my @conf_files = $class->conf_files();

You can also programmatically add a new conf_file this way.

 $class->conf_files('/path/to/new/conf.file', '/path/to/other/conf.file');      #, etc

However, it'd be better to specify your conf file at use time.

 use Mail::Bulkmail::Object 3.00 "/path/to/conf.file";

This also (naturally) works in all subclasses.

 use Mail::Bulkmail 3.00 "/path/to/conf.file";
 use Mail::Bulkmail::Dynamic 3.00 "/path/to/conf/file";

and so on.

Note that adding on via ->conf_files or importing puts onto the FRONT of the @conf_files array, i.e., those conf files are more significant.

So,

 @conf_files = qw(/path/to/file /path/to/file2);

 use Mail::Bulkmail::Object 3.00 "/path/to/file3" "/path/to/file4";

 Mail::Bulkmail::Object->conf_files("/path/to/file5", "/path/to/file6");

 print Mail::Bulkmail::Object->conf_files;
        #prints out /path/to/file5 /path/to/file6 /path/to/file3 /path/to/file4 /path/to/file path/to/file2

Note that you don't *need* conf files, you can still specify all information at construction time, or via mutators, or whatever. But a conf file can make your life a lot easier.

Okay, now we're going to get into some philosophy. First of all, let me state that I *love* Perl's OO implementation. I usually get smacked upside the head when I say that, but I find it really easy to use, work with, manipulate, and so on. And there are things that you can do in Perl's OO that you can't in Java or C++ or the like. Perl, for example, can have *totally* private values that are completely inaccessible (lexicals, natch). private vars in the other languages can be redefined or tweaked or subclassed or otherwise gotten around in some form. Not Perl.

And I obviously just adore Perl anyway. I get funny looks when I tell people that I like perl so much because it works the way I think. That bothers people for some reason.

Anyway, as much as I like how it works, I don't like the fact that there's no consistent object type. An object is, of course, a blessed ((thingie)) (scalar, array, code, hash, etc) reference. And there are merits to using any of those things, depending upon the situation. Hashes are easy to work with and most similar to traditional objects.

 $object->{$attribute} = $value;

And whatnot. Arrays are much faster (typically 33% in tests I've done), but they suck to work with.

 $object->[15] = $value;        #the hell is '15'?

 (
  by the way, you can make this easier with variables defined to return the value, i.e.
  $object->[$attribute] = $value;       #assuming $attribute == 15
 )

Scalars are speciality and coderefs are left to the magicians. Don't get me wrong, coderefs as objects are nifty, but they can be tricky to work with.

So, I wanted a consistent interface. I'm not going to claim credit for this idea, since I think I originally read it in Object Oriented Programming in Perl (Damien's book). In fact, I think the error reporting method I use was also originally detailed in there. Anyway, I liked it a lot and decided I'd implement my own version of it.

Basically, attributes are accessed and mutated via methods.

 $object->attribute($value);

For all attributes. This way, the internal object can be whatever you'd like. I used to use mainly arrays for the speed boost, but lately I use hashes a lot because of the ease of dumping and reading the structure for debugging purposes. But, with this consistent interface of using methods to wrapper the attributes, I can change the implementation of the object (scalar, array, hash, code, whatever) up in this module and *nothing* else needs to change.

Say you implemented a giant system in OO perl. And you chose hashrefs as your ``object''. But then you needed a big speed boost later, which you could easily get by going to arrays. You'd have to go through your code and change all instances of $object->{$attribute} to $object->[15] or whatever. That's an awful lot of work.

With everything wrappered up this way, changes can be made in the super object class and then automagically populate out everywhere with no code changes. Spiffy stuff.

There are some disadvantages, there is a little more overhead for doing the additional method call, but it's usually negligible. And you can't do nice things like:

 $object->{$attribute}++;
 you'd have to do
 $object->attribute($object->attribute + 1);

Which is annoying. But I think it's offset by the consistent interface regardless of what your underlying object is.

Enough with the philosophy, though. You need to know how this works.

It's easy enough:

 package Some::Class;

 Some::Class->add_attr('foo');

Now your Some::Class objects have a foo attribute, which can be accessed as above. If called with a value, it's the mutator which sets the attribute to the new value and returns the new value. If called without one, it's the accessor which returns the value.

 my $obj = Some::Class->new();
 $obj->foo('bar');
 print $obj->foo();                     #prints bar
 print $obj->foo('boo');        #prints boo
 print $obj->foo();                     #prints boo

add_attr calls should only be in your module. Never in your program. And they really should be defined up at the top.

Internally, an add_attr call creates a function inside your package of the name of the attribute which reflects through to the internal _accessor method which handles the mutating and accessing.

There is another syntax for add_attr, to define a different internal accessor:

 Some::Class->add_attr(['foo', 'other_accessor']);

This creates method called 'foo' which talks to a separate accessor, in this case ``other_accessor'' instead of going to _accessor. This is useful if you want to create a validating method on your attribute.

Additionally, it creates a normal method going to _accessor called '_foo', which is assumed to be the internal attribute slot your other accessor with use. In generall, for a given ``attribute'', ``_attribute'' will be created for internal use.

``other_accessor'' will get the object as the first arg (as always) and the name of the internal method as the second.

Example:

 Some::Class->add_attr(['foo', 'other_accessor']);

 $obj->foo('bee');

 sub other_accessor {
        my $self        = shift;
        my $method      = shift;        # "_foo", in this example

        if (@_){
                my $val = shift;        # "bee", in this example
                if ($val == 7){
                        return $self->$method($val);
                }
                else {
                        return $self->error("Cannot store value...foo must be 7!");
                };
        }
        else {
                return $self->$method();
        };
 };

And, finally, you can also pass in additional arguments as static args if desired.

 Some::Class->add_attr(['foo', 'other_accessor'], 'bar');

 $obj->foo('bee');

 sub other_accessor {
        my $self        = shift;
        my $method      = shift;
        my $static      = shift;        #'bar' in our example

        my $value       = shift;        #'bee' in our example
        .
        .
        .
 };

 All easy enough. Refer to any subclasses of this class for further examples.

 Some::Class->add_attr('foo');                  #object attribute foo
 Some::Class->add_class_attr('bar'):    #class attribute bar

 print $obj->foo();
 print Some::Class->bar();

Behaves the same as an object method added with add_attr, mutating with a value, accessing without one. Note that add_class_attr does not have the capability for additional internal methods or static values. If you want those on a class method, you'll have to wrapper the class attribute yourself on a per case basis.

Note that you can access class attributes via an object (as expected), but it's frowned upon since it may be confusing.

class attributes are automatically initialized to any values in the conf file upon adding, if present.

add_trickle_class_attr behaves the same as add_class_attr with the addition that it will trickle the attribute down into any class as it is called. This is useful for subclasses.

Watch:

 package SuperClass;

 SuperClass->add_class_attr('foo');
 SuperClass->foo('bar');

 package SubClass;
 @ISA = qw(SuperClass);

 print SubClass->foo();                 #prints bar
 print SuperClass->foo();               #prints bar

 print SuperClass->foo('baz');  #prints baz
 print SubClass->foo();                 #prints baz

 print SubClass->foo('dee');    #prints dee
 print SuperClass->foo();               #prints dee

See? The attribute is still stored in the super class, so changing it in a subclass changes it in the super class as well. Usually, this behavior is fine, but sometimes you don't want that to happen. That's where add_trickle_class_attr comes in. Its first call will snag the value from the SuperClass, but then it will have its own attribute that's separate.

Again, watch:

 package SuperClass;

 SuperClass->add_trickle_class_attr('foo');
 SuperClass->foo('bar');

 package SubClass;
 @ISA = qw(SuperClass);

 print SubClass->foo();                 #prints bar
 print SuperClass->foo();               #prints bar

 print SuperClass->foo('baz');  #prints baz
 print SubClass->foo();                 #prints bar

 print SubClass->foo('dee');    #prints dee
 print SuperClass->foo();               #prints baz

This is useful if you have an attribute that should be unique to a class and all subclasses. These are equivalent:

 package SuperClass;
 SuperClass->add_class_attr('foo');

 package SubClass
 SubClass->add_class_attr('foo');

 and

 package SuperClass;
 SuperClass->add_trickle_class_attr('foo');

You'll usually just use add_class_attr. Only use trickle_class_attr if you know you need to, since you rarely would. There is a *slight* bit of additional processing required for trickled accessors.

trickled class attributes are automatically initialized to any values in the conf file upon adding, if present.

If a method fails, it is expected to return undef (or an empty list) and set error.

example:

 sub someMethod {
        my $self = shift;
        my $value = shift;

        if ($value > 10){
                return 1;               #success
        }
        else {
                return $self->error("Values must be greater than 10");
        };
 };

 print $obj->errcode;

Both objects and classes have errcode methods.

 my $obj = Some::Class->new() || die Some::Class->errcode();
 $obj->foo() || die $obj->errcode();

Where possible, the pod will note errors that a method is known to be able to return. Please note that this will never be an all inclusive list of all error codes that may possibly ever be returned by this method. Only error codes generated by a particular method will be listed.

 $bulk->error . ": " . $bulk->errcode;

Nothing more.

 $attribute = $obj->foo() || return $self->error($obj->errvals);

You can also pass in a list of conf files to read, in most to least significant order, same as the @conf_files array.

 my $conf = Mail::Bulkmail::Object->read_conf_file();
 or
 my $conf = Mail::Bulkmail::Object->read_conf_file('/other/conf.file');

If you pass in a list of conf files, then the internal @conf_files array is bypassed.

$conf is a hashref of hashrefs. the main keys are the package names, the values are the hashes of the values for that object.

Example:

 #conf file
 define package Mail::Bulkmail

 use_envelope = 1
 Trusting @= duplicates

 define package Mail::Bulkmail::Server

 Smtp = your.smtp.com
 Port = 25

 $conf = {
        'Mail::Bulkmail' => {
                'use_envelope' => 1,
                'Trusting' => ['duplicates']
        },
        'Mail::Bulkmail::Server' => {
                'Smtp' => 'your.smtp.com',
                'Port' => 25
        }
 };

read_conf_file is called at object initialization. Any defaults for your object are read in at this time. You'll rarely need to read the conf file yourself, since at object creation it is read and parsed and the values passed on.

Be sure to read up on the conf file structure, below

The conf file is only re-read if it has been modified since the last time it was read.

this method is known to be able to return MBO002 - Invalid conf file

 my $handle = Mail::Bulkmail->gen_handle();
 open ($handle, "/path/to/my/list");

 my $bulk = Mail::Bulkmail->new(
        'LIST' => $handle
 );

You never need to use gen_handle if you don't want to. It's used extensively internally, though.

 my $obj = Class->new() || die Class->error();

Ta da! You have an object. Any attributes specified in the conf file will be loaded into your object. So if your conf file defines 'foo' as 'bar', then $obj->foo will now equal 'bar'.

If you'd like, you can also pass in method/value pairs to the constructor.

 my $obj = Class->new(
        'attribute' => '17',
        'foo'           => 'baz',
        'method'        => '88'
 ) || die Class->error();

This is (roughly) the same as:

 my $obj = Class->new() || die Class->error();

 $obj->attribute(17) || die $obj->error();
 $obj->foo('baz') || die $obj->error();
 $obj->method(88) || die $obj->error();

Any accessors or methods you'd like may be passed to the constructor. Any unknown pairs will be silently ignored. If you pass a method/value pair to the constructor, it will override any equivalent method/value pair in the conf file.

Additionally, if you need to set up values in your object, this is the place to do it. Note that setting default values should probably be done in the conf file, but if you need to populate a data structure into a method, do it here.

 package SubClass;
 @ISA = qw(SuperClass);

 sub new {
        return shift->new(
                'servers'               => [],
                'connections'   => {},
                @_
        );
 };

This will cause your SubClass to use the normal constructor, but get default values of the empty data structures specified.

Simply, it iterates through the conf file and mutates any of your object attributes to the value specified in the conf file. It then iterates through the hash you passed to ->new() and does the same thing, overriding any conf values, if necessary.

init is smart enough to use all super class values defined in the conf file, in hierarchy order. So if your conf file contains:

 define package SuperClass

 foo = 'bar'

And you're creating a new SubClass object, then it will get the default of foo = 'bar' as in the conf file, despite the fact that it was not defined for your own package. Naturally, the more significant definition is used.

 define package SuperClass

 foo = 'bar'

 define package SubClass

 foo = 'baz'

SuperClass objects will default foo to 'bar', SubClass objects will default foo to 'baz'

this method is known to be able to return

 MBO003 - could not initialize value to conf value
 MBO004 - could not initialize value to constructor value
 MBO006 - odd number of elements in hash assignment

Note that once a path is looked up for a class, it is cached. So if you dynamically change @ISA, it won't be reflected in the return of isa_path. Obviously, dynamically changing @ISA is frowned upon as a result.

 $obj->getNextLine(\*FOO);

will return the next line off of FOO;

 $obj->getNextLine(\@foo);

will shift the next line off of @foo and return it.

 $obj->getNextLine(\&foo);

will call foo($obj) and return whatever the function returns.

Note that your bulkmail object is the first argument passed to your function. It's not called as a method, but the object is still the first argument passed.

This is mainly used with attribues going through _file_accessor.

 package SomeClass;

 SomeClass->add_attr(['FOO', '_file_accessor'], "<");
 my $obj = SomeClass->new(
        FOO => \&foo
 ) || die SomeClass->error();

 my $val = $obj->getNextLine($obj->FOO);

logToFile is called on either a filehandleref, an arrayref, or a coderef

 $obj->logToFile(\*FOO, "bar");

will append a new line to FOO, ``bar''

 $obj->logToFile(\@foo, "bar");

will push the value ``bar'' onto the end of @foo

 $obj->logToFile(\&foo, "bar");

will call foo($obj, ``bar'')

Note that your bulkmail object is the first argument passed to your function. It's not called as a method, but the object is still the first argument passed.

This is mainly used with attribues going through _file_accessor.

 package SomeClass;

 SomeClass->add_attr(['FOO', '_file_accessor'], ">>");
 my $obj = SomeClass->new(
        FOO => \&foo
 ) || die SomeClass->error();

 my $val = $obj->logToFile($obj->FOO, "valid address);

Internally, logToFile calls convert_to_scalar on the value it is called with.

This method is known to be able to return:

 MBO005 - cannot log to file

Mail::Bulkmail::Object's convert_to_scalar method will only handle scalars, it will dereference scalarrefs, or return scalar values. This method will also strip out any carriage returns or newlines within the scalar before returning it. If passed by reference, your original variable will not be modified.

This is useful to subclass if you ever want to log values other than simple scalars

ERRFILE may be either a coderef, globref, arrayref, or string literal.

If a string literal, then Mail::Bulkmail::Object will attempt to open that file (in append mode) as your log:

 $bulk->ERRFILE("/path/to/my/error.file");

If a globref, it is assumed to be an open filehandle in append mode:

 open (E, ">>/path/to/my/error.file");
 $bulk->ERRFILE(\*E);

if a coderef, it is assumed to be a function to call with the address as an argument:

 sub E { print "ERROR : ", shift, "\n"};        #or whatever your code is
 $bulk->ERRFILE(\&E);

if an arrayref, then bad addresses will be pushed on to the end of it

 $bulk->ERRFILE(\@errors);

Use whichever item is most convenient, and Mail::Bulkmail::Object will take it from there.

It is recommended you turn on ERRFILE in a debugging envrionment, and leave it off in production. You probably shouldn't be getting errors in a production environment, but there may be internal errors that you're not even aware of, so you'll end up filling up that file. And there's the slight additional overhead.

Keep it on in production if you know what you're doing, off otherwise.