NAME¶
Mail::SpamAssassin::Message - decode, render, and hold an RFC-2822 message
DESCRIPTION¶
This module encapsulates an email message and allows access to the various MIME
message parts and message metadata.
The message structure, after initiating a
parse() cycle, looks like this:
Message object, also top-level node in Message::Node tree
|
+---> Message::Node for other parts in MIME structure
| |---> [ more Message::Node parts ... ]
| [ others ... ]
|
+---> Message::Metadata object to hold metadata
PUBLIC METHODS¶
- new()
- Creates a Mail::SpamAssassin::Message object. Takes a hash reference as a
parameter. The used hash key/value pairs are as follows:
"message" is either undef (which will use STDIN), a scalar - a
string containing an entire message, a reference to such string, an array
reference of the message with one line per array element, or either a file
glob or an IO::File object which holds the entire contents of the message.
Note: The message is expected to generally be in RFC 2822 format, optionally
including an mbox message separator line (the "From " line) as
the first line.
"parse_now" specifies whether or not to create the MIME tree at
object-creation time or later as necessary.
The parse_now option, by default, is set to false (0). This allows
SpamAssassin to not have to generate the tree of
Mail::SpamAssassin::Message::Node objects and their related data if the
tree is not going to be used. This is handy, for instance, when running
"spamassassin -d", which only needs the pristine header and body
which is always handled when the object is created.
"subparse" specifies how many MIME recursion levels should be
parsed. Defaults to 20.
- find_parts()
- Used to search the tree for specific MIME parts. See
Mail::SpamAssassin::Message::Node for more details.
- get_pristine_header()
- Returns pristine headers of the message. If no specific header name is
given as a parameter (case-insensitive), then all headers will be returned
as a scalar, including the blank line at the end of the headers.
If called in an array context, an array will be returned with each specific
header in a different element. In a scalar context, the last specific
header is returned.
ie: If 'Subject' is specified as the header, and there are 2 Subject headers
in a message, the last/bottom one in the message is returned in scalar
context or both are returned in array context.
Btw, returning the last header field (not the first) happens to be
consistent with DKIM signatures, which search for and cover multiple
header fields bottom-up according to the 'h' tag. Let's keep it this way.
Note: the returned header will include the ending newline and any embedded
whitespace folding.
- get_mbox_separator()
- Returns the mbox separator found in the message, or undef if there wasn't
one.
- get_body()
- Returns an array of the pristine message body, one line per array
element.
- get_pristine()
- Returns a scalar of the entire pristine message.
- get_pristine_body()
- Returns a scalar of the pristine message body.
- extract_message_metadata($permsgstatus)
- $str = get_metadata($hdr)
- put_metadata($hdr, $text)
- delete_metadata($hdr)
- $str = get_all_metadata()
- finish_metadata()
- Destroys the metadata for this message. Once a message has been scanned
fully, the metadata is no longer required. Destroying this will free up
some memory.
- finish()
- Clean up an object so that it can be destroyed.
- receive_date()
- Return a time_t value with the received date of the current message, or
current time if received time couldn't be determined.
PARSING METHODS, NON-PUBLIC¶
These methods take a RFC2822-esque formatted message and create a tree with all
of the MIME body parts included. Those parts will be decoded as necessary, and
text/html parts will be rendered into a standard text format, suitable for use
in SpamAssassin.
- parse_body()
- parse_body() passes the body part that was passed in onto the
correct part parser, either _parse_multipart() for multipart/*
parts, or _parse_normal() for everything else. Multipart sections
become the root of sub-trees, while everything else becomes a leaf in the
tree.
For multipart messages, the first call to parse_body() doesn't create
a new sub-tree and just uses the parent node to contain children. All
other calls to parse_body() will cause a new sub-tree root to be
created and children will exist underneath that root. (this is just so the
tree doesn't have a root node which points at the actual root node
...)
- _parse_multipart()
- Generate a root node, and for each child part call parse_body() to
generate the tree.
- _parse_normal()
- Generate a leaf node and add it to the parent.