hrpicot - cant extract what i want from page

A

Adam Akhtar

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


<p>
<a name="concerts"/>
<span class="heading">Concerts</span>
<br/>
<span class="subheading">POPULAR</span>
<br/>
<br/>
<span class="textbold">Middle Field! Vol.4</span >
<br/>
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.
<br/>
<br/>
<span class="textbold">Philip Woo featuring Brenda Vaughn</span>
<br/>
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.
<br/>
...
...
...
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 <br/>

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
 
A

Adam Akhtar

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
 
T

Todd Benson

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


<p>
<a name=3D"concerts"/>
<span class=3D"heading">Concerts</span>
<br/>
<span class=3D"subheading">POPULAR</span>
<br/>
<br/>
<span class=3D"textbold">Middle Field! Vol.4</span >
<br/>
Featuring electric-pop band The Stealth, Mac and Masaru, and others. Mar
28, 7pm, =A52,500 (adv)/ =A53,000 (door). Shibuya O-Nest. Tel: 03-3498-9= 999.
<br/>
<br/>
<span class=3D"textbold">Philip Woo featuring Brenda Vaughn</span>
<br/>
Japanese pianist and soul singer performing with Andy Wulf and Kaori
Kobayashi. Mar 28 & 29, 7 & 9:30pm, =A53,150. Cotton Club, Marunouchi.
Tel: 03-3215-1555.
<br/>
...
...
...
etc

I can get the artist band names fine using
names =3D doc.search("//span[@class=3D'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 <br/>

So I thought id just try
descriptions =3D
doc.search("/html/body/div/table/tbody/tr[4]/td/table/tbody/tr/td[2]/tab= le/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

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 <strong></strong> tags, <span class=3D"textbold"></span> 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
 
A

Adam Akhtar

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???
 
T

Thomas Wieczorek

Firebug puts in tbody's into xpath's that reach into tables even if the <tbody> 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 <tbody>, so just try it without it.
 
A

Adam Akhtar

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 = '<html><title>title</title>Body</html>'
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 ;-)
 
A

Adam Akhtar

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

daniel hoey

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

<p>
<a name="concerts"/>
<span class="heading">Concerts</span>
<br/>
<span class="subheading">POPULAR</span>
<br/>
<br/>
<span class="textbold">Middle Field! Vol.4</span >
<br/>
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.
<br/>
<br/>
<span class="textbold">Philip Woo featuring Brenda Vaughn</span>
<br/>
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.
<br/>
..
..
..
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 <br/>

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

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
 

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