December 2015 - dancer-users - lists.preshweb.co.uk

D2 compatibility with Perl 5.8
by Warren Young 14 Jan '16

14 Jan '16

We recently rejected a plan to migrate to D2 when we discovered that Dancer2::Text::Xslate requires Perl 5.10. We still have to support 5.8 because we have an existing fleet of CentOS 5 boxes which aren’t going away any time soon. (Upgrading them in the field is as good as impossible, and we lack a good business reason to have them shipped back to be upgraded. They won’t go away until our customers just stop using them, or they fall over dead and need to be replaced.) Is dropping Perl 5.8 support an intentional move? If so, we’ll have to stick with D1 for years to come. I know the Modern Perl movement is trying to get beyond 5.8, but the fact is, it was the primary version of Perl for nearly 5 years, so it left a big “pulse” in the timeline that will take a long time to dissipate. Incidentally, a big factor in our choice to use Dancer 1 was that it still supports Perl 5.8. We rejected Catalyst and Mojolicious without even evaluating them because they both require Perl 5.10.

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Non-blocking stuff
by David H 12 Jan '16

12 Jan '16

Hi All, I'm looking for some advice/pointers on having stuff non-block in my code. I have an application which runs on Dancer2 and is ~12,000 lines of code. It is actually (currently) four separate applications. It works really really well at the moment but for one thing, and that is that it continually blocks on pretty much everything. I've tried various solutions including starman which doesn't seem to run its allocated 10 workers for some reason. I've seen the model of nodejs and I'm looking for something similar to the call-back event non-blocking model of nodejs. I've tried using the apache road but that seems to recompile on every request, which adds ~ 1.5 seconds to each request, since that is the application startup time. Keen to see how other people solve this. Thanks, David

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Medium-Scale Dancer series updated
by Warren Young 29 Dec '15

29 Dec '15

I’ve just finished a touch-up pass on my series of articles on getting beyond the initial small-scale app design generated by “dancer -a app”. They were to be part of the 2015 advent calendar, but for now, here are the current links: Part 1, modules: https://goo.gl/SFn30N Part 2, routes: https://goo.gl/UfMqGo Part 3, views: https://goo.gl/DN8xYO Part 4, front end: https://goo.gl/wlyOFB Part 5, REST API: https://goo.gl/VbMI4P Part 6, reloader: https://goo.gl/6AiiIm (These are GitHub links, showing the current tip-of-master versions, shortened so they don’t break due to line wrapping.) The major change is that I’ve replaced the context object idea with direct Dancer DSL calls. I had poor justifications for this object, which I realized after watching Alexis Sukrieh’s 2015 conference video. That in turn allowed me to drop a level of function calls, which makes the recommended design considerably cleaner. I’ve also fixed up some UTF-8 problems, so you don’t get broken Latin-1 characters when viewing the articles in a web browser. (They look fine on a UTF-8 terminal. :) )

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Calling all plugin authors and plugin users
by Sawyer X 29 Dec '15

29 Dec '15

Hi everyone and merry $whatever_you_celebrate! Yesterday I finished the last patches to our new plugin system branch[1], supporting the old plugin syntax while working with the new one. There are two exceptions, mentioned in the original PR[2]: * You cannot call `use Dancer2` in the plugin. We currently do not detect this. We might be able to add this check. * You cannot import specific keywords from a plugin. We might be able to support it in the future, but it isn't supported at the moment. We do detect this and croak() if we see it happen, so you know what to do. Other than that, the old syntax seems to work. I want to ask all plugin authors to test their plugins. All users are also asked to report any issues. We would like to release a tentative trial version this weekend and, if all goes well, push this to production soon after. The plan is to then deprecate the old plugin syntax. We haven't decided yet what the timeline should be (a month, six months, two releases, six releases, etc.) but we will openly discuss this and are interested in all suggestions and comments. I have opened a ticket[3] to track all plugins we work with and the changes they might require (if they fall on one of the first two cases indicated above). We would appreciate any and all help! I will try and write a utility that automatically checks plugin code for the aforementioned problems. Please let us know if and how we can help you help us help you help all of us. :) Sawyer. [1] https://github.com/PerlDancer/Dancer2/tree/plugins-yanick [2] https://github.com/PerlDancer/Dancer2/pull/1010 [3] https://github.com/PerlDancer/Dancer2/issues/1078

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Videos 2015 + Conference 2016
by Stefan Hornburg (Racke) 17 Dec '15

17 Dec '15

The Perl Dancer Conference proudly presents the videos from the talks in Vienna: https://www.youtube.com/playlist?list=PLf1KDvMbyeCQq4mkMt8jDPzS9uPUX_mNo Thanks to our sponsors (https://www.perl.dance/sponsors) without their support this extensive coverage wouldn't be possible. Thanks to Amanda Crow at A. Crow Editing for the intricate editing work. The feedback from the speakers and other participants was really encouraging, so we are going to start planning for next year's event in January. Please feel free to make suggestions about venue, schedule and everything else which could be improved for 2016. Regards Racke -- Perl and Dancer Development Visit our Perl::Dancer conference 2015. More information on https://www.perl.dance.

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Dancer2 deployment
by Richard Reina 09 Dec '15

09 Dec '15

Happy Saturday All, For the past few months I've been playing around with dancer on a machine at home. I am wanting to now experiment with creating and perhaps deploying a simple web app on digitalocean. However, I am not clear why I need a web server such as Starman. Can I not just install Dancer2 and plackup like I do on my local machine? Thanks

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Dancer2::Plugin::Auth::Extensible problem - likely me
by John Stoffel 05 Dec '15

05 Dec '15

I'm trying to play with Authentication in Dancer2, and I can't get the dang example from Gabor at his blog (http://perlmaven.com/password-protecting-web-pages-in-dancer2) to run, it keeps giving me the following error: No Auth::Extensible realms configured with which to authenticate user at /home/stoffj/perl5/perlbrew/perls/perl-5.14.2/lib/site_perl/5.14.2/Dancer2/Plugin/Auth/Extensible.pm line 1160. HTTP::Server::PSGI: Accepting connections at http://0:5000/ And I'm going a little crazy. I'm using a perlbrew interpretter on CentOS 6.7, runnning perl 5.14.2, with all the latest modules installed. >From looking at the Extensible.pm file, it's warning from the on_plugin_import() sub where it's looking for Realms. I've got the following config.yml file setup: show_errors: 1 session: "YAML" logger: console log: core plugins: Auth::Extensible: realms: config: provider: Config users: - user: 'foo' pass: 'bar' name: 'George Foo' roles: - Marketing - user: 'bar' pass: 'foo' name: 'George Bar' roles: - Testing - Marketing - Management And my app.pl looks like this: #!perl # use strict; use Dancer2; use Dancer2::Plugin::Auth::Extensible; get '/' => sub { return 'This is a public page. Everyone can see it. Check out the <a href="/report">report</a>'; }; get '/report' => require_role Marketing => sub { return 'Only authenticated users should be able to see this page'; }; dance; And I'm invoking it like this: ~/tmp/Dancer2> ../../perl5/perlbrew/perls/perl-5.14.2/bin/plackup -R . app.pl Watching . ./lib app.pl for file updates. No Auth::Extensible realms configured with which to authenticate user at /home/stoffj/perl5/perlbrew/perls/perl-5.14.2/lib/site_perl/5.14.2/Dancer2/Plugin/Auth/Extensible.pm line 1160. HTTP::Server::PSGI: Accepting connections at http://0:5000/ So does anyone see what I'm going wrong here? Thanks, John

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