Hrpicot - cant extract what i want from page

Hi im starting to use hrpicot and im having problems extracting
descriptions of various concert events from a page. Here is a sample of
the html

Concerts
POPULAR

Middle Field! Vol.4
Featuring electric-pop band The Stealth, Mac and Masaru, and others. Mar 28, 7pm, ¥2,500 (adv)/ ¥3,000 (door). Shibuya O-Nest. Tel: 03-3498-9999.

Philip Woo featuring Brenda Vaughn
Japanese pianist and soul singer performing with Andy Wulf and Kaori Kobayashi. Mar 28 & 29, 7 & 9:30pm, ¥3,150. Cotton Club, Marunouchi. Tel: 03-3215-1555.
... ... ... etc

I can get the artist band names fine using
names = doc.search("//span[@class=‘textbold’]")

but i cant get teh descriptions. In fact the descriptions aren’t
indvidually wrapped up in any tags but rather just clumped together
under the paragraph tab with line breaks

So I thought id just try
descriptions =
doc.search("/html/body/div/table/tbody/tr[4]/td/table/tbody/tr/td[2]/table/tbody/tr/td/span/p")
but when i try to puts descriptions nothing is printed to the screen.

How would i go about getting this info??? any tips or ideas?

Thanks

more info…

the original website can be found at
http://metropolis.co.jp/tokyo/recent/listings.asp

i used firebug to retrieve the xpath address of the desired paragraph
(excerpted above). When I put it in doc.search it doesnt retrieve
anything, nothing at all???

Does anyone know why i cant??? Im banging my head against the wall

On Fri, Mar 28, 2008 at 2:11 AM, Adam A. [email protected]
wrote:


Kobayashi. Mar 28 & 29, 7 & 9:30pm, ¥3,150. Cotton Club, Marunouchi. but i cant get teh descriptions. In fact the descriptions aren't Thanks

Wow! It looks nice, but the html is really ugly. This would be
pretty hard to scrape on a regular basis. For artists, there are a
mix of tags, tags,
and I noticed one artist with no surrounding tags at all (Ex-press
Ver.2).

It can be really hard to work with inconsistent html, but I suppose it
could be done to some degree of accuracy. Any hpricot masters out
there? I’m sure you’d have to attack with regexps as well. Maybe
turning into text and then parsing is a better idea after all.

Todd

thanks tod for the reply. Yes even I thought that it was badly designed
and I dont have any web desing experience at all. In fact i learn the
basics of html, xml and xpath just for this.

Although those inconsitencies will prove to be a problem in the future
the one im having right now is getting any information at all. Surely
when i pass the xpath address for the paragraph element which contains
all the artists names and event descriptinos it should return something
rather than nothing. Is that right??? Every time a try to print to
screen the result of the search it just comes blank. Does anyone know
why???

Firebug puts in tbody’s into xpath’s that reach into tables even if the

tag is not in the html source. Try removing the tbody path and debug using shorter xpaths to initially address content further up in the hierarchy.

You might have some success addressing text nodes combined with some
subsequent regexp processing:

b = doc.search("//text()")

I think you might be more successful using a css selector instead of an
xpath selector. To overcome hpricot not supporting all xpath axes you
can sometimes find a way to address the elements with a clever css
selector.

It can be a challenge to use hpricot with malformed html or if there are
no containers wrapping items that otherwise appear visually as a list or
table. I haven’t tried it yet, but running the html through something
like tidy before parsing so might create some of the missing structure.

ok i have tried taking out the tbody tags completely and got some of the
text back. Ill experiment to see if i can get all of it.

Re: Tidy

I installed the gem and i got the example code

require ‘tidy’
Tidy.path = ‘/usr/lib/libtidy.so’
html = ‘titleBody’
xml = Tidy.open(:show_warnings=>true) do |tidy|
tidy.options.output_xml = true
puts tidy.options.show_warnings
xml = tidy.clean(html)
puts tidy.errors
puts tidy.diagnostics
xml
end
puts xml

now i have to change the path to whereever the lib is…well i foudn
tidys folder in my lib directory and changed the above to this

Tidy.path = ‘C:\ruby\lib\ruby\gems\1.8\gems\tidy-1.1.2\lib\tidy\tidylib’

and its complaining saying no such file… i tried

Tidy.path =
‘C:\ruby\lib\ruby\gems\1.8\gems\tidy-1.1.2\lib\tidy\tidylib.rb’

as thats the proper extension of the tidylib file but again it wont
work.

I cant find any tidylib file with an extenision .so

banging my head even more now :wink:

just downloaded a dll which i needed. Why doesnt that come with the
******* gem.

On Fri, Mar 28, 2008 at 11:42 AM, Dan D. [email protected]
wrote:

Firebug puts in tbody’s into xpath’s that reach into tables even if the tag is not in the html source. Try removing the tbody path and debug using shorter xpaths to initially address content further up in the hierarchy.

Yes, Firefox does it to make it more (X)HTML-conform. It took me a
while to get the hang of it. You might download the page using
open-uri and open it with your favourite editor, search the text and
work your way up through the tags.
Most sites don’t use , so just try it without it.

On Mar 28, 6:11 pm, Adam A. [email protected] wrote:


Tel: 03-3215-1555. indvidually wrapped up in any tags but rather just clumped together -- Posted viahttp://www.ruby-forum.com/.

Once you have the ‘name’ node you can use next_node to get the next
elements in the document
This method should work for your example:

def print_names_and_descriptions(hpricot_doc)
names = hpricot_doc.search(“//span[@class=‘textbold’]”)

names.each do |name|
node = name.next_node
node = node.next_node until node.text? and node.inner_text =~ /\w
+/

puts name.inner_text
puts node.to_s.strip
puts

end
end