cpan.3

视频监控网络部分的协议ddns,的模块的实现代码,请大家大胆指正.

.IX Subsection "Configuration for individual distributions (Distroprefs)"
(\fBNote:\fR This feature has been introduced in \s-1CPAN\s0.pm 1.8854 and is
still considered beta quality)
.PP
Distributions on the \s-1CPAN\s0 usually behave according to what we call the
\&\s-1CPAN\s0 mantra. Or since the event of Module::Build we should talk about
two mantras:
.PP
.Vb 4
\&    perl Makefile.PL     perl Build.PL
\&    make                 ./Build
\&    make test            ./Build test
\&    make install         ./Build install
.Ve
.PP
But some modules cannot be built with this mantra. They try to get
some extra data from the user via the environment, extra arguments or
interactively thus disturbing the installation of large bundles like
Phalanx100 or modules with many dependencies like Plagger.
.PP
The distroprefs system of \f(CW\*(C`CPAN.pm\*(C'\fR addresses this problem by
allowing the user to specify extra informations and recipes in \s-1YAML\s0
files to either
.IP "\(bu" 4
pass additional arguments to one of the four commands,
.IP "\(bu" 4
set environment variables
.IP "\(bu" 4
instantiate an Expect object that reads from the console, waits for
some regular expressions and enters some answers
.IP "\(bu" 4
temporarily override assorted \f(CW\*(C`CPAN.pm\*(C'\fR configuration variables
.IP "\(bu" 4
specify dependencies that the original maintainer forgot to specify
.IP "\(bu" 4
disable the installation of an object altogether
.PP
See the \s-1YAML\s0 and Data::Dumper files that come with the \f(CW\*(C`CPAN.pm\*(C'\fR
distribution in the \f(CW\*(C`distroprefs/\*(C'\fR directory for examples.
.Sh "Filenames"
.IX Subsection "Filenames"
The \s-1YAML\s0 files themselves must have the \f(CW\*(C`.yml\*(C'\fR extension, all other
files are ignored (for two exceptions see \fIFallback Data::Dumper and
Storable\fR below). The containing directory can be specified in
\&\f(CW\*(C`CPAN.pm\*(C'\fR in the \f(CW\*(C`prefs_dir\*(C'\fR config variable. Try \f(CW\*(C`o conf init
prefs_dir\*(C'\fR in the \s-1CPAN\s0 shell to set and activate the distroprefs
system.
.PP
Every \s-1YAML\s0 file may contain arbitrary documents according to the \s-1YAML\s0
specification and every single document is treated as an entity that
can specify the treatment of a single distribution.
.PP
The names of the files can be picked freely, \f(CW\*(C`CPAN.pm\*(C'\fR always reads
all files (in alphabetical order) and takes the key \f(CW\*(C`match\*(C'\fR (see
below in \fILanguage Specs\fR) as a hashref containing match criteria
that determine if the current distribution matches the \s-1YAML\s0 document
or not.
.Sh "Fallback Data::Dumper and Storable"
.IX Subsection "Fallback Data::Dumper and Storable"
If neither your configured \f(CW\*(C`yaml_module\*(C'\fR nor \s-1YAML\s0.pm is installed
\&\s-1CPAN\s0.pm falls back to using Data::Dumper and Storable and looks for
files with the extensions \f(CW\*(C`.dd\*(C'\fR or \f(CW\*(C`.st\*(C'\fR in the \f(CW\*(C`prefs_dir\*(C'\fR
directory. These files are expected to contain one or more hashrefs.
For Data::Dumper generated files, this is expected to be done with by
defining \f(CW$VAR1\fR, \f(CW$VAR2\fR, etc. The \s-1YAML\s0 shell would produce these
with the command
.PP
.Vb 1
\&    ysh < somefile.yml > somefile.dd
.Ve
.PP
For Storable files the rule is that they must be constructed such that
\&\f(CW\*(C`Storable::retrieve(file)\*(C'\fR returns an array reference and the array
elements represent one distropref object each. The conversion from
\&\s-1YAML\s0 would look like so:
.PP
.Vb 3
\&    perl \-MYAML=LoadFile \-MStorable=nstore \-e \*(Aq
\&        @y=LoadFile(shift);
\&        nstore(\e@y, shift)\*(Aq somefile.yml somefile.st
.Ve
.PP
In bootstrapping situations it is usually sufficient to translate only
a few \s-1YAML\s0 files to Data::Dumper for the crucial modules like
\&\f(CW\*(C`YAML::Syck\*(C'\fR, \f(CW\*(C`YAML.pm\*(C'\fR and \f(CW\*(C`Expect.pm\*(C'\fR. If you prefer Storable
over Data::Dumper, remember to pull out a Storable version that writes
an older format than all the other Storable versions that will need to
read them.
.Sh "Blueprint"
.IX Subsection "Blueprint"
The following example contains all supported keywords and structures
with the exception of \f(CW\*(C`eexpect\*(C'\fR which can be used instead of
\&\f(CW\*(C`expect\*(C'\fR.
.PP
.Vb 10
\&  \-\-\-
\&  comment: "Demo"
\&  match:
\&    module: "Dancing::Queen"
\&    distribution: "^CHACHACHA/Dancing\-"
\&    perl: "/usr/local/cariba\-perl/bin/perl"
\&    perlconfig:
\&      archname: "freebsd"
\&  disabled: 1
\&  cpanconfig:
\&    make: gmake
\&  pl:
\&    args:
\&      \- "\-\-somearg=specialcase"
\&
\&    env: {}
\&
\&    expect:
\&      \- "Which is your favorite fruit"
\&      \- "apple\en"
\&
\&  make:
\&    args:
\&      \- all
\&      \- extra\-all
\&
\&    env: {}
\&
\&    expect: []
\&
\&    commendline: "echo SKIPPING make"
\&
\&  test:
\&    args: []
\&
\&    env: {}
\&
\&    expect: []
\&
\&  install:
\&    args: []
\&
\&    env:
\&      WANT_TO_INSTALL: YES
\&
\&    expect:
\&      \- "Do you really want to install"
\&      \- "y\en"
\&
\&  patches:
\&    \- "ABCDE/Fedcba\-3.14\-ABCDE\-01.patch"
\&
\&  depends:
\&    configure_requires:
\&      LWP: 5.8
\&    build_requires:
\&      Test::Exception: 0.25
\&    requires:
\&      Spiffy: 0.30
.Ve
.Sh "Language Specs"
.IX Subsection "Language Specs"
Every \s-1YAML\s0 document represents a single hash reference. The valid keys
in this hash are as follows:
.IP "comment [scalar]" 4
.IX Item "comment [scalar]"
A comment
.IP "cpanconfig [hash]" 4
.IX Item "cpanconfig [hash]"
Temporarily override assorted \f(CW\*(C`CPAN.pm\*(C'\fR configuration variables.
.Sp
Supported are: \f(CW\*(C`build_requires_install_policy\*(C'\fR, \f(CW\*(C`check_sigs\*(C'\fR,
\&\f(CW\*(C`make\*(C'\fR, \f(CW\*(C`make_install_make_command\*(C'\fR, \f(CW\*(C`prefer_installer\*(C'\fR,
\&\f(CW\*(C`test_report\*(C'\fR. Please report as a bug when you need another one
supported.
.IP "depends [hash] *** \s-1EXPERIMENTAL\s0 \s-1FEATURE\s0 ***" 4
.IX Item "depends [hash] *** EXPERIMENTAL FEATURE ***"
All three types, namely \f(CW\*(C`configure_requires\*(C'\fR, \f(CW\*(C`build_requires\*(C'\fR, and
\&\f(CW\*(C`requires\*(C'\fR are supported in the way specified in the \s-1META\s0.yml
specification. The current implementation \fImerges\fR the specified
dependencies with those declared by the package maintainer. In a
future implementation this may be changed to override the original
declaration.
.IP "disabled [boolean]" 4
.IX Item "disabled [boolean]"
Specifies that this distribution shall not be processed at all.
.IP "goto [string]" 4
.IX Item "goto [string]"
The canonical name of a delegate distribution that shall be installed
instead. Useful when a new version, although it tests \s-1OK\s0 itself,
breaks something else or a developer release or a fork is already
uploaded that is better than the last released version.
.IP "install [hash]" 4
.IX Item "install [hash]"
Processing instructions for the \f(CW\*(C`make install\*(C'\fR or \f(CW\*(C`./Build install\*(C'\fR
phase of the \s-1CPAN\s0 mantra. See below under \fIProcessiong Instructions\fR.
.IP "make [hash]" 4
.IX Item "make [hash]"
Processing instructions for the \f(CW\*(C`make\*(C'\fR or \f(CW\*(C`./Build\*(C'\fR phase of the
\&\s-1CPAN\s0 mantra. See below under \fIProcessiong Instructions\fR.
.IP "match [hash]" 4
.IX Item "match [hash]"
A hashref with one or more of the keys \f(CW\*(C`distribution\*(C'\fR, \f(CW\*(C`modules\*(C'\fR,
\&\f(CW\*(C`perl\*(C'\fR, and \f(CW\*(C`perlconfig\*(C'\fR that specify if a document is targeted at a
specific \s-1CPAN\s0 distribution or installation.
.Sp
The corresponding values are interpreted as regular expressions. The
\&\f(CW\*(C`distribution\*(C'\fR related one will be matched against the canonical
distribution name, e.g. \*(L"AUTHOR/Foo\-Bar\-3.14.tar.gz\*(R".
.Sp
The \f(CW\*(C`module\*(C'\fR related one will be matched against \fIall\fR modules
contained in the distribution until one module matches.
.Sp
The \f(CW\*(C`perl\*(C'\fR related one will be matched against \f(CW$^X\fR (but with the
absolute path).
.Sp
The value associated with \f(CW\*(C`perlconfig\*(C'\fR is itself a hashref that is
matched against corresponding values in the \f(CW%Config::Config\fR hash
living in the \f(CW\*(C` Config.pm \*(C'\fR module.
.Sp
If more than one restriction of \f(CW\*(C`module\*(C'\fR, \f(CW\*(C`distribution\*(C'\fR, and
\&\f(CW\*(C`perl\*(C'\fR is specified, the results of the separately computed match
values must all match. If this is the case then the hashref
represented by the \s-1YAML\s0 document is returned as the preference
structure for the current distribution.
.IP "patches [array]" 4
.IX Item "patches [array]"
An array of patches on \s-1CPAN\s0 or on the local disk to be applied in
order via the external patch program. If the value for the \f(CW\*(C`\-p\*(C'\fR
parameter is \f(CW0\fR or \f(CW1\fR is determined by reading the patch
beforehand.
.Sp
Note: if the \f(CW\*(C`applypatch\*(C'\fR program is installed and \f(CW\*(C`CPAN::Config\*(C'\fR
knows about it \fBand\fR a patch is written by the \f(CW\*(C`makepatch\*(C'\fR program,
then \f(CW\*(C`CPAN.pm\*(C'\fR lets \f(CW\*(C`applypatch\*(C'\fR apply the patch. Both \f(CW\*(C`makepatch\*(C'\fR
and \f(CW\*(C`applypatch\*(C'\fR are available from \s-1CPAN\s0 in the \f(CW\*(C`JV/makepatch\-*\*(C'\fR
distribution.
.IP "pl [hash]" 4
.IX Item "pl [hash]"
Processing instructions for the \f(CW\*(C`perl Makefile.PL\*(C'\fR or \f(CW\*(C`perl
Build.PL\*(C'\fR phase of the \s-1CPAN\s0 mantra. See below under \fIProcessiong
Instructions\fR.
.IP "test [hash]" 4
.IX Item "test [hash]"
Processing instructions for the \f(CW\*(C`make test\*(C'\fR or \f(CW\*(C`./Build test\*(C'\fR phase
of the \s-1CPAN\s0 mantra. See below under \fIProcessiong Instructions\fR.
.Sh "Processing Instructions"
.IX Subsection "Processing Instructions"
.IP "args [array]" 4
.IX Item "args [array]"
Arguments to be added to the command line
.IP "commandline" 4
.IX Item "commandline"
A full commandline that will be executed as it stands by a system
call. During the execution the environment variable \s-1PERL\s0 will is set
to $^X (but with an absolute path). If \f(CW\*(C`commandline\*(C'\fR is specified,
the content of \f(CW\*(C`args\*(C'\fR is not used.
.IP "eexpect [hash]" 4
.IX Item "eexpect [hash]"
Extended \f(CW\*(C`expect\*(C'\fR. This is a hash reference with four allowed keys,
\&\f(CW\*(C`mode\*(C'\fR, \f(CW\*(C`timeout\*(C'\fR, \f(CW\*(C`reuse\*(C'\fR, and \f(CW\*(C`talk\*(C'\fR.
.Sp
\&\f(CW\*(C`mode\*(C'\fR may have the values \f(CW\*(C`deterministic\*(C'\fR for the case where all
questions come in the order written down and \f(CW\*(C`anyorder\*(C'\fR for the case
where the questions may come in any order. The default mode is
\&\f(CW\*(C`deterministic\*(C'\fR.
.Sp
\&\f(CW\*(C`timeout\*(C'\fR denotes a timeout in seconds. Floating point timeouts are
\&\s-1OK\s0. In the case of a \f(CW\*(C`mode=deterministic\*(C'\fR the timeout denotes the
timeout per question, in the case of \f(CW\*(C`mode=anyorder\*(C'\fR it denotes the
timeout per byte received from the stream or questions.
.Sp
\&\f(CW\*(C`talk\*(C'\fR is a reference to an array that contains alternating questions
and answers. Questions are regular expressions and answers are literal
strings. The Expect module will then watch the stream coming from the
execution of the external program (\f(CW\*(C`perl Makefile.PL\*(C'\fR, \f(CW\*(C`perl
Build.PL\*(C'\fR, \f(CW\*(C`make\*(C'\fR, etc.).
.Sp
In the case of \f(CW\*(C`mode=deterministic\*(C'\fR the \s-1CPAN\s0.pm will inject the
according answer as soon as the stream matches the regular expression.
.Sp
In the case of \f(CW\*(C`mode=anyorder\*(C'\fR \s-1CPAN\s0.pm will answer a question as soon
as the timeout is reached for the next byte in the input stream. In
this mode you can use the \f(CW\*(C`reuse\*(C'\fR parameter to decide what shall
happen with a question-answer pair after it has been used. In the
default case (reuse=0) it is removed from the array, so it cannot be
used again accidentally. In this case, if you want to answer the
question \f(CW\*(C`Do you really want to do that\*(C'\fR several times, then it must
be included in the array at least as often as you want this answer to
be given. Setting the parameter \f(CW\*(C`reuse\*(C'\fR to 1 makes this repetition
unnecessary.
.IP "env [hash]" 4
.IX Item "env [hash]"
Environment variables to be set during the command
.IP "expect [array]" 4
.IX Item "expect [array]"
\&\f(CW\*(C`expect: <array>\*(C'\fR is a short notation for
.Sp
.Vb 4
\&  eexpect: