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NAME

Template::Resolver - A powerful, and simple, library for resolving placeholders in templated files

VERSION

version 1.16

DESCRIPTION

This module provides a powerful way to resolve placeholders inside of a templated file. It uses Template::Transformer to interpolate the the placeholder values. The provided template may refer to entity values directly (i.e. ${TEMPLATE{my.entity.value}}) or through transformations (i.e. ${TEMPLATE_perl{property("my.truthy") ? "true" : "false"}}). You may also loop over hash and array entities like this (newlines and indentation included for clarity):

${TEMPLATE<CLUB>:{my.clubs}}$
    {TEMPLATE<MEMBER>:{<CLUB>.members}}
        ${TEMPLATE{<MEMBER>.name}} is a member of the ${TEMPLATE{<CLUB>.club_name}} club.
    ${TEMPLATE<MEMBER>:end}
${TEMPATE<CLUB>:end}

You may access the key when iterating over hashes:

${TEMPLATE<RESOURCE>:{my.resources}}
    Resource, ${TEMPLATE:<RESOURCE.key>} is ${TEMPLATE{<RESOURCE>.deployed_artifact}}
${TEMPLATE<RESOURCE>:end}

You may also access the index when iterating over arrays:

${TEMPLATE<CLUB>:{my.clubs}}
    Club at index ${TEMPLATE<CLUB.ix>} is ${TEMPLATE{<CLUB.name>}}
${TEMPLATE<CLUB>:end}

CONSTRUCTORS

new(\%entity, %options)

Creates a new resolver with properties from \%entity and %options if any. The available options are:

additional_transforms

Additional custom transforms that will be added to the standard transforms. Must be a hashref containing transform name to sub reference mappings. The sub reference(s) will be called as a method(s) with a single parameter containing the contents of the placeholder.

os

The operating system path format used when resolving ${TEMPLATE_os{xxx}} placeholders.

METHODS

resolve(%options)

Will read the template and replace all placeholders prefixed by key. One of the options content, handle, or filename is required. The available options are:

content

A string containing templated content.

filename

The name of a file containing templated content.

handle

A handle to a file containing templated content.

key

The template key, defaults to TEMPLATE.

AUTHOR

Lucas Theisen <lucastheisen@pastdev.com>

COPYRIGHT AND LICENSE

This software is copyright (c) 2015 by Lucas Theisen.

This is free software; you can redistribute it and/or modify it under the same terms as the Perl 5 programming language system itself.

SEE ALSO

Please see those modules/websites for more information related to this module.

SYNOPSIS # Basic example use Template::Resolver; my $resolver = Template::Resolver->new($entity); $resolver->resolve(file => '/path/to/file', key => 'REPLACEME');

# More complete example
use Template::Resolver;

$java_properties_file = <<'EOF';

  # Simple value that will error if not present
  server_port = ${TEMPLATE{app.port}}

  # Simple value with a default (no error if not present)
  context_path = ${TEMPLATE{app.context_path:/myapp}}

  # Get an env var
  http_proxy = ${TEMPLATE_env{HTTP_PROXY}}

  # Translate a cygwin path with error if not present
  module_jar = ${TEMPLATE_os{app.module_addon1}}

  # Translate a cygwin path with default
  module_jar = ${TEMPLATE_os{app.module_addon2:/var/local/lib/mymodule.jar}}

  # Escape some xml (with blank default)
  html_header = ${TEMPLATE_xml_escape{app.header:}}

  # Run some perl
  https_enabled = ${TEMPLATE_perl{ property(app.use_https) ? 'true' : 'false'}}
  https_proxy = ${TEMPLATE_perl{ sprintf( 'https://%s:%d/', $ENV{HTTPS_PROXY_HOST}, $ENV{HTTPS_PROXY_PORT} )}}

  # Custom stuff
  db_user = ${TEMPLATE_customfetch{ 'dbuser' }}

EOF

my $entity = {
    app => {
        port => 80,
        module_addon1 => '/var/local/lib/mymodule.jar',
        use_https => 0,
    }
};

my $resolver = Template::Resolver->new( $entity, additional_transforms => {
    customfetch => sub {
        #Do something here
        return 'mydbuser';
    }
});
my $transformed_result = $resolver->resolve( content => $java_properties_file );