/ 
CatalystX-Usul-0.3.625
/ CatalystX::Usul::File::IO

Name

CatalystX::Usul::File::IO - Better IO syntax

Version

0.3.$Revision: 576 $

Synopsis

use MyExceptionClass;
use CatalystX::Usul::File::IO;

sub io {
   my ($self, @rest) = @_;
   my $io = CatalystX::Usul::File::IO->new( @rest );

   $io->exception_class( q(MyExceptionClass) );
   return $io;
}

# Read the first line of a file and chomp the result
my $line = $self->io( q(path_name) )->chomp->getline;

# Write the line to file set permissions, atomic update and fcntl locking
$self->io( q(path_name), q(w), q(0644) )->atomic->lock->print( $line );

Description

This is a simplified re-write of IO::All with additional functionality from IO::AtomicFile. Provides the same minimalist API but without the heavy OO overloading. Only has methods for files and directories

Subroutines/Methods

If any errors occur the "throw" method in the exception_class is called. If that is not defined the module throws an Exception::Class of its own

Methods beginning with an _ (underscore) are deemed private and should not be called from outside this package

new

my $io = CatalystX::Usul::File::IO->new( $pathname, [ $mode, $perms ] );

Called with either a single hash ref containing a list of key value pairs which are the object's attributes (where name is the pathname) or a list of values which are taken as the pathname, mode and permissions. Returns the value from the call to "_init" which it makes without any options

absolute

my $io = $self->io( q(path_to_file) )->absolute;

Makes the pathname absolute

all

my $lines = $self->io( q(path_to_file) )->all;

Read all the lines from the file. Returns them as a single scalar

append

$self->io( q(path_to_file) )->append( $line1, $line2, ... );

Opens the file in append mode and calls "print" with the passed args

appendln

$self->io( q(path_to_file) )->appendln( $line, $line2, ... );

Opens the file in append mode and calls "println" with the passed args

assert

my $io = $self->io( q(path_to_file) )->assert;

Sets the private attribute _assert to true. Causes the open methods to create the path to the directory before the file/directory is opened

assert_dirpath

$self->io( q(path_to_file) )->assert_dirpath;

Create the given directory if it doesn't already exist

assert_filepath

$self->io( q(path_to_file) )->assert_filepath;

Calls "assert_dirpath" on the directory part of the full pathname

assert_open

my $io = $self->io( q(path_to_file) )->assert_open( $mode, $perms );

Calls "file" to default the type if its not already set and then calls "open" passing in the optional arguments

atomic

my $io = $self->io( q(path_to_file) )->atomic;

Implements atomic file updates by writing to a temporary file and then renaming it on closure. This method stores the temporary pathname in the _atomic attribute

basename

$dirname = $self->io( q(path_to_file) )->basename( @suffixes );

Returns the File::Basename basename of the passed path

binary

my $io = $self->io( q(path_to_file) )->binary;

Sets binary mode

binmode

my $io = $self->io( q(path_to_file) )->binmode( $layer );

Sets binmode to the given layer

buffer

The internal buffer used by "read" and "write"

chomp

my $io = $self->io( q(path_to_file) )->chomp;

Causes input lines to be chomped when "getline" or "getlines" are called

clear

Set the contents of the internal buffer to the null string

close

$io->close;

Close the file or directory handle depending on type

_close_dir

Closes the open directory handle.

_close_file

If the temporary atomic file exists, renames it to the original filename. Unlocks the file if it was locked. Closes the file handle

delete

Deletes the atomic update temporary file if it exists. Then calls "_close_file"

delete_tmp_files

$self->io( $tempdir )->delete_tmp_files( $template );

Delete temporary files for this process (temporary file names include the process id). Temporary files are stored in the $tempdir. Can override the template filename pattern if required

DESTROY

If this is an atomic file update calls the "delete" method. If the object is still open it calls the "close" method

dir

Initialises the current object as a directory

dir_pattern

Returns the pattern that will match against the current or parent directory

dirname

$dirname = $self->io( q(path_to_file) )->dirname;

Returns the File::Basename dirname of the passed path

empty

Returns true if the pathname exists and is zero bytes in size

encoding

my $io = $self->io( q(path_to_file) )->encoding( $encoding );

Apply the given encoding to the open file handle and store it on the _encoding attribute

error_check

Tests to see if the open file handle is showing an error and if it is it "throw"s an eIOError

exists

Returns true if the pathname exists

file

Initializes the current object as a file

filename

Returns the filename part of pathname

filepath

Returns the directory part of pathname

getline

Asserts the file open for reading. Get one line from the file handle. Chomp the line if the _chomp attribute is true. Check for errors. Close the file if the autoclose attribute is true and end of file has been read past

getlines

Like "getline" but calls "getlines" on the file handle and returns an array of lines

_init

Sets default values for some attributes, takes two optional arguments; type and name

atomic_pref

Defaults to B_. It is prepended to the filename to create a temporary file for atomic updates

autoclose

Defaults to true. Attempts to read past end of file will cause the object to be closed

block_size

Defaults to 1024. The default block size used by the "read" method

exception_class

Defaults to undef. Can be set to the name of an class that provides the "throw" method

io_handle

Defaults to undef. This is set when the object is actually opened

is_open

Defaults to false. Set to true when the object is opened

name

Defaults to undef. This must be set in the call to the constructor or soon after

type

Defaults to false. Set by the "dir" and "file" methods to dir and file respectively. The "dir" method is called by the "next" method. The "file" method is called by the "assert_open" method if the type attribute is false

is_absolute

Return true if the pathname is absolute

is_dir

my $bool = $self->io( q(path_to_file) )->is_dir;

Tests to see if the IO object is a directory

is_file

my $bool = $self->io( q(path_to_file) )->is_file;

Tests to see if the IO object is a file

length

Returns the length of the internal buffer

lock

my $io = $self->io( q(path_to_file) )->lock;

Causes "_open_file" to set a shared flock if its a read an exclusive flock for any other mode

next

Calls "dir" if the type is not already set. Asserts the directory open for reading and then calls "read_dir" to get the first/next entry. It returns an IO object for that entry

open

my $io = $self->io( q(path_to_file) )->open( $mode, $perms );

Calls either "_open_dir" or "_open_file" depending on type. You do not usually need to call this method directly. It is called as required by "assert_open"

_open_dir

If the _assert attribute is true calls "assert_dirpath" to create the directory path if it does not exist. Opens the directory and stores the handle on the io_handle attribute

_open_file

Opens the pathname with the given mode and permissions. Calls "assert_filepath" if assert is true. Mode defaults to the mode attribute value which defaults to r. Permissions defaults to the _perms attribute value. Throws eCannotOpen on error. If the open succeeds "set_lock" and "set_binmode" are called

pathname

my $pathname = $io->pathname( $pathname );

Sets and returns then name attribute

perms

my $io = $self->io( q(path_to_file) )->perms( $perms );

Stores the given permissions on the _perms attribute

print

Asserts that the file is open for writing and then prints passed list of args to the open file handle. Throws ePrintError if the print statement fails

println

$self->io( q(path_to_file) )->println( $line1, $line2, ... );

Calls "print" appending a newline to each of the passed list args that doesn't already have one

read

my $bytes_read = $self->io( q(path_to_file) )->read( $buffer, $length );

Asserts that the pathname is open for reading then calls "read" on the open file handle. If called with args then these are passed to the "read". If called with no args then the internal buffer is used instead. Returns the number of bytes read

read_dir

Asserts that the file is open for reading. If called in an array context returns a list of all the entries in the directory. If called in a scalar context returns the first/next entry in the directory

set_binmode

Sets the currently selected binmode on the open file handle

set_lock

Calls "flock" on the open file handle

slurp

In a scalar context calls "all" and returns its value. In an array context returns the list created by splitting the scalar return value on the system record separator. Will chomp each line if required

stat

Returns a hash of the values returned by a "stat" call on the pathname

tempfile

Create a randomly named temporary file in the name directory. The file name is prefixed with the creating processes id and the temporary directory defaults to /tmp

throw

Exposes the throw method in the class exception class

touch

Create a zero length file if one does not already exist with given file system permissions which default to 0664 octal. If the file already exists update it's last modified datetime stamp

unlock

Calls flock on the open file handle with the LOCK_UN option to release the Fcntl lock if one was set. Called by the "file_close" method

utf8

Sets the current encoding to utf8

write

my $bytes_written = $self->io( q(pathname) )->write( $buffer, $length );

Asserts that the file is open for writing then write the $length bytes from $buffer. Checks for errors and returns the number of bytes written. If $buffer and $length are omitted the internal buffer is used. In this case the buffer contents are nulled out after the write

Diagnostics

None

Configuration and Environment

None

Dependencies

Class::Accessor::Fast
Exception::Class

Incompatibilities

There are no known incompatibilities in this module

Bugs and Limitations

There are no known bugs in this module. Please report problems to the address below. Patches are welcome

Author

Peter Flanigan, <Support at RoxSoft.co.uk>

License and Copyright

Copyright (c) 2008 Peter Flanigan. All rights reserved

This program is free software; you can redistribute it and/or modify it under the same terms as Perl itself. See perlartistic

This program is distributed in the hope that it will be useful, but WITHOUT WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE