pittman 16 Jun '10

16 Jun '10

G'day. I have been looking at the life of uploaded files in Dancer, since I need to perform a multi-stage interaction with my users while importing data from an Excel spreadsheet.[1] Anyway, as far as I can tell the default Dancer instance with 'load_app foo; start;' never deletes an uploaded temporary file. They just like on disk forever. So, I wondered: what is the life-cycle of them? Who should be deleting these files: - the underlying Plack (or internal) application server? - the HTTP::Body instance used by the Dancer core? - the Dancer core? - my application? My concern here is that none of them actually /do/ take responsibility for that, so right now anyone can fill the temporary space on my application server by sending requests to Dancer with files — ouch. FWIW, my personal preference would be that the Dancer core magically made this work, by ensuring that the files got deleted at the end of the request. Given that you can't robustly rely on storage within a single application server under Dancer[2], this makes the most sense — anyone who cares about that content will have arranged for it to persist during the request. Attached is the obvious, trivial, one-line patch that implements that, by telling the HTTP::Body instance to delete temporary files when destroyed. Daniel Footnotes: [1] Don't ask. It isn't really a choice. [2] ...because anyone could attach you to, say, a FastCGI Plack instance that forks multiple children, and you wouldn't even know until your application broke horribly. -- ✣ Daniel Pittman ✉ daniel(a)rimspace.net ☎ +61 401 155 707 ♽ made with 100 percent post-consumer electrons

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Dancer::Plugin::Database new features - dbi_params and on_connect_do settings
by David Precious 15 Jun '10

15 Jun '10

Just FYI, version 0.06 of Dancer::Plugin::Database has just been released, incorporating two new features, courtesy of Igor Bujna - thanks Igor! The changes are: * the ability to provide parameters to be passed to the DBI->connect call, e.g. RaiseError or AutoCommit * the ability to provide a list of queries which should be performed immediately upon connection to the database. An example configuration block, showing the new dbi_params and on_connect_do settings in use, is: plugins: Database: driver: 'mysql' database: 'test' host: 'localhost' username: 'myusername' password: 'mypassword' connectivity-check-threshold: 10 dbi_params: RaiseError: 1 AutoCommit: 1 on_connect_do: ["SET NAMES 'utf8'", "SET CHARACTER SET 'utf8'" ] Cheers Dave P -- David Precious <davidp(a)preshweb.co.uk> http://blog.preshweb.co.uk/ www.preshweb.co.uk/twitter www.preshweb.co.uk/linkedin www.preshweb.co.uk/facebook www.preshweb.co.uk/identica www.lyricsbadger.co.uk "Programming is like sex. One mistake and you have to support it for the rest of your life". (Michael Sinz)

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Re: [Dancer-users] (proposal) Re: Routes with captures
by Marc Chantreux 02 Jun '10

02 Jun '10

On Wed, Jun 02, 2010 at 12:28:50AM +0300, sawyer x wrote: > Good job Marc! :) I did it in less than an evening thanks to your (all Dancer programmers) awesome job writing a neat framework with a clean internal. thanks to you all! BTW: i finally vote for route_paren marc

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