I'm failing to get a node by its id.
The code is straight forward and should be self-explaining.
#!/usr/bin/perl
use Encode;
use utf8;
use LWP::UserAgent;
use URI::URL;
use Data::Dumper;
use HTML::TreeBuilder::XPath;
my $url = 'https://www.airbnb.com/rooms/1976460';
my $browser = LWP::UserAgent->new;
my $resp = $browser->get( $url, 'User-Agent' => 'Mozilla\/5.0' );
if ($resp->is_success) {
my $base = $resp->base || '';
print "-> base URL: $base\n";
my $data = $resp->decoded_content;
my $tree= HTML::TreeBuilder::XPath->new;
$tree->parse_content( $resp->decoded_content() );
binmode STDOUT, ":encoding(UTF-8)";
my $price_day = $tree->find('.//*[#id="price_amount"]/');
print Dumper($price_day);
$tree->delete();
}
The code above prints:
-> base URL: https://www.airbnb.com/rooms/1976460
$VAR1 = undef;
How can I select a node by its ID?
Thanks in advance.
Take that / off the end of that XPath.
.//*[#id="price_amount"]
should do. As it is, it's not valid XPath.
There is a trailing slash in your XPath, that you need to remove
my $price_day = $tree->find('.//*[#id="price_amount"]');
However, from my own testing, I believe that HTML::TreeBuilder::XPath is also having trouble parsing that specific URL. Perhaps because of the conditional comments?
As an alternative approach, I would recommend using Mojo::UserAgent and Mojo::DOM instead.
The following uses the css selector div#price_amount to easily find your desired element and print it out.
use strict;
use warnings;
use Mojo::UserAgent;
my $url = 'https://www.airbnb.com/rooms/1976460';
my $dom = Mojo::UserAgent->new->get($url)->res->dom;
my $price_day = $dom->at(q{div#price_amount})->all_text;
print $price_day, "\n";
Outputs:
$285
Note, there is a helpful 8 minute introductory video to this set of modules at Mojocast Episode 5.
Related
Here's the code:
$vizFile ='https://docs.recipeinvesting.com/t.aaaf.html';
my $ua = LWP::UserAgent->new;
$ua->timeout(10);
$ua->env_proxy;
my $response = $ua->get($vizFile);
if ($response->is_success) {print $response->decoded_content;}
else {print"\nError= $response->status_line]n";}
I get the message:
Error= HTTP::Response=HASH(0x3a9b810)->status_line]n
The url works fine if I put it in a browser.
This was working consistently (with plain http, using LWP::Simple), until the site made some changes.
Could it be the https that's making the difference?
Is there some way to get a less cryptic error message?
You can't put code in string literals and expect it to get executed. Sure, you can place variables for interpolation, but the making method calls falls on the other side of what's supported.
Replace
print"\nError= $response->status_line]n";
with
print "\nError= " . $response->status_line . "\n";
or
use feature qw( say );
say "\nError= " . $response->status_line;
This will print the status line as desired.
Please see following demo code, it is encouraged to include use strict; and use warnings; in the code what would assist you to avoid many potential problems
use strict;
use warnings;
use feature 'say';
use LWP::UserAgent;
my $url ='https://docs.recipeinvesting.com/t.aaaf.html';
my $ua = LWP::UserAgent->new;
$ua->timeout(10);
$ua->env_proxy;
my $response = $ua->get($url);
if( $response->is_success ){
say $response->decoded_content;
} else {
die $response->status_line;
}
Documentation: LWP::UserAgent
I have a doubt I've been trying to solve myself using CPAN modules documentation, but I'm a bit new and I'm confused with some terminology and sections within the different modules.
I'm trying to create the object in the code below, and get the absolute URL for relative links extracted from a website.
#!/usr/bin/perl
use strict;
use warnings;
use LWP::UserAgent;
use Digest::MD5 qw(md5_hex);
use URI;
my $url = $ARGV[0];
if ($url !~ m{^https?://[^\W]+-?\.com/?}i) {
exit(0);
}
my $ua = LWP::UserAgent->new;
$ua->timeout( 10 );
my $response = $ua->get( $url );
my $content = $response->decoded_content();
my $links = URI->new($content);
my $abs = $links->abs('http:', $content);
my $abs_links = $links->abs($abs);
while ($content =~ m{<a[^>]\s*href\s*=\s*"?([^"\s>]+)}gis) {
$abs_links = $1;
print "$abs_links\n";
print "Digest for the above URL is " . md5_hex($abs_links) . "\n";
}
The problem is when I try to add that part outside the While loop (the 3-line block preceding the loop), it does not work, whereas if I add the same part in the While loop, it will work fine. This one just gets the relative URLs from a given website, but instead of printing "Http://..." it prints "//...".
The script that works fine for me is the following:
#!/usr/bin/perl
use strict;
use warnings;
use LWP::UserAgent;
use Digest::MD5 qw(md5_hex);
use URI::URL;
my $url = $ARGV[0]; ## Url passed in command
if ($url !~ m{^https?://[\w]+-?[\w]+\.com/?}i) {
exit(0); ## Program stops if not valid URL
}
my $ua = LWP::UserAgent->new;
$ua->timeout( 10 );
my $response = $ua->get( $url ); ## Get response, not content
my $content = $response->decoded_content(); ## Now let's get the content
while ($content =~ m{<a[^>]\s*href\s*=\s*"?([^"\s>]+)}gis) { ## All links
my $links = $1;
my $abs = new URI::URL "$links";
my $abs_url = $abs->abs('http:', $links);
print "$abs_url\n";
print "Digest for the above URL is " . md5_hex($abs_url) . "\n";
}
Any ideas? Much appreciated.
I don't understand your code. There are a few weird bits:
[^\W] is the same as \w
The regex allows an optional - before and an optional / after .com, i.e. http://bitwise.complement.biz matches but http://cool-beans.com doesn't.
URI->new($content) makes no sense: $content is random HTML, not a URI.
$links->abs('http:', $content) makes no sense: $content is simply ignored, and $links->abs('http:') tries to make $links an absolute URL relative to 'http:', but 'http:' is not a valid URL.
Here's what I think you're trying to do:
#!/usr/bin/perl
use strict;
use warnings;
use LWP::UserAgent;
use HTML::LinkExtor;
use Digest::MD5 qw(md5_hex);
#ARGV == 1 or die "Usage: $0 URL\n";
my $url = $ARGV[0];
my $ua = LWP::UserAgent->new(timeout => 10);
my $response = $ua->get($url);
$response->is_success or die "$0: " . $response->request->uri . ": " . $response->status_line . "\n";
my $content = $response->decoded_content;
my $base = $response->base;
my #links;
my $p = HTML::LinkExtor->new(
sub {
my ($tag, %attrs) = #_;
if ($tag eq 'a' && $attrs{href}) {
push #links, "$attrs{href}"; # stringify
}
},
$base,
);
$p->parse($content);
$p->eof;
for my $link (#links) {
print "$link\n";
print "Digest for the above URL is " . md5_hex($link) . "\n";
}
I don't try to validate the URL passed in $ARGV[0]. Leave it to LWP::UserAgent. (If you don't like this, just add the check back in.)
I make sure $ua->get($url) was successful before proceeding.
I get the base URL for absolutifying relative links from $response->base.
I use HTML::LinkExtor for parsing the content, extracting links, and making them absolute.
I think your biggest mistake is trying to parse links out of HTML using a regular expression. You would be far better advised to use a CPAN module for this. I'd recommend WWW::Mechanize, which would make your code look something like this:
#!/usr/bin/perl
use strict;
use warnings;
use feature 'say';
use WWW::Mechanize;
use Digest::MD5 qw(md5_hex);
use URI;
my $url = $ARGV[0];
if ($url !~ m{^https?://[^\W]+-?\.com/?}i) {
exit(0);
}
my $ua = WWW::Mechanize->new;
$ua->timeout( 10 );
$ua->get( $url );
foreach ($ua->links) {
say $_->url;
say "Digest for the above URL is " . md5_hex($_->url) . "\n";
}
That looks a lot simpler to me.
I've created a perl script to use HTML::TableExtract to scrape data from tables on a site.
It works great to dump out table data for unsecured sites (i.e. HTTP site), but when I try HTTPS sites, it doesn't work (the tables_report line just prints blank.. it should print a bunch of table data).
However, if I take the content of that HTTPS page, and save it to an html file and then post it on an unsecured HTTP site (and change my content to point to this HTTP page), this script works as expected.
Anyone know how I can get this to work over HTTPS?
#!/usr/bin/perl
use lib qw( ..);
use HTML::TableExtract;
use LWP::Simple;
use Data::Dumper;
# DOESN'T work:
my $content = get("https://datatables.net/");
# DOES work:
# my $content = get("http://www.w3schools.com/html/html_tables.asp");
my $te = HTML::TableExtract->new();
$te->parse($content);
print $te->tables_report(show_content=>1);
print "\n";
print "End\n";
The sites mentioned above for $content are just examples.. these aren't really the sites I'm extracting, but they work just like the site I'm really trying to scrape.
One option I guess is for me to use perl to download the page locally first and extract from there, but I'd rather not, if there's an easier way to do this (anyone that helps, please don't spend any crazy amount of time coming up with a complicated solution!).
The problem is related to the user agent that LWP::Simple uses, which is stopped at that site. Use LWP::UserAgent and set an allowed user agent, like this:
use strict;
use warnings;
use LWP::UserAgent;
my $ua = LWP::UserAgent->new;
my $url = 'https://datatables.net/';
$ua->agent("Mozilla/5.0"); # set user agent
my $res = $ua->get($url); # send request
# check the outcome
if ($res->is_success) {
# ok -> I simply print the content in this example, you should parse it
print $res->decoded_content;
}
else {
# ko
print "Error: ", $res->status_line, "\n";
}
This is because datatables.net is blocking LWP::Simple requests. You can confirm this by using below code:
#!/usr/bin/perl
use strict;
use warnings;
use LWP::Simple;
print is_success(getprint("https://datatables.net/"));
Output:
$ perl test.pl
403 Forbidden <URL:https://datatables.net/>
You could try using LWP::RobotUA. Below code works fine for me.
#!/usr/bin/perl
use strict;
use warnings;
use LWP::RobotUA;
use HTML::TableExtract;
my $ua = LWP::RobotUA->new( 'bot_chankey/1.1', 'chankeypathak#stackoverflow.com' );
$ua->delay(5/60); # 5 second delay between requests
my $response = $ua->get('https://datatables.net/');
if ( $response->is_success ) {
my $te = HTML::TableExtract->new();
$te->parse($response->content);
print $te->tables_report(show_content=>1);
}
else {
die $response->status_line;
}
In the end, a combination of Miguel and Chankey's responses provided my solution. Miguel's made up most of my code, so I selected that as the answer, but here is my "final" code (got a lot more to do, but this is all I couldn't figure out.. the rest should be no problem).
I couldn't quite get either mentioned by Miguel/Chankey to work, but they got me 99% of the way.. then I just had to figure out how to get around the error "certificate verify failed". I found that answer with Miguel's method right away, so in the end, I mostly used his code, but both responses were great!
#!/usr/bin/perl
use lib qw( ..);
use strict;
use warnings;
use LWP::UserAgent;
use HTML::TableExtract;
use LWP::RobotUA;
use Data::Dumper;
my $ua = LWP::UserAgent->new(
ssl_opts => { SSL_verify_mode => 'SSL_VERIFY_PEER' },
);
my $url = 'https://WebsiteIUsedWasSomethingElse.com';
$ua->agent("Mozilla/5.0"); # set user agent
my $res = $ua->get($url); # send request
# check the outcome
if ($res->is_success)
{
my $te = HTML::TableExtract->new();
$te->parse($res->content);
print $te->tables_report(show_content=>1);
}
else {
# ko
print "Error: ", $res->status_line, "\n";
}
my $url = "https://ohsesfire01.summit.network/reports/slices";
my $user = 'xxxxxx';
my $pass = 'xxxxxx';
my $ua = new LWP::UserAgent;
my $request = new HTTP::Request GET=> $url;
# authenticate
$request->authorization_basic($user, $pass);
my $page = $ua->request($request);
I am running
#!/usr/bin/perl -w
use strict;
use LWP::Simple;
The variable $site has the html code.
Also you can use the function getstore to save the html data to a file, like:
my $http_code = getstore( 'http://www.google.com/', 'google.html' );
It would help you a lot if you could see the reason for the failure. I suggest you use the core LWP instead of the simple version. Like this:
#!/usr/bin/perl
use strict;
use warnings;
use LWP;
my $ua = LWP::UserAgent->new;
my $response = $ua->get('http://www.google.com/');
die 'Couldn't get it: ', $response->status_line unless $response->is_success;
my $site = $response->decoded_content;
print 'Got it.';
I'm using XML::RSSLite for parsing RSS data I retrieved using LWP. LWP is correctly retrieving in the right encoding but when using RSSLite to parse the data, the encoding seems to be lost and characteres like é, è, à, etc. are deleted from the output. Is there an option to set in order to force the encoding?
Here is my script:
use strict;
use XML::RSSLite;
use LWP::UserAgent;
use HTTP::Headers;
use utf8;
my $ua = LWP::UserAgent->new;
$ua->timeout(10);
$ua->env_proxy;
my $URL = "http://www.boursier.com/syndication/rss/news/FR0004031839/FR";
my $response = $ua->get($URL);
if ($response->is_success) {
my $content = $response->decoded_content((charset => 'UTF-8'));
my %result;
parseRSS(\%result, \$content);
foreach my $item (#{ $result{items} }) {
print "ITEM: $item->{title}\n";
}
}
I tried to use XML::RSS as it seems to have more option that may be handy in my case but it failed to install unfortunately. :(
I like that Mojo::UserAgent along with Mojo::DOM already have the support I need without me tracking down the right combinations of modules to use, and it handles the UTF-8 bits without me doing anything special:
use v5.10;
use open qw( :std :utf8 );
use Mojo::UserAgent;
my $ua = Mojo::UserAgent->new;
my $URL = "http://www.boursier.com/syndication/rss/news/FR0004031839/FR";
my $response = $ua->get($URL)->res;
my #links = $response
->dom( 'item > title' )
->map( sub { $_->text } )
->each;
$" = "\n";
print "#links\n";
I have another example at Painless RSS processing with Mojo
The RSSLite documentation explicitely states:
Remove characters other than 0-9~!##$%^&*()-+=a-zA-Z[];',.:"<>?\s
Therefore, the module is hopelessly broken. Try again with XML::Feed