embedding python in HTML

[John Salerno]

I'm hoping someone can give me the basics for how to do very simple
things with Python scripts from within my HTML. For example, I know that
I can do this in PHP:

<h1>Here is a header</h1>
<?php include("file.h tml"); ?> // include some external html
<p>More html</p>

So to do this with Python, do I simply integrate it into the HTML as
above, with no extra steps? Also, which symbols do I use to denote
Python language?

Thanks.

[John Salerno]

Re: embedding python in HTML

John Salerno wrote:[color=blue]
> I'm hoping someone can give me the basics for how to do very simple
> things with Python scripts from within my HTML. For example, I know that
> I can do this in PHP:
>
> <h1>Here is a header</h1>
> <?php include("file.h tml"); ?> // include some external html
> <p>More html</p>
>
> So to do this with Python, do I simply integrate it into the HTML as
> above, with no extra steps? Also, which symbols do I use to denote
> Python language?
>
> Thanks.[/color]

Also, do I need to give the html file an extension of .py?

[Rene Pijlman]

Re: embedding python in HTML

John Salerno:
[Python alternative for PHP][color=blue]
>So to do this with Python, do I simply integrate it into the HTML as
>above, with no extra steps?[/color]

You'd need something like the PHP engine, that understands Python rather
than PHP.

I've used Cheetah:

http://www.cheetahtemplate.org/

Our BDFL seems to prefer Django:

http://www.artima.com/weblogs/viewpost.jsp?thread=146606

There's also PSP:

http://www.ciobriefings.com/psp/

And many more:

http://wiki.python.org/moin/WebProgramming

--
René Pijlman

[John Salerno]

Re: embedding python in HTML

Rene Pijlman wrote:[color=blue]
> John Salerno:
> [Python alternative for PHP][color=green]
>> So to do this with Python, do I simply integrate it into the HTML as
>> above, with no extra steps?[/color]
>
> You'd need something like the PHP engine, that understands Python rather
> than PHP.[/color]

My web server can run Python, fortunately. Now that they've turned it on
for me, I wanted to try it out, but I didn't know how to go about
writing a bit of code to stick into an HTML file.

[Paul Boddie]

Re: embedding python in HTML

Rene Pijlman wrote:[color=blue]
> John Salerno:
> [Python alternative for PHP][color=green]
> >So to do this with Python, do I simply integrate it into the HTML as
> >above, with no extra steps?[/color]
>
> You'd need something like the PHP engine, that understands Python rather
> than PHP.[/color]

[...]
[color=blue]
> There's also PSP:
> http://www.ciobriefings.com/psp/[/color]

For "straight Python Server Pages" without advertising various (and
possibly quite different) technologies, take a look at mod_python's
implementation:

http://www.modpython.org/

http://www.modpython.org/live/current/doc-html/pyapi-psp.html

I haven't actually used this particular implementation - I'm not a fan
of embedding programming languages in HTML - but I imagine that it's
one of the more actively developed projects of its kind.

Paul

[bruno at modulix]

Re: embedding python in HTML

John Salerno wrote:[color=blue]
> Rene Pijlman wrote:
>[color=green]
>> John Salerno:
>> [Python alternative for PHP]
>>[color=darkred]
>>> So to do this with Python, do I simply integrate it into the HTML as
>>> above, with no extra steps?[/color]
>>
>>
>> You'd need something like the PHP engine, that understands Python rather
>> than PHP.[/color]
>
>
> My web server can run Python, fortunately. Now that they've turned it on
> for me, I wanted to try it out, but I didn't know how to go about
> writing a bit of code to stick into an HTML file.[/color]

You've got to understand that Python is *not* a 'ServerPage' language
(-> php, asp, jsp etc) in itself. Your server can now run python, fine,
but *how* ? CGI ? FastCGI ? mod_python ? other ? (hint: it's probably
just plain old CGI...)


--
bruno desthuilliers
python -c "print '@'.join(['.'.join([w[::-1] for w in p.split('.')]) for
p in 'onurb@xiludom. gro'.split('@')])"

[John Salerno]

Re: embedding python in HTML

bruno at modulix wrote:
[color=blue]
> You've got to understand that Python is *not* a 'ServerPage' language
> (-> php, asp, jsp etc) in itself. Your server can now run python, fine,
> but *how* ? CGI ? FastCGI ? mod_python ? other ? (hint: it's probably
> just plain old CGI...)[/color]

So does that mean I need to have something further on the server? Or is
this something I can do on my end? How do I find out what I need?

[Kirk McDonald]

Re: embedding python in HTML

John Salerno wrote:[color=blue]
> bruno at modulix wrote:
>[color=green]
>> You've got to understand that Python is *not* a 'ServerPage' language
>> (-> php, asp, jsp etc) in itself. Your server can now run python, fine,
>> but *how* ? CGI ? FastCGI ? mod_python ? other ? (hint: it's probably
>> just plain old CGI...)[/color]
>
>
> So does that mean I need to have something further on the server? Or is
> this something I can do on my end? How do I find out what I need?[/color]

If you really want to use Python as a server page language, mod_python
has support for Python Server Pages via its PSP handler:

Python Server Pages:

http://modpython.org/live/current/doc-html/pyapi-psp.html

PSP handler:

http://modpython.org/live/current/doc-html/hand-psp.html

This of course means your server needs to have mod_python installed and
configured. (Consult your server administrator.) However, I've always
found PSP to be somewhat fiddly, and mixing any serious code with the
HTML text is hardly pretty.

A more common (and bare-metal) approach is CGI. In CGI, a request for a
page runs a script, the output of which is the HTML page. I think this
only requires that the server has Python installed, which you have said
is the case. Python has signifigant standard library support for writing
CGI.

You should examine Python's standard cgi module:
http://python.org/doc/2.4.2/lib/module-cgi.html
That page also has some nice examples to get you started.

And maybe its Cookie module, if you ever feel like messing with cookies:
http://python.org/doc/2.4.2/lib/module-Cookie.html

Slightly less bare-metal is using mod_python directly (rather than via
its PSP module). This is probably preferable to plain CGI if mod_python
is available, as it caches scripts as long as they are not changed. This
is faster than reading them off the disk every time. By and large,
mod_python's API replaces (or at least wraps) the standard library's CGI
support if you go this route. Again, this is only available if your
server has mod_python installed, which may or may not be the case.

[John Salerno]

Re: embedding python in HTML

Kirk McDonald wrote:
[color=blue]
> A more common (and bare-metal) approach is CGI. In CGI, a request for a
> page runs a script, the output of which is the HTML page. I think this
> only requires that the server has Python installed, which you have said
> is the case. Python has signifigant standard library support for writing
> CGI.[/color]

Thanks, that makes much more sense to me now. But does this mean I can
still write HTML normally? What would an example be of having HTML
within a Python script? I have a hard time picturing this, because I
imagine that most of my pages will be almost all HTML, with just a bit
of Python here and there, perhaps to insert headers and footers. Is all
the HTML just wrapped in a big print statement, or something like that?

[Georg Brandl]

Re: embedding python in HTML

John Salerno wrote:[color=blue]
> Kirk McDonald wrote:
>[color=green]
>> A more common (and bare-metal) approach is CGI. In CGI, a request for a
>> page runs a script, the output of which is the HTML page. I think this
>> only requires that the server has Python installed, which you have said
>> is the case. Python has signifigant standard library support for writing
>> CGI.[/color]
>
> Thanks, that makes much more sense to me now. But does this mean I can
> still write HTML normally? What would an example be of having HTML
> within a Python script? I have a hard time picturing this, because I
> imagine that most of my pages will be almost all HTML, with just a bit
> of Python here and there, perhaps to insert headers and footers. Is all
> the HTML just wrapped in a big print statement, or something like that?[/color]

When writing for CGI, it will be.

It will basically look like this:

#!/bin/env python

# these are custom headers, Content-type is mandatory
print "Content-Type: text/html"
# an empty line separates headers from content
print

print "<html>..."
# do stuff here
print "...</html>"

Georg

[Cameron Laird]

Re: embedding python in HTML

In article <bpCdne1jK5jC1G jeRVn-gw@rcn.net>,
John Salerno <johnjsal@NOSPA Mgmail.com> wrote:[color=blue]
>bruno at modulix wrote:
>[color=green]
>> You've got to understand that Python is *not* a 'ServerPage' language
>> (-> php, asp, jsp etc) in itself. Your server can now run python, fine,
>> but *how* ? CGI ? FastCGI ? mod_python ? other ? (hint: it's probably
>> just plain old CGI...)[/color]
>
>So does that mean I need to have something further on the server? Or is
>this something I can do on my end? How do I find out what I need?[/color]

While others have provided salient technical details to
you, my recommendation is to start with your provider.
Say to him, "when you tell me you've 'turned Python on',
what exactly does that mean? Have you configured Web
service for CGI? Zope? ..." This is a case where it's
good to talk to a person.

[Steve Holden]

Re: embedding python in HTML

bruno at modulix wrote:[color=blue]
> John Salerno wrote:
>[color=green]
>>Rene Pijlman wrote:
>>
>>[color=darkred]
>>>John Salerno:
>>>[Python alternative for PHP]
>>>
>>>
>>>>So to do this with Python, do I simply integrate it into the HTML as
>>>>above, with no extra steps?
>>>
>>>
>>>You'd need something like the PHP engine, that understands Python rather
>>>than PHP.[/color]
>>
>>
>>My web server can run Python, fortunately. Now that they've turned it on
>>for me, I wanted to try it out, but I didn't know how to go about
>>writing a bit of code to stick into an HTML file.[/color]
>
>
> You've got to understand that Python is *not* a 'ServerPage' language
> (-> php, asp, jsp etc) in itself. Your server can now run python, fine,
> but *how* ? CGI ? FastCGI ? mod_python ? other ? (hint: it's probably
> just plain old CGI...)
>
>[/color]
It's not an Active Scripting language by default after installation of
the win32all extensions, but it can be made one, giving it access to
Request, Response and the other usual suspects in the ASP environment.

This wouldn't be my preferred way to use it, but (for example) it allows
you to include Python sources in VBScript pages and have your VBScript
code call Python functions and procedures. This alone is sometimes
worthwhile.

regards
Steve
--
Steve Holden +44 150 684 7255 +1 800 494 3119
Holden Web LLC www.holdenweb.com
PyCon TX 2006 www.python.org/pycon/

[Christoph Zwerschke]

Re: embedding python in HTML

Rene Pijlman wrote:[color=blue]
> There's also PSP:
> http://www.ciobriefings.com/psp/[/color]

Another incarnation of PSP can be used as part of Webware for Python
(http://www.w4py.org).

And one of the more modern solutions that should be mentioned is Kid
(http://kid.lesscode.org).

-- Christoph

[Magnus Lycka]

Re: embedding python in HTML

John Salerno wrote:[color=blue]
> Thanks, that makes much more sense to me now. But does this mean I can
> still write HTML normally? What would an example be of having HTML
> within a Python script? I have a hard time picturing this, because I
> imagine that most of my pages will be almost all HTML, with just a bit
> of Python here and there, perhaps to insert headers and footers. Is all
> the HTML just wrapped in a big print statement, or something like that?[/color]

Imagine for instance, that you have an HTML file where you
want to print a current timestamp when the page is displayed.

A simple way to do this would be to just give your HTML file
another extension (e.g. .tmpl, short for template). Keep the
file as it is, just put the text

%(timestamp)s

in the place(s) where you want your timestamp to appear
in the HTML file.

In your CGI script you can then do something like this:

#!/usr/bin/python -u
import time
print "Content-type: text/html\n"
text = open('myfile.tm pl).read()
print text % ('timestamp':ti me.asctime())

The inital Content-type line is important, and it must be
followed by a blank line before the actual content.

Look at the cgitb module too.

Instead of the common Python % interpolation, you could use
string.Template (with a current Python) or one of the many
templating systems around. Since your needs are likely to
grow, you might also want to have a look at one of the many
tool kits for Python and the web. Right now, it seems that
django and turbogears are the most popular. Cherrypy and
web.py are somewhat smaller and simpler systems. Unless you
use one of these tool kits, your homegrown code might turn
into yet another web tool kit eventually, and we have enough
of them already... (Too many I'd say...)

You should also note that traditional CGI scripts are rather
slow with Python, since Python's startup time is significant.
A system where the Python interpreter is already running, as
mod_python embedded in Apache is faster. But by all means, try
it as CGI. It might well be enough for your needs. It's been
ok for me.