file::fetch.3

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The name of the output file. This is the same as \f(CW$ff\fR\->file,
but any query parameters are stripped off. For example:
.Sp
.Vb 1
\&    http://example.com/index.html?x=y
.Ve
.Sp
would make the output file be \f(CW\*(C`index.html\*(C'\fR rather than 
\&\f(CW\*(C`index.html?x=y\*(C'\fR.
.SH "METHODS"
.IX Header "METHODS"
.ie n .Sh "$ff = File::Fetch\->new( uri => 'http://some.where.com/dir/file.txt' );"
.el .Sh "\f(CW$ff\fP = File::Fetch\->new( uri => 'http://some.where.com/dir/file.txt' );"
.IX Subsection "$ff = File::Fetch->new( uri => 'http://some.where.com/dir/file.txt' );"
Parses the uri and creates a corresponding File::Fetch::Item object,
that is ready to be \f(CW\*(C`fetch\*(C'\fRed and returns it.
.PP
Returns false on failure.
.ie n .Sh "$ff\->fetch( [to => /my/output/dir/] )"
.el .Sh "\f(CW$ff\fP\->fetch( [to => /my/output/dir/] )"
.IX Subsection "$ff->fetch( [to => /my/output/dir/] )"
Fetches the file you requested. By default it writes to \f(CW\*(C`cwd()\*(C'\fR,
but you can override that by specifying the \f(CW\*(C`to\*(C'\fR argument.
.PP
Returns the full path to the downloaded file on success, and false
on failure.
.ie n .Sh "$ff\->error([\s-1BOOL\s0])"
.el .Sh "\f(CW$ff\fP\->error([\s-1BOOL\s0])"
.IX Subsection "$ff->error([BOOL])"
Returns the last encountered error as string.
Pass it a true value to get the \f(CW\*(C`Carp::longmess()\*(C'\fR output instead.
.SH "HOW IT WORKS"
.IX Header "HOW IT WORKS"
File::Fetch is able to fetch a variety of uris, by using several
external programs and modules.
.PP
Below is a mapping of what utilities will be used in what order
for what schemes, if available:
.PP
.Vb 4
\&    file    => LWP, file
\&    http    => LWP, wget, curl, lynx
\&    ftp     => LWP, Net::FTP, wget, curl, ncftp, ftp
\&    rsync   => rsync
.Ve
.PP
If you'd like to disable the use of one or more of these utilities
and/or modules, see the \f(CW$BLACKLIST\fR variable further down.
.PP
If a utility or module isn't available, it will be marked in a cache
(see the \f(CW$METHOD_FAIL\fR variable further down), so it will not be
tried again. The \f(CW\*(C`fetch\*(C'\fR method will only fail when all options are
exhausted, and it was not able to retrieve the file.
.PP
A special note about fetching files from an ftp uri:
.PP
By default, all ftp connections are done in passive mode. To change
that, see the \f(CW$FTP_PASSIVE\fR variable further down.
.PP
Furthermore, ftp uris only support anonymous connections, so no
named user/password pair can be passed along.
.PP
\&\f(CW\*(C`/bin/ftp\*(C'\fR is blacklisted by default; see the \f(CW$BLACKLIST\fR variable
further down.
.SH "GLOBAL VARIABLES"
.IX Header "GLOBAL VARIABLES"
The behaviour of File::Fetch can be altered by changing the following
global variables:
.ie n .Sh "$File::Fetch::FROM_EMAIL"
.el .Sh "\f(CW$File::Fetch::FROM_EMAIL\fP"
.IX Subsection "$File::Fetch::FROM_EMAIL"
This is the email address that will be sent as your anonymous ftp
password.
.PP
Default is \f(CW\*(C`File\[e-mail]\*(C'\fR.
.ie n .Sh "$File::Fetch::USER_AGENT"
.el .Sh "\f(CW$File::Fetch::USER_AGENT\fP"
.IX Subsection "$File::Fetch::USER_AGENT"
This is the useragent as \f(CW\*(C`LWP\*(C'\fR will report it.
.PP
Default is \f(CW\*(C`File::Fetch/$VERSION\*(C'\fR.
.ie n .Sh "$File::Fetch::FTP_PASSIVE"
.el .Sh "\f(CW$File::Fetch::FTP_PASSIVE\fP"
.IX Subsection "$File::Fetch::FTP_PASSIVE"
This variable controls whether the environment variable \f(CW\*(C`FTP_PASSIVE\*(C'\fR
and any passive switches to commandline tools will be set to true.
.PP
Default value is 1.
.PP
Note: When \f(CW$FTP_PASSIVE\fR is true, \f(CW\*(C`ncftp\*(C'\fR will not be used to fetch
files, since passive mode can only be set interactively for this binary
.ie n .Sh "$File::Fetch::TIMEOUT"
.el .Sh "\f(CW$File::Fetch::TIMEOUT\fP"
.IX Subsection "$File::Fetch::TIMEOUT"
When set, controls the network timeout (counted in seconds).
.PP
Default value is 0.
.ie n .Sh "$File::Fetch::WARN"
.el .Sh "\f(CW$File::Fetch::WARN\fP"
.IX Subsection "$File::Fetch::WARN"
This variable controls whether errors encountered internally by
\&\f(CW\*(C`File::Fetch\*(C'\fR should be \f(CW\*(C`carp\*(C'\fR'd or not.
.PP
Set to false to silence warnings. Inspect the output of the \f(CW\*(C`error()\*(C'\fR
method manually to see what went wrong.
.PP
Defaults to \f(CW\*(C`true\*(C'\fR.
.ie n .Sh "$File::Fetch::DEBUG"
.el .Sh "\f(CW$File::Fetch::DEBUG\fP"
.IX Subsection "$File::Fetch::DEBUG"
This enables debugging output when calling commandline utilities to
fetch files.
This also enables \f(CW\*(C`Carp::longmess\*(C'\fR errors, instead of the regular
\&\f(CW\*(C`carp\*(C'\fR errors.
.PP
Good for tracking down why things don't work with your particular
setup.
.PP
Default is 0.
.ie n .Sh "$File::Fetch::BLACKLIST"
.el .Sh "\f(CW$File::Fetch::BLACKLIST\fP"
.IX Subsection "$File::Fetch::BLACKLIST"
This is an array ref holding blacklisted modules/utilities for fetching
files with.
.PP
To disallow the use of, for example, \f(CW\*(C`LWP\*(C'\fR and \f(CW\*(C`Net::FTP\*(C'\fR, you could
set \f(CW$File::Fetch::BLACKLIST\fR to:
.PP
.Vb 1
\&    $File::Fetch::BLACKLIST = [qw|lwp netftp|]
.Ve
.PP
The default blacklist is [qw|ftp|], as \f(CW\*(C`/bin/ftp\*(C'\fR is rather unreliable.
.PP
See the note on \f(CW\*(C`MAPPING\*(C'\fR below.
.ie n .Sh "$File::Fetch::METHOD_FAIL"
.el .Sh "\f(CW$File::Fetch::METHOD_FAIL\fP"
.IX Subsection "$File::Fetch::METHOD_FAIL"
This is a hashref registering what modules/utilities were known to fail
for fetching files (mostly because they weren't installed).
.PP
You can reset this cache by assigning an empty hashref to it, or
individually remove keys.
.PP
See the note on \f(CW\*(C`MAPPING\*(C'\fR below.
.SH "MAPPING"
.IX Header "MAPPING"
Here's a quick mapping for the utilities/modules, and their names for
the \f(CW$BLACKLIST\fR, \f(CW$METHOD_FAIL\fR and other internal functions.
.PP
.Vb 8
\&    LWP         => lwp
\&    Net::FTP    => netftp
\&    wget        => wget
\&    lynx        => lynx
\&    ncftp       => ncftp
\&    ftp         => ftp
\&    curl        => curl
\&    rsync       => rsync
.Ve
.SH "FREQUENTLY ASKED QUESTIONS"
.IX Header "FREQUENTLY ASKED QUESTIONS"
.Sh "So how do I use a proxy with File::Fetch?"
.IX Subsection "So how do I use a proxy with File::Fetch?"
\&\f(CW\*(C`File::Fetch\*(C'\fR currently only supports proxies with LWP::UserAgent.
You will need to set your environment variables accordingly. For
example, to use an ftp proxy:
.PP
.Vb 1
\&    $ENV{ftp_proxy} = \*(Aqfoo.com\*(Aq;
.Ve
.PP
Refer to the LWP::UserAgent manpage for more details.
.Sh "I used 'lynx' to fetch a file, but its contents is all wrong!"
.IX Subsection "I used 'lynx' to fetch a file, but its contents is all wrong!"
\&\f(CW\*(C`lynx\*(C'\fR can only fetch remote files by dumping its contents to \f(CW\*(C`STDOUT\*(C'\fR,
which we in turn capture. If that content is a 'custom' error file
(like, say, a \f(CW\*(C`404 handler\*(C'\fR), you will get that contents instead.
.PP
Sadly, \f(CW\*(C`lynx\*(C'\fR doesn't support any options to return a different exit
code on non\-\f(CW\*(C`200 OK\*(C'\fR status, giving us no way to tell the difference
between a 'successfull' fetch and a custom error page.
.PP
Therefor, we recommend to only use \f(CW\*(C`lynx\*(C'\fR as a last resort. This is 
why it is at the back of our list of methods to try as well.
.Sh "Files I'm trying to fetch have reserved characters or non-ASCII characters in them. What do I do?"
.IX Subsection "Files I'm trying to fetch have reserved characters or non-ASCII characters in them. What do I do?"
\&\f(CW\*(C`File::Fetch\*(C'\fR is relatively smart about things. When trying to write 
a file to disk, it removes the \f(CW\*(C`query parameters\*(C'\fR (see the 
\&\f(CW\*(C`output_file\*(C'\fR method for details) from the file name before creating
it. In most cases this suffices.
.PP
If you have any other characters you need to escape, please install 
the \f(CW\*(C`URI::Escape\*(C'\fR module from \s-1CPAN\s0, and pre-encode your \s-1URI\s0 before
passing it to \f(CW\*(C`File::Fetch\*(C'\fR. You can read about the details of URIs 
and \s-1URI\s0 encoding here:
.PP
.Vb 1
\&  http://www.faqs.org/rfcs/rfc2396.html
.Ve
.SH "TODO"
.IX Header "TODO"
.ie n .IP "Implement $PREFER_BIN" 4
.el .IP "Implement \f(CW$PREFER_BIN\fR" 4
.IX Item "Implement $PREFER_BIN"
To indicate to rather use commandline tools than modules
.SH "BUG REPORTS"
.IX Header "BUG REPORTS"
Please report bugs or other issues to <bug\-file\[e-mail]<gt>.
.SH "AUTHOR"
.IX Header "AUTHOR"
This module by Jos Boumans <[e-mail]>.
.SH "COPYRIGHT"
.IX Header "COPYRIGHT"
This library is free software; you may redistribute and/or modify it 
under the same terms as Perl itself.