This sounds like a good solution - I will have a play with it. Being a bit lazy, what would be the setting for a "run once, straightaway" entry in the crontab?
On Jan 27, 10:44 pm, achipa <attila.cs...@gmail.com> wrote: > We have internal cron functionality since not so long ago, which > allows us to schedule execution of 3rd party scripts, web2py > environment wrapped scripts (this is "web2py -S app -M -R private/ > script.py" ) and controller functions. Each app has it's own cron > settings (check applications/cron/crontab for examples), so startup > scripts won't be tripping over each other (you can have your own > applications/myapp/cron/crontab). So, since cron is already > initializing itself and reading the crontabs at the first possible > time regardless of how it's run (wsgi,(f)cgi,cherrypy), it might as > well run your application init script. You could just add a line in > the format I mentioned above and that's it. I got the idea when > massimo said web2py -S -M -R since that is roughly also what I use to > wrap stuff I'm starting from cron. > > PS. If crontab sounds like a Hungarian curse to you, take a look* > athttp://en.wikipedia.org/wiki/Cron#Usage > > *Web2py cron just *mimicks* crontab, so it should work on all > platforms without additional daemons - even if you're on windows or on > a mac, it's still a go. > > On Jan 27, 8:59 pm, billf <billferr...@blueyonder.co.uk> wrote: > > > achipa > > > sorry that just sailed over my head. how would that work? what could > > it do? > > > Bill > > > On Jan 27, 7:47 pm, achipa <attila.cs...@gmail.com> wrote: > > > > Just a thought - we could hook an application level startup script (or > > > controller function) into cron. As cron already takes care of cgi/ > > > fastcgi/wsgi/cherrypy, timings and some threading peculiarities it > > > shouldn't be too hard to integrate. How do you feel about that ? > > > > -1 * * * * * web2py *applications/myapp/private/script.py > > > > billf wrote: > > > > My original question was about app-level configuration - I maybe > > > > confused things by my post #3. The plugin stuff is really a separate > > > > tho' related thread. > > > > > Re Massimo's post re "web2py -S app -M -R private/script.py" > > > > > How does this work if you have an instance of web2py with several > > > > active applications? I suppose it wouldn't be bad to just include a > > > > line (in private/script.py) for each application, e.g. for app "bill" > > > > run script X, for app "Tim" run script Y. > > > > > If you used this approach and wanted to change the config for app > > > > "bill" (script X) would you have to restart web2py or could you just > > > > run script X? > > > > > On Jan 27, 6:09 pm, Timothy Farrell <tfarr...@swgen.com> wrote: > > > > > I think you're misunderstanding. We're talking about the database > > > > > driver code that Bill coded together. This has nothing to do with any > > > > > particular app. Rather how and when sql.py starts up. > > > > > > mdipierro wrote: > > > > > > I oppose any initialization that is not at the app level. It would > > > > > > introduces hidden dependencies in the apps. > > > > > > > Massimo > > > > > > > On Jan 27, 12:01 pm, Timothy Farrell <tfarr...@swgen.com> wrote: > > > > > > >> I didn't think we were talking on the app level. > > > > > > >> mdipierro wrote: > > > > > > >>> I am skeptical about initialization code being initialized by the > > > > > >>> app > > > > > >>> because it may take time and web server may kill it. > > > > > > >>> My approach is to create an initialization script in private and > > > > > >>> run > > > > > >>> it with > > > > > > >>> web2py -S app -M -R private/script.py > > > > > > >>> On Jan 27, 10:24 am, Timothy Farrell <tfarr...@swgen.com> wrote: > > > > > > >>>> Yes, but WSGI/FCGI web-servers always have several new processes > > > > > >>>> ready > > > > > >>>> for requests rather than having to wait for a process to start > > > > > >>>> as soon > > > > > >>>> as a request is received. > > > > > > >>>> Be careful about the multiple processes thing. Separate > > > > > >>>> processes can > > > > > >>>> import the same module and not be sharing data or code because > > > > > >>>> they are > > > > > >>>> run under two separate interpreters in two separate processes. > > > > > >>>> You only > > > > > >>>> have to worry about this type of sharing with shared resources > > > > > >>>> like files. > > > > > > >>>> It seems that you're suggesting one interpreter process should > > > > > >>>> parse the > > > > > >>>> available plugins and provide that data to other interpreter > > > > > >>>> process. > > > > > >>>> Now this could work with threads, but inter-process > > > > > >>>> communication is > > > > > >>>> much more complicated and may take longer than it would for each > > > > > >>>> process > > > > > >>>> to just parse it's own set of plugins. > > > > > > >>>> -tim > > > > > > >>>> achipa wrote: > > > > > > >>>>> One itsy-bitsy note about the persistence of > > > > > >>>>> WSGI/FCGI/standalone - > > > > > >>>>> out of these, only the standalone has serious persistence. WSGI > > > > > >>>>> and > > > > > >>>>> FCGI can (and will) get restarted on the web server's whim (some > > > > > >>>>> webservers come with a predefined number of requests after > > > > > >>>>> which they > > > > > >>>>> restart the process, just in case). Also, with WSGI and FCGI > > > > > >>>>> you can > > > > > >>>>> have several parallel processes, which again complicates things > > > > > >>>>> (do > > > > > >>>>> you consider a second process starting a first load or can it > > > > > >>>>> re-use > > > > > >>>>> the results of the first one's startup ? It really depends on > > > > > >>>>> the > > > > > >>>>> usage scenario). > > > > > > >>>>> As for main.wsgibase(), my bad, I wanted to say 'when' not > > > > > >>>>> 'where'. > > > > > > >>>>> On Jan 27, 4:35 pm, Timothy Farrell <tfarr...@swgen.com> wrote: > > > > > > >>>>>> I think you're confusing things.... see below > > > > > > >>>>>> achipa wrote: > > > > > > >>>>>>> The problem is that first start is a very relative term > > > > > >>>>>>> depending on > > > > > >>>>>>> how you run web2py, it's not the same for > > > > > >>>>>>> standalone/cherrypy, CGI, > > > > > >>>>>>> MOD_WSGI, parallel versions of these, etc. > > > > > > >>>>>> Correct...sorta. We really have three categories here, threaded > > > > > >>>>>> persistent python interpreter, persistent distinct processes > > > > > >>>>>> and > > > > > >>>>>> (non-persistent) distinct processes. The third scenario is > > > > > >>>>>> vanilla > > > > > >>>>>> CGI. The core of web2py is started for every request with > > > > > >>>>>> plain CGI. > > > > > >>>>>> However WSGI, FCGI and the standalone setups use some > > > > > >>>>>> variation of the > > > > > >>>>>> other two setups in which case imported modules are not rerun. > > > > > >>>>>> (Google > > > > > >>>>>> agrees...http://code.google.com/appengine/docs/python/runtime.html#App_Caching)> > > > > > >>>>>> This means that your > > > > > > >>>>>>> startup code could be executed in a whole lot of places, not > > > > > >>>>>>> always > > > > > >>>>>>> where you want it. You also have to make arrangements for race > > > > > >>>>>>> conditions (what if a web request comes in while you are > > > > > >>>>>>> executing > > > > > >>>>>>> your startup function?) > > > > > > >>>>>> This part is only true if your code is in the page processing > > > > > >>>>>> path (i.e. > > > > > >>>>>> main.wsgibase() ). If your code is in an imported module it > > > > > >>>>>> will only > > > > > >>>>>> be run once per executed process.> As an idea, you might want > > > > > >>>>>> to check/set a flag variable in cache.ram. > > > > > > >>>>>>> If you don't see that flag, presume it's a first start, if it > > > > > >>>>>>> is > > > > > >>>>>>> there, consider yourself loaded. This also can lead to a few > > > > > >>>>>>> gotcha's > > > > > >>>>>>> (use mutexes to prevent race conditions) and doesn't work > > > > > >>>>>>> with CGI, > > > > > >>>>>>> but until somebody suggests something better, it might be > > > > > >>>>>>> worth a try. > > > > > > >>>>>> This is a good point. If you're module has module static > > > > > >>>>>> variables then > > > > > >>>>>> those variables could be accessed from multiple threads and > > > > > >>>>>> hence would > > > > > >>>>>> need to be protected with a lock-type. To see an example of > > > > > >>>>>> this, the > > > > > >>>>>> cache module has "meta_storage" that holds cached information > > > > > >>>>>> and is > > > > > >>>>>> thread-safe. > > > > > > >>>>>> -tim > > > > > > >>>>>>> On Jan 27, 5:44 am, billf <billferr...@blueyonder.co.uk> > > > > > >>>>>>> wrote: > > > > > > >>>>>>>> Basically, is there any code that receives control when an > > > > > >>>>>>>> application > > > > > >>>>>>>> first starts that allows some initialisation/configuration > > > > > >>>>>>>> that > > > > > >>>>>>>> doesn't have to run after every request? > > > > > > >>>>>>>> I believe code could be put in db.py but that is not ideal > > > > > >>>>>>>> conceptually - and would run on every request? > > > > > > >>>>>>>> I can see that there are pros and cons to the idea of "on > > > > > >>>>>>>> start" code > > > > > >>>>>>>> and would be interested in peoples' views. > > > > > > >>>>>> -- > > > > > >>>>>> Timothy Farrell <tfarr...@swgen.com> > > > > > >>>>>> Computer Guy > > > > > >>>>>> Statewide General Insurance Agency (www.swgen.com) > > > > > > >>>> -- > > > > > >>>> Timothy Farrell <tfarr...@swgen.com> > > > > > >>>> Computer Guy > > > > > >>>> Statewide General Insurance Agency (www.swgen.com) > > > > > > >> -- > > > > > >> Timothy Farrell <tfarr...@swgen.com> > > > > > >> Computer Guy > > > > > >> Statewide General Insurance Agency (www.swgen.com) > > > > > > -- > > > > > Timothy Farrell <tfarr...@swgen.com> > > > > > Computer Guy > > > > > Statewide General Insurance Agency (www.swgen.com) --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "web2py Web Framework" group. 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