[bbbbbbbbb]

huh?

- No Apache????

- why force a rather devish level PSGI module on all web applications???? oh, yeah, you've been advised by the guy who made the port...

  i've been using CGI::Fast under Apache for years and it has been working just PERFECTLY fine.
  Do not see the need to change especially when
  the PSGI doc is so badly written...
  At least the doc states that people who supports mod_perl/CGI::Fast will not see much benefit of switching to PSGI... 

- what is the Perl version?

[davecardwell]

5.12: https://gist.github.com/945834

[bbbbbbbbb]

thank you! recent version, that's a plus.

[perlgeek]

What's devish about PSGI? Seems like exactly the right choice for the task.

[bbbbbbbbb]

Like FastCGI is...

PSGI has been developed in 2009, then nothing for a long time (and as it hasn't spread as wild fire across providers i don't think there is enough real dev around it to assure that it is "stable" enough), now, a dev release, sure... the doc is unclear as to what it brings on the table, why it should be used, how to be used, the improvement it brings if any are really not clear... "you will be glad in the future..."...yeah, i need more than that to get people around me starting to use it.

FastCGI has been working for a long time, clear, easy and already "cross-server"...

All in all, the doc is a real problem and no hard evidence of it being used is, to some extend, an other.

[mst]

PSGI is not at the same level as FastCGI.

Nobody in their right mind has been using CGI::Fast directly for years - we've done it via adapters through e.g. Catalyst::Engine::FCGI for Catalyst and equivalents for other frameworks.

PSGI is just a means to present various HTTP bearing things to the app - in fact the FCGI.pm maintainers all now deploy their applications via Plack::Handler::FCGI.

All perl frameworks of note now have support for PSGI, and Catalyst is dumping its engine modules in favour of Catalyst::Engine::PSGI - we've been heavily involved in improving the Plack ecosystem to ensure that'll be a sane choice.

There's plenty of assurance that it's stable enough.

Go DotCloud for forward thinking choices here.

[bbbbbbbbb]

> Nobody in their right mind has been using CGI::Fast directly for years

Could you extend on that? Been using it for years,just works fine.

>PSGI is just a means to present various HTTP bearing things to the app

I really still don't get the benefit though. But perhaps I should dig into it more (for now, the python implementation doc was helpful but still did not bring me that much clues as to the real benefits about it)

[bulknews]

> the doc is unclear as to what it brings on the table, why it should be used, how to be used, the improvement it brings if any are really not clear.

I assume you're looking at the non-dev PSGI specification on CPAN. We're working on revising the documentation to upgrade the specification to 1.1, as well as improving the FAQ document.

Just to address your concern, I improved the part where it explains the benefits of switching to PSGI: https://github.com/miyagawa/psgi-specs/commit/e3e756cf1eebe8...

Also, for more generic overview and introduction of what PSGI is and why it is useful, take a look at my slides at OSCON 2010: http://www.slideshare.net/miyagawa/plack-at-oscon-2010

- miyagawa

[bbbbbbbbb]

Thank you for trying to sort it out.

> I assume you're looking at the non-dev PSGI specification

yes.

> PSGI specification on CPAN

Not really sure it is a good idea to put a spec on CPAN(I know you can find books on CPAN but I really do not think this is the right place for such matters but especially when PSGI/Plack confusion certainly exists.well, that just my view of things)...

Regarding your additions:

>You can stop writing code to support many web server environments.

As your slide shows, CGI.pm handles quite well many of the environment you list. It has been in development for more than 10years, updated very regularly to fix bugs, even browser based one, the doc is easy to read. The perl based server you list were built for PSGI in mind so you sell me some candies and the toothbrush that goes with it.

> Your framework can now use all of Plack middleware components.

session, caching,etc. All of these "middleware" already exists since a very long time. so it is just yet an other addition,an other way of doing it. Some of these PSGI middleware were extracted from Catalyst. Catalyst authors decided to create their own set of engine instead of choosing to use CGI.pm (unlike CGI::Application/Jifty building upon it), linking to your "gross." conclusion- in your slide.

> You can test the application using the consistent L<Plack::Test> interface.

WWW::Mechanize works like a charm for such matters. (perhaps your Plack::Test differs though, did not look into it so this might be a valid point)

Regarding your slide:

The diagram you show is at best simplistic, at worst wrong (factcgi->lighttpd). It deviates from reality to get to your point.

I find the "CGI.pm? meh" slide very disrespectful and all by itself shows the ambient snobbish attitude towards this very useful module(inherited from the Catalyst community mindset?)

so all in all, I still don't get the problem it is trying to solve(stealing from python you wrote. an other language, an other culture, an other context) I still don't get the benefit out of it and why I should use it.

I think I am a lost cause^^; I am sorry. It's not that I am against new things but here, I really don't get the advantage of this spec and everything that goes around. I have a bootstrap package that launches the FastCGI run loop then delegates to modules that do there job and print the resulting body at the very end (it's a MVC like framework,nothing fancy) so I don't think it would hurt much to add support for this but I won't do so as long as I don't get a real + in doing so.

Using Nginx is not much of a matter. (Nginx+FastCGI should be fine)

[bulknews]

> Not really sure it is a good idea to put a spec on CPAN

They are also available on github with POD markup, with the full version controlled history: https://github.com/miyagawa/psgi-specs

> CGI.pm handles quite well many of the environment you list. It has been in development for more than 10years, updated very regularly to fix bugs, even browser based one, the doc is easy to read.

Yes, that's why I collaborated with CGI.pm authors and maintainers (Lincoln Stein and Mark Stosberg) from day 1 - like the possibility to include PSGI support directly into CGI.pm, which ended up in an extension module i co-authored with CGI.pm maintainers and put up on CPAN as CGI::PSGI, the CGI.pm compatible interface. T

There's also CGI::Emulate::PSGI which allows to write any CGI scripts unmodified under the PSGI environment.

> session, caching,etc. All of these "middleware" already exists since a very long time. so it is just yet an other addition,an other way of doing it.

It's not just an "addition" - if there are N frameworks, the caching modules need to be written and maintained for N frameworks - with PSGI unification, it should be written once and tested and maintained once - that way we can avoid duplicate efforts to fix bugs and make improvements, etc.

> Catalyst authors decided to create their own set of engine instead of choosing to use CGI.pm (unlike CGI::Application/Jifty building upon it)

and the upcoming Catalyst 5.9 removes all engines in favor of PSGI/Plack interface, like Jifty did a while ago.

> WWW::Mechanize works like a charm for such matters. (perhaps your Plack::Test differs though, did not look into it so this might be a valid point)

That's why there's Test::WWW::Mechanize::PSGI exists - you can run the exactly same test against a live server as well as in-process testing through the PSGI interface.

[bbbbbbbbb]

>They are also available on github

Great. perhaps getting rid of it on CPAN could be nice.

> It's not just an "addition" - if there are N frameworks, the caching modules need to be written and maintained for N frameworks

I can not agree with that point. You are almost forgetting CPAN here-which is funny coming from you- (The strength of Perl that many languages do not even dream to have)... The actual modules were context agnostic and it's not because you have N frameworks that you MUST have N xxx(caching,session) frameworks. It's just that some framework authors want to reinvent the wheel.no more, no less(in other languages, without an infrastructure like CPAN this can happen more than it ought to, indeed!).

so the logic: N web framework = N xxx sub frameworks is just biased. It has always been possible to not duplicate efforts, avoid bugs with different code trying to solve the same problem. It's just that again, some framework did reinvent the wheel where they should have been using what already works (or help on it).

> That's why there's Test::WWW::Mechanize::PSGI exists

you are just telling me that there is yet an other way of doing the same thing but in the PSGI environment.

All in all, I still don't see what the PSGI spec/protocol and the modules that evolute around bring to the environment. I don't see why we should have a superset of CGI,which is a language agnostic protocol,that binds with Perl via PSGI. Really don't get the idea...Is this binding between Perl and the protocol lead to way much better performance?(better than FastCGI?)

I've never used mod_perl as it is only useful for Apache but I knew that using FastCGI could open me many servers and better performance without having to change much and care about even the language.

I guess my environment is too far from the problems you seem to encounter and fix.

They are new things where I think, yes, this is going to be good but here, the "pintokita" moment does not arrive at all.

I can only hope that DotCloud will offer a simple support for fastCGI (CGI::Fast) with Nginx.

By the way, adding some script examples for CGI::PSGI and other related modules would be much appreciated (The doc is too elliptic and assume we know already that much about the PSGI context and Plack system)

Thank you for your time and efforts anyhow!

[shykes]

We expect our choice of stack to be transparent for all developers. If it turns out it's the wrong choice, we'll either switch to Apache, or at least support both.

So far all alpha testers seemed very happy :)

[bbbbbbbbb]

Well, I got the invitation and while playing around with nodejs, I was really looking forward for Perl support but this is absolutely not the environment I want to work on (wanted to use an in-house framework, not the ones listed and see if DotCloud could be of use for our clients).

To tell the truth, this could be a good occasion to try to make the in-house app works in such environment but

1- don't see any real benefit

2- don't want to decipher the doc

3- no time (will have to work extra hours)

you should definitely support both environment and not base your choice on the sole feedback of one person (you know... TMTOWTDI)

[jpetazzo]

Hi,

Well, actually, we didn't pickup Plack from its author. When people started asking about Perl, we just replied with another question: "which framework? how? what?", and we tried extract the most common denominator.

The vast majority told us about Mojolicious, Dancer and Catalyst. There seemed to be a pattern :-)

Regarding the server interface, a lot of people seems to agree over Plack. We were the ones asking "hey, what about FastCGI?" - since I personally never had met Plack before. We were shown the Plack::*::FCGI modules and thought "okay, that seems cool".

Then we had a look at the server options. We had already used UWSGI for the Python stack, and UWSGI has a PSGI module. Some might say that it's a bit experimental, but the authors are awesome people, always willing to fix bugs as fast and efficiently as possible.

Of course, the author of Plack helped us to get everything straight - but paradoxally, he was also the one pointing us to cpanm, perlbrew and basic stuff like Makefile.PL.

Now, to get back to you: what does your app look like? We would like to help and see how we can get it to run on DotCloud!

[bbbbbbbbb]

Dancer and Mojolicious are pretty new and I will not use them in production yet (not to say that our framework is better, way from that but just that it's not open to things like that: http://blog.kraih.com/mojolicious-116-emergency-release-plea...). Catalyst is a dependency hell made true,not for us either. Mojolicious and Dancer will certainly be nice and will look into it but not at this stage of development.

>Some might say that it's a bit experimental,

Because it is.

It's nice to play with it though. But not quite yet to use for our clients.

> but the authors are awesome people, always willing to fix bugs as fast and efficiently as possible.

Won't be able to say to my client: well, you know, we've tried this experimental stuff but we met these bugs we can't do anything about.

"hey, what about FastCGI?"

This was a very good question and I would have answered go for it... Apache+FastCGI+CGI::Fast. That's quite common nowadays and I think well understood, well documented.

cpanm is not necessary, I've never used it and am happy with cpan. oh, right, cpanm is by the same author right?

perlbrew&locale::lib are nice things to have though.

> We would like to help and see how we can get it to run on DotCloud!

Apache+FastCGI+CGI::Fast,that will do for me.

Apache+mod_perl,that will do (even though i don't use it).

Having at the cutting edge technologies is nice, don't get me wrong but it would help to have at least a more stable or at least bullet-proof environment too.

[mst]

If you have a problem with Catalyst dependencies, please report them to irc.perl.org #catalyst (I'm mst on there).

Any time anybody reports a problem with them, we go out of our way to solve it - avoiding wheel reinvention is important to us to speed development but we understand that using a module makes us responsible for it installing for end users.

if you really want CGI.pm, there are Plack modules to convert a PSGI environment to a CGI environment - descended roughly from the Catalyst::Controller::WrapCGI that Opsview sponsored Shadowcat to write years ago.

And remember, PSGI might appear to be new but much of the guts of Plack are pulled from previous framework-specific code so the various workarounds for server insanities are already there. It's a lot more reliable than you appear to think.

[bbbbbbbbb]

>PSGI might appear to be new but much of the guts of Plack are pulled from previous framework-specific code so the various workarounds for server insanities are already there. It's a lot more reliable than you appear to think.

I see. Perhaps my vision of the state of PSGI is not right indeed. Nethertheless, my apps run under Fast::CGI and I really don't see the advantage of PSGI.

[whiskeyjack]

I resepectfully disagree. My company has two PSGI Dancer apps running mission critical elements. They're "new" but they're absolutely production ready. Plack/PSGI has been embraced by almost everyone.

I'm REALLY looking forward to playing with DotCloud.

Plack/PSGI is not "cutting edge". It's the way to do it now, not tomorrow. You do Miyagawa a disservice implying he's pumping his own code.

[nmcfarl]

Likewise my company is 100% PSGI for the last year+, we're a mix of a good number of Catalyst and Dancer apps. We've had absolutely 0 problems here.

PSGI stable, sane and the way you want to be doing things.

[bbbbbbbbb]

>Plack/PSGI has been embraced by almost everyone.

In your company or in general? Because if it's in general, I would be more than happy to see where you get your stats.

> You do Miyagawa a disservice implying he's pumping his own code.

Well, I do think that a not even 2yo spec,a set of modules that are 6~18 months old pushed on a cloud service like that with no back up plan for more "traditional" systems is a way to push its own system. we can agree to disagree on that. which percentage of providers offer plack with nginx nowadays compared to Apache with FactCGI?

[bbbbbbbbb]

By the way, I see that you've decided to go with Nginx as the primary server for all languages and this is not really a problem in fact. I don't think switching to Nginx would be much of a hassle.