Downloading/exporting a csv file when clicked on a button in web.py python

问题

I am using python web.py framework to build a small web app.

It consists of a

Home page that takes a url as input
Reads anchor text and anchor tags from it
Writes it to csv file and downloads it

Here the steps 2 and 3 happens when we clicked on a export the links button, below is my code

code.py

import web
from web import form
import urlparse
from urlparse import urlparse as ue
import urllib2
from BeautifulSoup import BeautifulSoup
import csv
from cStringIO import StringIO

urls = (
    '/', 'index',
    '/export', 'export',
)

app =  web.application(urls, globals())
render = web.template.render('templates/')

class index:
    def GET(self):
        return render.home()


class export:

    def GET(self):
        i = web.input()
        if i.has_key('url') and i['url'] !='':
            url = i['url'] 
            page = urllib2.urlopen(url)
            html = page.read()
            page.close()


            decoded = ue(url).hostname
            if decoded.startswith('www.'):
                decoded = ".".join(decoded.split('.')[1:])
            file_name = str(decoded.split('.')[0])

            csv_file = StringIO()
            csv_writer = csv.writer(csv_file)
            csv_writer.writerow(['Name', 'Link'])

            soup = BeautifulSoup(html)
            for anchor_tag in soup.findAll('a', href=True):     
                csv_writer.writerow([anchor_tag.text,anchor_tag['href']]) 
            web.header('Content-Type','text/csv')       
            web.header('Content-disposition', 'attachment; filename=%s.csv'%file_name)
            return csv_file.getvalue()

if __name__ == "__main__":
    app.run()

home.html:

$def with()
<html>
 <head>
   <title>Home Page</title>
 </head>
 <body>
     <form method="GET" action='/export'>
        <input type="text" name="url" maxlength="500" />
        <input class="button" type="submit" name="export the links" value="export the links" />
      </form>
 </body>
</html>

The above html code displays a form with a text box that takes a url , and has button export the links button that downloads/exports the csv file with the anchor tag links and text.

For example when we submit http://www.google.co.in and click export the links, all the anchor urls and anchor text are saving in to csv file and downloading successfully
but for example when we given the other url like http://stackoveflow.com immediately and click export the links button, the csv file (created with domain name of the url as shown in the above code) is downloading with tag links , but the downloaded csv file also contains the data(anchor text and links) of the previous url that is http://www.google.co.in.

That is the data is overrriding in the same csv file from different urls, can anyone please let me know whats wrong in the above code(export class) that generates the csv file, why the data is overwriting instead of creating a new csv file with the different name created dynamically ?

Finally my intention is to download/export a new csv file with domain name(sliced as above in my code) of the url by writing data (anchor tag text and url ) from the url in to it each time when we give the new url.

Can anyone please extend/make necessary changes to my above code to download an individul csv file for individual url .........

来源：https://stackoverflow.com/questions/15019549/downloading-exporting-a-csv-file-when-clicked-on-a-button-in-web-py-python

标签

python

button

csv

export

web.py