|
PLP - Perl in HTML pages |
PLP - Perl in HTML pages
<Files *.plp>
SetHandler perl-script
PerlHandler PLP
PerlSendHeader On
PerlSetVar PLPcache On
</Files>
# Who said CGI was easier to set up? :)
#!/usr/bin/perl
use PLP;
PLP::everything();
ScriptAlias /foo/bar/ /PLP_COMMON/
<Directory /foo/bar/>
AllowOverride None
Options +ExecCGI
Order allow,deny
Allow from all
</Directory>
AddHandler plp-document plp
Action plp-document /PLP_COMMON/plp.cgi
<html><body>
<:
print "Hurrah, it works!<br>" for 1..10;
:>
</body></html>
PLP is yet another Perl embedder, primarily for HTML documents. Unlike with other Perl embedders, there is no need to learn a meta-syntax or object model: one can just use the normal Perl constructs. PLP runs under mod_perl for speeds comparable to those of PHP, but can also be run as a CGI script.
<: perl_code(); :><: and :>, you can add Perl code to your document. This is
what PLP is all about. All code outside of these tags is printed. It is
possible to mix perl language constructs with normal HTML parts of the document:
<: unless ($ENV{REMOTE_USER}) { :>
You are not logged in.
<: } :>
:> always stops a code block, even when it is found in a string literal.
<:= $expression :><: and the equal sign.
foo <:= $bar :> $baz is like <: print 'foo ', $bar, ' baz'; :>.
<(filename)><( foo.txt)>
includes the file named foo.txt, including the space in its name. A
compile-time alternative is include(), which is described in the PLP::Functions manpage.
These are described in the PLP::Functions manpage.
/foo.plp)
/var/www/index.plp)
On is default, anything that isn't =~ /^off$/i is considered On.
Not only syntax is important, you should also be aware of some other important
features. Your script runs inside the package PLP::Script and shouldn't
leave it. This is because when your script ends, all global variables in the
PLP::Script package are destroyed, which is very important if you run under
mod_perl (they would retain their values if they weren't explicitly destroyed).
Until your first output, you are printing to a tied filehandle PLPOUT. On
first output, headers are sent to the browser and STDOUT is selected for
efficiency. To set headers, you must assign to $header{ $header_name} before
any output. This means the opening <: have to be the first characters in
your document, without any whitespace in front of them. If you start output and
try to set headers later, an error message will appear telling you on which
line your output started. An alternative way of setting headers is using Perl's
BEGIN blocks. BEGIN blocks are executed as soon as possible, before anything
else.
Because the interpreter that mod_perl uses never ends, END { } blocks won't
work properly. You should use PLP_END { }; instead. Note that this is a not
a built-in construct, so it needs proper termination with a semi-colon (as do
<eval> and <do>).
Under mod_perl, modules are loaded only once. A good modular design can improve performance because of this, but you will have to reload the modules yourself when there are newer versions.
The special hashes are tied hashes and do not always behave the way you expect, especially when mixed with modules that expect normal CGI environments, like CGI.pm. Read the PLP::Fields manpage for information more about this.
A lot of questions are asked often, so before asking yours, please read the FAQ at the PLP::FAQ manpage. Some examples can be found at the PLP::HowTo manpage.
No warranty, no guarantees. Use PLP at your own risk, as I disclaim all responsibility.
Currently maintained by Mischa POSLAWSKY <perl@shiar.org>
Originally by Juerd Waalboer <juerd@cpan.org>
the PLP::Functions manpage, the PLP::Fields manpage, the PLP::FAQ manpage, the PLP::HowTo manpage
|
PLP - Perl in HTML pages |