April 2017 - dancer-users - lists.preshweb.co.uk

How can a fork+system() Dancer app not create zombie processes?
by Shlomi Fish 29 Jun '17

29 Jun '17

Hi all! When running a simple and reduced Dancer 1 application which forks and runs perldoc -f system , I am getting many zombie processes after making requests. This does not happen with https://github.com/shlomif/shlomif-perl-snippets/blob/master/tcp-socket-ser… which does the same thing using IO::Socket and plain TCP. To reproduce, do: hg clone https://shlomif@bitbucket.org/shlomif/app-notifier cd app-notifier hg checkout zombies-processes-bug cd App-Notifier-Service/ And then run “bash run-server.bash” and in a different shell session “bash run-client.bash.” . You can run 'pstree -p' to see the zombies processes. This happens on Mageia v6 x86-64 and Fedora 25 x86-64 with perl-Dancer-1.320.200-2.mga6 . I am quoting a discussion I had on #dancer on irc.perl.org about it. Any further insights about a solution will be welcome. Regards, Shlomi Fish ``` Apr 02 16:47:21 <rindolf> Hi all! My dancer service here (run run-server.bash and then run-client.bash in the App-Notifier-Service directory and note the branch) generates many zombie processes - how can I prevent it from happening? https://bitbucket.org/shlomif/app-notifier/branch/zombies-processes-bug Apr 02 16:54:58 <racke> how do you start the dancer service? Apr 02 16:55:57 <rindolf> racke: perl -I"`pwd`/lib" bin/app.pl --port=6300 Apr 02 16:56:25 <racke> so that is Dancer 1 ? Apr 02 16:56:40 <rindolf> racke: yes, it is Apr 02 16:58:36 <racke> you start only one instance so i might not be able to handle the incoming request Apr 02 16:59:32 <rindolf> racke: it handles most requests fine Apr 02 16:59:36 <racke> better use something like plackup -s Starman --workers=5 Apr 02 17:01:13 <rindolf> racke: what do I need it for? Apr 02 17:01:38 <racke> as I explained before Apr 02 17:01:44 <racke> you need more than one instance Apr 02 17:02:33 <rindolf> racke: see https://metacpan.org/pod/App::Notifier::Service for my use case Apr 02 17:02:38 <rindolf> racke: why? Apr 02 17:03:08 <rindolf> racke: i don't need to handle moer than one request at the time Apr 02 17:03:23 <racke> hm Apr 02 17:03:30 <racke> if you think so Apr 02 17:05:01 <racke> you probably don't handle fork correctly, that is likely to cause your zombies Apr 02 17:05:27 <rindolf> racke: I followed perldoc perlipc Apr 02 17:10:42 <racke> well why not use something like IPC::RUn? Apr 02 17:16:33 <rindolf> racke: 1. I used fork+system - it is enough for my needs, 2. I provided a link to the code - did you take a look? 3. I found IPC::Run buggy when i used it in a different project Apr 02 17:17:22 <rindolf> racke: and also - this is the reduced-to-a-minimum code Apr 02 17:19:23 <racke> yeah I did take a look Apr 02 17:19:49 <rindolf> racke: ok, thanks! Apr 02 17:20:09 <racke> I am not familar with using fork so ... Apr 02 17:20:33 <racke> but it looks like it produces your army of zombies :-) Apr 02 18:01:22 <rindolf> racke: the IO-Socket-INET equivalent does not spawn any zombies - https://github.com/shlomif/shlomif-perl-snippets/blob/master/tcp-socket-ser… Apr 02 18:07:07 <rindolf> http://stackoverflow.com/questions/13614498/forking-to-run-code-in-a-child-… - there is this too ``` -- ----------------------------------------------------------------- Shlomi Fish http://www.shlomifish.org/ My Favourite FOSS - http://www.shlomifish.org/open-source/favourite/ Chuck Norris can end world hunger, but he thinks that hungry people make humanity a more challenging adversary. — http://www.shlomifish.org/humour/bits/facts/Chuck-Norris/ Please reply to list if it's a mailing list post

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Second cookie [ for 'remember me' username only ]
by Nathan Bailey 24 Apr '17

24 Apr '17

Hi all, I'd like to have a 'remember me' cookie for users who want their username to be remembered by the browser (but not the password). Dancer2::Core::Role::SessionFactory's set_cookie_header seems quite specific to sessions, so it appears that the right/best way to do it is to use push_header (as set_cookie_header does), viz: if (is_successful_login && defined params->{remember_me} && params->{remember_me}) { push_header( 'Set-Cookie', (remember_me_user => session('user')) ); } Is there a well-defined pattern for this? cheers, Nathan

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Starman large file upload
by Zahir Lalani 18 Apr '17

18 Apr '17

Hi All Hit a bit of a wall We are using a standard jquery uploader connected to Dancer2 and that in general works great We are testing uploading large files (600M) and having a lot of issues: We see the file uploading to /tmp as expected. At the end of the upload, Starman has a lot of CPU and Mem usage and the defined upload route (our code) does not get hit for several minutes. It looks like Starman is loading this into memory and hitting swap issues Apart from increasing memory - is there something specific we should be doing to resolve this? Zahir Lalani Head of Development & Architecture [cid:96F784CA-E917-4CC1-A9A9-96CBDA2AF2BC] 151 Rosebery Avenue, London, EC1R 4AB m: +44 (0)7956 455168 t: +44 (0)203 142 3619 e: zahirlalani@oliver<mailto:zahirlalani@oliver-marketing.com>.agency w: www.oliver.agency

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Dancer2: What is the right way to design a reusable web component?
by vijayvithal jahagirdar 07 Apr '17

07 Apr '17

I would like to use some components across multiple websites and am looking for the best way to package them for reuse. For e.g. say a login page or an admin page will have some static component, some views and some routes +logic. My first thought was to package them into a plugin, but then how do I instruct my main app to pick up the component related views and static files from the plugin folder instead of the views and public folder of my app folder? What is the right way to do this? -- https://www.facebook.com/vijayvithal.jahagirdar https://twitter.com/jahagirdar_vs http://democracies-janitor.blogspot.in/

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Fwd: DPAE and reset passwords (Dancer2::Plugin::Auth::Extensible)
by Nathan Bailey 05 Apr '17

05 Apr '17

On 3 April 2017 at 19:38, Andrew Beverley <andy(a)andybev.com> wrote: > On Mon, 3 Apr 2017 19:15:31 +1000 Nathan Bailey wrote: > > but then clicking the 'Reset password' button doesn't seem to do > > anything. > > As in does a POST request and forwards back to the same page, or > nothing at all? > Back to the same page. > > The "$app->log(...)" statements don't seem to be appearing anywhere, > > is there a 'debug' mode I need to turn on or a config setting to > > direct the logging to a file/Log::Report? > > Yes, you can configure that per-dispatcher (with the mode changed to > DEBUG) but probably easier just to do: > > use Dancer2::Plugin::LogReport mode => 'DEBUG'; > That's in my Main and Extensible.pm but still doesn't seem to give me joy (other logging is working fine, but nothing from Extensible.pm) I've put my own 'warn' statements in each subroutine to see the flow (see below). DPAEPD lacked a 'get_user_by_code' function; I've added the following and now the reset password process is happy. sub get_user_by_code { my ($self, $code) = @_; croak "code must be defined" unless defined $code; # Get our database handle and find out the table and column names: my $database = $self->database; # Get just the username of the user with the matching pw_reset_code my $user = $database->quick_lookup( $self->users_table, { 'pw_reset_code' => $code }, 'username' ); if (!$user) { $self->plugin->app->log("debug", "No such code $code"); return; } else { return $user; } } However, when I try to log in with my reset password, I'm stuck in a loop at https://metacpan.org/source/HORNBURG/Dancer2- Plugin-Auth-Extensible-0.703/lib/Dancer2/Plugin/Auth/Extensible.pm#L266; my home page doesn't seem to want to load. I have a 'get' route for '/' but perhaps something is missing somewhere logged_in_user at /Library/Perl/5.18/Dancer2/Plugin/Auth/Extensible.pm line 593. get_user_details at /Library/Perl/5.18/Dancer2/Plugin/Auth/Extensible.pm line 571. plugin-get_user_details at /Library/Perl/5.18/Dancer2/ Plugin/Auth/Extensible/Provider/Database.pm line 375. Use of uninitialized value in concatenation (.) or string at /Library/Perl/5.18/Dancer2/Plugin/Auth/Extensible.pm line 265. Get here, return_url='', home page='/' at /Library/Perl/5.18/Dancer2/Plugin/Auth/Extensible.pm line 265. thanks, Nathan

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DPAE and reset passwords (Dancer2::Plugin::Auth::Extensible)
by Nathan Bailey 03 Apr '17

03 Apr '17

I'm trying to set up resetting passwords with DPAE (Dancer2::Plugin::Auth::Extensible). When I get a "please follow the link below" email, and click on the link, I'm directed to the standard login page, with "You need to log in to continue" (username/password or password reset). I would expect to be directed to a page asking me for the token, or asking me for a new password, or ...? thanks, Nathan PS: My config is below: Auth::Extensible: # After /logout: If no return_url is given: land here (no default) exit_page: '/' # Mailer options for reset password and welcome emails mailer: module: Mail::Message # Email module to use options: # Options for module via: sendmail # Options passed to $msg->send mail_from: 'example <me(a)example.com>' # From email address # Set to true to enable password reset code in the default handlers reset_password_handler: 1 #password_generator: eAlpaca::User::random_pw # Optional random password generator # Set to a true value to enable recording of successful last login times record_lastlogin: 1 realms: users: provider: 'Database' users_table: 'my_user_table' roles_table: 'user_roles' user_roles_table: 'my_user_roles_table' # roles_id_column: 'id' # roles_role_column: 'role' user_roles_user_id_column: 'my_id' # user_roles_role_id_column: 'roles_id'

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Less granularity from Log::Report than default logging (Was: RESOLUTION: Dancer2::Plugin::LogReport - basic setup)
by Nathan Bailey 03 Apr '17

03 Apr '17

The original issue (in email below) is definitely fixed (I get a nice Log::Report error from it). In a similar vein, however, there is a difference in feedback to the browser with Dancer2::Plugin::Auth::Extensible (trying to get my customised login page working). 1. With Log::Report turned on: Internal Server Error Can't call method "uri" on an undefined value at /Library/Perl/5.18/Dancer2/Plugin/LogReport.pm line 228. 2. Without Log::Report turned on: *Error 500 - Internal Server Error* *Runtime Error* Undefined subroutine &Dancer2::Plugin::Auth::Extensible::login called at /Library/Perl/5.18/Dancer2/Plugin/Auth/Extensible.pm line 282. /Library/Perl/5.18/Dancer2/Plugin/Auth/Extensible.pm around line 282 277 { 278 $app->request->parameters->set('password_code_valid' => 1), 279 } 280 281 no strict 'refs'; 282 return &{ $weak_plugin->login_page_handler }($weak_plugin); 283 }, 284 ); 285 286 $app->add_route( 287 method => 'get', Note that the log file does contain the full report (ie. this is a workable problem, in that I can just go to the log file for the full detail of the issue). cheers, Nathan On 10 February 2017 at 04:08, Andrew Beverley <andy(a)andybev.com> wrote: > On Tue, 7 Feb 2017 Andrew Beverley <andy(a)andybev.com> wrote: > > On Thu, 5 Jan 2017 Nathan Bailey <web(a)polynate.net> wrote: > > > Hi all (especially Andy :-) > > > > Sorry for the delay on this Nathan. > > > > > What are you supposed to put in your non-main route handlers? > > > use Dancer2::Plugin::LogReport mode => 'DEBUG'; (like main route > > > handler); OR > > > use Log::Report; (like other modules) > > > > I can now say that it /should/ be the same as any other route > > handlers. So wherever you have: > > > > use Dancer2; > > > > You should also have: > > > > use Dancer2::Plugin::LogReport ... > > > > Although if you're using the same appname (appname => ...) then you > > only need to use Log::Report. > > > > The reason being that otherwise the required logging hook isn't > > inserted into that particular app. > > > > However, there is a problem with the way the current version of the > > plugin works, which means that the correct DSL isn't always available > > to it. This will cause some unexpected behaviour. I'm working on a fix > > at the moment. > > Fix included in aforementioned v1.19 Log::Report release. Let me know > if you run into any other problems. > > Regards, > > Andy > _______________________________________________ > dancer-users mailing list > dancer-users(a)dancer.pm > http://lists.preshweb.co.uk/mailman/listinfo/dancer-users >

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