better regular expression?

[Vivek]

Hi,

I am trying to construct a regular expression using the re module that
matches for
1. my hostname
2. absolute from the root URLs including just "/"
3. relative URLs.

Basically I want the attern to not match for URLs that are not on my
host.

The following statement satisfies numbers 1 and 2, but not 3:

line =
re.sub(r'(href= ")(http[s]?://'+hostname+'[/]?|/)([^"]*?)(")',r'\1\2\ 3'+sInfo+r'\4', line)

An improvement that also partially satisfies number 3 is

line =
re.sub(r'(href= ")(http[s]?://'+hostname+'[/]?|/|[^h][^t][^t][^p][^:][^/][^/])([^"]*?)(")',r'\1\2\ 3'+sInfo+r'\4', line)

This is not complete because if the relative url is less than seven
characters, than it will not match.

Any suggestions?

Thanx.

[Andy Gross]

Re: better regular expression?


Check out the 'urlparse' module, in the standard library, unless for
some reason you *have* to use regular expressions.

/arg

On Dec 6, 2004, at 7:46 PM, Vivek wrote:
[color=blue]
> Hi,
>
> I am trying to construct a regular expression using the re module that
> matches for
> 1. my hostname
> 2. absolute from the root URLs including just "/"
> 3. relative URLs.
>
> Basically I want the attern to not match for URLs that are not on my
> host.
>
> The following statement satisfies numbers 1 and 2, but not 3:
>
> line =
> re.sub(r'(href= ")(http[s]?://'+hostname+'[/]?
> |/)([^"]*?)(")',r'\1\2\ 3'+sInfo+r'\4', line)
>
> An improvement that also partially satisfies number 3 is
>
> line =
> re.sub(r'(href= ")(http[s]?://'+hostname+'[/]?|/
> |[^h][^t][^t][^p][^:][^/][^/])([^"]*?)(")',r'\1\2\ 3'+sInfo+r'\4', line)
>
> This is not complete because if the relative url is less than seven
> characters, than it will not match.
>
> Any suggestions?
>
> Thanx.
>
> --
> http://mail.python.org/mailman/listinfo/python-list[/color]

[Roy Smith]

Re: better regular expression?

"Vivek" <vivek.bhaskar@ gmail.com> wrote:
[color=blue]
> Hi,
>
> I am trying to construct a regular expression using the re module that
> matches for
> 1. my hostname
> 2. absolute from the root URLs including just "/"
> 3. relative URLs.[/color]

Is your goal to learn more about regexes, or to parse URLs? If the
latter, my suggestion would be to look at the urlparse module; the hard
work has already been done for you.