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WWW-Mechanize-Shell-0.33
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/ WWW::Mechanize::Shell

NAME

WWW::Mechanize::Shell - An interactive shell for WWW::Mechanize

SYNOPSIS

From the command line as

perl -MWWW::Mechanize::Shell -eshell

or alternatively as a custom shell program via :

#!/usr/bin/perl -w
use strict;
use WWW::Mechanize::Shell;

my $shell = WWW::Mechanize::Shell->new("shell");

if (@ARGV) {
  $shell->source_file( @ARGV );
} else {
  $shell->cmdloop;
};

DESCRIPTION

This module implements a www-like shell above WWW::Mechanize and also has the capability to output crude Perl code that recreates the recorded session. Its main use is as an interactive starting point for automating a session through WWW::Mechanize.

The cookie support is there, but no cookies are read from your existing browser sessions. See HTTP::Cookies on how to implement reading/writing your current browsers cookies.

WWW::Mechanize::Shell->new %ARGS

This is the constructor for a new shell instance. Some of the options can be passed to the constructor as parameters.

By default, a file .mechanizerc (respectively mechanizerc under Windows) in the users home directory is executed before the interactive shell loop is entered. This can be used to set some defaults. If you want to supply a different filename for the rcfile, the rcfile parameter can be passed to the constructor :

rcfile => '.myapprc',

$shell->release_agent

Since the shell stores a reference back to itself within the WWW::Mechanize instance, it is necessary to break this circular reference. This method does this.

$shell->source_file FILENAME

The source_file method executes the lines of FILENAME as if they were typed in.

$shell->source_file( $filename );

$shell->display_user_warning

All user warnings are routed through this routine so they can be rerouted / disabled easily.

$shell->print_paged LIST

Prints the text in LIST using $ENV{PAGER}. If $ENV{PAGER} is empty, prints directly to STDOUT. Most of this routine comes from the perldoc utility.

$shell->link_text LINK

Returns a meaningfull text from a WWW::Mechanize::Link object. This is (in order of precedence) :

$link->text
$link->name
$link->url

$shell->history

Returns the (relevant) shell history, that is, all commands that were not solely for the information of the user. The lines are returned as a list.

print join "\n", $shell->history;

$shell->script

Returns the shell history as a Perl program. The lines are returned as a list. The lines do not have a one-by-one correspondence to the lines in the history.

print join "\n", $shell->script;

$shell->status

status is called for status updates.

$shell->display FILENAME LINES

display is called to output listings, currently from the history and script commands. If the second parameter is defined, it is the name of the file to be written, otherwise the lines are displayed to the user.

COMMANDS

The shell implements various commands :

exit

Leaves the shell.

restart

Restart the shell.

This is mostly useful when you are modifying the shell itself. It dosen't work if you use the shell in oneliner mode with -e.

get

Download a specific URL.

This is used as the entry point in all sessions

Syntax:

get URL

save

Download a link into a file.

If more than one link matches the RE, all matching links are saved. The filename is taken from the last part of the URL. Alternatively, the number of a link may also be given.

Syntax:

save RE

content

Display the content for the current page.

Syntax: content [FILENAME]

If the FILENAME argument is provided, save the content to the file.

A trailing "\n" is added to the end of the content when using the shell, so this might not be ideally suited to save binary files without manual editing of the produced script.

ua

Get/set the current user agent

Syntax:

# fake Internet Explorer
ua "Mozilla/4.0 (compatible; MSIE 4.01; Windows 98)"

# fake QuickTime v5
ua "QuickTime (qtver=5.0.2;os=Windows NT 5.0Service Pack 2)"

# fake Mozilla/Gecko based
ua "Mozilla/5.001 (windows; U; NT4.0; en-us) Gecko/25250101"

# set empty user agent :
ua ""

Display all links on a page

The links numbers displayed can used by open to directly select a link to follow.

parse

Dump the output of HTML::TokeParser of the current content

forms

Display all forms on the current page.

form

Select the form named NAME

If NAME matches /^\d+$/, it is assumed to be the (1-based) index of the form to select. There is no way of selecting a numerically named form by its name.

dump

Dump the values of the current form

value

Set a form value

Syntax:

value NAME [VALUE]

tick

Set checkbox marks

Syntax:

tick NAME VALUE(s)

If no value is given, all boxes are checked.

untick

Remove checkbox marks

Syntax:

untick NAME VALUE(s)

If no value is given, all marks are removed.

submit

submits the form without clicking on any button

click

Clicks on the button named NAME.

No regular expression expansion is done on NAME.

Syntax:

click NAME

If you have a button that has no name (displayed as NONAME), use

click ""

to click on it.

open

<open> accepts one argument, which can be a regular expression or the number of a link on the page, starting at zero. These numbers are displayed by the links function. It goes directly to the page if a number is used or if the RE has one match. Otherwise, a list of links matching the regular expression is displayed.

The regular expression should start and end with "/".

Syntax:

open  [ RE | # ]

back

Go back one page in the browser page history.

reload

Repeat the last request, thus reloading the current page.

Note that also POST requests are blindly repeated, as this command is mostly intended to be used when testing server side code.

browse

Open the web browser with the current page

Displays the current page in the browser.

set

Set a shell option

Syntax:

set OPTION [value]

The command lists all valid options. Here is a short overview over the different options available :

autosync      - automatically synchronize the browser window
autorestart   - restart the shell when any required module changes
                This does not work with C<-e> oneliners.
watchfiles    - watch all required modules for changes
cookiefile    - the file where to store all cookies
dumprequests  - dump all requests to STDOUT
dumpresponses - dump the headers of the responses to STDOUT
verbose       - print commands to STDERR as they are run,
                when sourcing from a file

history

Display your current session history as the relevant commands.

Syntax:

history [FILENAME]

Commands that have no influence on the browser state are not added to the history. If a parameter is given to the history command, the history is saved to that file instead of displayed onscreen.

script

Display your current session history as a Perl script using WWW::Mechanize.

Syntax:

script [FILENAME]

If a parameter is given to the script command, the script is saved to that file instead of displayed on the console.

This command was formerly known as history.

comment

Adds a comment to the script and the history. The comment is prepended with a \n to increase readability.

fillout

Fill out the current form

Interactively asks the values hat have no preset value via the autofill command.

auth

Set basic authentication credentials.

Syntax:

auth [authority realm] user password

If you get back a 401, you can simply supply the matching user and password, as the authority and realm are already known :

>get http://www.example.com
Retrieving http://www.example.com(401)
http://www.example.com>auth corion secret
http://www.example.com>get http://www.example.com
Retrieving http://www.example.com(200)
http://www.example.com>

If you know the authority and the realm in advance, you can presupply the credentials, for example at the start of the script :

>auth www.example.com:80 secure_realm corion secret
>get http://www.example.com
Retrieving http://www.example.com(200)
http://www.example.com>

table

Display a table described by the columns COLUMNS.

Syntax:

table COLUMNS

Example:

table Product Price Description

If there is a table on the current page that has in its first row the three columns Product, Price and Description (not necessarily in that order), the script will display these columns of the whole table.

The HTML::TableExtract module is needed for this feature.

tables

Display a list of tables.

Syntax:

tables

This command will display the top row for every table on the current page. This is convenient if you want to find out what the exact spellings for each column are.

The command does not always work nice, for example if a site uses tables for layout, it will be harder to guess what tables are irrelevant and what tables are relevant.

HTML::TableExtract is needed for this feature.

cookies

Set the cookie file name

Syntax:

cookies FILENAME

autofill

Define an automatic value

Sets a form value to be filled automatically. The NAME parameter is the WWW::Mechanize::FormFiller::Value subclass you want to use. For session fields, Keep is a good candidate, for interactive stuff, Ask is a value implemented by the shell.

A field name starting and ending with a slash (/) is taken to be a regular expression and will be applied to all fields with their name matching the expression. A field with a matching name still takes precedence over the regular expression.

Syntax:

autofill NAME [PARAMETERS]

Examples:

autofill login Fixed corion
autofill password Ask
autofill selection Random red green orange
autofill session Keep
autofill "/date$/" Random::Date string "%m/%d/%Y"

eval

Evaluate Perl code and print the result

Syntax:

eval CODE

For the generated scripts, anything matching the regular expression /\$self->agent\b/ is automatically replaced by $agent in your eval code, to do the Right Thing.

Examples:

# Say hello
eval "Hello World"

# And take a look at the current content type
eval $self->agent->ct

source

Execute a batch of commands from a file

Syntax:

source FILENAME

versions

Print the version numbers of important modules

Syntax:

versions

timeout

Set new timeout value for the agent. Effects all subsequent requests. VALUE is in seconds.

Syntax:

timeout VALUE

ct

prints the content type of the most current response.

Syntax:

ct

referrer

set the value of the Referer: header

Syntax:

referer URL
referrer URL

referer

Alias for referrer

response

display the last server response

SAMPLE SESSIONS

Entering values

# Search for a term on Google
get http://www.google.com
value q "Corions Homepage"
click btnG
script
# (yes, this is a bad example of automating, as Google
#  already has a Perl API. But other sites don't)

Retrieving a table

get http://www.perlmonks.org
open "/Saints in/"
table User Experience Level
script
# now you have a program that gives you a csv file of
# that table.

Uploading a file

get http://aliens:xxxxx/
value f path/to/file
click "upload"

Batch download

# download prerelease versions of my modules
get http://www.corion.net/perl-dev
save /.tar.gz$/

REGULAR EXPRESSION SYNTAX

Some commands take regular expressions as parameters. A regular expression must be a single parameter matching ^/.*/([isxm]+)?$, so you have to use quotes around it if the expression contains spaces :

/link_foo/       # will match as (?-xims:link_foo)
"/link foo/"     # will match as (?-xims:link foo)

Slashes do not need to be escaped, as the shell knows that a RE starts and ends with a slash :

/link/foo/       # will match as (?-xims:link/foo)
"/link/ /foo/"   # will match as (?-xims:link/\s/foo)

The /i modifier works as expected. If you desire more power over the regular expressions, consider dropping to Perl or recommend me a good parser module for regular expressions.

DISPLAYING HTML

WWW::Mechanize::Shell now uses the module HTML::Display to display the HTML of the current page in your browser. Have a look at the documentation of HTML::Display how to make it use your browser of choice in the case it does not already guess it correctly.

FILLING FORMS VIA CUSTOM CODE

If you want to stay within the confines of the shell, but still want to fill out forms using custom Perl code, here is a recipe how to achieve this :

Code passed to the eval command gets evalutated in the WWW::Mechanize::Shell namespace. You can inject new subroutines there and these get picked up by the Callback class of WWW::Mechanize::FormFiller :

# Fill in the "date" field with the current date/time as string
eval sub &::custom_today { scalar localtime };
autofill date Callback WWW::Mechanize::Shell::custom_today
fillout

This method can also be used to retrieve data from shell scripts :

# Fill in the "date" field with the current date/time as string
# works only if there is a program "date"
eval sub &::custom_today { chomp `date` };
autofill date Callback WWW::Mechanize::Shell::custom_today
fillout

As the namespace is different between the shell and the generated script, make sure you always fully qualify your subroutine names, either in your own namespace or in the main namespace.

GENERATED SCRIPTS

The script command outputs a skeleton script that reproduces your actions as done in the current session. It pulls in WWW::Mechanize::FormFiller, which is possibly not needed. You should add some error and connection checking afterwards.

ADDING FIELDS TO HTML

If you are automating a JavaScript dependent site, you will encounter JavaScript like this :

<script>
  document.write( "<input type=submit name=submit>" );
</script>

HTML::Form will not know about this and will not have provided a submit button for you (understandably). If you want to create such a submit button from within your automation script, use the following code :

$agent->current_form->push_input( submit => { name => "submit", value =>"submit" } );

This also works for other dynamically generated input fields.

To fake an input field from within a shell session, use the eval command :

eval $self->agent->current_form->push_input(submit=>{name=>"submit",value=>"submit"});

And yes, the generated script should do the Right Thing for this eval as well.

LOCAL FILES

If you want to use the shell on a local file without setting up a http server to serve the file, you can use the file: URI scheme to load it into the "browser":

get file:local.html
forms

PROXY SUPPORT

Currently, the proxy support is realized via a call to the env_proxy method of the WWW::Mechanize object, which loads the proxies from the environment. There is no provision made to prevent using proxies (yet). The generated scripts also load their proxies from the environment.

ONLINE HELP

The online help feature is currently a bit broken in Term::Shell, but a fix is in the works. Until then, you can reenable the dynamic online help by patching Term::Shell :

Remove the three lines

  my $smry = exists $o->{handlers}{$h}{smry}
? $o->summary($h)
: "undocumented";

in sub run_help and replace them by

my $smry = $o->summary($h);

The shell works without this patch and the online help is still available through perldoc WWW::Mechanize::Shell

BUGS

Bug reports are very welcome - please use the RT interface at https://rt.cpan.org/NoAuth/Bugs.html?Dist=WWW-Mechanize-Shell or send a descriptive mail to bug-WWW-Mechanize-Shell@rt.cpan.org . Please try to include as much (relevant) information as possible - a test script that replicates the undesired behaviour is welcome every time!

  • The two parameter version of the auth command guesses the realm from the last received response. Currently a RE is used to extract the realm, but this fails with some servers resp. in some cases. Use the four parameter version of auth, or if not possible, code the extraction in Perl, either in the final script or through eval commands.

  • The shell currently detects when you want to follow a JavaScript link and tells you that this is not supported. It would be nicer if there was some callback mechanism to (automatically?) extract URLs from JavaScript-infected links.

TODO

  • Add XPath expressions (by moving WWW::Mechanize from HTML::Parser to XML::XMLlib or maybe easier, by tacking Class::XPath onto an HTML tree)

  • Add head as a command ?

  • Optionally silence the HTML::Parser / HTML::Forms warnings about invalid HTML.

EXPORT

The routine shell is exported into the importing namespace. This is mainly for convenience so you can use the following commandline invocation of the shell like with CPAN :

perl -MWWW::Mechanize::Shell -e"shell"

COPYRIGHT AND LICENSE

This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself.

Copyright (C) 2002,2003 Max Maischein

AUTHOR

Max Maischein, <corion@cpan.org>

Please contact me if you find bugs or otherwise improve the module. More tests are also very welcome !

SEE ALSO

WWW::Mechanize,WWW::Mechanize::FormFiller