### Get the bodyhandle of a MIME::Entity object: $body = $entity->bodyhandle; ### Create a body which stores data in a disk file: $body = new MIME::Body::File "/path/to/file"; ### Create a body which stores data in an in-core array: $body = new MIME::Body::InCore \@strings;
### Write data to the body: $IO = $body->open("w") || die "open body: $!"; $IO->print($message); $IO->close || die "close I/O handle: $!"; ### Read data from the body (in this case, line by line): $IO = $body->open("r") || die "open body: $!"; while (defined($_ = $IO->getline)) { ### do stuff } $IO->close || die "close I/O handle: $!";
### Dump the ENCODED body data to a filehandle: $body->print(\*STDOUT); ### Slurp all the UNENCODED data in, and put it in a scalar: $string = $body->as_string; ### Slurp all the UNENCODED data in, and put it in an array of lines: @lines = $body->as_lines;
### Where's the data? if (defined($body->path)) { ### data is on disk: print "data is stored externally, in ", $body->path; } else { ### data is in core: print "data is already in core, and is...\n", $body->as_string; } ### Get rid of anything on disk: $body->purge;
This class is an attempt to define a common interface for objects which contain message data, regardless of how the data is physically stored. The lifespan of a ``body'' object usually looks like this:
You can write your own subclasses, as long as they follow the interface described below. Implementers of subclasses should assume that steps 2 and 3 may be repeated any number of times, and in different orders (e.g., 1-2-2-3-2-3-3-3-3-3-2-4).
In any case, once a MIME::Body has been created, you ask to open it for reading or writing, which gets you an ``i/o handle'': you then use the same mechanisms for reading from or writing to that handle, no matter what class it is.
Beware: unless you know for certain what kind of body you have, you should not assume that the body has an underlying filehandle.
Note: the default method gets the data via repeated getline() calls; your subclass might wish to override this.
Note: the default method uses print(), which gets the data via repeated read() calls; your subclass might wish to override this.
Beware: external data in bodyhandles is not copied to new files! Changing the data in one body's data file, or purging that body, will affect its duplicate. Bodies with in-core data probably need not worry.
This method is expected to return an ``I/O handle'' object on success, and undef on error. An I/O handle can be any object that supports a small set of standard methods for reading/writing data. See the IO::Handle class for an example.
Where appropriate, the path should be a simple string, like a filename. With argument, sets the PATH, which should be undef if there is none.
Body Stores body When open()ed, class: data in: returns: -------------------------------------------------------- MIME::Body::File disk file IO::Handle MIME::Body::Scalar scalar IO::Handle MIME::Body::InCore scalar array IO::Handle
$body = new MIME::Body::File "/path/to/file";
In this case, the "path()" method would return the given path, so you could say:
if (defined($body->path)) { open BODY, $body->path or die "open: $!"; while (<BODY>) { ### do stuff } close BODY; }
But you're best off not doing this.
$body = new MIME::Body::Scalar \$string;
A single scalar argument sets the body to that value, exactly as though you'd opened for the body for writing, written the value, and closed the body again:
$body = new MIME::Body::Scalar "Line 1\nLine 2\nLine 3";
A single array reference sets the body to the result of joining all the elements of that array together:
$body = new MIME::Body::Scalar ["Line 1\n", "Line 2\n", "Line 3"];
$body = new MIME::Body::InCore \$string; $body = new MIME::Body::InCore $string; $body = new MIME::Body::InCore \@stringarray
A simple scalar argument sets the body to that value, exactly as though you'd opened for the body for writing, written the value, and closed the body again:
$body = new MIME::Body::InCore "Line 1\nLine 2\nLine 3";
A single array reference sets the body to the concatenation of all scalars that it holds:
$body = new MIME::Body::InCore ["Line 1\n", "Line 2\n", "Line 3"];
Your ``body'' class must inherit from MIME::Body (or some subclass of it), and it must either provide (or inherit the default for) the following methods...
The default inherited method should suffice for all these:
new binmode [ONOFF] path
The default inherited method may suffice for these, but perhaps there's a better implementation for your subclass.
init ARGS... as_lines as_string dup print purge
The default inherited method will probably not suffice for these:
open
### Get body handle from this MIME message, and read its data: $body = $entity->bodyhandle; $IO = $body->open("r"); while (defined($_ = $IO->getline)) { print STDOUT $_; } $IO->close;
...without requiring that they know anything more about how the $body object is actually storing its data (disk file, scalar variable, array variable, or whatever).
Storing the body of each MIME message in a persistently-open IO::Handle was a possibility, but it seemed like a bad idea, considering that a single multipart MIME message could easily suck up all the available file descriptors on some systems. This risk increases if the user application is processing more than one MIME entity at a time.
All rights reserved. This program is free software; you can redistribute it and/or modify it under the same terms as Perl itself.
Thanks to Achim Bohnet for suggesting that MIME::Parser not be restricted to the use of FileHandles.
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