NAME
    Pod::WSDL - Creates WSDL documents from (extended) pod

INSTALLATION

To install this module type the following:

   perl Makefile.PL
   make
   make test
   make install

SYNOPSIS
      use Pod::WSDL;

      my $pod = new Pod::WSDL(source => 'My::Server', 
        location => 'http://localhost/My/Server',
        pretty => 1,
        withDocumentation => 1);

      print $pod->WSDL;

DESCRIPTION - How to use Pod::WSDL
  Parsing the pod
    How does Pod::WSDL work? If you instantiate a Pod::WSDL object with the
    name of the module (or the path of the file, or an open filehandle)
    providing the web service like this

      my $pwsdl = new Pod::WSDL(source => 'My::Module', 
            location => 'http://my.services.location/on/the/web');

    Pod::WSDL will try to find "My::Module" in @INC, open the file, parse it
    for WSDL directives and prepare the information for WSDL output. By
    calling

      $pwsdl->WSDL;

    Pod::WSDL will output the WSDL document. That's it.

    When using Pod::WSDL, the parser expects you to do the following:

    * Put the pod directly above the subroutines which the web service's
      client is going to call. There may be whitespace between the pod and
      the sub declaration but nothing else.

    * Use the "=begin"/"=end" respectively the "=for" directives according
      to standard pod: anything between "=begin WSDL" and "=end" will be
      treated as pod. Anything composing a paragraph together with "=for
      WSDL" will be treated as pod.

    Any subroutine not preceeded by WSDL pod will be left unmentioned. Any
    standard pod will be ignored (though, for an exception to this, see the
    section on own complex types below).

    The individual instructions for Pod::WSDL always begin with a keyword,
    like "_RETURN" or "_DOC" or "_FAULT". After this different things may
    follow, according to the specific type of instruction. The instruction
    may take one or more lines - everything up to the next line beginning
    with a keyword or the end of the pod is belonging to the current
    instruction.

  Describing Methods
    How do we use Pod::WSDL? In describing a web service's method we have to
    say something about parameters, return values and faults. In addition
    you might want to add some documentation to these items and to the
    method itself.

   Parameters
    WSDL differentiates between in-, out- and inout-parameters, so we do
    that, too. A different matter is the question, if the client can do this
    too, but now we are talking about possibilities, not actualities.

    The pod string describing a parameter has the structure

      (_IN|_OUT|_INOUT) NAME ($|@)TYPE DESCRIPTION

    like

      _IN foo $string This is a foo

    or

      _INOUT bar @bar An array of bars

    You will easily guess what "_IN", "_OUT" and "_INOUT" stand for so we
    can move on. "NAME" is the name of your parameter. It does not have any
    real function (the order of the parameters being the only important
    thing) but it is nice to have it since in a WSDL document the parameters
    need to have names. So instead of having Pod::WSDL automatically
    generate cryptic names (it cannot do that right now) be nice to the
    client and use some sensible name. The "TYPE" of the parameters can be
    any of the xsd (schema) standard types (see [5]) or a type of your own
    creation. The "$" resp. "@" symbols tell Pod::WSDL and your client if it
    is a scalar or array parameter. Everything following the type up to the
    next instruction is treated as the parameter's documentation. If you
    call the constructor of Pod::WSDL with the argument "withDocumentation
    => 1", it will be added to the WSDL.

   Return Values
    Return values work like parameters but since in WSDL there is provision
    for only one return value (you have (in)out parameters, or can return
    arrays if that isn't enough), you do not need to give them a name.
    Pod::WSDL will automatically call them 'Return' in the WSDL document.
    So, the structure of "_RETURN" instructions is

      _RETURN ($|@)TYPE DESCRIPTION

    as in

      _RETURN $string Returns a string

    The pod for one method may only have one "_RETURN" instruction. If you
    don't specify a "_RETURN" instruction, Pod::WSDL will assume that you
    return void. Of course the perl subroutine still will return something,
    but your web service won't. To make this clear Pod::WSDL generates an
    empty response message for this.

    If you want some method to be a one way operation (see [4], ch. 2.4.1),
    say so by using the instruction "_ONEWAY" in the pod. In this case no
    response message will be generated and a "_RETURN" instruction will be
    ignored.

   Faults
    SOAP faults are usually translated into exceptions in languages like
    Java. If you set up a web service using SOAP::Lite, SOAP will trap your
    dying program and generate a generic fault using the message of "die".
    It is also possible to access SOAP::Lite's SOAP::Fault directly if you
    want more control - but this is not our issue. If you want to use
    custom-made fault messages of your own, define them in "_FAULT"
    instructions, which look like this:

      _FAULT TYPE DESCRIPTION

    An example could be the following:

      _FAULT My::Fault If anything goes wrong

    Since you probably won't return an array of fault objects, you do not
    need to use the "($|@)" tokens. Just say that you return a fault,
    declare it's type and add an optional description.

    As with parameters (but in contrary to "_RETURN" instructions) you can
    declare as many "_FAULT" instructions as you like, providing for
    different exception types your method might throw.

   Method Documentation
    Method documentation is easily explained. It's structure is

      _DOC Here comes my documentation ...

    That's it. Use several lines of documentation if you like. If you
    instantiate the Pod::WSDL object with the parameter "withDocumentation
    => 1", it will be written into the WSDL document.

  Describing Modules - Using Own Complex Types
    Quite often it will be the case that you have to use complex types as
    parameters or return values. One example of this we saw when talking
    about faults: you might want to create custom fault types (exceptions)
    of your own to fullfill special needs in the communication between web
    service and client. But of course you also might simply want to pass a
    complex parameter like a address object containing customer data to your
    application. WSDL provides the means to describe complex types borrowing
    the xsd schema syntax. Pod::WSDL makes use of this by allowing you to
    add WSDL pod to your own types. Assuming you have some own type like

      package My::Type;

      sub new {
        bless {
          foo => 'foo',
          bar => -1
        }, $_[0];
      }

      1;

    simply describe the keys of your blessed hash like this.

      =begin WSDL

        _ATTR foo $string A foo
        _ATTR bar $integer And a bar

      =end WSDL

    Put this pod anywhere within the package My::Type. Pod::WSDL will find
    it (if it is in @INC), parse it and integrate it into the WSDL document.
    The "_ATTR" instruction works exactly as the "_IN", "_OUT" and "_INOUT"
    instructions for methods (see above).

    If you initialize the Pod::WSDL object using "withDocumentation => 1",
    Pod::WSDL will look for standard pod in the module, parse it using
    Pod::Text and put it into the WSDL document.

METHODS
  new
    Instantiates a new Pod::WSDL.

   Parameters
    *   source - Name of the source file, package of the source module or
        file handle on source file for which the WSDL shall be generated.
        This source must contain specialized Pod tags. So, if your source is
        '/some/directory/modules/Foo/Bar.pm' with package declaration
        'Foo::Bar', source may be '/some/directory/modules/Foo/Bar.pm' or
        'Foo::Bar' (in which case '/some/directory/modules' has to be in
        @INC) or an open file handle on the file. Right?

    *   location - Target namespace for the WSDL, usually the full URL of
        your webservice's proxy.

    *   pretty - Pretty print WSDL, if true. Otherwise the WSDL will come
        out in one line. The software generating the client stubs might not
        mind, but a person reading the WSDL will!

    *   withDocumentation - If true, put available documentation in the WSDL
        (see "Pod Syntax" above). For used own complex types ('modules')
        this will be the output of Pod::Text on these modules. The software
        generating the client stubs might give a damn, but a person reading
        the WSDL won't!

  WSDL
    Returns WSDL as string.

   Parameters
    *   pretty - Pretty print WSDL, if true. Otherwise the WSDL will come
        out in one line. The software generating the client stubs might not
        mind, but a person reading the WSDL will!

    *   withDocumentation - If true, put available documentation in the WSDL
        (see "Pod Syntax" above). For used own complex types ('modules')
        this will be the output of Pod::Text on these modules. The software
        generating the client stubs might give a damn, but a person reading
        the WSDL won't!

  addNamespace
    Adds a namespace. Will be taken up in WSDL's definitions element.

   Parameters
    1   URI of the namespace

    2   Declarator of the namespace

EXTERNAL DEPENDENCIES
      Carp
      XML::Writer
      IO::Scalar
      Pod::Text
  
    The test scripts use

      XML::XPath

EXAMPLES
    see the *.t files in the distribution

BUGS
    Please send me any bug reports, I will fix them or mention the bugs here
    :-)

TODO
  Describe Several Signatures for one Method
    Of course, one subroutine declaration might take a lot of different sets
    of parameters. In Java or C++ you would have to have several methods
    with different signatures. In perl you fix this within the method. So
    why not put several WSDL pod blocks above the method so the web
    service's client can handle that.

  Implement a Better Parsing of the pod
    Right know, the pod is found using some rather complex regular
    expressions. This is evil and will certainly fail in some situations.
    So, an issue on top of the fixme list is to switch to regular parsing.
    I'm not sure if I can use Pod::Parser since I need the sub declaration
    outside the pod, too.

  Handle Several Package Declarations in One File
    So far, Pod::WSDL assumes a one to one relation between packages and
    files. If it meets several package declarations in one file, it will
    fail some way or the other. For most uses, one package in one file will
    presumably suffice, but it would be nice to be able to handle the other
    cases, too.

  Handle Array based blessed References
    Array based blessed references used for complex types are something of a
    problem.

  Get Information on Complex Types from Somewhere Else
    If you use complex types for parameters that are not your own (we
    assume, that the module containing the web service always is your own),
    you might not be able to put the WSDL pod into the module files. So why
    not fetch it from somewhere else like a configuration file?

  Integrate Pod::WSDL with SOAP::Lite
    With Axis, you simply call the web service's URL with the parameter
    '?wsdl' and you get the WSDL document. It would be nice to be able to do
    this with SOAP::Lite, too.

  Implement Non RPC Style Messages
    Pod::WSDL writes WSDL documents in encoded RPC style. It should be able
    to generate literal RPC and document styles, too.

REFERENCES
    [1] <http://ws.apache.org/axis/>

    [2] <http://search.cpan.org/~kbrown/SOAP-0.28/>

    [3] <http://search.cpan.org/~byrne/SOAP-Lite-0.65_5/>

    [4] <http://www.w3.org/TR/wsdl.html>

    [5] <http://www.w3.org/TR/xmlschema-2/>

SEE ALSO
      http://ws.apache.org/axis/
      http://search.cpan.org/~kbrown/SOAP-0.28/
      http://search.cpan.org/~byrne/SOAP-Lite-0.65_5/
      http://www.w3.org/TR/wsdl
  
      WSDL::Generator (a different way to do it)
      SOAP::WSDL (the client side)
      SOAP::Clean::WSDL (I have not tried this)
 
AUTHOR
    Tarek Ahmed, <bloerch -the character every email address contains-
    oelbsk.org>

COPYRIGHT AND LICENSE
    Copyright (C) 2010 by Tarek Ahmed

    This library is alpha software and comes with no warranty whatsoever. It
    is free software; you can redistribute it and/or modify it under the
    same terms as Perl itself, either Perl version 5.8.5 or, at your option,
    any later version of Perl 5 you may have available.

