TemplateM - *ML templates processing module

- NAME
- VERSION
- SYNOPSIS
- ABSTRACT
- TERMS

- Scheme
- Template
- Directive
- Structure
- Label

- DESCRIPTION

- SCHEMES
- CONSTRUCTOR
- DEFAULT SCHEME METHODS (BASIC METHODS)

- cast
- cast_loop
- finalize
- cast_if
- html

- GALORE SCHEME METHODS

- stash
- start and finish
- loop
- ifelse
- output
- html

- EXAMPLE
- TEMPLATEM'S AND SSI DIRECTIVES

- ENVIRONMENT
- BUGS
- SEE ALSO
- DIAGNOSTICS
- HISTORY
- TODO
- THANKS
- AUTHOR
- COPYRIGHTS

# NAME

TemplateM - *ML templates processing module

# VERSION

Version 2.23

26 May 2008

# SYNOPSIS

        use TemplateM;
        use TemplateM 3.00;
        use TemplateM 'galore';
        use TemplateM 3.00 'galore';

        $template = new TemplateM(
                -file => 'http://localhost/foo.shtml',
                -utf8 => 1,
            );

        # DEFAULT:

        $template->cast({foo => 'value1', bar => 'value2', ... });
        my %h = ( ... );
        $template->cast(\%h);

        $template->cast_loop ("block_label", {foo => 'value1', bar => 'value2', ... });
        $template->finalize ("block_label);

        $template->cast_if('block_label', $predicate);

        # GALORE:

        my $block = $template->start('block_label');
        $block->loop(foo => 'value1', bar => 'value2', ... );

        $template->stash(foo => 'value1', bar => 'value2', ...);
        $block->stash(baz => 'value1', ... );

        $template->ifelse("ifblock_label", $predicate)
        $block->ifelse("ifblock_label", $predicate)

        $block->output;

        $block->finish;

        $template->output;
        $template->html("Content-type: text/html\n\n");

# ABSTRACT

The TemplateM module means for text templates processing in XML, HTML, TEXT and so on formats. TemplateM is the alternative to most of standard modules, and it can accomplish remote access to template files, has simple syntax, small size and flexibility. Then you use TemplateM, functionality and data are completely separated, this is quality of up-to-date web-projects.

# TERMS

## Scheme

Set of methods prodiving process template's structures.

## Template

File or array of data which represents the set of instructions, directives and tags of markup languages and statistics.

## Directive

Name of structure in a template for substitution. There are a number of directives:

        cgi, val, do, loop, if, endif, else, endelse

## Structure

Structure is the tag or the group of tags in a template which defining a scope of substitution. The structure consist of tag <!-- --> and formatted content:

        DIRECTIVE: LABEL

The structure can be simple or complex. Simple one is like this:

        <!-- cgi: foo -->
        or
        <!-- val: bar -->

Complex structure is the group of simple structures which constitutive a "section"

        <!-- do: foo -->
        ...
            <!-- val: bar -->
        ...
        <!-- loop: foo -->

        even so:

        <!-- if: foo -->
        ...
        <!-- endif: foo -->
        <!-- else: foo -->
        ...
        <!-- endelse: foo -->

## Label

This is identifier of structure. E.g. foo, bar, baz

        <!-- cgi: foo -->

# DESCRIPTION

## SCHEMES

While defining use it can specify 2 accessible schemes - galore or default. It is not obligatory to point at default scheme.

Default scheme is basic and defines using of basic methods:

`cast, cast_if, cast_loop, finalize and html`

Default scheme methods is expedient for small-datasize projects.

Galore scheme is the alternative for base scheme and it defines own set of methods:

`stash, start, loop, finish, ifelse, output and html`

In order to get knowing which of schemes is activated you need to invoke methods either `module()` or `scheme()`

        my $module = $template->module;
        my $module = $template->scheme;

In order to get know real module name of the used scheme it's enough to read property 'module' of $template object

        my $module = $template->{module};

## CONSTRUCTOR

Constructor `new()` is the principal method independent of selected scheme. Almost simple way to use the constructor is:

        my $template = new TemplateM( -template => "blah-blah-blah" );

This invoking takes directive to use simple text as template.

Below is the attribute list of constructor:

asfile

  Asfile flag designates either path or filehandle to file is passed for reading from disk, bypassing the method of remote obtaining of a template.

cache

  Cache is the absolute or relative path to directory for cache files storage. This directory needs to have a permission to read and write files. When cache is missed caching is disabled. Caching on is recommended for faster module operations.

file

  Template filename is the filename, opened filehandler (GLOB) or locations of a template. Supports relative or absolute pathes, and also template file locator. Relative path can forestall with ./ prefix or without it. Absolute path must be forestall with / prefix. Template file locator is the URI formatted string. If the file is missed, it use ``index.shtml' from current directory as default value.

header

  HTTP header uses as value by default before main content template print (method html).

          my $template = new TemplateM( -header => "Content-type: text/html; charset=UTF-8\n\n");
          print $template->html;

login and password

  User Login and user password are data for standard HTTP-authorization. Login and password will be used when the template defined via locator and when remote access is protected by HTTP-authorization of remote server. When user_login is missed the access to remote template file realizes simplified scheme, without basic HTTP-authorization.

method

  Request method points to method of remote HTTP/HTTPS access to template page. Can take values: "GET", "HEAD", "PUT" or "POST". HEAD methods can be used only for headers getting.

onutf8 or utf8

  onutf8 flag turn UTF8 mode for access to a file. The flag allow to get rid of a forced setting utf-8 flag for properties template and work by method Encode::_utf8_on()

template

  HTTP content (template). This attribute has to be defined when template content is not able to get from a file or get it from remote locations. E.g. it has to be defined when a template selects from a database. Defining of this attribute means disabling of precompile result caching!

timeout

  Timeout is the period of cache file keeping in integer seconds. When the value is missed cache file "compiles" once and will be used as template. Positive value has an effect only then template file is dynamic and it changes in time. Previous versions of the module sets value 20 instead 0 by default. It had to set the value -1 for "compilation" disabling. For current version of the module value can be 0 or every positive number. 0 is equivalent -1 of previous versions of the module.

reqcode

  Request code is the pointer to the subroutine must be invoked for HTTP::Request object after creation via method new.

  Sample:

          -reqcode => sub {
              my $req = shift;
              ...
              $req-> ...
              ...
              return 1;
          }

rescode

  Response code is the pointer to the subroutine must be invoked for HTTP::Response after creation via calling $ua->`request($req)`.

  Sample:

          -rescode => sub {
              my $res = shift;
              ...
              $res-> ...
              ...
              return 1;
          }

uacode

  UserAgent code is the pointer to the subroutine must be invoked for LWP::UserAgent after creation via method `new()`.

  Sample:

          -uacode => sub {
              my $ua = shift;
              ...
              $ua-> ...
              ...
              return 1;
          }

uaopts

  UserAgent options is the pointer to the hash containing options for defining parameters of UserAgent object's constructor. (See LWP::UserAgent)

  Example:

          -uaopts => {
              agent                 => "Mozilla/4.0",
              max_redirect          => 10,
              requests_redirectable => ['GET','HEAD','POST'],
              protocols_allowed     => ['http', 'https'], # Required Crypt::SSLeay
              cookie_jar            => new HTTP::Cookies(
                      file     => File::Spec->catfile("/foo/bar/_cookies.dat"),
                      autosave => 1
                  ),
              conn_cache            => new LWP::ConnCache(),
          }

## DEFAULT SCHEME METHODS (BASIC METHODS)

It is enough to define the module without parameters for using of basic methods.

        use TemplateM;

After that only basic metods will be automatically enabled.

### cast

Modification of labels (cgi labels)

        $template->cast({label1=>value1, label2=>value2, ... });

label

  Label - name will be replaced with appropriate value in tag <!-- cgi: label -->

value

  Value - Value, which CGI-script sets. Member of the the label manpage manpage

### cast_loop

Block labels modification (val labels)

        $template->cast_loop (block_label, {label1=>value1, label2=>value2, ... }]);

block_label

  Block label - Block identification name. The name will be inserted in tags <!-- do: block_label --> and <!-- loop: block_label --> - all content between this tags processes like labels, but the tag will be formed as <!-- val: label -->

### finalize

Block finalizing

        $template->finalize(block_label);

Block finalizing uses for not-processed blocks deleting. You need use finalizing every time you use blockes.

### cast_if

        $template->cast_if(ifblock_label, predicate);

Method analyses boolean value of predicate. If value is true, the method prints if-structure content only.

        <!-- if: label -->
            ... blah blah blah ...
        <!-- end_if: label -->

otherwise the method prints else-structure content only.

        <!-- else: label -->
            ... blah blah blah ...
        <!-- end_else: label -->

### html

Template finalizing

        print $template->html(-header=>HTTP_header);
        print $template->html(HTTP_header);
        print $template->html;

The procedure will return formed document after template processing. if header is present as argument it will be added at the beginning of template's return.

## GALORE SCHEME METHODS

It is enough to define the module with parameter 'galore' for using of galore scheme methods.

        use TemplateM 'galore';

### stash

stash (or cast) method is the function of import variables value into template.

        $template->stash(title => 'PI' , pi => 3.1415926);

This example demonstrate how all of <!-- cgi: title --> and <!-- cgi: pi --> structures will be replaced by parameters of stash method invoking.

In contrast to default scheme, in galore scheme stash method process directives <!-- cgi: label --> only with defined labels when invoking, whereas cast method of default scheme precess all of directives <!-- cgi: label --> in template!

### start and finish

Start method defines the beginning of loop, and finish method defines the end. Start method returns reference to the subtemplate object, that is all between do and loop directives.

        <!-- do: block_label -->
            ... blah blah blah ...
                <!-- val: label1 -->
                <!-- val: label2 -->
                <!-- cgi: label -->
            ... blah blah blah ...
        <!-- loop: block_label -->

        my $block = $template->start(block_label);
        ...
        $block->finish;

For acces to val directives it is necessary to use loop method, and for access to cgi directives use stash method.

### loop

The method takes as parameters a hash of arguments or a reference to this hash.

        $block->loop(label1 => 'A', label2 => 'B');
        $block->loop({label1 => 'A', label2 => 'B'});

Stash method also can be invoked in $block object context.

        $block->stash(label => 3.1415926);

### ifelse

        $template->ifelse("ifblock_label", $predicate)
        $block->ifelse("ifblock_label", $predicate)

Method is equal to cast_if method of default scheme. The difference, ifelse method can be processed with $template or $block, whereas cast_if method has deal with $template object.

### output

The method returns result of template processing. Output method has deal with $template and $block object:

        $block->output;
        $template->output;

### html

The method is completely equal to html method of default scheme.

## EXAMPLE

In test.pl file:

        use TemplateM 3.00 'galore';

        my $tpl = new TemplateM(
            -file   => 'test.tpl',
            -asfile => 1,
        );

        $tpl->stash(
            module  => (split(/\=/,"$tpl"))[0],
            version => $tpl->VERSION,
            scheme  => $tpl->scheme()." / ".$tpl->{module},
            date    => scalar(localtime(time())),
        );

        my $row_box = $tpl->start('row');
        foreach my $row ('A'..'F') {
            $row_box->loop({});
            my $col_box = $row_box->start('col');
            foreach my $col (1...6) {
                $col_box->loop( foo  => $row.$col );
                $col_box->cast_if(div=>(
                        ('A'..'F')[$col-1] ne $row
                        &&
                        ('A'..'F')[6-$col] ne $row
                    ));
            }
            $col_box->finish;
        }
        $row_box->finish;

        binmode STDOUT, ':raw';
        print $tpl->output();

In test.tpl file:

        **********************
        *                    *
        *  Simple text file  *
        *                    *
        **********************

        Table
        =====
        <!-- do: row -->
        +-----------------+
        |<!-- do: col --><!-- if: div --><!-- val: foo --><!-- endif: div -->
        <!-- else: div -->  <!-- endelse: div -->|<!-- loop: col --><!-- loop: row -->
        +-----------------+

        Data
        ====

        Module       : <!-- cgi: module -->
        Version      : <!-- cgi: version -->
        Scheme       : <!-- cgi: scheme -->
        Current date : <!-- cgi: date -->

Result:

        **********************
        *                    *
        *  Simple text file  *
        *                    *
        **********************

        Table
        =====

        +-----------------+
        |  |A2|A3|A4|A5|  |
        +-----------------+
        |B1|  |B3|B4|  |B6|
        +-----------------+
        |C1|C2|  |  |C5|C6|
        +-----------------+
        |D1|D2|  |  |D5|D6|
        +-----------------+
        |E1|  |E3|E4|  |E6|
        +-----------------+
        |  |F2|F3|F4|F5|  |
        +-----------------+

        Data
        ====

        Module       : TemplateM
        Version      : 3.00
        Scheme       : galore / GaloreWin32
        Current date : Sat Dec 18 12:37:10 2010

## TEMPLATEM'S AND SSI DIRECTIVES

The module can be used with SSI directives together, like in this shtml-sample:

        <html>
            <!--#include virtual="head.htm"-->
        <body>
            <center><!-- cgi: head --><center>
            <!-- do: BLOCK_P -->
                <p><!-- val: content --></p>
            <!-- loop: BLOCK_P -->
        </body>
        </html>

# ENVIRONMENT

No environment variables are used.

# BUGS

Please report them.

# SEE ALSO

`LWP`, `LWP::UserAgent`, `HTTP::Request`, `HTTP::Response`, `HTTP::Headers`

# DIAGNOSTICS

The usual warnings if it cannot read or write the files involved.

# HISTORY

1.00 Initial release

1.10 Working with cache ability is added

1.11 Inner method's interface had structured

1.21 New time managment for templates caching. You can set how long template file will be cached before renew.

2.00 New abilities

        * Simultaneous templates using errors is eliminated.
        * Alternate interface of using methods is added.
        * Method of conditional representation of template CAST_IF is added.

2.01 Cache-file access errors corrected

2.20 Module structure has rebuilt and changes has done

        * galore scheme added
        * update method deleted and constructor interface changed
        * errors of cachefile compiling was corrected
          (prefix is deleted, CRLF consecution output is corrected)
        * UTF-8 codepage for templates added
        * mod_perl 1.00 and 2.00 support added

2.21 Mass data processing error under MS Windows is corrected

2.22 Files in the distribution package are changed

2.23 File access errors corrected

3.00 Changes:

        * Full UTF8 support added
        * Direct reading of template file from a disk added
        * SSL (HTTPS) support added
        * Error while getting template via LWP::Simple module fixed
        * Ability of use UserAgent, Request and Response objects added (see libwww-perl)

# TODO

        * simultaneous multiple declared do-loop structure blocks processing.

# THANKS

Thanks to Dmitry Klimov for technical translating `http://fla-master.com`.

# AUTHOR

Lepenkov Sergey (Serz Minus), `minus@mail333.com`

# COPYRIGHTS

Copyright (C) 1998-2010 D&D Corporation. All Rights Reserved