Workflow::Config - Parse configuration files for the workflow components
This documentation describes version 1.62 of this package
# Reference multiple files my $parser = Workflow::Config->new( 'xml' ); my @config = $parser->parse( 'action', 'workflow_action.xml', 'other_actions.xml' ); # Read in one of the file contents from somewhere else my $xml_contents = read_contents_from_db( 'other_actions.xml' ); my @config = $parser->parse( 'action', 'workflow_action.xml', \$xml_contents ); _ # Reference multiple files of mixed types my @action_config = Workflow::Config->parse_all_files( 'action', 'my_actions.xml', 'your_actions.perl' );
Read in configurations for the various workflow components. Currently the class understands XML (preferred) and serialized Perl data structures as valid configuration file formats. (I tried to use INI files but there was too much deeply nested information. Sorry.)
Runs through each file in @files and processes it according to the valid
@files
If you want to store your configuration in a different format you can create your own parser. All you need to do is:
subclass Workflow::Config
implement the required methods (listed below)
register your parser with Workflow::Config.
For instance, if you wanted to use YAML for configuration files you would do something like:
# just a convention, you can use any namespace you want package Workflow::Config::YAML; use strict; # Requirement 1: Subclass Workflow::Config use base qw( Workflow::Config ); # Requirement 2: Implement required methods sub parse { ... }
The third requirement is registration, which just tells Workflow::Config which parser to use for a particular type. To do this you have two options.
Registration option one
Register yourself in your own class, adding the following call anywhere the end:
# Option 1: Register ourselves by name Workflow::Config->register_factory_type( yaml => 'Workflow::Config::YAML' );
Now you just need to include the configuration class in your workflow invocation script:
use strict; use Workflow::Factory qw( FACTORY ); use Workflow::Config::YAML; # <-- brings in the registration
Registration option two
You can also just explicitly add the registration from your workflow invocation script:
use strict; use Workflow::Factory qw( FACTORY ); use Workflow::Config; # Option 2: explicitly register your configuration parser Workflow::Config->register_factory_type( yaml => 'Workflow::Config::YAML' );
Whichever one you choose you can now parse (in this example) YAML files alongside the built-in parsers for XML and Perl files:
FACTORY->add_config_from_file( workflow => 'workflow.yaml', action => [ 'my_actions.yaml', 'other_actions.xml' ], validator => 'validators.yaml', condition => [ 'my_conditions.yaml', 'other_conditions.xml' ] persister => 'persister.perl', );
Instantiates an object of the correct type -- see Class::Factory for how this is implemented:
# Parser of type 'Workflow::Config::XML' my $xml_parser = Workflow::Config->new( 'xml' ); # Parser of type 'Workflow::Config::Perl my $perl_parser = Workflow::Config->new( 'perl' );
Returns true if $config_type is a valid configuration type, false if not. Valid configuration types are: 'action', 'condition', 'validator', 'workflow'.
$config_type
Returns list of strings representing the valid configuration types.
Returns string representing a valid configuration type, looking up the type parameter in a lookuptable defined in Workflow::Config class.
Parse each item in @items to a hash reference based on the configuration type $config_type which must pass the is_valid_config_type() test. An 'item' is either a filename or a scalar reference with the contents of a file. (You can mix and match as seen in the SYNOPSIS.)
@items
is_valid_config_type()
Should throw an exception if:
You pass an invalid workflow configuration type. Valid workflow configuration types are registered in Workflow::Config and are available from get_valid_config_types(); you can check whether a particular type is valid with is_valid_config_type(). (See above for descriptions.)
get_valid_config_types()
You pass in a file that cannot be read or parsed because of permissions, malformed XML, incorrect Perl data structure, etc. It does not do a validation check (e.g., to ensure that every 'action' within a workflow state has a 'resulting_state' key).
Returns: one hash reference for each member of @items
This gives you an idea of the configuration information in the various workflow pieces:
workflow class $ type $ description $ persister $ initial_state $ observer \@ sub $ class $ state \@ name $ description $ action \@ name $ resulting_state $ condition \@ name $
the 'class', 'type' and 'description' keys are at the top level
'persister' key holds a string declaring the name of a persister as declared in the array of persisters
'initial_state' key holds a string declaring the name of the initial state. by default, this value is 'INIITAL'.
'state' key holds array of one or more 'state' declarations; one of them must be 'INITIAL' (or the value of initial_state, if it's defined)
each 'state' declaration holds 'description' and 'name' keys and multiple 'action' declarations
each 'action' declaration holds 'name' and 'resulting_state' keys and may hold a 'condition' key with one or more named conditions
conditions: type $ condition \@ name $ class $ param \@ name $ value $
array of one or more hashrefs with 'name' and 'class' keys
validators: validator \@ name $ class $ param \@ name $ value $
array of one or more hashrefs with 'name' and 'class' keys, plus possibly one or more 'param' hashrefs each with 'name' and 'value' keys
actions: type $ action \@ name $ class $ description $ field \@ name $ is_required yes|no type $ source_list \@ of $ source_class $ param \@ name $ value $ validator \@ name $ arg \@ value $
array of one or more action hashrefs with 'name', 'class' and 'description' keys
each 'action' may specify a 'type' (default value: 'default'); in case a workflow specifies a 'type', actions specifying the same 'type' will be preferred over actions with the 'default' type when multiple actions by the same name exist.
each 'action' may have zero or more values used to fill it; each value has a 'name', 'description' and 'necessity' ('required' or 'optional')
each 'action' may have any number of 'param' hashrefs, each with 'name' and 'value'
each 'action' may have any number of 'validator' hashrefs, each with a 'name' key and array of 'arg' declarations
persister: name $ # all persister classes class $ # all persister classes use_random yes|no # all persister classes use_uuid yes|no # all persister classes driver $ # DBI persisters dsn $ # DBI persisters user $ # DBI persisters password $ # DBI persisters workflow_table $ # DBI persisters history_table $ # DBI persisters autocommit $ # DBI persisters date_format $ # DBI persisters table $ # DBI/ExtraData persisters data_field $ # DBI/ExtraData persisters context_key $ # DBI/ExtraData persisters path $ # File persisters
'name' key holds a string declaring the name by which workflows may refer to this persister configuration
'class' key names a Perl class name to use when instantiating the persister
'use_random' key holds a string declaring (through 'yes'/'no' value) to use random values for the workflow identifier
'use_uuid' key holds a string declaring (through 'yes'/'no' value) to use UUID (universally unique ID) values for the workflow identifier; UUIDs take preference over random IDs
For documentation of the other keys, please refer to the respective classes.
Copyright (c) 2003-2023 Chris Winters. All rights reserved.
This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself.
Please see the LICENSE
Please see Workflow
To install Workflow, copy and paste the appropriate command in to your terminal.
cpanm
cpanm Workflow
CPAN shell
perl -MCPAN -e shell install Workflow
For more information on module installation, please visit the detailed CPAN module installation guide.