Perinci::CmdLine - Rinci/Riap-based command-line application framework
version 0.88
In your command-line script:
#!/usr/bin/perl use 5.010; use Log::Any '$log'; use Perinci::CmdLine; our %SPEC; $SPEC{foo} = { v => 1.1, summary => 'Does foo to your computer', args => { bar => { summary=>'Barrr', req=>1, schema=>['str*', {in=>[qw/aa bb cc/]}], }, baz => { summary=>'Bazzz', schema=>'str', }, }, }; sub foo { my %args = @_; $log->debugf("Arguments are %s", \%args); [200, "OK", $args{bar} . ($args{baz} ? "and $args{baz}" : "")]; } Perinci::CmdLine->new(url => '/main/foo')->run;
To run this program:
% foo --help ;# display help message % LANG=id_ID foo --help ;# display help message in Indonesian % foo --version ;# display version % foo --bar aa ;# run function and display the result % foo --bar aa --debug ;# turn on debug output % foo --baz x ;# fail because required argument 'bar' not specified
To do bash tab completion:
% complete -C foo foo ;# can be put in ~/.bashrc % foo <tab> ;# completes to --help, --version, --bar, --baz and others % foo --b<tab> ;# completes to --bar and --baz % foo --bar <tab> ;# completes to aa, bb, cc
See also the peri-run script which provides a command-line interface for Perinci::CmdLine.
Perinci::CmdLine is a command-line application framework. It parses command-line options and dispatches to one of your specified Perl functions, passing the command-line options and arguments to the function. It accesses functions via Riap protocol (using the Perinci::Access Riap client library) so you can access remote functions transparently. It utilizes Rinci metadata in the code so the amount of plumbing that you have to do is quite minimal. Basically most of the time you just need to write your "business logic" in your function (along with some metadata), and with a couple or several lines of script you have created a command-line interface with the following features:
Command-line options parsing
Non-scalar arguments (array, hash, other nested) can also be passed as JSON or YAML. For example, if the tags argument is defined as 'array', then all of below are equivalent:
tags
% mycmd --tags-yaml '[foo, bar, baz]' % mycmd --tags-yaml '["foo","bar","baz"]' % mycmd --tags foo --tags bar --tags baz
Help message (utilizing information from metadata, supports translation)
% mycmd --help % mycmd -h % mycmd -?
Tab completion for bash (including completion from remote code)
% complete -C mycmd mycmd % mycmd --he<tab> ; # --help % mycmd s<tab> ; # sub1, sub2, sub3 (if those are the specified subcommands) % mycmd sub1 -<tab> ; # list the options available for sub1 subcommand
Support for other shell might be added in the future upon request.
Undo/redo/history
If the function supports transaction (see Rinci::Transaction, Riap::Transaction) the framework will setup transaction and provide command to do undo (--undo) and redo (--redo) as well as seeing the undo/transaction list (--history) and clearing the list (--clear-history).
Version (--version, -v)
List available subcommands (--list, -l)
Configurable output format (--format, --format-options)
By default yaml, json, text, text-simple, text-pretty are recognized.
yaml
json
text
text-simple
text-pretty
Note that the each of the above command-line options (--help, --version, etc) can be renamed or disabled.
--help
--version
This module uses Log::Any and Log::Any::App for logging. This module uses Moo for OO.
Below is the description of how the framework determines what action and which function to call. (Currently lots of internal attributes are accessed directly, this might be rectified in the future.)
Actions. The _actions attribute is an array which contains the list of potential actions to choose, in order. It will then be filled out according to the command-line options specified. For example, if --help is specified, help action is shifted to the beginning of _actions. Likewise for --list, etc. Finally, the subcommand action (which means an action to call our function) is added to this list. After we are finished filling out the _actions array, the first action is chosen by running a method called run_<ACTION>. For example if the chosen action is help, run_help() is called. These run_* methods must execute the action, display the output, and return an exit code. Program will end with this exit code. A run_* method can choose to decline handling the action by returning undef, in which case the next action will be tried, and so on until a defined exit code is returned.
_actions
help
--list
subcommand
run_<ACTION>
run_help()
run_*
The subcommand action and determining which subcommand (function) to call. The subcommand action (implemented by run_subcommand()) is the one that actually does the real job, calling the function and displaying its result. The _subcommand attribute stores information on the subcommand to run, including its Riap URL. If there are subcommands, e.g.:
run_subcommand()
_subcommand
my $cmd = Perinci::CmdLine->new( subcommands => { sub1 => { url => '/MyApp/func1', }, sub2 => { url => '/MyApp/func2', }, }, );
then which subcommand to run is determined by the command-line argument, e.g.:
% myapp sub1 ...
then _subcommand attribute will contain {url=>'/MyApp/func1'}. When no subcommand is specified on the command line, run_subcommand() will decline handling the action and returning undef, and the next action e.g. help will be executed. But if default_subcommand attribute is set, run_subcommand() will run the default subcommand instead.
{url=>'/MyApp/func1'}
default_subcommand
When there are no subcommands, e.g.:
my $cmd = Perinci::CmdLine->new(url => '/MyApp/func');
_subcommand will simply contain {url=>'/MyApp/func'}.
{url=>'/MyApp/func'}
run_subcommand() will call the function specified in the url in the _subcommand using Perinci::Access. (Actually, run_help() or run_completion() can be called instead, depending on which action to run.)
url
Perinci::Access
run_completion()
Required if you only want to run one function. URL should point to a function entity.
Alternatively you can provide multiple functions from which the user can select using the first argument (see subcommands).
If unset, will be retrieved from function metadata when needed.
Should be a hash of subcommand specifications or a coderef.
Each subcommand specification is also a hash(ref) and should contain these keys: url. It can also contain these keys: summary (str, will be retrieved from function metadata if unset), tags (array of str, for categorizing subcommands), log_any_app (bool, whether to load Log::Any::App, default is true, for subcommands that need fast startup you can try turning this off for said subcommands), undo (bool, can be set to 0 to disable transaction for this subcommand; this is only relevant when undo attribute is set to true), pass_cmdline_object (bool, to override pass_cmdline_object attribute on a per-subcommand basis).
summary
log_any_app
undo
pass_cmdline_object
Subcommands can also be a coderef, for dynamic list of subcommands. The coderef will be called as a method with hash arguments. It can be called in two cases. First, if called without argument name (usually when doing --list) it must return a hashref of subcommand specifications. If called with argument name it must return subcommand specification for subcommand with the requested name only.
name
If set, subcommand will always be set to this instead of from the first argument. To use other subcommands, you will have to use --cmd option.
A hash of common options, which are command-line options that are not associated with any subcommand. Each option is itself a specification hash containing these keys:
category (str)
Optional, for grouping options in help/usage message, defaults to Common options.
Common options
getopt (str)
Required, for Getopt::Long specification.
handler (code)
usage (str)
Optional, displayed in usage line in help/usage text.
summary (str)
Optional, displayed in description of the option in help/usage text.
order (int)
Optional, for ordering. Lower number means higher precedence, defaults to 1.
A partial example from the default set by the framework:
{ help => { category => 'Common options', getopt => 'help|h|?', usage => '%1 --help (or -h, -?)', handler => sub { ... }, order => 0, }, format => { category => 'Common options', getopt => 'format=s', summary => 'Choose output format, e.g. json, text', handler => sub { ... }, }, undo => { category => 'Undo options', getopt => 'undo', ... }, ... }
The default contains: help (getopt help|h|?), version (getopt version|v), action (getopt action), format (getopt format=s), format_options (getopt format-options=s). If there are more than one subcommands, this will also be added: list (getopt list|l). If dry-run is supported by function, there will also be: dry_run (getopt dry-run). If undo is turned on, there will also be: undo (getopt undo), redo (getopt redo), history (getopt history), clear_history (getopt clear-history).
help|h|?
version|v
action
format=s
format-options=s
list|l
dry-run
redo
history
clear-history
Sometimes you do not want some options, e.g. to remove format and format_options:
format
format_options
delete $cmd->common_opts->{format}; delete $cmd->common_opts->{format_options}; $cmd->run;
Sometimes you want to rename some command-line options, e.g. to change version to use capital -V instead of -v:
-V
-v
$cmd->common_opts->{version}{getopt} = 'version|V';
Sometimes you want to add subcommands as common options instead. For example:
$cmd->common_opts->{halt} = { category => 'Server options', getopt => 'halt', summary => 'Halt the server', handler => sub { $cmd->{_selected_subcommand} = 'shutdown'; }, };
This will make:
% cmd --halt
equivalent to executing the 'shutdown' subcommand:
% cmd shutdown
If set to 0, instead of exiting with exit(), run() will return the exit code instead.
Whether to load Log::Any::App. Default is yes, or to look at LOG environment variable. For faster startup, you might want to disable this or just use LOG=0 when running your scripts.
Will be passed to Perinci::BashComplete's bash_complete_riap_func_arg. See its documentation for more details.
bash_complete_riap_func_arg
Will be passed to Perinci::BashComplete. See its documentation for more details.
Whether to pass special argument -cmdline containing the Perinci::CmdLine object to function. This can be overriden using the pass_cmdline_object on a per-subcommand basis.
-cmdline
Passing the cmdline object can be useful, e.g. to call run_help(), etc.
Arguments to pass to Perinci::Access. This is useful for passing e.g. HTTP basic authentication to Riap client (Perinci::Access::HTTP::Client):
pa_args => {handler_args => {user=>$USER, password=>$PASS}}
Whether to enable undo/redo functionality. Some things to note if you intend to use undo:
These common command-line options will be recognized
--undo, --redo, --history, --clear-history.
--undo
--redo
--history
--clear-history
Transactions will be used
use_tx=>1 will be passed to Perinci::Access, which will cause it to initialize the transaction manager. Riap requests begin_tx and commit_tx will enclose the call request to function.
use_tx=>1
Called function will need to support transaction and undo
Function which does not meet qualifications will refuse to be called.
Exception is when subcommand is specified with undo=>0, where transaction will not be used for that subcommand. For an example of disabling transaction for some subcommands, see bin/u-trash in the distribution.
undo=>0
bin/u-trash
Where to put undo data. This is actually the transaction manager's data dir.
Create an instance.
The main routine. Its job is to parse command-line options in @ARGV and determine which action method (e.g. run_subcommand(), run_help(), etc) to run. Action method should return an integer containing exit code. If action method returns undef, the next action candidate method will be tried.
After that, exit() will be called with the exit code from the action method (or, if exit attribute is set to false, routine will return with exit code instead).
exit
This section describes how Perinci::CmdLine parses command-line options/arguments into function arguments. Command-line option parsing is implemented by Perinci::Sub::GetArgs::Argv.
For boolean function arguments, use --arg to set arg to true (1), and --noarg to set arg to false (0). A flag argument ([bool => {is=>1}]) only recognizes --arg and not --noarg. For single letter arguments, only -X is recognized, not --X nor --noX.
--arg
arg
--noarg
[bool => {is=>1}]
-X
--X
--noX
For string and number function arguments, use --arg VALUE or --arg=VALUE (or -X VALUE for single letter arguments) to set argument value. Other scalar arguments use the same way, except that some parsing will be done (e.g. for date type, --arg 1343920342 or --arg '2012-07-31' can be used to set a date value, which will be a DateTime object.) (Note that date parsing will be done by Data::Sah and currently not implemented yet.)
--arg VALUE
--arg=VALUE
-X VALUE
For arguments with type array of scalar, a series of --arg VALUE is accepted, a la Getopt::Long:
--tags tag1 --tags tag2 ; # will result in tags => ['tag1', 'tag2']
For other non-scalar arguments, also use --arg VALUE or --arg=VALUE, but VALUE will be attempted to be parsed using JSON, and then YAML. This is convenient for common cases:
--aoa '[[1],[2],[3]]' # parsed as JSON --hash '{a: 1, b: 2}' # parsed as YAML
For explicit JSON parsing, all arguments can also be set via --ARG-json. This can be used to input undefined value in scalars, or setting array value without using repetitive --arg VALUE:
--str-json 'null' # set undef value --ary-json '[1,2,3]' # set array value without doing --ary 1 --ary 2 --ary 3 --ary-json '[]' # set empty array value
Likewise for explicit YAML parsing:
--str-yaml '~' # set undef value --ary-yaml '[a, b]' # set array value without doing --ary a --ary b --ary-yaml '[]' # set empty array value
To do bash completion, first create your script, e.g. myscript, that uses Perinci::CmdLine:
myscript
#!/usr/bin/perl use Perinci::CmdLine; Perinci::CmdLine->new(...)->run;
then execute this in bash (or put it in bash startup files like /etc/bash.bashrc or ~/.bashrc for future sessions):
bash
/etc/bash.bashrc
~/.bashrc
% complete -C myscript myscript; # myscript must be in PATH
For functions that express that they do progress updating (by setting their progress feature to true), Perinci::CmdLine will setup an output, currently either Progress::Any::Output::TermProgressBar if program runs interactively, or Progress::Any::Output::LogAny if program doesn't run interactively.
progress
This module observes the following Rinci metadata property attributes:
Set default output format (if user does not specify via --format command-line option).
This module interprets the following result metadata keys:
XXX should perhaps be defined as standard in Rinci::function.
If set to 1, signify that result is a stream. Result must be a glob, or an object that responds to getline() and eof() (like a Perl IO::Handle object), or an array/tied array. Format must currently be text (streaming YAML might be supported in the future). Items of result will be displayed to output as soon as it is retrieved, and unlike non-streams, it can be infinite.
An example function:
$SPEC{cat_file} = { ... }; sub cat_file { my %args = @_; open my($fh), "<", $args{path} or return [500, "Can't open file: $!"]; [200, "OK", $fh, {is_stream=>1}]; }
another example:
use Tie::Simple; $SPEC{uc_file} = { ... }; sub uc_file { my %args = @_; open my($fh), "<", $args{path} or return [500, "Can't open file: $!"]; my @ary; tie @ary, "Tie::Simple", undef, SHIFT => sub { eof($fh) ? undef : uc(~~<$fh> // "") }, FETCHSIZE => sub { eof($fh) ? 0 : 1 }; [200, "OK", \@ary, {is_stream=>1}]; }
See also Data::Unixish and App::dux which deals with streams.
If you don't want to display function output (for example, function output is a detailed data structure which might not be important for end users), you can set cmdline.display_result result metadata to false. Example:
cmdline.display_result
$SPEC{foo} = { ... }; sub foo { ... [200, "OK", $data, {"cmdline.display_result"=>0}]; }
If you want to filter the result through pager (currently defaults to $ENV{PAGER} or less -FRSX), you can set cmdline.page_result in result metadata to true.
$ENV{PAGER}
less -FRSX
cmdline.page_result
For example:
$SPEC{doc} = { ... }; sub doc { ... [200, "OK", $doc, {"cmdline.page_result"=>1}]; }
Instruct Perinci::CmdLine to use specified pager instead of $ENV{PAGER} or the default less or more.
less
more
Instruct Perinci::CmdLine to use this exit code, instead of using (function status - 300).
PERINCI_CMDLINE_PROGRAM_NAME => STR
Can be used to set CLI program name.
PROGRESS => BOOL
Explicitly turn the progress bar on/off.
PAGER => STR
Like in other programs, can be set to select the pager program (when cmdline.page_result result metadata is active). Can also be set to '' or 0 to explicitly disable paging even though cmd.page_result result metadata is active.
''
0
cmd.page_result
The main difference is that Perinci::CmdLine accesses your code through Riap protocol, not directly. This means that aside from local Perl code, Perinci::CmdLine can also provide CLI for code in remote hosts/languages. For a very rough demo, download and run this PHP Riap::TCP server https://github.com/sharyanto/php-Phinci/blob/master/demo/phi-tcpserve-terbilang.php on your system. After that, try running:
% peri-run riap+tcp://localhost:9090/terbilang --help % peri-run riap+tcp://localhost:9090/terbilang 1234
Everything from help message, calling, argument checking, tab completion works for remote code as well as local Perl code.
See Perinci::Result::Format.
To add/remove/rename common options, see the documentation on common_opts attribute. In this case, you want:
common_opts
delete $cmd->common_opts->{format}; #delete $cmd->common_opts->{format_options}; # you might also want this
or perhaps rename it:
$cmd->common_opts->{output_format} = $cmd->common_opts->{format}; delete $cmd->common_opts->{format};
If you specify 'cmdline_src' to 'stdin' to a 'str' argument, the argument's value will be retrieved from standard input if not specified. Example:
use Perinci::CmdLine; $SPEC{cmd} = { v => 1.1, args => { arg => { schema => 'str*', cmdline_src => 'stdin', }, }, }; sub cmd { my %args = @_; [200, "OK", "arg is '$args{arg}'"]; } Perinci::CmdLine->new(url=>'/main/cmd')->run;
When run from command line:
% cat file.txt This is content of file.txt % cat file.txt | cmd arg is 'This is content of file.txt'
See App::dux for an example on how to accomplish that. Basically in App::dux, you feed an array tied with Tie::Diamond as a function argument. Thus you can get lines from file/STDIN iteratively with each().
This framework is currently non-OO and function-centric. There are already several OO-based command-line frameworks on CPAN.
Perinci, Rinci, Riap.
Other CPAN modules to write command-line applications: App::Cmd, App::Rad, MooseX::Getopt.
Steven Haryanto <stevenharyanto@gmail.com>
This software is copyright (c) 2013 by Steven Haryanto.
This is free software; you can redistribute it and/or modify it under the same terms as the Perl 5 programming language system itself.
None are exported by default, but they are exportable.
To install Perinci::CmdLine, copy and paste the appropriate command in to your terminal.
cpanm
cpanm Perinci::CmdLine
CPAN shell
perl -MCPAN -e shell install Perinci::CmdLine
For more information on module installation, please visit the detailed CPAN module installation guide.