perl WWW::Mechanize can't seem to find the right form or assign fields or click submit - forms

Question

So I'm trying to create a perl script that logs in to SAP BusinessObjects Central Management Console (CMC) page but it doesn't even look like it's finding the right form or finding the right field or even clicking Submit.
Here's my code:
use strict;
use warnings;
use WWW::Mechanize;
use HTTP::Cookies;
my $mech = WWW::Mechanize->new();
$mech->cookie_jar(HTTP::Cookies->new());
$mech->get("http://myserver:8080/BOE/CMC");
$mech->form_name("_id2");
$mech->field("_id2:logon:CMS", "MYSERVER:6400");
$mech->field("_id2:logon:SAP_SYSTEM", "");
$mech->field("_id2:logon:SAP_CLIENT", "");
$mech->field("_id2:logon:USERNAME", "MYUSER");
$mech->field("_id2:logon:PASSWORD", "MYPWD");
$mech->field("_id2:logon:AUTH_TYPE", "secEnterprise");
$mech->click;
print $mech->content();
When I run it, I don't get any errors but the output I get is the login page again. Even more puzzling, it doesn't seem to be accepting the field values I send it (the output would display default values instead of the values I assign it). Putting in a wrong user or password doesn't change anything - no error but I just get the login page back with default values
I think the script itself is fine since I changed the necessary fields and I was able to log in to our Nagios page (the output page definitely shows Nagios details). I think the CMC page is not so simple, but I need help in figuring out how to make it work.
What I've tried:
1
use Data::Dumper;
print $mech->forms;
print Dumper($mech->forms());
What that gave me is:
Current form is: WWW::Mechanize=HASH(0x243d828)
Part of the Dumper output is:
'attr' => {
'target' => 'servletBridgeIframe',
'style' => 'display:none;',
'method' => 'post'
},
'inputs' => []
I'm showing just that part of the Dumper output because it seems that's the relevant part. When I tried the same thing with our Nagios page, the 'attr' section had a 'name' field which the above doesn't. The Nagios page also had entries for 'inputs' such as 'useralias' and 'password' but the above doesn't have any entries.
2
$mech->form_number(1);
Since I wasn't sure I was referencing the form correctly, I just had it try using the first form it finds (the page only has one form anyway). My result was the same - no error and the output is the login page with default values.
3
I messed around with escaping (with '\') the underscore (_) and colon (:) in the field names.
I've searched and didn't find anything that said I had to escape any characters but it was worth a shot. All I know is, the Nagios page field names only contained letters and it worked.
I got field names from Chrome's developer tool. For example, the User Name form field showed:
<input type="text" id="_id2:logon:USERNAME" name="_id2:logon:USERNAME" value="Administrator">
I don't know if Mechanize has a problem with names starting with underscore or names containing colons.
4
$mech->click("_id2:logon:logonButton");
Since I wasn't sure the "Log On" button was being clicked I tried to specify it but it gave me an error:
No clickable input with name _id2:logon:logonButton at /usr/share/perl5/WWW/Mechanize.pm line 1676
That's probably because there is no name defined on the button (I used the id instead) but I thought it was worth a shot. Here's the code of the button:
<input type="submit" id="_id2:logon:logonButton" value="Log On" class="logonButtonNoHover logon_button_no_hover" onmouseover="this.className = 'logonButtonHover logon_button_hover';" onmouseout="this.className = 'logonButtonNoHover logon_button_no_hover';">
There's only one button on the form anyway so I shouldn't have needed to specify it (I didn't need to for the Nagios page)
5
The interactive shell of Mechanize
Here's the output when I tried to retrieve all forms on the page:
$ perl -MWWW::Mechanize::Shell -eshell
(no url)>get http://myserver:8080/BOE/CMC
Retrieving http://myserver:8080/BOE/CMC(200)
http://myserver:8080/BOE/CMC>forms
Form [1]
POST http://myserver:8080/BOE/CMC/1412201223/admin/logon.faces
Help!
I don't really know perl so I don't know how to troubleshoot this further - especially since I'm not seeing errors. If someone can direct me to other things to try, it would be helpful.

Answer 1

In this age of DOM and Javascript, there's lots of things that can go wrong with Web automation. From your results, it looks like maybe the form is built in browser space, which can be really hard to deal with programmatically.
The way to be sure is to dump the original response and look at the form code it contains.
If that turns out to be your problem, your simplest recourse is something like Mozilla::Mechanize.

Answer 2

When dealing with forms, it can sometimes be easier to replicate the request the form generates than to try to work with the form through Mechanize.
Try using your browser's developer tools to monitor what happens when you log into the site manually (in Firefox or Chrome it'll be under the Network tab), and then generate the same request with Mechanize.
For example, the resulting code MIGHT look something like:
my $post_data => {
'_id2:logon:CMS' => "MYSERVER:6400",
'_id2:logon:SAP_SYSTEM' => "",
'_id2:logon:SAP_CLIENT' => "",
'_id2:logon:USERNAME' => "MYUSER",
'_id2:logon:PASSWORD' => "MYPWD",
'_id2:logon:AUTH_TYPE' => "secEnterprise",
};
$mech->post($url, $post_data);
unless ($mech->success()){
warn "Failed to post to $url: " . $mech->response()->status_line() . "\n";
}
print $mech->content();
Where %post_data should match exactly the data that's passed in the manual post to the site and not just what's in the HTML--the keys or data could be transformed by javascript before the actual post is made.

Answer 3

I had someone more knowledgeable than me give me help. The main hurdle was how the page was constructed in frames and how it operated. Here are the details:
The URL of the frame that contained the login page is "http://myserver:8080/BOE/CMC/0000000000/myuser/logon.faces". The main frame of the page had a form in it, but it wasn't the logon form, which explains why the form from my original code didn't have the logon fields I was expecting.
The other "gotcha" that I ran into was that after a successful logon, the site redirects you to a different URL: "http://myserver:8080/BOE/CMC/0000000000/myuser/App/home.faces?service=%2Fmyuser%2FApp%2F". So to check a successful login, I had to get this URL and check for whatever text I decided to look for.
I also had to refer to the logon form by id and not by name (since the form did not have a name).
Here's the working code:
use strict;
use warnings;
use WWW::Mechanize;
use HTTP::Cookies;
my $mech = WWW::Mechanize->new();
$mech->cookie_jar(HTTP::Cookies->new());
$mech->get("http://myserver:8080/BOE/CMC/0000000000/myuser/logon.faces");
$mech->form_id("_id2");
$mech->field("_id2:logon:CMS", "MYSERVER:6400");
$mech->field("_id2:logon:SAP_SYSTEM", "");
$mech->field("_id2:logon:SAP_CLIENT", "");
$mech->field("_id2:logon:USERNAME", "MyUser");
$mech->field("_id2:logon:PASSWORD", "MyPwd");
$mech->field("_id2:logon:AUTH_TYPE", "secEnterprise");
$mech->click;
$mech->get("http://myserver:8080/BOE/CMC/0000000000/myuser/App/home.faces?service=%2Fmyuser%2FApp%2FappService.jsp&appKind=CMC");
$output_page = $mech->content();
if (index($output_page, "Welcome:") != -1)
{
print "\n\n+++++ Successful login! ++++++\n\n";
}
else
{
print "\n\n----- Login failed!-----\n\n";
}
For validating that I had successfully logged in, I kept it very simple and just searched for the "Welcome:" text (as in "Welcome: MyUser").