I have simple sinatra script
require 'rubygems'
require 'sinatra'
get '/' do
%x[sleep.bat] #dos batch file that waits for 10sec
end
which simulates my real sintra script that calls ant script. The ant run can finish in an hour or so. I want to use my sinatra application while the ant run is running. But sinatra waits till the ant run finishes. Then it processes whatever requests I made meanwhile.
I use
Windows XP SP3
ruby 1.8.7 (2010-08-16 patchlevel 302) [i386-mingw32]
sinatra (1.2.6, 1.0)
and one rb file
Although a process that runs for an hour is really an entirely different situation, Rack applications are typically run with multiple app servers. This will allow you to make additional requests while your long-running call is busy.
You can run a Rack application under any of the typical ruby app servers. Passenger, Unicorn or Thin could all address your needs in this respect.
Related
I am creating a Perl script that creates a Net::WebSocket::Server on port 3000. Now I had the (not so brilliant) idea to start the script in the browser via CGI, so it runs in the background and can't be stopped. However, I have to restart the script whenever I modify it.
Is it possible to stop a CGI script in an endless loop, except by restarting the computer?
You didn't say what operating system you are on, so we cannot give you specific advice on how to find and kill the process. But you can always restart the web server application. CGI scripts are children of the server process (probably an Apache) that starts them. If you simply restart the Apache server, they should all be terminated.
Please don't put code that is supposed to run persistently in your cgi-bin directory. That's a bad idea, as you discovered.
Hello I experimenting some small things with Mojolicious and I have the following question:
What happens when a request is received ?
Is there some caching like in modperl or is the code compiled each time ?
It depends on the server it runs under.
If you use a pre-forking app server or fastcgi server then you'll get one or more processes re-used for multiple requests.
You can run a simple CGI, launching the script for each request, but it wouldn't be common.
Deployment options are in the manual.
Can someone explain the live cycle for a request in a Perl Dancer application starting from the server accepting the request. Does the application stay in memory like FCGI or does it have to be loaded for every request?
When using CGI, the application must be loaded with each request. FCGI, like you said, will keep the application running. Here's the lifecycle for CGI:
loads the perl runtime
loads necessary modules
configures the application
sets up all routes (not just the one needed)
finds the correct route and handles the request.
exits
When using FCGI steps 1-4 are done at load time. So if you are running with apache, when apache is started so is the perl runtime for your application. You are left with just step 5. Requests respond much faster when using FCGI.
Nowadays, many web shared webhosts support FastCGI, it's just a matter of configuring it correctly.
I need to launch a server script which will not exit. and after the server is ready I need to start the client code to run some automated tests.
tried, not work, the server process is not in the background and the client code cannot be executed.
system ($server &)
is it possible to use Parallel::ForkManager to handle this, how? all the examples are repetitive tasks, while my case is server and client.
Parallel::ForkManager isn't really designed for this; there are various other distributions for supporting what a server needs to do; Daemon::Daemonize looks like it does the fewest other things besides just running your designated server code in the background.
I want to deploy a PSGI scripts that runs in Apache2 with Plack. Apache is configured with:
<Location "/mypath">
SetHandler perl-script
PerlResponseHandler Plack::Handler::Apache2
PerlSetVar psgi_app /path/to/my/script.psgi
</Location>
When I test the script with plackup, the --reload parameter watches updates on the .psgi file. In the production environment it is fine that Apache and Plack do not check and restart on each change for performance reasons, but how can I tell them explicitly to restart Plack::Handler::Apache2 and/or the PSGI script to deploy a new version?
It looks like Plack regularly checks for some changes but I have no clue when. Moreover it seems to create multiple instances, so I sometimes get different versions of script.psgi when at /mypath. It would be helpful to manually flush perl response handler without having to restart Apache or to wait for an unknown amount of time.
The short answer is you can't. That's why we recommend you to use plackup (with -r) for quick development and use Apache only for deployment (production use).
The other option is have a development apache process, and set MaxRequestsPerChild to a really small value, so that you will get a fresh child spawned in a very short period of time. I haven't tested this, and doing so will definitely impact the performance of your entire httpd, if you run the non-development application running on the same process (which is a bad idea in the first place anyway).
Apache2::Reload (untested)
You can move your application out of the appache process,
e.g.
FastCgiExternalServer /virtual/filename/fcgi -socket /path/to/my/socket
an run your programm with
plackup -s FCGI --listen /path/to/my/socket --nproc 10 /path/to/my/script.psgi
This way you can restart your application without restarting apache.
if you save the pid of the main fcgi process (--pid $pid_file)
you can easyly restart an load your new code.
There is also a module avail to manage (start,stop, restart) all your fcgi pools:
https://metacpan.org/pod/FCGI::Engine::Manager::Server::Plackup (not tested)