egroupware/phpgwapi/doc/vfs/vfs.lyx
2001-06-23 08:30:14 +00:00

1968 lines
38 KiB
Plaintext

#LyX 1.1 created this file. For more info see http://www.lyx.org/
\lyxformat 2.16
\textclass linuxdoc
\language default
\inputencoding latin1
\fontscheme default
\graphics default
\paperfontsize default
\spacing single
\papersize Default
\paperpackage a4
\use_geometry 0
\use_amsmath 0
\paperorientation portrait
\secnumdepth 5
\tocdepth 5
\paragraph_separation indent
\defskip medskip
\quotes_language english
\quotes_times 2
\papercolumns 1
\papersides 1
\paperpagestyle default
\layout Title
\added_space_top vfill \added_space_bottom vfill
phpgwapi - VFS Class
\layout Author
Jason Wies
\layout Date
June 2001
\layout Abstract
The VFS, or Virtual File System, handles all file system activity for phpGroupWa
re.
\layout Section
Introduction and Purpose
\begin_inset LatexCommand \label{sec:introduction}
\end_inset
\layout Standard
The latest version of the VFS for phpGroupWare combines actual file system
manipulation with fully integrated database support.
It features nearly transparent handling of files and directories, as well
as files inside and outside the virtual root.
This document is intended to provide API and application developers with
a guide to incorporating the VFS into their work.
\layout Section
Basics
\begin_inset LatexCommand \label{sec:basics}
\end_inset
\layout Subsection
Prerequisites
\begin_inset LatexCommand \label{sec:prerequisites}
\end_inset
\layout Standard
You must explicitly enable the VFS class.
To do this, set
\begin_inset Quotes eld
\end_inset
enable_vfs_class
\begin_inset Quotes erd
\end_inset
to True in $phpgw_info["flags"].
An example:
\layout Verbatim
$phpgw_info["flags"] = array("currentapp" => "phpwebhosting",
\layout Verbatim
"noheader" => False,
\layout Verbatim
"noappheader" => False,
\layout Verbatim
"enable_vfs_class" => True,
\layout Verbatim
"enable_browser_class" => True);
\layout Subsection
Concepts
\begin_inset LatexCommand \label{sec:concepts}
\end_inset
\layout Standard
The VFS in located in phpgwapi/inc/class.vfs.inc.php.
You can look over it, but I don't suggest trying to understand how it works.
It isn't necessary to know its internals to use it, but you may find the
inline comments helpful.
The basic things to keep in mind:
\layout Itemize
Files and directories are synonymous in almost all cases
\layout Verbatim
$phpgw->vfs->mv (
\begin_inset Quotes eld
\end_inset
file1
\begin_inset Quotes erd
\end_inset
,
\begin_inset Quotes eld
\end_inset
dir/file2
\begin_inset Quotes erd
\end_inset
);
\layout Verbatim
$phpgw->vfs->mv (
\begin_inset Quotes eld
\end_inset
dir1
\begin_inset Quotes erd
\end_inset
,
\begin_inset Quotes eld
\end_inset
dir/dir1
\begin_inset Quotes erd
\end_inset
);
\layout Verbatim
$phpgw->vfs->rm (
\begin_inset Quotes eld
\end_inset
file
\begin_inset Quotes erd
\end_inset
);
\layout Verbatim
$phpgw->vfs->rm (
\begin_inset Quotes eld
\end_inset
dir
\begin_inset Quotes erd
\end_inset
);
\layout Standard
All work as you would except them to.
The major exception is:
\layout Verbatim
$phpgw->vfs->touch (
\begin_inset Quotes eld
\end_inset
file
\begin_inset Quotes erd
\end_inset
);
\layout Standard
vs.
\layout Verbatim
$phpgw->vfs->mkdir (
\begin_inset Quotes eld
\end_inset
dir
\begin_inset Quotes erd
\end_inset
);
\layout Itemize
Users and groups and synonymous
\layout Standard
As far as the actual paths are concerned, users and groups are the same.
The VFS has no built in ACL support, so /home/username works the same as
/home/groupname.
See the note on ACL support in the Notes section.
\layout Itemize
You should never have to know the real path of files
\layout Standard
One of the VFS's responsibilities is to translate paths for you.
While you certainly
\emph on
can
\emph default
operate using full paths, it is much simpler to use the virtual paths.
For example, instead of using:
\layout Verbatim
$phpgw->vfs->cp (
\begin_inset Quotes eld
\end_inset
/var/www/phpgroupware/files/home/user/file1
\begin_inset Quotes erd
\end_inset
,
\begin_inset Quotes eld
\end_inset
/var/www/phpgroupware/files/home/user/file2
\begin_inset Quotes erd
\end_inset
, array (RELATIVE_NONE|VFS_REAL, RELATIVE_NONE|VFS_REAL));
\layout Standard
you might use
\layout Verbatim
$phpgw->vfs->cp (
\begin_inset Quotes eld
\end_inset
/home/user/file1
\begin_inset Quotes erd
\end_inset
,
\begin_inset Quotes eld
\end_inset
/home/user/file2
\begin_inset Quotes erd
\end_inset
, array (RELATIVE_NONE, RELATIVE_NONE));
\layout Standard
(We'll get to the RELATIVE's in a minute.)
\layout Standard
Site administrators should be able to move their files dir around on their
system and know that everything will continue to work smoothly.
\layout Itemize
Relativity is
\emph on
vital
\layout Standard
Relativity is a new feature in the VFS, and its importance cannot be stressed
enough.
It will make your life much easier, especially for file system intensive
applications, but it will take some getting used to.
If something doesn't work right the first time, chances are great it has
to do with incorrect relativity settings.
We will deal with relativity in depth in the Relativity section.
\layout Section
Basic Functions
\begin_inset LatexCommand \label{sec:basic_functions}
\end_inset
\layout Standard
These are two functions you'll need to know before we get into relativity.
\layout Subsection
path_parts ()
\begin_inset LatexCommand \label{sec:path_parts}
\end_inset
\layout Standard
The job of path_parts () is to translate any given file location into its
many component parts for any relativity.
The prototype for path_parts () is:
\layout Verbatim
function path_parts ($string, $relatives = array (RELATIVE_CURRENT), $object
= True)
\layout Standard
$string is the path you want to translate, $relatives is the standard relativity
array, and $object specifies how you would like the return value: if $object
is True, an object will be returned; if $object is False, an array will
be returned.
I think you'll find the object easier to deal with, and we'll be using
it throughout this document.
The most important returned values (but not all) for path_parts () are:
\layout Verbatim
fake_full_path
\layout Verbatim
fake_leading_dirs
\layout Verbatim
fake_extra_path
\layout Verbatim
fake_name
\layout Verbatim
real_full_path
\layout Verbatim
real_leading_dirs
\layout Verbatim
real_extra_path
\layout Verbatim
real_name
\layout Standard
Just like you would think, fake_full_path contains the full virtual path
of $string, and real_full_path contains the full real path of $string.
The fake_name and real_name variables should always be the same, and contain
the final file or directory name.
The leading_dirs contain everything except the name, and the extra_path
is everything from the / before
\begin_inset Quotes eld
\end_inset
home
\begin_inset Quotes erd
\end_inset
to the end of the leading_dirs.
To better illustrate, here is an example:
\layout Verbatim
$p = $phpgw->vfs->path_parts (
\begin_inset Quotes eld
\end_inset
/home/jason/dir/file
\begin_inset Quotes erd
\end_inset
, array (RELATIVE_NONE));
\layout Itemize
$p->fake_full_path - /home/jason/dir/file
\layout Itemize
$p->fake_leading_dirs - /home/jason/dir
\layout Itemize
$p->fake_extra_path - home/jason/dir
\layout Itemize
$p->fake_name - file
\layout Itemize
$p->real_full_path - /var/www/phpgroupware/files/home/jason/dir/file
\layout Itemize
$p->real_leading_dirs - /var/www/phpgroupware/files/home/jason/dir
\layout Itemize
$p->real_extra_path - home/jason/dir
\layout Itemize
$p->real_name - file
\layout Standard
As you can see, path_parts () is a very useful function and will save you
from doing those darn substr ()'s yourself.
For those of you used to the prior VFS, note that
\emph on
getabsolutepath () is depreciated
\emph default
.
getabsolutepath () still exists (albeit in a much different form), and
is responsible for some of the path translation, but it is an
\emph on
internal
\emph default
function only.
Applications should only use path_parts ().
We have shown you how to use path_parts () so you can experiment with it
using different paths and relativities as we explore relativity.
\layout Subsection
cd ()
\begin_inset LatexCommand \label{sec:cd}
\end_inset
\layout Standard
Part of the overall goal for the VFS in phpGroupWare is to give the user
a seamless experience during their session.
For example, if they upload a file using a file manager to /home/my_group/proje
ct1, and then go to download an email attachment, the default directory
will be /home/my_group/project1.
This is accomplished using the cd () function.
The prototype and examples:
\layout Verbatim
function cd ($target = "/", $relative = True, $relatives = array (RELATIVE_CURRE
NT))
\layout Verbatim
$phpgw->vfs->cd (
\begin_inset Quotes eld
\end_inset
/
\begin_inset Quotes erd
\end_inset
); /* cd to their home directory */
\layout Verbatim
$phpgw->vfs->cd (
\begin_inset Quotes eld
\end_inset
/home/jason/dir
\begin_inset Quotes erd
\end_inset
, False, array (RELATIVE_NONE)); /* cd to /home/jason/dir */
\layout Verbatim
$phpgw->vfs->cd (
\begin_inset Quotes eld
\end_inset
dir2
\begin_inset Quotes erd
\end_inset
, True); /* When following the above, cd's to /home/jason/dir/dir2 */
\layout Standard
If $relatives is True, the $target is simply appended to the current path.
If you want to know what the current path is, use $phpgw->vfs->pwd ().
\layout Standard
Now you're ready for relativity.
\layout Section
Relativity
\begin_inset LatexCommand \label{sec:relativity}
\end_inset
\layout Standard
Ok, just one last thing before we get into relativity.
You will notice throughout the examples the use of $fakebase.
$phpgw->vfs>fakebase is by default
\begin_inset Quotes eld
\end_inset
/home
\begin_inset Quotes erd
\end_inset
.
The old VFS was hard-coded to use
\begin_inset Quotes eld
\end_inset
/home
\begin_inset Quotes erd
\end_inset
, but the naming choice for this is now up to administrators.
See the
\begin_inset Quotes eld
\end_inset
Notes - Fakebase directory
\begin_inset Quotes erd
\end_inset
section for more information.
Throughout the rest of this document, you will see $fakebase used in calls
to the VFS, and /home used in actual paths.
\emph on
You should always use $fakebase when making applications.
\emph default
I suggest doing $fakebase = $phpgw->vfs->fakebase; right off the bat to
keep things neater.
\layout Subsection
What is it and how does it work?
\layout Standard
One of the design challenges for a Virtual File System is to try to figure
out whether the calling application is referring to a file inside or outside
the virtual root, and if inside, exactly where.
To solve this problem, the phpGroupWare VFS uses RELATIVE defines that
are used in bitmasks passed to each function.
The result is that any set of different relativities can be used in combination
with each other.
Let's look at a few examples.
Say you want to move
\begin_inset Quotes eld
\end_inset
logo.png
\begin_inset Quotes erd
\end_inset
from the user's home directory to the current directory.
\layout Verbatim
$phpgw->vfs->mv (
\begin_inset Quotes eld
\end_inset
logo.png
\begin_inset Quotes erd
\end_inset
,
\begin_inset Quotes eld
\end_inset
\begin_inset Quotes erd
\end_inset
, array (RELATIVE_USER, RELATIVE_ALL));
\layout Standard
RELATIVE_USER means relative to the user's home directory.
RELATIVE_ALL means relative to the current directory, as set by cd () and
as reported by pwd ().
So if the current directory was
\begin_inset Quotes eld
\end_inset
$fakebase/my_group/project1
\begin_inset Quotes erd
\end_inset
, the call to mv () would be processed as:
\layout Verbatim
MOVE
\begin_inset Quotes eld
\end_inset
$fakebase/jason/logo.png
\begin_inset Quotes erd
\end_inset
TO
\begin_inset Quotes eld
\end_inset
$fakebase/my_group/project1/logo.png
\begin_inset Quotes erd
\end_inset
\layout Standard
and the actual file system call would be:
\layout Verbatim
rename (
\begin_inset Quotes eld
\end_inset
/var/www/phpgroupware/files/home/jason/logo.php
\begin_inset Quotes erd
\end_inset
,
\begin_inset Quotes eld
\end_inset
/var/www/phpgroupware/files/home/my_group/project1/logo.png
\begin_inset Quotes erd
\end_inset
);
\layout Standard
Those used to the old VFS will note that you do not have to translate the
path beforehand.
Let's look at another example.
Suppose you were moving an email attachment stored in phpGroupWare's temporary
directory to the
\begin_inset Quotes eld
\end_inset
attachments
\begin_inset Quotes erd
\end_inset
directory within the user's home directory (we're assuming the attachments
directory exists).
Note that the temporary directory is
\emph on
outside
\emph default
the virtual root.
\layout Verbatim
$phpgw->vfs->mv (
\begin_inset Quotes eld
\end_inset
$phpgw_info[server][temp_dir]/$randomdir/$randomfile
\begin_inset Quotes erd
\end_inset
,
\begin_inset Quotes eld
\end_inset
attachments/actual_name.ext
\begin_inset Quotes erd
\end_inset
, array (RELATIVE_NONE|VFS_REAL, RELATIVE_USER));
\layout Standard
$randomdir and $randomfile are what the directory and file might be called
before they are given a proper name by the user, which is actual_name.ext
in this example.
RELATIVE_NONE is the define for using full path names.
However, RELATIVE_NONE is still relative to the virtual root, so we pass
along VFS_REAL as well, to say that the file is
\emph on
outside
\emph default
the virtual root, somewhere else in the file system.
Once again, RELATIVE_USER means relative to the user's home directory.
So the actual file system call might look like this (keep in mind that
$randomdir and $randomfile are just random strings):
\layout Verbatim
rename (
\begin_inset Quotes eld
\end_inset
/var/www/phpgroupware/tmp/0ak5adftgh7/jX42sC9M
\begin_inset Quotes erd
\end_inset
,
\begin_inset Quotes eld
\end_inset
/var/www/phpgroupware/files/home/jason/attachments/actual_name.ext
\begin_inset Quotes erd
\end_inset
);
\layout Standard
Of course you don't have to know that, nor should you be concerned with
it; you can take it for granted that the VFS will translate the paths correctly.
Let's take a look at one more example, this time using the RELATIVE_USER_APP
define.
RELATIVE_USER_APP is used to store quasi-hidden application files, similar
to the Unix convention of ~/.appname.
It simply appends .appname to the user's home directory.
For example, if you were making an HTML editor application named htmledit,
and wanted to keep a backup file in case something goes wrong, you would
use RELATIVE_USER_APP to store it:
\layout Verbatim
$phpgw->vfs->write (
\begin_inset Quotes eld
\end_inset
file.name~
\begin_inset Quotes erd
\end_inset
, array (RELATIVE_USER_APP), $contents);
\layout Standard
This assumes that ~/.htmledit exists of course.
The backup file
\begin_inset Quotes eld
\end_inset
file.name~
\begin_inset Quotes erd
\end_inset
would then be written in $fakebase/jason/.htmledit/file.name~.
Note that storing files like this might not be as good of a solution as
storing them in the temporary directory or in the database.
But it is there in case you need it.
\layout Subsection
Complete List
\begin_inset LatexCommand \label{sec:relatives_complete_list}
\end_inset
\layout Standard
Here is the complete list of RELATIVE defines, and what they do:
\layout Description
RELATIVE_ROOT Don't translate the path at all.
Just prepends a /.
You'll probably want to use RELATIVE_NONE though, which handles both virtual
and real files.
\layout Description
RELATIVE_USER User's home directory
\layout Description
RELATIVE_CURR_USER Current user's home directory.
If the current directory is $fakebase/my_group/project1, this will return
is $fakebase/my_group
\layout Description
RELATIVE_USER_APP Append .appname to the user's home directory, where appname
is the current application's appname
\layout Description
RELATIVE_PATH DO NOT USE.
Relative to the current directory, used in RELATIVE_ALL
\layout Description
RELATIVE_NONE Not relative to anything.
Use this with VFS_REAL for files outside the virtual root.
Note that using RELATIVE_NONE by itself still means relative to the virtual
root
\layout Description
RELATIVE_CURRENT An alias for the currently set RELATIVE define, or RELATIVE_ALL
if none is set (see the Defaults section)
\layout Description
VFS_REAL File is outside of the virtual root.
Usually used with RELATIVE_NONE
\layout Description
RELATIVE_ALL Relative to the current directory.
Use RELATIVE_ALL
\emph on
\emph default
instead of RELATIVE_PATH
\layout Subsection
Defaults
\begin_inset LatexCommand \label{sec:relatives_defaults}
\end_inset
\layout Standard
You might be thinking to yourself that passing along RELATIVE defines with
every VFS call is overkill, especially if your application always uses
the same relativity.
The default RELATIVE define for all VFS calls is RELATIVE_CURRENT.
RELATIVE_CURRENT itself defaults to RELATIVE_ALL (relative to the current
path),
\emph on
unless
\emph default
your application sets a specific relativity.
If your application requires most of the work to be done outside of the
virtual root, you may wish to set RELATIVE_CURRENT to RELATIVE_NONE|VFS_REAL.
set_relative () is the function to do this.
For example:
\layout Verbatim
$phpgw->vfs->set_relative (RELATIVE_NONE|VFS_REAL);
\layout Verbatim
$phpgw->vfs->read (
\begin_inset Quotes eld
\end_inset
/etc/passwd
\begin_inset Quotes erd
\end_inset
);
\layout Verbatim
$phpgw->vfs->cp (
\begin_inset Quotes eld
\end_inset
/usr/include/stdio.h
\begin_inset Quotes erd
\end_inset
,
\begin_inset Quotes eld
\end_inset
/tmp/stdio.h
\begin_inset Quotes erd
\end_inset
);
\layout Verbatim
$phpgw->vfs->cp (
\begin_inset Quotes eld
\end_inset
/usr/share/pixmaps/yes.xpm
\begin_inset Quotes erd
\end_inset
,
\begin_inset Quotes eld
\end_inset
icons/yes.xpm
\begin_inset Quotes erd
\end_inset
, array (RELATIVE_CURRENT, RELATIVE_USER));
\layout Standard
You should notice that no relativity array is needed in the other calls
that refer to files outside the virtual root, but one is needed for calls
that include files inside the virtual root.
Any RELATIVE define can be set as the default and works in the same fashion.
To retrieve the currently set define, use get_relative ().
Note that the relativity is reset after each page request; that is, it's
good only for the life of the current page loading, and is not stored in
session management.
\layout Section
Function reference
\begin_inset LatexCommand \label{sec:function_reference}
\end_inset
\layout Subsection
About
\begin_inset LatexCommand \label{sec:function_reference_about}
\end_inset
\layout Standard
This function reference is periodically auto-generated from the inline comments
in phpgwapi/inc/class.vfs.inc.php.
For the most up-to-date (and nicer looking) reference, see class.vfs.inc.php.
This reference is created as a separate DocBook document (using the inline2lyx.p
l script), so it might look a bit out of place.
\layout Subsection
class vfs
\begin_inset LatexCommand \label{sec: class vfs}
\end_inset
\layout Standard
abstract: virtual file system
\layout Standard
description: Authors: Zone, Seek3r
\layout Subsection
class path_class
\begin_inset LatexCommand \label{sec: class path_class}
\end_inset
\layout Standard
abstract: helper class for path_parts
\layout Subsection
vfs
\begin_inset LatexCommand \label{sec: vfs}
\end_inset
\layout Standard
abstract: constructor, sets up variables
\layout Verbatim
function vfs ()
\layout Subsection
set_relative
\begin_inset LatexCommand \label{sec: set_relative}
\end_inset
\layout Standard
abstract: Set path relativity
\layout Standard
param: $mask Relative bitmask (see RELATIVE_ defines)
\layout Verbatim
function set_relative ($mask)
\layout Subsection
get_relative
\begin_inset LatexCommand \label{sec: get_relative}
\end_inset
\layout Standard
abstract: Return relativity bitmask
\layout Standard
discussion: Returns relativity bitmask, or the default of "completely relative"
if unset
\layout Verbatim
function get_relative ()
\layout Subsection
sanitize
\begin_inset LatexCommand \label{sec: sanitize}
\end_inset
\layout Standard
abstract: Removes leading .'s from $string
\layout Standard
discussion: You should not pass all filenames through sanitize () unless
you plan on rejecting
\layout Standard
.files.
Instead, pass the name through securitycheck () first, and if it fails,
\layout Standard
pass it through sanitize
\layout Standard
param: $string string to sanitize
\layout Standard
result: $string without it's leading .'s
\layout Verbatim
function sanitize ($string)
\layout Subsection
securitycheck
\begin_inset LatexCommand \label{sec: securitycheck}
\end_inset
\layout Standard
abstract: Security check function
\layout Standard
discussion: Checks for basic violations such as ..
\layout Standard
If securitycheck () fails, run your string through vfs->sanitize ()
\layout Standard
param: $string string to check security of
\layout Standard
result: Boolean True/False.
True means secure, False means insecure
\layout Verbatim
function securitycheck ($string)
\layout Subsection
db_clean
\begin_inset LatexCommand \label{sec: db_clean}
\end_inset
\layout Standard
abstract: Clean $string for use in database queries
\layout Standard
param: $string String to clean
\layout Standard
result: Cleaned version of $string
\layout Verbatim
function db_clean ($string)
\layout Subsection
path_parts
\begin_inset LatexCommand \label{sec: path_parts}
\end_inset
\layout Standard
abstract: take a real or fake pathname and return an array of its component
parts
\layout Standard
param: $string full real or fake path
\layout Standard
param: $relatives Relativity array
\layout Standard
param: $object True returns an object instead of an array
\layout Standard
result: $rarray/$robject Array or object containing the fake and real component
parts of the path
\layout Standard
discussion: Returned values are:
\layout Standard
mask
\layout Standard
outside
\layout Standard
fake_full_path
\layout Standard
fake_leading_dirs
\layout Standard
fake_extra_path
\layout Standard
fake_name
\layout Standard
real_full_path
\layout Standard
real_leading_dirs
\layout Standard
real_extra_path
\layout Standard
real_name
\layout Standard
fake_full_path_clean
\layout Standard
fake_leading_dirs_clean
\layout Standard
fake_extra_path_clean
\layout Standard
fake_name_clean
\layout Standard
real_full_path_clean
\layout Standard
real_leading_dirs_clean
\layout Standard
real_extra_path_clean
\layout Standard
real_name_clean
\layout Standard
"clean" values are run through vfs->db_clean () and
\layout Standard
are safe for use in SQL queries that use key='value'
\layout Standard
They should be used ONLY for SQL queries, so are used
\layout Standard
mostly internally
\layout Standard
mask is either RELATIVE_NONE or RELATIVE_NONE|VFS_REAL,
\layout Standard
and is used internally
\layout Standard
outside is boolean, True if $relatives contains VFS_REAL
\layout Verbatim
function path_parts ($string, $relatives = array (RELATIVE_CURRENT), $object
= True)
\layout Subsection
getabsolutepath
\begin_inset LatexCommand \label{sec: getabsolutepath}
\end_inset
\layout Standard
abstract: get the absolute path
\layout Standard
param: $target defaults to False, directory/file to get path of, relative
to $relatives[0]
\layout Standard
param: $mask Relativity bitmask (see RELATIVE_ defines).
RELATIVE_CURRENT means use $this->relative
\layout Standard
param: $fake Returns the "fake" path, ie /home/user/dir/file (not always
possible.
use path_parts () instead)
\layout Standard
result: $basedir Full fake or real path
\layout Verbatim
function getabsolutepath ($target = False, $relatives = array (RELATIVE_CURRENT)
, $fake = True)
\layout Subsection
cd
\begin_inset LatexCommand \label{sec: cd}
\end_inset
\layout Standard
abstract: Change directory
\layout Standard
discussion: To cd to the files root "/", use cd ("/", False, array (RELATIVE_NON
E));
\layout Standard
param: $target default "/".
directory to cd into.
if "/" and $relative is True, uses "/home/<working_lid>";
\layout Standard
param: $relative default True/relative means add target to current path,
else pass $relative as mask to getabsolutepath()
\layout Verbatim
function cd ($target = "/", $relative = True, $relatives = array (RELATIVE_CURRE
NT))
\layout Subsection
pwd
\begin_inset LatexCommand \label{sec: pwd}
\end_inset
\layout Standard
abstract: current working dir
\layout Standard
param: $full default True returns full fake path, else just the extra dirs
(false strips the leading /)
\layout Standard
result: $currentdir currentdir
\layout Verbatim
function pwd ($full = True)
\layout Subsection
read
\begin_inset LatexCommand \label{sec: read}
\end_inset
\layout Standard
abstract: return file contents
\layout Standard
param: $file filename
\layout Standard
param: $relatives Relativity array
\layout Standard
result: $contents Contents of $file, or False if file cannot be read
\layout Verbatim
function read ($file, $relatives = array (RELATIVE_CURRENT))
\layout Subsection
write
\begin_inset LatexCommand \label{sec: write}
\end_inset
\layout Standard
abstract: write to a file
\layout Standard
param: $file file name
\layout Standard
param: $relatives Relativity array
\layout Standard
param: $contents contents
\layout Standard
result: Boolean True/False
\layout Verbatim
function write ($file, $relatives = array (RELATIVE_CURRENT), $contents)
\layout Subsection
touch
\begin_inset LatexCommand \label{sec: touch}
\end_inset
\layout Standard
abstract: Create blank file $file or set the modification time and modified
by of $file to current time and user
\layout Standard
param: $file File to touch or set modifies
\layout Standard
param: $relatives Relativity array
\layout Standard
result: Boolean True/False
\layout Verbatim
function touch ($file, $relatives = array (RELATIVE_CURRENT))
\layout Subsection
cp
\begin_inset LatexCommand \label{sec: cp}
\end_inset
\layout Standard
abstract: copy file
\layout Standard
param: $from from file/directory
\layout Standard
param: $to to file/directory
\layout Standard
param: $relatives Relativity array
\layout Standard
result: boolean True/False
\layout Verbatim
function cp ($from, $to, $relatives = array (RELATIVE_CURRENT, RELATIVE_CURRENT)
)
\layout Subsection
mv
\begin_inset LatexCommand \label{sec: mv}
\end_inset
\layout Standard
abstract: move file/directory
\layout Standard
param: $from from file/directory
\layout Standard
param: $to to file/directory
\layout Standard
param: $relatives Relativity array
\layout Standard
result: boolean True/False
\layout Verbatim
function mv ($from, $to, $relatives = array (RELATIVE_CURRENT, RELATIVE_CURRENT)
)
\layout Subsection
move
\begin_inset LatexCommand \label{sec: move}
\end_inset
\layout Standard
abstract: shortcut to mv
\layout Verbatim
function move ($from, $to, $relatives = array (RELATIVE_CURRENT, RELATIVE_CURREN
T))
\layout Subsection
rm
\begin_inset LatexCommand \label{sec: rm}
\end_inset
\layout Standard
abstract: delete file/directory
\layout Standard
param: $string file/directory to delete
\layout Standard
param: $relatives Relativity array
\layout Standard
result: boolean True/False
\layout Verbatim
function rm ($string, $relatives = array (RELATIVE_CURRENT))
\layout Subsection
delete
\begin_inset LatexCommand \label{sec: delete}
\end_inset
\layout Standard
abstract: shortcut to rm
\layout Verbatim
function delete ($string, $relatives = array (RELATIVE_CURRENT))
\layout Subsection
mkdir
\begin_inset LatexCommand \label{sec: mkdir}
\end_inset
\layout Standard
abstract: make a new directory
\layout Standard
param: $dir Directory name
\layout Standard
param: $relatives Relativity array
\layout Standard
result: boolean True on success
\layout Verbatim
function mkdir ($dir, $relatives = array (RELATIVE_CURRENT))
\layout Subsection
set_attributes
\begin_inset LatexCommand \label{sec: set_attributes}
\end_inset
\layout Standard
abstract: Update database entry for $file with the attributes in $attributes
\layout Standard
param: $file file/directory to update
\layout Standard
param: $relatives Relativity array
\layout Standard
param: $attributes keyed array of attributes.
key is attribute name, value is attribute value
\layout Standard
result: Boolean True/False
\layout Standard
discussion: Valid attributes are:
\layout Standard
owner_id
\layout Standard
createdby_id
\layout Standard
modifiedby_id
\layout Standard
created
\layout Standard
modified
\layout Standard
size
\layout Standard
mime_type
\layout Standard
deleteable
\layout Standard
comment
\layout Standard
app
\layout Verbatim
function set_attributes ($file, $relatives = array (RELATIVE_CURRENT), $attribut
es = array ())
\layout Subsection
correct_attributes
\begin_inset LatexCommand \label{sec: correct_attributes}
\end_inset
\layout Standard
abstract: Set the correct attributes for $string (e.g.
owner)
\layout Standard
param: $string File/directory to correct attributes of
\layout Standard
param: $relatives Relativity array
\layout Standard
result: Boolean True/False
\layout Verbatim
function correct_attributes ($string, $relatives = array (RELATIVE_CURRENT))
\layout Subsection
file_type
\begin_inset LatexCommand \label{sec: file_type}
\end_inset
\layout Standard
abstract: return file/dir type (MIME or other)
\layout Standard
param: $file File or directory path (/home/user/dir/dir2/dir3, /home/user/dir/di
r2/file)
\layout Standard
param: $relatives Relativity array
\layout Standard
result: MIME type, "Directory", or nothing if MIME type is not known
\layout Verbatim
function file_type ($file, $relatives = array (RELATIVE_CURRENT))
\layout Subsection
file_exists
\begin_inset LatexCommand \label{sec: file_exists}
\end_inset
\layout Standard
abstract: check if file/directory exists
\layout Standard
param: $string file/directory to check existance of
\layout Standard
param: $relatives Relativity array
\layout Standard
result: Boolean True/False
\layout Verbatim
function file_exists ($string, $relatives = array (RELATIVE_CURRENT))
\layout Subsection
checkperms
\begin_inset LatexCommand \label{sec: checkperms}
\end_inset
\layout Standard
abstract: Check if you have write access to create files in $dir
\layout Standard
discussion: This isn't perfect, because vfs->touch () returns True even
\layout Standard
if only the database entry worked.
ACLs need to be
\layout Standard
implemented for better permission checking.
It's
\layout Standard
also pretty slow, so I wouldn't recommend using it
\layout Standard
often
\layout Standard
param: $dir Directory to check access of
\layout Standard
param: $relatives Relativity array
\layout Standard
result: Boolean True/False
\layout Verbatim
function checkperms ($dir, $relatives = array (RELATIVE_CURRENT))
\layout Subsection
ls
\begin_inset LatexCommand \label{sec: ls}
\end_inset
\layout Standard
abstract: get directory listing
\layout Standard
discussion: Note: the entries are not guaranteed to be returned in any logical
order
\layout Standard
param: $dir Directory
\layout Standard
param: $relatives Relativity array
\layout Standard
param: $checksubdirs Boolean, recursively list all sub directories as well?
\layout Standard
param: $mime_type Only return entries matching MIME-type $mime_type.
Can be "Directory" or "
\backslash
" for those without MIME types
\layout Standard
param: $nofiles Boolean.
True means you want to return just the information about the directory
$dir.
If $dir is a file, $nofiles is implied.
This is the equivalent of 'ls -ld $dir'
\layout Standard
result: array of arrays.
Subarrays contain full info for each file/dir.
\layout Verbatim
function ls ($dir = False, $relatives = array (RELATIVE_CURRENT), $checksubdirs
= True, $mime_type = False, $nofiles = False)
\layout Subsection
dir
\begin_inset LatexCommand \label{sec: dir}
\end_inset
\layout Standard
abstract: shortcut to ls
\layout Verbatim
function dir ($dir = False, $relatives = array (RELATIVE_CURRENT), $checksubdirs
= True, $mime_type = False, $nofiles = False)
\layout Section
Notes
\begin_inset LatexCommand \label{sec:notes}
\end_inset
\layout Subsection
Database
\begin_inset LatexCommand \label{sec:database}
\end_inset
\layout Standard
Data about the files and directories within the virtual root is kept in
the SQL database.
Currently, this information includes:
\layout Itemize
File ID (used internally, primary key for table)
\layout Itemize
Owner ID (phpGW account_id)
\layout Itemize
Created by ID (phpGW account_id)
\layout Itemize
Modified by ID (phpGW account_id)
\layout Itemize
Created (date)
\layout Itemize
Modified (date)
\layout Itemize
Size (bytes)
\layout Itemize
MIME type
\layout Itemize
Deleteable (Y/N/Other?)
\layout Itemize
Comment
\layout Itemize
App (appname of application that created the file)
\layout Itemize
Directory (directory the file or directory is in)
\layout Itemize
Name (name of file or directory)
\layout Standard
The internal names of these (the database column names) are stored in the
$phpgw->vfs->attributes array, which is useful for loops, and is guaranteed
to be up-to-date.
\layout Standard
\layout Standard
Note that no information is kept about files outside the virtual root.
If a file is moved outside, all records of it are delete from the database.
If a file is moved into the virtual root, some information, specifically
MIME-type, is not stored in the database.
The vital information has defaults: owner is based on where the file is
being stored; size is correctly read; deleteable is set to Y.
\layout Subsection
ACL support
\begin_inset LatexCommand \label{sec:acl_support}
\end_inset
\layout Standard
Because of the many different ways the VFS can be used, complete ACL support
is not built in.
There is a bit of access control built in, just because of the way database
queries are made.
However, that is a discussion beyond the scope of this document.
Full ACL support may be added at a later time.
For now, it is fairly easy to add basic access control to your application
by matching path expressions.
The VFS always follows the same naming convention of $fakebase/userorgroup.
So if you need to check if a user has access to $fakebase/whatever/dir/file,
you need only know if they their username is 'whatever' or if they belong
to the group 'whatever', and that the group has access to your application.
Here is an example from PHPWebHosting:
\layout Verbatim
###
\layout Verbatim
# First we get their memberships
\layout Verbatim
###
\layout Verbatim
\layout Verbatim
$memberships = $phpgw->accounts->memberships ($account_id);
\layout Verbatim
\layout Verbatim
###
\layout Verbatim
# We determine if they're in their home directory or a group's directory
\layout Verbatim
# If they request a group's directory, we ensure they have access to the
group,
\layout Verbatim
# and the group has access to the app
\layout Verbatim
###
\layout Verbatim
\layout Verbatim
if ((preg_match ("+^$fakebase
\backslash
/(.*)(
\backslash
/|$)+U", $path, $matches)) && $matches[1] != $account_lid)
\layout Verbatim
{
\layout Verbatim
$phpgw->vfs->working_id = $phpgw->accounts->name2id ($matches[1]);
\layout Verbatim
reset ($memberships);
\layout Verbatim
while (list ($num, $group_array) = each ($memberships))
\layout Verbatim
{
\layout Verbatim
if ($matches[1] == $group_array["account_name"])
\layout Verbatim
{
\layout Verbatim
$group_ok = 1;
\layout Verbatim
break;
\layout Verbatim
}
\layout Verbatim
}
\layout Verbatim
if (!$group_ok)
\layout Verbatim
{
\layout Verbatim
echo $phpgw->common->error_list (array ("You do not have access
to group/directory $matches[1]"));
\layout Verbatim
exit;
\layout Verbatim
}
\layout Verbatim
}
\layout Standard
You should also check if the group has access to your appilcation.
\layout Subsection
Function aliases
\begin_inset LatexCommand \label{sec:function_aliases}
\end_inset
\layout Standard
You might have noticed there are some functions that just pass the arguments
on to other functions.
These are provided in part because of legacy and in part for convenience.
You can use either.
Here is the list (alias -> actual):
\layout Itemize
copy -> cp
\layout Itemize
move -> rm
\layout Itemize
delete -> rm
\layout Itemize
dir -> ls
\layout Subsection
Fakebase directory (changing /home)
\begin_inset LatexCommand \label{sec:fakebase}
\end_inset
\layout Standard
The old VFS was hard-coded to use "/home" as the fake base directory, even
though the user never saw it.
With the new system, crafty administrators may wish to change "/home" to
something else, say "/users" or "/public_html".
The fake base directory name is stored in $phpgw->vfs->fakebase, and changing
it will transparently change it throughout the VFS and all applications.
However, this must be done
\emph on
before
\emph default
any data is in the VFS database.
If you wish to change it afterwords, you'll have to manually update the
database, replacing the old value with the new value.
\emph on
Application programmers need to recognize that /home is not absolute, and
use $phpgw->vfs->fakebase instead
\emph default
.
I suggest setting $fakebase = $phpgw->vfs->fakebase; right off the bat
to keep things neater.
\layout Section
About this Document
\layout Subsection
Copyright and License
\layout Standard
Copyright (c) 2001 Jason Wies
\layout Standard
Permission is granted to copy, distribute and/or modify this document under
the terms of the GNU Free Documentation License, Version 1.1 or any later
version published by the Free Software Foundation; with no Invarient Sections,
with no Front-Cover Texts, and no Back-Cover Texts.
\layout Standard
A copy of the license is available at
\begin_inset LatexCommand \url[http://www.gnu.org/copyleft/fdl.html]{http://www.gnu.org/copyleft/fdl.html}
\end_inset
.
\layout Subsection
History
\layout Standard
Original document released in June 2001 by Jason Wies.
\layout Subsection
Contributing
\layout Standard
Contributions are always welcome.
Please send to the current maintainer, Jason Wies,
\begin_inset LatexCommand \url[zone@users.sourceforge.net]{mailto:zone@users.sourceforge.net}
\end_inset
.
\the_end