r1 - 26 May 2008 - TWikiGuest

Interactive Mode
CPAN::Shell
autobundle
recompile
The four CPAN::* Classes: Author, Bundle, Module, Distribution
Programmer's interface
Methods in the other Classes
Cache Manager
Bundles
Prerequisites
Finding packages and VERSION
Debugging
Floppy, Zip, Offline Mode

CONFIGURATION

Note on urllist parameter's format
urllist parameter has CD-ROM support

SECURITY
EXPORT
POPULATE AN INSTALLATION WITH LOTS OF MODULES
WORKING WITH CPAN.pm BEHIND FIREWALLS

Three basic types of firewalls
Configuring lynx or ncftp for going through a firewall

FAQ
BUGS
AUTHOR
TRANSLATIONS
SEE ALSO

NAME

CPAN - query, download and build perl modules from CPAN sites

voltar para o topo

SYNOPSIS

Interactive mode:

  perl -MCPAN -e shell;

Batch mode:

  use CPAN;

  autobundle, clean, install, make, recompile, test

voltar para o topo

STATUS

This module will eventually be replaced by CPANPLUS. CPANPLUS is kind of a modern rewrite from ground up with greater extensibility and more features but no full compatibility. If you're new to CPAN.pm, you probably should investigate if CPANPLUS is the better choice for you. If you're already used to CPAN.pm you're welcome to continue using it, if you accept that its development is mostly (though not completely) stalled.

voltar para o topo

DESCRIPTION

The CPAN module is designed to automate the make and install of perl modules and extensions. It includes some primitive searching capabilities and knows how to use Net::FTP or LWP (or lynx or an external ftp client) to fetch the raw data from the net. Modules are fetched from one or more of the mirrored CPAN (Comprehensive Perl Archive Network) sites and unpacked in a dedicated directory. The CPAN module also supports the concept of named and versioned bundles of modules. Bundles simplify the handling of sets of related modules. See Bundles below. The package contains a session manager and a cache manager. There is no status retained between sessions. The session manager keeps track of what has been fetched, built and installed in the current session. The cache manager keeps track of the disk space occupied by the make processes and deletes excess space according to a simple FIFO mechanism. For extended searching capabilities there's a plugin for CPAN available, CPAN::WAIT. CPAN::WAIT is a full-text search engine that indexes all documents available in CPAN authors directories. If CPAN::WAIT is installed on your system, the interactive shell of CPAN.pm will enable the wq, wr, wd, wl, and wh commands which send queries to the WAIT server that has been configured for your installation. All other methods provided are accessible in a programmer style and in an interactive shell style.

Interactive Mode

The interactive mode is entered by running

    perl -MCPAN -e shell

which puts you into a readline interface. You will have the most fun if you install Term::ReadKey and Term::ReadLine to enjoy both history and command completion. Once you are on the command line, type 'h' and the rest should be self-explanatory. The function call shell takes two optional arguments, one is the prompt, the second is the default initial command line (the latter only works if a real ReadLine? interface module is installed). The most common uses of the interactive modes are

Searching for authors, bundles, distribution files and modules

There are corresponding one-letter commands a, b, d, and m

for each of the four categories and another, i for any of the

mentioned four. Each of the four entities is implemented as a class

with slightly differing methods for displaying an object.

Arguments you pass to these commands are either strings exactly matching

the identification string of an object or regular expressions that are

then matched case-insensitively against various attributes of the

objects. The parser recognizes a regular expression only if you

enclose it between two slashes.

The principle is that the number of found objects influences how an

item is displayed. If the search finds one item, the result is

displayed with the rather verbose method as_string, but if we find

more than one, we display each object with the terse method

<as_glimpse>.

make, test, install, clean modules or distributions

These commands take any number of arguments and investigate what is

necessary to perform the action. If the argument is a distribution

file name (recognized by embedded slashes), it is processed. If it is

a module, CPAN determines the distribution file in which this module

is included and processes that, following any dependencies named in

the module's Makefile.PL (this behavior is controlled by

prerequisites_policy.)

Any make or test are run unconditionally. An

  install <distribution_file>

also is run unconditionally. But for

  install <module>

CPAN checks if an install is actually needed for it and prints

module up to date in the case that the distribution file containing

the module doesn't need to be updated.

CPAN also keeps track of what it has done within the current session

and doesn't try to build a package a second time regardless if it

succeeded or not. The force command takes as a first argument the

method to invoke (currently: make, test, or install) and executes the

command from scratch.

Example:

    cpan> install OpenGL

    OpenGL is up to date.

    cpan> force install OpenGL

    Running make

    OpenGL-0.4/

    OpenGL-0.4/COPYRIGHT

    [...]

A clean command results in a

  make clean

being executed within the distribution file's working directory.

get, readme, look module or distribution

get downloads a distribution file without further action. readme

displays the README file of the associated distribution. Look gets

and untars (if not yet done) the distribution file, changes to the

appropriate directory and opens a subshell process in that directory.

ls author

ls lists all distribution files in and below an author's CPAN

directory. Only those files that contain modules are listed and if

there is more than one for any given module, only the most recent one

is listed.

Signals

CPAN.pm installs signal handlers for SIGINT and SIGTERM. While you are

in the cpan-shell it is intended that you can press ^C anytime and

return to the cpan-shell prompt. A SIGTERM will cause the cpan-shell

to clean up and leave the shell loop. You can emulate the effect of a

SIGTERM by sending two consecutive SIGINTs, which usually means by

pressing ^C twice.

CPAN.pm ignores a SIGPIPE. If the user sets inactivity_timeout, a

SIGALRM is used during the run of the perl Makefile.PL subprocess.

CPAN::Shell

The commands that are available in the shell interface are methods in the package CPAN::Shell. If you enter the shell command, all your input is split by the Text::ParseWords::shellwords() routine which acts like most shells do. The first word is being interpreted as the method to be called and the rest of the words are treated as arguments to this method. Continuation lines are supported if a line ends with a literal backslash.

autobundle

autobundle writes a bundle file into the $CPAN::Config->{cpan_home}/Bundle directory. The file contains a list of all modules that are both available from CPAN and currently installed within @INC. The name of the bundle file is based on the current date and a counter.

recompile

recompile() is a very special command in that it takes no argument and runs the make/test/install cycle with brute force over all installed dynamically loadable extensions (aka XS modules) with 'force' in effect. The primary purpose of this command is to finish a network installation. Imagine, you have a common source tree for two different architectures. You decide to do a completely independent fresh installation. You start on one architecture with the help of a Bundle file produced earlier. CPAN installs the whole Bundle for you, but when you try to repeat the job on the second architecture, CPAN responds with a "Foo up to date" message for all modules. So you invoke CPAN's recompile on the second architecture and you're done. Another popular use for recompile is to act as a rescue in case your perl breaks binary compatibility. If one of the modules that CPAN uses is in turn depending on binary compatibility (so you cannot run CPAN commands), then you should try the CPAN::Nox module for recovery.

The four `CPAN::*` Classes: Author, Bundle, Module, Distribution

Although it may be considered internal, the class hierarchy does matter for both users and programmer. CPAN.pm deals with above mentioned four classes, and all those classes share a set of methods. A classical single polymorphism is in effect. A metaclass object registers all objects of all kinds and indexes them with a string. The strings referencing objects have a separated namespace (well, not completely separated):

         Namespace                         Class

   words containing a "/" (slash)      Distribution

    words starting with Bundle::          Bundle

          everything else            Module or Author

Modules know their associated Distribution objects. They always refer to the most recent official release. Developers may mark their releases as unstable development versions (by inserting an underbar into the module version number which will also be reflected in the distribution name when you run 'make dist'), so the really hottest and newest distribution is not always the default. If a module Foo circulates on CPAN in both version 1.23 and 1.23_90, CPAN.pm offers a convenient way to install version 1.23 by saying

    install Foo

This would install the complete distribution file (say BAR/Foo-1.23.tar.gz) with all accompanying material. But if you would like to install version 1.23_90, you need to know where the distribution file resides on CPAN relative to the authors/id/ directory. If the author is BAR, this might be BAR/Foo-1.23_90.tar.gz; so you would have to say

    install BAR/Foo-1.23_90.tar.gz

The first example will be driven by an object of the class CPAN::Module, the second by an object of class CPAN::Distribution.

Programmer's interface

If you do not enter the shell, the available shell commands are both available as methods (CPAN::Shell->install(...)) and as functions in the calling package (install(...)). There's currently only one class that has a stable interface - CPAN::Shell. All commands that are available in the CPAN shell are methods of the class CPAN::Shell. Each of the commands that produce listings of modules (r, autobundle, u) also return a list of the IDs of all modules within the list.

expand($type,@things)

The IDs of all objects available within a program are strings that can

be expanded to the corresponding real objects with the

CPAN::Shell->expand("Module",@things) method. Expand returns a

list of CPAN::Module objects according to the @things arguments

given. In scalar context it only returns the first element of the

list.

expandany(@things)

Like expand, but returns objects of the appropriate type, i.e.

CPAN::Bundle objects for bundles, CPAN::Module objects for modules and

CPAN::Distribution objects fro distributions.

Programming Examples

This enables the programmer to do operations that combine

functionalities that are available in the shell.

    # install everything that is outdated on my disk:

    perl -MCPAN -e 'CPAN::Shell->install(CPAN::Shell->r)'

    # install my favorite programs if necessary:

    for $mod (qw(Net::FTP Digest::MD5 Data::Dumper)){

        my $obj = CPAN::Shell->expand('Module',$mod);

        $obj->install;

    # list all modules on my disk that have no VERSION number

    for $mod (CPAN::Shell->expand("Module","/./")){

        next unless $mod->inst_file;

        # MakeMaker convention for undefined $VERSION:

        next unless $mod->inst_version eq "undef";

        print "No VERSION in ", $mod->id, "\n";

    # find out which distribution on CPAN contains a module:

    print CPAN::Shell->expand("Module","Apache::Constants")->cpan_file

Or if you want to write a cronjob to watch The CPAN, you could list

all modules that need updating. First a quick and dirty way:

    perl -e 'use CPAN; CPAN::Shell->r;'

If you don't want to get any output in the case that all modules are

up to date, you can parse the output of above command for the regular

expression //modules are up to date// and decide to mail the output

only if it doesn't match. Ick?

If you prefer to do it more in a programmer style in one single

process, maybe something like this suits you better:

  # list all modules on my disk that have newer versions on CPAN

  for $mod (CPAN::Shell->expand("Module","/./")){

    next unless $mod->inst_file;

    next if $mod->uptodate;

    printf "Module %s is installed as %s, could be updated to %s from CPAN\n",

        $mod->id, $mod->inst_version, $mod->cpan_version;

If that gives you too much output every day, you maybe only want to

watch for three modules. You can write

  for $mod (CPAN::Shell->expand("Module","/Apache|LWP|CGI/")){

as the first line instead. Or you can combine some of the above

tricks:

  # watch only for a new mod_perl module

  $mod = CPAN::Shell->expand("Module","mod_perl");

  exit if $mod->uptodate;

  # new mod_perl arrived, let me know all update recommendations

  CPAN::Shell->r;

Methods in the other Classes

The programming interface for the classes CPAN::Module, CPAN::Distribution, CPAN::Bundle, and CPAN::Author is still considered beta and partially even alpha. In the following paragraphs only those methods are documented that have proven useful over a longer time and thus are unlikely to change.

CPAN::Author::as_glimpse()

Returns a one-line description of the author

CPAN::Author::as_string()

Returns a multi-line description of the author

CPAN::Author::email()

Returns the author's email address

CPAN::Author::fullname()

Returns the author's name

CPAN::Author::name()

An alias for fullname

CPAN::Bundle::as_glimpse()

Returns a one-line description of the bundle

CPAN::Bundle::as_string()

Returns a multi-line description of the bundle

CPAN::Bundle::clean()

Recursively runs the clean method on all items contained in the bundle.

CPAN::Bundle::contains()

Returns a list of objects' IDs contained in a bundle. The associated

objects may be bundles, modules or distributions.

CPAN::Bundle::force($method,@args)

Forces CPAN to perform a task that normally would have failed. Force

takes as arguments a method name to be called and any number of

additional arguments that should be passed to the called method. The

internals of the object get the needed changes so that CPAN.pm does

not refuse to take the action. The force is passed recursively to

all contained objects.

CPAN::Bundle::get()

Recursively runs the get method on all items contained in the bundle

CPAN::Bundle::inst_file()

Returns the highest installed version of the bundle in either @INC or

$CPAN::Config-{cpan_home}>. Note that this is different from

CPAN::Module::inst_file.

CPAN::Bundle::inst_version()

Like CPAN::Bundle::inst_file, but returns the $VERSION

CPAN::Bundle::uptodate()

Returns 1 if the bundle itself and all its members are uptodate.

CPAN::Bundle::install()

Recursively runs the install method on all items contained in the bundle

CPAN::Bundle::make()

Recursively runs the make method on all items contained in the bundle

CPAN::Bundle::readme()

Recursively runs the readme method on all items contained in the bundle

CPAN::Bundle::test()

Recursively runs the test method on all items contained in the bundle

CPAN::Distribution::as_glimpse()

Returns a one-line description of the distribution

CPAN::Distribution::as_string()

Returns a multi-line description of the distribution

CPAN::Distribution::clean()

Changes to the directory where the distribution has been unpacked and

runs make clean there.

CPAN::Distribution::containsmods()

Returns a list of IDs of modules contained in a distribution file.

Only works for distributions listed in the 02packages.details.txt.gz

file. This typically means that only the most recent version of a

distribution is covered.

CPAN::Distribution::cvs_import()

Changes to the directory where the distribution has been unpacked and

runs something like

    cvs -d $cvs_root import -m $cvs_log $cvs_dir $userid v$version

there.

CPAN::Distribution::dir()

Returns the directory into which this distribution has been unpacked.

CPAN::Distribution::force($method,@args)

Forces CPAN to perform a task that normally would have failed. Force

takes as arguments a method name to be called and any number of

additional arguments that should be passed to the called method. The

internals of the object get the needed changes so that CPAN.pm does

not refuse to take the action.

CPAN::Distribution::get()

Downloads the distribution from CPAN and unpacks it. Does nothing if

the distribution has already been downloaded and unpacked within the

current session.

CPAN::Distribution::install()

Changes to the directory where the distribution has been unpacked and

runs the external command make install there. If make has not

yet been run, it will be run first. A make test will be issued in

any case and if this fails, the install will be canceled. The

cancellation can be avoided by letting force run the install for

you.

CPAN::Distribution::isa_perl()

Returns 1 if this distribution file seems to be a perl distribution.

Normally this is derived from the file name only, but the index from

CPAN can contain a hint to achieve a return value of true for other

filenames too.

CPAN::Distribution::look()

Changes to the directory where the distribution has been unpacked and

opens a subshell there. Exiting the subshell returns.

CPAN::Distribution::make()

First runs the get method to make sure the distribution is

downloaded and unpacked. Changes to the directory where the

distribution has been unpacked and runs the external commands perl

Makefile.PL> and make there.

CPAN::Distribution::prereq_pm()

Returns the hash reference that has been announced by a distribution

as the PREREQ_PM hash in the Makefile.PL. Note: works only after an

attempt has been made to make the distribution. Returns undef

otherwise.

CPAN::Distribution::readme()

Downloads the README file associated with a distribution and runs it

through the pager specified in $CPAN::Config-{pager}>.

CPAN::Distribution::test()

Changes to the directory where the distribution has been unpacked and

runs make test there.

CPAN::Distribution::uptodate()

Returns 1 if all the modules contained in the distribution are

uptodate. Relies on containsmods.

CPAN::Index::force_reload()

Forces a reload of all indices.

CPAN::Index::reload()

Reloads all indices if they have been read more than

$CPAN::Config-{index_expire}> days.

CPAN::InfoObj::dump()

CPAN::Author, CPAN::Bundle, CPAN::Module, and CPAN::Distribution

inherit this method. It prints the data structure associated with an

object. Useful for debugging. Note: the data structure is considered

internal and thus subject to change without notice.

CPAN::Module::as_glimpse()

Returns a one-line description of the module

CPAN::Module::as_string()

Returns a multi-line description of the module

CPAN::Module::clean()

Runs a clean on the distribution associated with this module.

CPAN::Module::cpan_file()

Returns the filename on CPAN that is associated with the module.

CPAN::Module::cpan_version()

Returns the latest version of this module available on CPAN.

CPAN::Module::cvs_import()

Runs a cvs_import on the distribution associated with this module.

CPAN::Module::description()

Returns a 44 character description of this module. Only available for

modules listed in The Module List (CPAN/modules/00modlist.long.html

or 00modlist.long.txt.gz)

CPAN::Module::force($method,@args)

Forces CPAN to perform a task that normally would have failed. Force

takes as arguments a method name to be called and any number of

additional arguments that should be passed to the called method. The

internals of the object get the needed changes so that CPAN.pm does

not refuse to take the action.

CPAN::Module::get()

Runs a get on the distribution associated with this module.

CPAN::Module::inst_file()

Returns the filename of the module found in @INC. The first file found

is reported just like perl itself stops searching @INC when it finds a

module.

CPAN::Module::inst_version()

Returns the version number of the module in readable format.

CPAN::Module::install()

Runs an install on the distribution associated with this module.

CPAN::Module::look()

Changes to the directory where the distribution associated with this

module has been unpacked and opens a subshell there. Exiting the

subshell returns.

CPAN::Module::make()

Runs a make on the distribution associated with this module.

CPAN::Module::manpage_headline()

If module is installed, peeks into the module's manpage, reads the

headline and returns it. Moreover, if the module has been downloaded

within this session, does the equivalent on the downloaded module even

if it is not installed.

CPAN::Module::readme()

Runs a readme on the distribution associated with this module.

CPAN::Module::test()

Runs a test on the distribution associated with this module.

CPAN::Module::uptodate()

Returns 1 if the module is installed and up-to-date.

CPAN::Module::userid()

Returns the author's ID of the module.

Cache Manager

Currently the cache manager only keeps track of the build directory ($CPAN::Config->{build_dir}). It is a simple FIFO mechanism that deletes complete directories below build_dir as soon as the size of all directories there gets bigger than $CPAN::Config->{build_cache} (in MB). The contents of this cache may be used for later re-installations that you intend to do manually, but will never be trusted by CPAN itself. This is due to the fact that the user might use these directories for building modules on different architectures. There is another directory ($CPAN::Config->{keep_source_where}) where the original distribution files are kept. This directory is not covered by the cache manager and must be controlled by the user. If you choose to have the same directory as build_dir and as keep_source_where directory, then your sources will be deleted with the same fifo mechanism.

Bundles

A bundle is just a perl module in the namespace Bundle:: that does not define any functions or methods. It usually only contains documentation. It starts like a perl module with a package declaration and a $VERSION variable. After that the pod section looks like any other pod with the only difference being that one special pod section exists starting with (verbatim):

        =head1 CONTENTS

In this pod section each line obeys the format

        Module_Name [Version_String] [- optional text]

The only required part is the first field, the name of a module (e.g. Foo::Bar, ie. not the name of the distribution file). The rest of the line is optional. The comment part is delimited by a dash just as in the man page header. The distribution of a bundle should follow the same convention as other distributions. Bundles are treated specially in the CPAN package. If you say 'install Bundle::Tkkit' (assuming such a bundle exists), CPAN will install all the modules in the CONTENTS section of the pod. You can install your own Bundles locally by placing a conformant Bundle file somewhere into your @INC path. The autobundle() command which is available in the shell interface does that for you by including all currently installed modules in a snapshot bundle file.

Prerequisites

If you have a local mirror of CPAN and can access all files with ``file:'' URLs, then you only need a perl better than perl5.003 to run this module. Otherwise Net::FTP is strongly recommended. LWP may be required for non-UNIX systems or if your nearest CPAN site is associated with a URL that is not ftp:. If you have neither Net::FTP nor LWP, there is a fallback mechanism implemented for an external ftp command or for an external lynx command.

Finding packages and VERSION

This module presumes that all packages on CPAN

    perl -MExtUtils::MakeMaker -le \

        'print MM->parse_version(shift)' filename

Debugging

The debugging of this module is a bit complex, because we have interferences of the software producing the indices on CPAN, of the mirroring process on CPAN, of packaging, of configuration, of synchronicity, and of bugs within CPAN.pm. For code debugging in interactive mode you can try ``o debug'' which will list options for debugging the various parts of the code. You should know that ``o debug'' has built-in completion support. For data debugging there is the dump command which takes the same arguments as make/test/install and outputs the object's Data::Dumper dump.

Floppy, Zip, Offline Mode

CPAN.pm works nicely without network too. If you maintain machines that are not networked at all, you should consider working with file: URLs. Of course, you have to collect your modules somewhere first. So you might use CPAN.pm to put together all you need on a networked machine. Then copy the $CPAN::Config->{keep_source_where} (but not $CPAN::Config->{build_dir}) directory on a floppy. This floppy is kind of a personal CPAN. CPAN.pm on the non-networked machines works nicely with this floppy. See also below the paragraph about CD-ROM support.

voltar para o topo

CONFIGURATION

When the CPAN module is used for the first time, a configuration dialog tries to determine a couple of site specific options. The result of the dialog is stored in a hash reference $CPAN::Config in a file CPAN/Config.pm. The default values defined in the CPAN/Config.pm file can be overridden in a user specific file: CPAN/MyConfig.pm. Such a file is best placed in $HOME/.cpan/CPAN/MyConfig.pm, because $HOME/.cpan is added to the search path of the CPAN module before the use() or require() statements. The configuration dialog can be started any time later again by issueing the command o conf init in the CPAN shell. Currently the following keys in the hash reference $CPAN::Config are defined:

  build_cache        size of cache for directories to build modules

  build_dir          locally accessible directory to build modules

  index_expire       after this many days refetch index files

  cache_metadata     use serializer to cache metadata

  cpan_home          local directory reserved for this package

  dontload_hash      anonymous hash: modules in the keys will not be

                     loaded by the CPAN::has_inst() routine

  gzip               location of external program gzip

  histfile           file to maintain history between sessions

  histsize           maximum number of lines to keep in histfile

  inactivity_timeout breaks interactive Makefile.PLs after this

                     many seconds inactivity. Set to 0 to never break.

  inhibit_startup_message

                     if true, does not print the startup message

  keep_source_where  directory in which to keep the source (if we do)

  make               location of external make program

  make_arg           arguments that should always be passed to 'make'

  make_install_arg   same as make_arg for 'make install'

  makepl_arg         arguments passed to 'perl Makefile.PL'

  pager              location of external program more (or any pager)

  prerequisites_policy

                     what to do if you are missing module prerequisites

                     ('follow' automatically, 'ask' me, or 'ignore')

  proxy_user         username for accessing an authenticating proxy

  proxy_pass         password for accessing an authenticating proxy

  scan_cache         controls scanning of cache ('atstart' or 'never')

  tar                location of external program tar

  term_is_latin      if true internal UTF-8 is translated to ISO-8859-1

                     (and nonsense for characters outside latin range)

  unzip              location of external program unzip

  urllist            arrayref to nearby CPAN sites (or equivalent locations)

  wait_list          arrayref to a wait server to try (See CPAN::WAIT)

  ftp_proxy,      }  the three usual variables for configuring

    http_proxy,   }  proxy requests. Both as CPAN::Config variables

    no_proxy      }  and as environment variables configurable.

You can set and query each of these options interactively in the cpan shell with the command set defined within the o conf command:

o conf <scalar option>: prints the current value of the scalar option
o conf <scalar option> <value>: Sets the value of the scalar option to value
o conf <list option>: prints the current value of the list option in MakeMaker? 's; neatvalue format.
o conf <list option> [shift|pop]: shifts or pops the array in the list option variable
o conf <list option> [unshift|push|splice] <list>: works like the corresponding perl commands.

Note on urllist parameter's format

urllist parameters are URLs according to RFC 1738. We do a little guessing if your URL is not compliant, but if you have problems with file URLs, please try the correct format. Either:

    file://localhost/whatever/ftp/pub/CPAN/

    file:///home/ftp/pub/CPAN/

urllist parameter has CD-ROM support

The urllist parameter of the configuration table contains a list of URLs that are to be used for downloading. If the list contains any file URLs, CPAN always tries to get files from there first. This feature is disabled for index files. So the recommendation for the owner of a CD-ROM with CPAN contents is: include your local, possibly outdated CD-ROM as a file URL at the end of urllist, e.g.

  o conf urllist push file://localhost/CDROM/CPAN

CPAN.pm will then fetch the index files from one of the CPAN sites that come at the beginning of urllist. It will later check for each module if there is a local copy of the most recent version. Another peculiarity of urllist is that the site that we could successfully fetch the last file from automatically gets a preference token and is tried as the first site for the next request. So if you add a new site at runtime it may happen that the previously preferred site will be tried another time. This means that if you want to disallow a site for the next transfer, it must be explicitly removed from urllist.

voltar para o topo

SECURITY

There's no strong security layer in CPAN.pm. CPAN.pm helps you to install foreign, unmasked, unsigned code on your machine. We compare to a checksum that comes from the net just as the distribution file itself. If somebody has managed to tamper with the distribution file, they may have as well tampered with the CHECKSUMS file. Future development will go towards strong authentication.

voltar para o topo

EXPORT

Most functions in package CPAN are exported per default. The reason for this is that the primary use is intended for the cpan shell or for one-liners.

voltar para o topo

POPULATE AN INSTALLATION WITH LOTS OF MODULES

Populating a freshly installed perl with my favorite modules is pretty easy if you maintain a private bundle definition file. To get a useful blueprint of a bundle definition file, the command autobundle can be used on the CPAN shell command line. This command writes a bundle definition file for all modules that are installed for the currently running perl interpreter. It's recommended to run this command only once and from then on maintain the file manually under a private name, say Bundle/my_bundle.pm. With a clever bundle file you can then simply say

    cpan> install Bundle::my_bundle

then answer a few questions and then go out for a coffee. Maintaining a bundle definition file means keeping track of two things: dependencies and interactivity. CPAN.pm sometimes fails on calculating dependencies because not all modules define all MakeMaker? attributes correctly, so a bundle definition file should specify prerequisites as early as possible. On the other hand, it's a bit annoying that many distributions need some interactive configuring. So what I try to accomplish in my private bundle file is to have the packages that need to be configured early in the file and the gentle ones later, so I can go out after a few minutes and leave CPAN.pm untended.

voltar para o topo

WORKING WITH CPAN.pm BEHIND FIREWALLS

Thanks to Graham Barr for contributing the following paragraphs about the interaction between perl, and various firewall configurations. For further informations on firewalls, it is recommended to consult the documentation that comes with the ncftp program. If you are unable to go through the firewall with a simple Perl setup, it is very likely that you can configure ncftp so that it works for your firewall.

Three basic types of firewalls

Firewalls can be categorized into three basic types.

http firewall: This is where the firewall machine runs a web server and to access the; outside world you must do it via the web server. If you set environment; variables like http_proxy or ftp_proxy to a values beginning with http://; or in your web browser you have to set proxy information then you know; you are running an http firewall.; To access servers outside these types of firewalls with perl (even for; ftp) you will need to use LWP.
ftp firewall: This where the firewall machine runs an ftp server. This kind of; firewall will only let you access ftp servers outside the firewall.; This is usually done by connecting to the firewall with ftp, then; entering a username like ``user@outside.host.com''; To access servers outside these type of firewalls with perl you; will need to use Net::FTP.
One way visibility: I say one way visibility as these firewalls try to make themselves look; invisible to the users inside the firewall. An FTP data connection is; normally created by sending the remote server your IP address and then; listening for the connection. But the remote server will not be able to; connect to you because of the firewall. So for these types of firewall; FTP connections need to be done in a passive mode.; There are two that I can think off.

Configuring lynx or ncftp for going through a firewall

If you can go through your firewall with e.g. lynx, presumably with a command such as

    /usr/local/bin/lynx -pscott:tiger

then you would configure CPAN.pm with the command

    o conf lynx "/usr/local/bin/lynx -pscott:tiger"

That's all. Similarly for ncftp or ftp, you would configure something like

    o conf ncftp "/usr/bin/ncftp -f /home/scott/ncftplogin.cfg"

Your mileage may vary...

voltar para o topo

FAQ

)

CPAN

UNINST=1

make install

  o conf make_install_arg UNINST=1

)

UNINST=1

)

    ./Configure -Dprefix=/usr/local/perl-5.6.78.9

    cpan> install Bundle::mybundle

)

  o conf make_arg "| tee -ai /root/.cpan/logs/make.out"

  o conf make_install_arg "| tee -ai /root/.cpan/logs/make_install.out"

)

  o conf makepl_arg "LIB=~/myperl/lib \

                    INSTALLMAN1DIR=~/myperl/man/man1 \

                    INSTALLMAN3DIR=~/myperl/man/man3"

  install Sybase::Sybperl

o conf

o conf commit

  use lib "$ENV{HOME}/myperl/lib";

PERL5LIB?

)

  look Sybase::Sybperl

)

CPAN

MakeMaker?

CPAN

)

CPAN

)

CPAN

RedHat?

on

On

)

CPAN

    cpan> ! $CPAN::Config->{term_is_latin}=1

voltar para o topo

BUGS

We should give coverage for all of the CPAN and not just the PAUSE part, right? In this discussion CPAN and PAUSE have become equal -- but they are not. PAUSE is authors/, modules/ and scripts/. CPAN is PAUSE plus the clpa/, doc/, misc/, ports/, and src/. Future development should be directed towards a better integration of the other parts. If a Makefile.PL requires special customization of libraries, prompts the user for special input, etc. then you may find CPAN is not able to build the distribution. In that case, you should attempt the traditional method of building a Perl module package from a shell.

voltar para o topo

AUTHOR

Andreas Koenig <andreas.koenig@anima.de>

voltar para o topo

TRANSLATIONS

Kawai,Takanori provides a Japanese translation of this manpage at http://member.nifty.ne.jp/hippo2000/perltips/CPAN.htm

voltar para o topo

Pesquisar

Documentação

Artigos

Planeta

Eventos

Comunidade

NAME

SYNOPSIS

STATUS

DESCRIPTION

Interactive Mode

CPAN::Shell

autobundle

recompile

The four `CPAN::*` Classes: Author, Bundle, Module, Distribution

Programmer's interface

Methods in the other Classes

Cache Manager

Bundles

Prerequisites

Finding packages and VERSION

Debugging

Floppy, Zip, Offline Mode

CONFIGURATION

Note on urllist parameter's format

urllist parameter has CD-ROM support

SECURITY

EXPORT

POPULATE AN INSTALLATION WITH LOTS OF MODULES

WORKING WITH CPAN.pm BEHIND FIREWALLS

Three basic types of firewalls

Configuring lynx or ncftp for going through a firewall

FAQ

BUGS

AUTHOR

TRANSLATIONS

SEE ALSO