App::Cpan(3pm) Perl Programmers Reference Guide App::Cpan(3pm)
NAME
App::Cpan - easily interact with CPAN from the command line
SYNOPSIS
# with arguments and no switches, installs specified modules
cpan module_name [ module_name ... ]
# with switches, installs modules with extra behavior
cpan [-cfFimtTw] module_name [ module_name ... ]
# use local::lib
cpan -I module_name [ module_name ... ]
# one time mirror override for faster mirrors
cpan -p ...
# with just the dot, install from the distribution in the
# current directory
cpan .
# without arguments, starts CPAN.pm shell
cpan
# without arguments, but some switches
cpan [-ahpruvACDLOPX]
DESCRIPTION
This script provides a command interface (not a shell) to CPAN. At the
moment it uses CPAN.pm to do the work, but it is not a one-shot command
runner for CPAN.pm.
Options
-a Creates a CPAN.pm autobundle with CPAN::Shell->autobundle.
-A module [ module ... ]
Shows the primary maintainers for the specified modules.
-c module
Runs a `make clean` in the specified module's directories.
-C module [ module ... ]
Show the Changes files for the specified modules
-D module [ module ... ]
Show the module details. This prints one line for each out-of-date
module (meaning, modules locally installed but have newer versions
on CPAN). Each line has three columns: module name, local version,
and CPAN version.
-f Force the specified action, when it normally would have failed. Use
this to install a module even if its tests fail. When you use this
option, -i is not optional for installing a module when you need to
force it:
% cpan -f -i Module::Foo
-F Turn off CPAN.pm's attempts to lock anything. You should be careful
with this since you might end up with multiple scripts trying to
muck in the same directory. This isn't so much of a concern if
you're loading a special config with "-j", and that config sets up
its own work directories.
-g module [ module ... ]
Downloads to the current directory the latest distribution of the
module.
-G module [ module ... ]
UNIMPLEMENTED
Download to the current directory the latest distribution of the
modules, unpack each distribution, and create a git repository for
each distribution.
If you want this feature, check out Yanick Champoux's
"Git::CPAN::Patch" distribution.
-h Print a help message and exit. When you specify "-h", it ignores
all of the other options and arguments.
-i module [ module ... ]
Install the specified modules. With no other switches, this switch
is implied.
-I Load "local::lib" (think like "-I" for loading lib paths). Too bad
"-l" was already taken.
-j Config.pm
Load the file that has the CPAN configuration data. This should
have the same format as the standard CPAN/Config.pm file, which
defines $CPAN::Config as an anonymous hash.
If the file does not exist, "cpan" dies.
-J Dump the configuration in the same format that CPAN.pm uses. This
is useful for checking the configuration as well as using the dump
as a starting point for a new, custom configuration.
-l List all installed modules with their versions
-L author [ author ... ]
List the modules by the specified authors.
-m Make the specified modules.
-M mirror1,mirror2,...
A comma-separated list of mirrors to use for just this run. The
"-P" option can find them for you automatically.
-n Do a dry run, but don't actually install anything. (unimplemented)
-O Show the out-of-date modules.
-p Ping the configured mirrors and print a report
-P Find the best mirrors you could be using and use them for the
current session.
-r Recompiles dynamically loaded modules with CPAN::Shell->recompile.
-s Drop in the CPAN.pm shell. This command does this automatically if
you don't specify any arguments.
-t module [ module ... ]
Run a `make test` on the specified modules.
-T Do not test modules. Simply install them.
-u Upgrade all installed modules. Blindly doing this can really break
things, so keep a backup.
-v Print the script version and CPAN.pm version then exit.
-V Print detailed information about the cpan client.
-w UNIMPLEMENTED
Turn on cpan warnings. This checks various things, like directory
permissions, and tells you about problems you might have.
-x module [ module ... ]
Find close matches to the named modules that you think you might
have mistyped. This requires the optional installation of
Text::Levenshtein or Text::Levenshtein::Damerau.
-X Dump all the namespaces to standard output.
Examples
# print a help message
cpan -h
# print the version numbers
cpan -v
# create an autobundle
cpan -a
# recompile modules
cpan -r
# upgrade all installed modules
cpan -u
# install modules ( sole -i is optional )
cpan -i Netscape::Booksmarks Business::ISBN
# force install modules ( must use -i )
cpan -fi CGI::Minimal URI
# install modules but without testing them
cpan -Ti CGI::Minimal URI
Environment variables
There are several components in CPAN.pm that use environment variables.
The build tools, ExtUtils::MakeMaker and Module::Build use some, while
others matter to the levels above them. Some of these are specified by
the Perl Toolchain Gang:
Lancaster Consensus:
<https://github.com/Perl-Toolchain-Gang/toolchain-site/blob/master/lancaster-consensus.md>
Oslo Consensus:
<https://github.com/Perl-Toolchain-Gang/toolchain-site/blob/master/oslo-consensus.md>
NONINTERACTIVE_TESTING
Assume no one is paying attention and skips prompts for
distributions that do that correctly. cpan(1) sets this to 1 unless
it already has a value (even if that value is false).
PERL_MM_USE_DEFAULT
Use the default answer for a prompted questions. cpan(1) sets this
to 1 unless it already has a value (even if that value is false).
CPAN_OPTS
As with "PERL5OPT", a string of additional cpan(1) options to add
to those you specify on the command line.
CPANSCRIPT_LOGLEVEL
The log level to use, with either the embedded, minimal logger or
Log::Log4perl if it is installed. Possible values are the same as
the "Log::Log4perl" levels: "TRACE", "DEBUG", "INFO", "WARN",
"ERROR", and "FATAL". The default is "INFO".
GIT_COMMAND
The path to the "git" binary to use for the Git features. The
default is "/usr/local/bin/git".
Methods
run( ARGS )
Just do it.
The "run" method returns 0 on success and a positive number on
failure. See the section on EXIT CODES for details on the values.
CPAN.pm sends all the good stuff either to STDOUT, or to a temp
file if $CPAN::Be_Silent is set. I have to intercept that output so
I can find out what happened.
Stolen from File::Path::Expand
EXIT VALUES
The script exits with zero if it thinks that everything worked, or a
positive number if it thinks that something failed. Note, however, that
in some cases it has to divine a failure by the output of things it
does not control. For now, the exit codes are vague:
1 An unknown error
2 The was an external problem
4 There was an internal problem with the script
8 A module failed to install
TO DO
* There is initial support for Log4perl if it is available, but I
haven't gone through everything to make the NullLogger work out
correctly if Log4perl is not installed.
* When I capture CPAN.pm output, I need to check for errors and report
them to the user.
* Warnings switch
* Check then exit
BUGS
* none noted
SEE ALSO
CPAN(3), App::cpanminus(3)
SOURCE AVAILABILITY
This code is in Github in the CPAN.pm repository:
https://github.com/andk/cpanpm
The source used to be tracked separately in another GitHub repo, but
the canonical source is now in the above repo.
CREDITS
Japheth Cleaver added the bits to allow a forced install ("-f").
Jim Brandt suggested and provided the initial implementation for the
up-to-date and Changes features.
Adam Kennedy pointed out that exit() causes problems on Windows where
this script ends up with a .bat extension
David Golden helps integrate this into the "CPAN.pm" repos.
Jim Keenan fixed up various issues with _download
AUTHOR
brian d foy, "<bdfoy@cpan.org>"
COPYRIGHT
Copyright (c) 2001-2021, brian d foy, All Rights Reserved.
You may redistribute this under the same terms as Perl itself.
perl v5.38.2 2023-11-28 App::Cpan(3pm)
perl 5.38.2 - Generated Mon Dec 2 18:57:40 CST 2024