Re: PerlModule hell - questions and comments
Kee Hinckley wrote:
At 4:18 PM -0500 3/22/02, Perrin Harkins wrote:
Modules loaded with PerlModule and PerlRequire are not supposed to be
loaded again the second time. I seem to remember that they are loaded
again when using DSO though, so if you're using DSO you may want to
recompile as static. Also, if you have PerlFreshRestart on that will
cause a reload.
If all you were doing was loading a normal Perl module, the single load
would be fine. The catch is that in this case we are loading a Perl
module which in turn is registering an Apache module. The Apache module
is being *unloaded* prior to the second pass through the config file.
The only way that it will be reloaded is if the Perl module is reloaded
on the second pass as well.
If all you want to do is to be able to load the module only during the
restart use in startup.pl:
if ($Apache::Server::ReStarting) {
require My::Sensitive::Module;
}
--
__
Stas BekmanJAm_pH -- Just Another mod_perl Hacker
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Re: PerlModule hell - questions and comments
At 7:04 PM +0800 3/23/02, Stas Bekman wrote:
If all you want to do is to be able to load the module only during
the restart use in startup.pl:
if ($Apache::Server::ReStarting) {
require My::Sensitive::Module;
}
No, the module has to be loaded during both phases, other wise the
configuration file syntax extensions it adds won't be loaded. The
sequence is:
1. Module loads
2. On load, module registers as an Apache module
3. On the second parse of the config file, apache asks module to unload
4. Perl module unregisters itself
5. Module isn't reloaded (because perl modules get loaded only once)
6. Apache module doesn't get reloaded
7. Config file parse fails with syntax errors
You would think that I could just skip step #4, but as far as I can
tell that leaves stale pointers around, at least on some
platforms/configurations. It also doesn't seem proper in general.
The only work-around I have is to add an perl section that calls
the initialization manually. That works, but one would hope that
Perl modules could be treated as first-class Apache modules with
extra magic in the config file.
BTW. I thought that startup.pl was only called once, so your
suggestion would only work inside a perl directive anyway?
--
Kee Hinckley - Somewhere.Com, LLC
http://consulting.somewhere.com/
[EMAIL PROTECTED]
I'm not sure which upsets me more: that people are so unwilling to accept
responsibility for their own actions, or that they are so eager to regulate
everyone else's.
Re: PerlModule hell - questions and comments
Kee Hinckley wrote: 1. *Why* are the apache config files executed twice (completely with loading and unloading all the modules)? This is a core apache thing. Apache does it to verify that a restart is safe. See http://thingy.kcilink.com/modperlguide/config/Apache_Restarts_Twice_On_Start.html I'm not saying I think it's the greatest idea, but that's the reason behind it. Modules loaded with PerlModule and PerlRequire are not supposed to be loaded again the second time. I seem to remember that they are loaded again when using DSO though, so if you're using DSO you may want to recompile as static. Also, if you have PerlFreshRestart on that will cause a reload. A couple of people reported a bug that they were seeing which caused these modules to be loaded twice anyway. That sounds like the issue you saw with Perl sections. I haven't tested this myself, and fixing it would probably require help from Doug. As a workaround, it is possible to do all of your module loading from a startup.pl called from PerlRequire, and avoid that problem. That's what I do. Of course my goal here sounds like exactly the opposite of yours: you actually *want* Embperl to get loaded both times so that your conf directives will work. I haven't run into that problem before because I don't use any modules that add conf directives. Maybe Gerald will have an explanation of what the expected behavior is on his end. It can't be this much trouble for most people or no one would be using Embperl or custom conf directives. - Perrin
Re: PerlModule hell - questions and comments
At 4:18 PM -0500 3/22/02, Perrin Harkins wrote: Modules loaded with PerlModule and PerlRequire are not supposed to be loaded again the second time. I seem to remember that they are loaded again when using DSO though, so if you're using DSO you may want to recompile as static. Also, if you have PerlFreshRestart on that will cause a reload. If all you were doing was loading a normal Perl module, the single load would be fine. The catch is that in this case we are loading a Perl module which in turn is registering an Apache module. The Apache module is being *unloaded* prior to the second pass through the config file. The only way that it will be reloaded is if the Perl module is reloaded on the second pass as well. A couple of people reported a bug that they were seeing which caused these modules to be loaded twice anyway. That sounds like the issue you saw with Perl sections. I haven't tested this myself, and fixing it would probably require help from Doug. As a workaround, it is possible to do all of your module loading from a startup.pl called from PerlRequire, and avoid that problem. That's what I do. That doesn't solve the problem because it won't load twice, and the Apache module won't get reloaded. because I don't use any modules that add conf directives. Maybe Gerald will have an explanation of what the expected behavior is on his end. It can't be this much trouble for most people or no one would be using Embperl or custom conf directives. At Embperl 2.0b6 Gerald switched to a new architecture. The previous version was just a plain Perl module loaded as a handler by mod_perl. This version is also an Apache module. Maybe we need an option for PerlModule that forces a load each time? -- Kee Hinckley - Somewhere.Com, LLC http://consulting.somewhere.com/ [EMAIL PROTECTED] I'm not sure which upsets me more: that people are so unwilling to accept responsibility for their own actions, or that they are so eager to regulate everyone else's.
Re: PerlModule hell - questions and comments
Kee Hinckley wrote: At Embperl 2.0b6 Gerald switched to a new architecture. The previous version was just a plain Perl module loaded as a handler by mod_perl. This version is also an Apache module. Okay, if it's only in the recent betas then it's possible that only a few people have encountered this. Can anyone else who has built a module with custom conf directives comment on this issue? Maybe we need an option for PerlModule that forces a load each time? It seems like something to keep the C and perl sides doing the same thing is what's needed, so that if the C stuff gets unloaded the perl stuff will too. In your case, PerlFreshRestart might help with what you're trying to do since it will clear %INC, but you may still have the problem with needing to call Init. - Perrin
Re: PerlModule hell - questions and comments
At 5:11 PM -0500 3/22/02, Perrin Harkins wrote: Kee Hinckley wrote: At Embperl 2.0b6 Gerald switched to a new architecture. The previous version was just a plain Perl module loaded as a handler by mod_perl. This version is also an Apache module. Okay, if it's only in the recent betas then it's possible that only a few people have encountered this. Can anyone else who has built a module with custom conf directives comment on this issue? I should note that it also appears to be at least partially either an architecture or configuration issue. The original code which worked for Gerald didn't call unload in its cleanup handler. However that did not work on my system (MacOS X), and on at least one other system (Linux). I found that I had to call unload for things to work, and then it wasn't getting it reloaded. So there may be another way to fix the problem. Suggestions are more than welcome. -- Kee Hinckley - Somewhere.Com, LLC http://consulting.somewhere.com/ [EMAIL PROTECTED] I'm not sure which upsets me more: that people are so unwilling to accept responsibility for their own actions, or that they are so eager to regulate everyone else's.
Re: PerlModule hell - questions and comments
At 5:11 PM -0500 3/22/02, Perrin Harkins wrote: In your case, PerlFreshRestart might help with what you're trying to do since it will clear %INC, but you may still have the problem with needing to call Init. PerlFreshRestart will reload the module and thus call Init, but PerlFreshRestart is only called when we fork a new process, it is not called between the first and second parsing of the config file at startup. That seems like a bug to me. If reading the config file twice is intended to ensure that subsequent re-reads on HUP will work, then *everything* should be the same, and that means if PerlFreshRestart is set, it ought to happen there as well. Oddly enough though, PerlFreshRestart is not required for this to work after a HUP, even though it would seem to make sense. Looking at my debug output, it appears that -HUP doesn't cause the cleanup handlers to be called, so the module is never unloaded. -- Kee Hinckley - Somewhere.Com, LLC http://consulting.somewhere.com/ [EMAIL PROTECTED] I'm not sure which upsets me more: that people are so unwilling to accept responsibility for their own actions, or that they are so eager to regulate everyone else's.
