/ 
Mail-Box-2.022
River stage one • 8 direct dependents • 8 total dependents
/ Mail::Box::Parser

NAME

Mail::Box::Parser - reading and writing messages

CLASS INHERITANCE

Mail::Box::Parser is a Mail::Reporter

Mail::Box::Parser is extended by Mail::Box::Parser::Perl

SYNOPSIS

DESCRIPTION

The Mail::Box::Parser manages the parsing of folders. Usually, you won't need to know anything about this module, except the options which are involved with this code.

There are two implementations of this module planned:

  • Mail::Box::Parser::Perl

    A slower parser which only uses plain Perl. This module is a bit slower, and does less checking and less recovery.

  • Mail::Box::Parser::C

    A fast parser written in C. However, this parser is still under development.

On the moment the C parser comes available, and a C compiler is available on your system, it will be used automatically.

METHODS

Initiation

new OPTIONS

(Class method) Create a parser object which can handle one file. For mbox-like mailboxes, this object can be used to read a whole folder. In case of MH-like mailboxes, each message is contained in a single file, so each message has its own parser object.

OPTION               DEFAULT
file                 undef
filename             <required>
log                  'WARNINGS'
mode                 'r'
trace                'WARNINGS'
file => FILE-HANDLE

Any IO::File or GLOB which can be used to read the data from. In case this option is specified, the filename is informational only.

filename => FILENAME

(Required) The name of the file to be read.

log => LEVEL

See Mail::Reporter::new(log)

mode => OPENMODE

File-open mode, which defaults to 'r', which means `read-only'. See perldoc -f open for possible modes. Only applicable when no file is specified.

trace => LEVEL

See Mail::Reporter::new(trace)

The Parser

defaultParserType [CLASS]

(Class or instance method) Returns the parser to be used to parse all subsequent messages, possibly first setting the parser using the optional argument. Usually, the parser is autodetected; the C-based parser will be used when it can be, and the Perl-based parser will be used otherwise.

The CLASS argument allows you to specify a package name to force a particular parser to be used (such as your own custom parser). You have to use or require the package yourself before calling this method with an argument. The parser must be a sub-class of Mail::Box::Parser.

fileChanged

Returns whether the file which is parsed has changed after the last time takeFileInfo() was called.

filename

Returns the name of the file this parser is working on.

start OPTIONS

Start the parser. The parser is automatically started when the parser is created, however can be stopped (see stop()). During the start, the file to be parsed will be opened.

OPTION               DEFAULT
trust_file           <false>
trust_file => BOOLEAN

When we continue with the parsing of the folder, and the modification-time (on operating-systems which support that) or size changed, the parser will refuse to start, unless this option is true.

stop

Stop the parser, which will include a close of the file. The lock on the folder will not be removed (is not the responsibility of the parser).

takeFileInfo

Capture some data about the file being parsed, to be compared later.

Parsing

bodyAsFile FILEHANDLE [,CHARS [,LINES]]

Try to read one message-body from the file, and immediately write it to the specified file-handle. Optionally, the predicted number of CHARacterS and/or LINES to be read can be supplied. These values may be undef and may be wrong.

The return is a list of three scalars: the location of the body (begin and end) and the number of lines in the body.

bodyAsList [,CHARS [,LINES]]

Try to read one message-body from the file. Optionally, the predicted number of CHARacterS and/or LINES to be read can be supplied. These values may be undef and may be wrong.

The return is a list of scalars, each containing one line (including line terminator), preceded by two integers representing the location in the file where this body started and ended.

bodyAsString [,CHARS [,LINES]]

Try to read one message-body from the file. Optionally, the predicted number of CHARacterS and/or LINES to be read can be supplied. These values may be undef and may be wrong.

The return is a list of three scalars, the location in the file where the body starts, where the body ends, and the string containing the whole body.

bodyDelayed [,CHARS [,LINES]]

Try to read one message-body from the file, but the data is skipped. Optionally, the predicted number of CHARacterS and/or LINES to be skipped can be supplied. These values may be undef and may be wrong.

The return is a list of four scalars: the location of the body (begin and end), the size of the body, and the number of lines in the body. The number of lines may be undef.

filePosition [POSITION]

Returns the location of the next byte to be used in the file which is parsed. When a POSITION is specified, the location in the file is moved to the indicated spot first.

lineSeparator

Returns the character or characters which are used to separate lines in the folder file. This is based on the first line of the file. UNIX systems use a single LF to separate lines. Windows uses a CR and a LF. Mac uses CR.

popSeparator

Remove the last-pushed separator from the list which is maintained by the parser. This will return undef when there is none left.

pushSeparator STRING|REGEXP

Add a boundary line. Separators tell the parser where to stop reading. A famous separator is the From-line, which is used in Mbox-like folders to separate messages. But also parts (attachments) is a message are divided by separators.

The specified STRING describes the start of the separator-line. The REGEXP can specify a more complicated format.

readHeader

Read the whole message-header and return it as list field => value, field => value. Mind that some fields will appear more than once.

The first element will represent the position in the file where the header starts. The follows the list of header field names and bodies.

Examples:

my ($where, @header) = $parser->readHeader;
readSeparator OPTIONS

Read the currently active separator (the last one which was pushed). The line (or undef) is returned. Blank-lines before the separator lines are ignored.

The return are two scalars, where the first gives the location of the separator in the file, and the second the line which is found as separator. A new separator is activated using the pushSeparator() method.

Logging and Tracing

defaultTrace [LEVEL, [LEVEL]

See Mail::Reporter::defaultTrace()

errors

See Mail::Reporter::errors()

log [LEVEL [,STRINGS]]

See Mail::Reporter::log()

report [LEVEL]

See Mail::Reporter::report()

reportAll [LEVEL]

See Mail::Reporter::reportAll()

trace [LEVEL]

See Mail::Reporter::trace()

warnings

See Mail::Reporter::warnings()

Other Methods

AUTOLOAD

See Mail::Reporter::AUTOLOAD()

DESTROY

See Mail::Reporter::DESTROY()

inGlobalDestruction

See Mail::Reporter::inGlobalDestruction()

logPriority LEVEL

See Mail::Reporter::logPriority()

logSettings

See Mail::Reporter::logSettings()

notImplemented

See Mail::Reporter::notImplemented()

SEE ALSO

A good start to read is Mail::Box-Overview. More documentation and a mailinglist are available from the project's website at http://perl.overmeer.net/mailbox/.

AUTHOR

Mark Overmeer (mark@overmeer.net) with the help of many.

VERSION

This code is beta, version 2.022.

Copyright (c) 2001-2002 Mark Overmeer. All rights reserved. This program is free software; you can redistribute it and/or modify it under the same terms as Perl itself.