Name
File::DataClass::IO - Better IO syntax
Version
0.7.$Revision: 327 $
Synopsis
use File::DataClass::IO;
# Read the first line of a file and chomp the result
my $line = io( q(path_name) )->chomp->getline;
# Write the line to file set permissions, atomic update and fcntl locking
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
The constructor can be called with these method signatures:
- $io = File::DataClass::IO->new( { name => $pathname, ... } )
-
A hash ref containing a list of key value pairs which are the object's attributes (where name is the pathname)
- $io = File::DataClass::IO->new( $pathname, [ $mode, $perms ] )
-
A list of values which are taken as the pathname, mode and permissions. The pathname can be an array ref, a scalar, or an object that stringifies to a scalar path
- $io = File::DataClass::IO->new( $obj )
-
An object which is a File::DataClass::IO
abs2rel
$path = io( q(relative_path_to_file) )->abs2rel( q(optional_base_path) );
Makes the pathname relative. Returns a path
absolute
$io = io( q(relative_path_to_file) )->absolute( q(optional_base_path) );
Calls "rel2abs" without an optional base path. Returns io object
all
$lines = io( q(path_to_file) )->all;
For a file read all the lines and return them as a single scalar
@entries = io( q(path_to_directory) )->all( $level );
For directories returns a list of IO objects for all files and subdirectories. Excludes "curdir" in File::Spec and "updir" in File::Spec
Takes an optional argument telling how many directories deep to search. The default is 1. Zero (0) means search as deep as possible The default can be changed to zero by calling the "deep" method
The filter method can be used to limit the results
The items returned are sorted by name unless "sort"(0) is used
all_dirs
@entries = io( q(path_to_directory) )->all_dirs( $level );
Like ->all( $level )
but returns only directories
all_files
@entries = io( q(path_to_directory) )->all_files( $level );
Like ->all( $level )
but returns only files
append
io( q(path_to_file) )->append( $line1, $line2, ... );
Opens the file in append mode and calls "print" with the passed args
appendln
io( q(path_to_file) )->appendln( $line, $line2, ... );
Opens the file in append mode and calls "println" with the passed args
assert
$io = 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
io( q(path_to_file) )->assert_dirpath;
Create the given directory if it doesn't already exist
assert_filepath
io( q(path_to_file) )->assert_filepath;
Calls "assert_dirpath" on the directory part of the full pathname
assert_open
$io = 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
$io = io( q(path_to_file) )->atomic;
Implements atomic file updates by writing to a temporary file and then renaming it on closure. This method uses the pattern in the _atomic_infix attribute to compute the temporary pathname
atomic_suffix
Syntatic sugar. See "atomix_infix"
atomic_infix
Defaults to B_* (prefix). The * is replaced by the filename to create a temporary file for atomic updates. If the value does not contain a * then it is appended to the filename instead (suffix). Attribute name _atomic_infix
basename
$dirname = io( q(path_to_file) )->basename( @suffixes );
Returns the File::Basename basename
of the passed path
binary
$io = io( q(path_to_file) )->binary;
Sets binary mode
binmode
$io = io( q(path_to_file) )->binmode( $layer );
Sets binmode to the given layer
block_size
Defaults to 1024. The default block size used by the "read" method
buffer
The internal buffer used by "read" and "write"
_build__dir_pattern
Returns the pattern that will match against the current or parent directory
canonpath
$canonpath = io( '././path_to_file' )->canonpath;
Returns the canonical path for the object
catdir
Create a new IO
directory object by concatenating this objects pathname with the one that is supplied
catfile
Create a new IO
file object by concatenating this objects pathname with the one that is supplied
chmod
$io = $io->chmod( q(0644) );
Changes the permission on the file to the selected value. Permission values can be eithe octal or string
chomp
$io = io( q(path_to_file) )->chomp;
Causes input lines to be chomped when "getline" or "getlines" are called
chown
$io = $io->chown( $uid, $gid );
Changes user and group ownership
clear
$io->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
copy
$dest_obj = $io->copy( $destination_path_or_object );
Copies the file to the destination. The destination can be either a path or and IO object. Returns the destination object
deep
@files = io( 'path_to_root_of_tree' )->deep->all_files
Changes the default level for the "all" methods to zero so that the whole directory tree is searched
delete
Deletes the atomic update temporary file if it exists. Then calls "_close_file"
delete_tmp_files
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
DEMOLISH
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
dirname
$dirname = 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
$io = 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
filter
Takes a subroutine reference that is used by the "all" methods to filter which entries are returned. Called with $_
set to each pathname in turn. It should return true if the entry is wanted
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
- autoclose
-
Defaults to true. Attempts to read past end of file will cause the object to be closed
- 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
io
Subroutine exported by default. Returns a new IO object
is_absolute
Return true if the pathname is absolute
is_dir
$bool = io( q(path_to_file) )->is_dir;
Tests to see if the IO object is a directory
is_executable
$bool = io( q(path_to_file) )->is_executable;
Tests to see if the IO object is executable
is_file
$bool = io( q(path_to_file) )->is_file;
Tests to see if the IO object is a file
is_readable
$bool = io( q(path_to_file) )->is_readable;
Tests to see if the IO object is readable
is_reading
Returns true if this IO object is in one of the read modes
is_writable
$bool = io( q(path_to_file) )->is_writable;
Tests to see if the IO object is writable
length
Returns the length of the internal buffer
lock
$io = 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
mkdir
io( q(path_to_directory) )->mkdir;
Create the specified directory
mkpath
io( q(path_to_directory) )->mkpath;
Create the specified path
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
$io = 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
$pathname = $io->pathname( $pathname );
Sets and returns then name attribute
perms
$io = io( q(path_to_file) )->perms( $perms );
Stores the given permissions on the _perms attribute
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
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
$bytes_read = 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
rel2abs
$path = io( q(relative_path_to_file) )->rel2abs( q(optional_base_path) );
Makes the pathname absolute. Returns a path
relative
Calls "abs2rel" without an optional base path
rmdir
Remove the director
rmtree
Remove the directory tree
seek
Seeks to the selected point in the file
separator
Set the record separator used in calls to getlines and chomp
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
splitdir
Proxy for "splitdir" in File::Spec
splitpath
Proxy for "splitpath" in File::Spec
stat
Returns a hash of the values returned by a "stat" call on the pathname
substitute
$io = io( q(path_to_file) )->substitute( $search, $replace );
Substitutes $search
regular expression for $replace
string on each line of the given file
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 0644 octal. If the file already exists update it's last modified datetime stamp
unlink
Delete the specified file
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
$bytes_written = 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
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
Acknowledgements
- Larry Wall
-
For the Perl programming language
- Ingy döt Net <ingy@cpan.org>
-
For IO::All from which I took the API and some tests
Author
Peter Flanigan, <Support at RoxSoft.co.uk>
License and Copyright
Copyright (c) 2011 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
1 POD Error
The following errors were encountered while parsing the POD:
- Around line 1578:
Non-ASCII character seen before =encoding in 'döt'. Assuming CP1252