January 2021 - dancer-users - lists.preshweb.co.uk

Debugging sessions
by Nikola Mitev 29 Jun '23

29 Jun '23

Hi all, I have an annoyingly intermittent problem where on successful authentication the session info disappears and the user is endlessly redirected to the login page. It happens about once a month on a site with 10-20 logins daily. Once it happens to a user, it keeps happening for that user only. A restart of the app usually fixes the issue, and I am yet to see someone who had this problem to report it again at a later stage. Had about 10 cases so far in total. The cookie is generated on accessing the login page, stored in the browser and sent with the login POST request so I can verify cookies are enabled. The user is then authenticated, data added to the session including an 'authenticated' flag and they are redirected to their dashboard. Right before the redirection the session data is present. They make a request for the dashboard following the redirect, this triggers a session authenticated check which fails as no data is available for the session. They are then redirected for authentication and so on in a loop. If I restart the app the issue vanishes. hook before => sub { # <snip> if (!session('authenticated')) { forward '/login'; } } post '/login' => sub { # user authentication and session storage here, then the debug code and the redirecton: my $authenticated = session('authenticated'); $log->info("User authenticated ($authenticated), redirecting to $target_route"); return redirect $target_route; }; I don't have an explicit check on cookie size - not sure how to check it doesn't exceed 4K - but find it unlikely this is the issue. If that was the problem it should be happening persistently for a user regardless of restarts etc? Hope all this makes sense, I am looking for general advice on how to troubleshoot this but any ideas at all will be very much appreciated. Nik

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BUG? client disconnect not handled in delayed route
by Paul Clements 03 Feb '21

03 Feb '21

Hi, I've been having trouble getting the server (tried the default PSGI one and Starman) to notice when a client disconnects from a delayed route handler. Long story short, I was able to finally debug this down to the content subroutine in DSL.pm. With the change below, I'm now able to detect and properly handle a disconnect (in my case, I'm just hitting ^C on a client curl session). My question is: Does this seem like a proper fix (should I prepare a PR), or is there a better way to handle this? - Paul --- $ diff -pu git/Dancer2/lib/Dancer2/Core/DSL.pm . --- git/Dancer2/lib/Dancer2/Core/DSL.pm 2020-12-31 11:21:47.490454726 -0500 +++ ./DSL.pm 2021-01-23 11:07:47.464438846 -0500 @@ -328,7 +328,8 @@ sub content { } eval { - $Dancer2::Core::Route::WRITER->write(@_); + my $res = $Dancer2::Core::Route::WRITER->write(@_); + die "Write Error\n" if (!defined($res)); 1; } or do { my $error = $@ || 'Zombie Error';

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Dancer2 0.300005 Released
by Jason A. Crome 29 Jan '21

29 Jan '21

Well, it's been a hot minute since the last release, hasn't it? Dancer2 0.300005 has landed on CPAN and features a number of bug fixes, enhancements, and doc patches: 0.300005 2021-01-26 15:57:41-05:00 America/New_York [ BUG FIXES ] * GH #1546: Add MIME type for all files served from public (Russell @veryrusty Jenkins) * GH #1555: Remove all leftovers of warnings config setting (Sergiy Borodych) * GH #1557: Remove HTTP::XSCookies workaround (Alexander Pankoff) * GH #1564: Add script_name to redirects beginning with / (Nigel Gregoire) * GH #1567: Fix CSS so errors do not display ourside of <pre> HTML element (Elliot Holden) * GH #1568: Serializer::Mutable doesn't auto-load other serializers (Russell @veryrusty Jenkins) * GH #1579: Fix missing push_header method in Response::Delayed (Paul Clements) [ ENHANCEMENTS ] * GH #1552: Update jQuery (Sergiy Borodych) * GH #1558: Test to make sure uploads aren't discarded after the forward keyword is used (Alexander Pankoff) * GH #1571: Add GitHub Actions support (Gabor Szabo) * GH #1572: Install Dancer2::Session::Cookie in order to run the test t/issues/gh-811.t (racke) [ DOCUMENTATION ] * GH #1490: Document Dancer2::Core::App->template() (Steve Dondley) * GH #1551: Fix pod for cookie same site attribute (Sergiy Borodych) * GH #1562: Fix links, missing code in Tutorial (cloveistaken) I have already lined up a number of issues for inclusion into the next release, which should be landing in early February (as of now). Thanks for your patience with the long break between the releases, we (hopefully) won't do that to you again. Happy Dancing! See you in February! -- Jason A. Crome / CromeDome CPAN: https://metacpan.org/author/CROMEDOME GitHub: https://github.com/cromedome Twitter: https://twitter.com/cromedome Blog: https://cromedome.net

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Form modules?
by Morse, Richard E.,MGH 29 Jan '21

29 Jan '21

Hi! The various templating systems don't seem to be very useful for dealing with generating HTML forms that already have data in them, especially if some of the form needs to be generated programatically. What do people use for this instead? Thanks, Ricky The information in this e-mail is intended only for the person to whom it is addressed. If you believe this e-mail was sent to you in error and the e-mail contains patient information, please contact the Mass General Brigham Compliance HelpLine at http://www.massgeneralbrigham.org/complianceline . If the e-mail was sent to you in error but does not contain patient information, please contact the sender and properly dispose of the e-mail.

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Retrieving the current prefix?
by Morse, Richard E.,MGH 21 Jan '21

21 Jan '21

Hi! I'm starting to learn Dancer2. One question I have is whether it is possible to retrieve the current prefix in some way? In particular, I am showing a listing of things, and I would like to add an edit link. I have the following setup: prefix '/foo'; get '/' => sub { forward '/foo'; }; get '' => sub { my @rows = database->quick_select(...); foreach my $r (@rows) { $r->{'edituri'} = uri_for( '/foo/' . $r->{'id'}); } template 'foo.tt', { 'listing' => \@rows, 'adduri' => uri_for( '/foo/add' ) }; }; I feel like I should be able to get rid of the '/foo' bit in the `forward` and `uri_for` calls — if this changes, I now need to change it in multiple places, and could introduce a typo. I tried doing `uri_for( prefix . '/' . $r->{'id'})`, but that didn't work. If there isn't some obvious way to do this, how to other people manage these kinds of things? Thanks, Ricky The information in this e-mail is intended only for the person to whom it is addressed. If you believe this e-mail was sent to you in error and the e-mail contains patient information, please contact the Mass General Brigham Compliance HelpLine at http://www.massgeneralbrigham.org/complianceline . If the e-mail was sent to you in error but does not contain patient information, please contact the sender and properly dispose of the e-mail.

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CI using GitHub Actions
by Gabor Szabo 12 Jan '21

12 Jan '21

Hi, I have already started to work on this, but I would be glad to get your input on setting up CI on GitHub Actions: https://github.com/PerlDancer/Dancer2/issues/1571 Gabor

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Best way to log from wherever?
by Aaron Hall 08 Jan '21

08 Jan '21

Hi all, Happy New Year. :) What is the current thinking on the "best" or "right" way to log from all parts of your program? I wrestle with this occasionally. I'm not a programmer by trade (these are mainly personal/hobby projects, although I have done stuff for $WORK before), so it seems to me that maybe there's some best practice that I just haven't picked up on. I want to be able to log from any part of my program, have all the logs go through the same processing, and come out in the same place, with a minimum of fuss. Preferably using the same simple debug/info/warning/error APIs (from the logging client's point of view). For the web-facing portions of the app, that's simple enough: "use Dancer2 appname => ..." and be happy. By "any part of my program", I'm thinking of code that doesn't use Dancer2 and so doesn't get the DSL. * Methods in DBIx::Class::Result classes. (Mainly for debugging.) * app.psgi, where I might add a middleware that wants to log something. * Utility modules that don't handle routes and don't use Dancer2. (Maybe they should anyway?) These days, I usually make a "MyApp::Log" module and do something like: package MyApp::Log; use Dancer2 appname => 'MyApp::App'; use Exporter qw/import/; our @EXPORT = qw/debug info warning error/; That actually works pretty nicely; should I just do that? It feels like if that's supposed to be the way, it wouldn't require playing tricks with import(). Once I went so far as to write a Dancer2::Logger::App (never uploaded anywhere) that would call my app back to log, and consolidating the output stream that way. That was kinda fun, but after I did it I felt like I'd re-invented the wheel inside-out. I know there's a giant ecosystem of logging modules on CPAN. I've even played with Log::Any. I suspect the solution involves using one of them, but talking about the data flows gets so abstract I have trouble getting my head around how to use them to make the various sources send logs to the same place, where to configure it all from, and so on. Can someone help straighten me out on this? :) - Aaron -- Aaron Hall Sleep, where is thy sting? vitaphone.net Bed, where is thy victory?

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Dancer2: Create a configuration for testing
by Mikko Johannes Koivunalho 07 Jan '21

07 Jan '21

Hi. I have a Dancer2 app. I want to test it properly against a database. For every test run I create a new database and a new empty schema (PostgreSQL). My new database has a random name (e.g. app_123abc) and at the end of the test I drop the database. How can I change the Dancer2 app configuration during the test run, or before I do my $test = Plack::Test->create( $app ); ? As it is, is just loads the config files for development. I want to provide my own configuration programmatically. Creating files in the current directory is not an option. I have tried: config->{'my_stuff'} = \%my_stuff set 'my_stuff' => \%my_stuff but Dancer2 doesn't seems to pick it up or it gets overwritten later by the config from the files. Example: #!/perl ## no critic (Modules::ProhibitMultiplePackages) use strict; use warnings; use 5.014; # JSON::PP included in CORE. package ConfigChangeTest; use Dancer2; set serializer => 'JSON'; get qr{/info}msx => sub { return { appname => config->{'appname'}, }; }; package main; use Test2::V0 -srand => time, qw(:DEFAULT); use Plack::Test; use HTTP::Request; use JSON; use Dancer2; my $appname = 'ConfigChangeTest'; set appname => $appname; my $test = Plack::Test->create( ConfigChangeTest->to_app ); my $req = HTTP::Request->new( GET => '/api/1/info' ); my $res = $test->request( $req ); ok( $res->is_success, 'Is success' ); # Fails! # appname is the one set in the file `environments/development.yml` or + file `config.yml`. is( decode_json $res->content, { appname => $appname, }, 'Is right con +tent' ); done_testing; -- Mikko Koivunalho LinkedIn: http://www.linkedin.com/in/MikkoKoivunalho AboutMe: http://about.me/mikkokoivunalho Blog: http://www.koivunalho.org/blogs/exercises-in-integration-and-delivery/ [ This message has been signed with PGP. Public key attached. ]

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