www::mechanize::shell(3psme)
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 meaningful 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. - title
- Display the current page title as found in the "<TITLE>" tag.
- headers
- Prints all "<H1>" through "<H5>" strings found in the content, indented
accordingly. With an argument, prints only those levels; e.g.,
"headers 145" prints H1,H4,H5 strings only. - 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 "" - links
- 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 changesThis 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 user password - If you know the authority and the realm in advance, you can presupply
the credentials, for example at the start of the script :
>auth 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 $self->agent->ct - source
- Execute a batch of commands from a file
- Syntax:
source FILENAME - versions
- Print the version numbers of important modules
- Syntax:
versions - timeout
- Set new timeout value for the agent. Effects all subsequent requests.
VALUE is in seconds. - Syntax:
timeout VALUE - ct
- prints the content type of the most current response.
- Syntax:
ct - referrer
- set the value of the Referer: header
- Syntax:
referer URL
referrer URL - referer
- Alias for referrer
- response
- display the last server response
- "$shell->munge_code( CODE )"
- Munges a coderef to become code fit for output independent of
WWW::Mechanize::Shell. - "shell"
- This subroutine is exported by default as a convenience method so that
the following oneliner invocation works:
perl -MWWW::Mechanize::Shell -eshell - You can pass constructor arguments to this routine as well. Any scripts given in @ARGV will be run. If @ARGV is empty, an interactive loop will be started.
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 re-enable 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!
- o 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. - o 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
- o Add XPath expressions (by moving "WWW::Mechanize" from HTML::Parser
- to XML::XMLlib or maybe easier, by tacking Class::XPath onto an
HTML tree) - o Add "head" as a command ?
- o 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) 2002,2008 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