No elements found for form number 2 in phantomjs - perl

Question

when I am using "--disk-cache=true" in phantomjs_arg then it's getting error In this line:
my $form = $self->{obj_mech}->form_number( 2 );
No elements found for form number 2 at modules/TestLogin.pm line 1129.
at /usr/local/share/perl/5.22.1/WWW/Mechanize/PhantomJS.pm line 796.
WWW::Mechanize::PhantomJS::signal_condition(WWW::Mechanize::PhantomJS=HASH(0x4cfa120),
"No elements found for form number 2") called at
/usr/local/share/perl/5.22.1/WWW/Mechanize/PhantomJS.pm line 1732
WWW::Mechanize::PhantomJS::xpath(WWW::Mechanize::PhantomJS=HASH(0x4cfa120),
"(//form)[2]", "user_info", "form number 2", "single", 1) called at
/usr/local/share/perl/5.22.1/WWW/Mechanize/PhantomJS.pm line 2102
WWW::Mechanize::PhantomJS::form_number(WWW::Mechanize::PhantomJS=HASH(0x4cfa120),
2) called at modules/TestLogin.pm line 1129
TestLogin::TestLogin_login(TestLogin=HASH(0x4f5c8a8)) called at collectBets.pl line 20 Debugged program terminated. Use q to quit
or R to restart, use o inhibit_exit to avoid stopping after program
termination, h q, h R or h o to get additional info.
without disk-cashe it's working fine.
This is my sample code for better understanding.
#!/usr/bin/perl
use strict;
use warnings;
use Helper;
use WWW::Mechanize::PhantomJS;
use DataBase;
use MyConfig;
use JSON;
use DateTime;
use HTML::Entities;
sub new($$) {
my ($class,$params) = #_;
my $self = $params || {};
bless $self, $class;
$self->{obj_mech} = WWW::Mechanize::PhantomJS -> new( phantomjs_arg => ['--ssl-protocol=any','--disk-cache=true','--max-disk-cache-size=1024'], ignore_ssl_errors => 1);
$self->{obj_helper} = new Helper();
#$self->{obj_db} = new DataBase();
$self->{logged_in} = 0;
#$self->setTorProxy();
#$self->init_market_master();
return $self;
}
Login();
print "\nlogin done...\n";
exit;
sub Login {
my ($self) = #_;
my $html = $self->{obj_mech}->get( "https://www.gmail.com/" );
sleep(25);
$html = $self->{obj_mech}->content;
$self->{obj_mech}->viewport_size({ width => 1366, height => 768 });
my $form = $self->{obj_mech}->form_number( 2 );
my $user_name = '*****';
my $password = '******';
$self->{obj_mech}->set_fields('InputEmail' =>$user_name);
$self->{obj_mech}->set_fields('InputPassword' =>$password);
$self->{obj_mech}->click({ xpath => '//button[#class="PrimaryButton"]' });
sleep(20);
my $test_html=$self->{obj_mech}->content;
$self->{obj_helper}->writeFileNew( "TestLoginPage.html" , $test_html );
my $png = $self->{obj_mech}->content_as_png();
$self->{obj_helper}->writeFileNew( "LoginPage.png" , $png );
return 1;
}

Answer 1

Well, before looking at the disk-cache arguments, I found that there are no such elements.
# There is only 1 form. If you want to keep this line,
# you need to change the form number to 1
my $form = $self->{obj_mech}->form_number( 2 );
# I didn't find input field named 'InputEmail'
# The actual field name is 'Email'
$self->{obj_mech}->set_fields('InputEmail' =>$user_name);
# You have to click 'Next' button firstly then the password
# input box is shown. And the field name should be 'Passwd'
$self->{obj_mech}->set_fields('InputPassword' =>$password);
# The xpath of 'Sign in' button is //input[#value="Sign in"]
$self->{obj_mech}->click({ xpath => '//button[#class="PrimaryButton"]' });
A simple working script either with disk cache or without disk cache:
#! /usr/bin/perl
use strict;
use warnings;
use WWW::Mechanize::PhantomJS;
use open ':std', ':encoding(UTF-8)';
#my $p = WWW::Mechanize::PhantomJS->new(phantomjs_arg=>['--ssl-protocol=any','--disk-cache=false','--max-disk-cache-size=1024'],ignore_ssl_errors=>1);
my $p = WWW::Mechanize::PhantomJS->new(phantomjs_arg=>['--ssl-protocol=any','--disk-cache=true','--max-disk-cache-size=1024'],ignore_ssl_errors=>1);
my $html = $p->get("https://www.gmail.com/");
sleep(5);
write_html('first-page.html', $p->content);
$p->viewport_size({width=>1366,height=>768});
my $form = $p->form_number(1);
my $user_name = '*****';
my $password = '*****';
$p->set_fields('Email'=>$user_name);
sleep(5);
$p->click({xpath=>'//input[#value="Next"]'});
sleep(5);
write_html('after-click-next.html', $p->content);
$p->set_fields('Passwd'=>$password);
sleep(5);
$p->click({xpath=>'//input[#value="Sign in"]'});
sleep(5);
write_html('after-login.html', $p->content);
sub write_html {
my ($file, $content) = #_;
open my $fh, '>', $file or die;
print $fh $content;
close $fh;
}