# $Id: FileTest.py,v 1.1 2002/05/13 14:38:15 graham Exp $
#
# RDF FileTest class for performing various tests on files.  This module
# has been written to isolate some system dependencies when porting code
# between regular Python and Jython.
#
#--------+---------+---------+---------+---------+---------+---------+---------+
#
# Copyright (c) 2002, G. KLYNE
# All rights reserved.
#
# Redistribution and use in source and binary forms, with or without
# modification, are permitted provided that the following conditions
# are met:
# 1. Redistributions of source code must retain the above copyright
#    notice, this list of conditions and the following disclaimer.
# 2. Redistributions in binary form must reproduce the above copyright
#    notice, this list of conditions and the following disclaimer in the
#    documentation and/or other materials provided with the distribution.
# 3. The name of the author may not be used to endorse or promote products
#    derived from this software without specific prior written permission.
#
# THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
# IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
# OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
# IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
# INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
# NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
# THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
#
#--------+---------+---------+---------+---------+---------+---------+---------+
# $Source: /file/cvsdev/PythonN3/FileTest.py,v $
# $Author: graham $
# $Revision: 1.1 $ $Date: 2002/05/13 14:38:15 $
#--------+---------+---------+---------+---------+---------+---------+---------+
#        1         2         3         4         5         6         7         8

import os
#import re
import sys
import string
from stat import *

#--------+---------+---------+---------+---------+---------+---------+---------+
# FileTest - class for testing filenames
#
class FileTest:
    """
    Perform various file-related tests.

    This module has been written to isolate some system dependencies when
    porting code between regular Python and Jython.
    """
    # End of FileTest

def exists( DirPath, FileName ):
    """
    Test if named file in specified directory exists, either as a file
    or as a directory.
    
    Parameters:
      DirPath       path of directory where file resides, or None
      FileName      name of file to be tested
    
    Returns:
      A fully qualified filename string if the file exists, otherwise
      None.
    """
    if not DirPath:
        DirPath = os.getcwd()
    FullName = os.path.normpath( os.path.join( DirPath, FileName ) )
    if os.path.exists( FullName ): return FullName
    return None

def isFile( DirPath, FileName ):
    """
    Test if named file in specified directory exists as a file.
    
    Parameters:
      DirPath       path of directory where file resides, or None
      FileName      name of file to be tested
    
    Returns:
      A fully qualified filename string if the file exists, otherwise
      None.
    """
    FullName = exists( DirPath, FileName )
    if FullName:
        if os.path.isfile( FullName ): return FullName
    return None

def isDirectory( DirPath, FileName ):
    """
    Test if named file in specified directory exists as a directory.
    
    Parameters:
      DirPath       path of directory where file resides, or None
      FileName      name of file to be tested
    
    Returns:
      A fully qualified filename string if the file exists, otherwise
      None.
    """
    FullName = exists( DirPath, FileName )
    if FullName:
        if os.path.isdir( FullName ): return FullName
    return None

def canRead( DirPath, FileName ):
    """
    Test if named file in specified directory can be read.
    
    Parameters:
      DirPath       path of directory where file resides, or None
      FileName      name of file to be tested
    
    Returns:
      A true value if the indicated file can be read by the calling program,
      otherwise a false value.
    """
    FullName = exists( DirPath, FileName )
    if FullName:
        ### if checkMode( FullName, 0x124 ): return FullName
        if os.access( FullName, os.R_OK ): return FullName
    return None

def canWrite( DirPath, FileName ):
    """
    Test if named file in specified directory can be written or created.
    
    Parameters:
      DirPath       path of directory where file resides, or None
      FileName      name of file to be tested
    
    Returns:
      A true value if the indicated file can be written or created by the 
      calling program, otherwise a false value.
    """
    FullName = exists( DirPath, FileName )
    if FullName:
        ### if checkMode( FullName, 0x092 ): return FullName
        if os.access( FullName, os.W_OK ): return FullName
    else:
        return canCreate( DirPath, FileName )
    return None

def canCreate( DirPath, FileName ):
    """
    Test if named file in specified directory can be created.
    
    
    Parameters:
      DirPath       path of directory where file resides, or None
      FileName      name of file to be tested
    
    Returns:
      A true value if the indicated file can be created by the 
      calling program, otherwise a false value if the file already exists
      or the directory is not writeable.
    """
    if not FileName: return None
    FullName = exists( DirPath, FileName )
    if FullName: return None
    FullName = os.path.normpath( os.path.join( DirPath, FileName ) )
    DirName  = os.path.dirname( FullName )
    if not DirName: DirName = os.getcwd()
    #### if checkMode( DirName, 0x092 ): return FullName
    if os.access( DirName, os.W_OK ): return FullName
    return None

def checkMode( FullName, Mode ):
    """
    Local helper function checks file access mode against supplied value:
    returns true value if any of the required mode bits are set,
    otherwise false.
    """
    Stat = os.stat( FullName )
    FileMode = S_IMODE( Stat[ST_MODE] )
    sys.stdout.write( "    Mode for "+FullName+" is "+hex(FileMode)+"\n" )
    # For now:
    # base writeability assessent on union of owner, group, world permissions
    return FileMode & Mode

#--------+---------+---------+---------+---------+---------+---------+---------+
#
# Stand-alone test code follows:
#

if __name__ == '__main__':
    sys.stdout.write( "FileTest tests\n" )

    ### Change this to match the running environment
    ### CurrentDir = "D:\Dev\PythonN3"
    CurrentDir    = os.getcwd()
    PathSeparator = os.sep

    sys.stdout.write( "os.getcwd(): "+os.getcwd()+"\n" )
    sys.stdout.write( "os.sep:      "+repr(os.sep)+"\n" )
    sys.stdout.write( "os.altsep:   "+repr(os.altsep)+"\n" )
    sys.stdout.write( "os.pathsep:  "+repr(os.pathsep)+"\n" )
    sys.stdout.write( "os.name:     "+repr(os.name)+"\n" )


    sys.stdout.write( "exists() tests:\n" )
    e1 = exists( ".", "FileTest.py" )
    if not e1:
        sys.stdout.write( "exists( '.', 'FileTest.py' ) returned false.\n" )
    elif e1 != "FileTest.py":
        sys.stdout.write( "exists( '.', 'FileTest.py' ) returned '"+e1+"'\n" )
    e2 = exists( None, "FileTest.py" )
    if not e2:
        sys.stdout.write( "exists( None, 'FileTest.py' ) returned false.\n" )
    elif e2 != CurrentDir + PathSeparator + "FileTest.py":
        sys.stdout.write( "exists( None, 'FileTest.py' ) returned '"+e2+"'\n" )
    e3 = exists( ".", "FileTest.none" )
    if e3:
        sys.stdout.write( "exists( '.', 'FileTest.None' ) returned '"+e3+"'\n" )
    n4 = os.path.dirname( e2 )
    e4 = exists( None, n4 )
    if not e4:
        sys.stdout.write( "exists( None, "+n4+" ) returned false.\n" )
    elif e4 != CurrentDir:
        sys.stdout.write( "exists( None, "+n4+" ) returned '"+e4+"'\n" )

    sys.stdout.write( "isFile() tests:\n" )
    f1 = isFile( ".", "FileTest.py" )
    if not f1:
        sys.stdout.write( "isFile( '.', 'FileTest.py' ) returned false.\n" )
    elif f1 != "FileTest.py":
        sys.stdout.write( "isFile( '.', 'FileTest.py' ) returned '"+f1+"'\n" )
    f2 = isFile( None, "FileTest.py" )
    if not f2:
        sys.stdout.write( "isFile( None, 'FileTest.py' ) returned false.\n" )
    elif f2 != CurrentDir + PathSeparator + "FileTest.py":
        sys.stdout.write( "isFile( None, 'FileTest.py' ) returned '"+f2+"'\n" )
    f3 = isFile( ".", "FileTest.none" )
    if f3:
        sys.stdout.write( "isFile( '.', 'FileTest.None' ) returned '"+f3+"'\n" )
    n4 = os.path.dirname( e2 )
    f4 = isFile( None, n4 )
    if f4:
        sys.stdout.write( "isFile( None, "+n4+" ) returned '"+f4+"'\n" )

    sys.stdout.write( "isDirectory() tests:\n" )
    d1 = isDirectory( ".", "FileTest.py" )
    if d1:
        sys.stdout.write( "isDirectory( '.', 'FileTest.py' ) returned '"+d1+"'\n" )
    d2 = isDirectory( None, "FileTest.py" )
    if d2:
        sys.stdout.write( "isDirectory( None, 'FileTest.py' ) returned '"+d2+"'\n" )
    d3 = isDirectory( ".", "FileTest.none" )
    if d3:
        sys.stdout.write( "isDirectory( '.', 'FileTest.None' ) returned '"+d3+"'\n" )
    n4 = os.path.dirname( e2 )
    d4 = isDirectory( None, n4 )
    if not d4:
        sys.stdout.write( "isDirectory( None, "+n4+" ) returned false.\n" )
    elif d4 != CurrentDir:
        sys.stdout.write( "isDirectory( None, "+n4+" ) returned '"+d4+"'\n" )

    sys.stdout.write( "canRead() tests:\n" )
    r1 = canRead( ".", "FileTest.py" )
    if not r1:
        sys.stdout.write( "canRead( '.', 'FileTest.py' ) returned false.\n" )
    elif r1 != "FileTest.py":
        sys.stdout.write( "canRead( '.', 'FileTest.py' ) returned '"+r1+"'\n" )
    r2 = canRead( None, "FileTest.py" )
    if not r2:
        sys.stdout.write( "canRead( None, 'FileTest.py' ) returned false.\n" )
    elif r2 != CurrentDir + PathSeparator + "FileTest.py":
        sys.stdout.write( "canRead( None, 'FileTest.py' ) returned '"+r2+"'\n" )
    r3 = canRead( ".", "FileTest.none" )
    if r3:
        sys.stdout.write( "canRead( '.', 'FileTest.None' ) returned '"+r3+"'\n" )

    sys.stdout.write( "canWrite() tests\n" )
    w1 = canWrite( ".", "FileTest.py" )
    if not w1:
        sys.stdout.write( "canWrite( '.', 'FileTest.py' ) returned false.\n" )
    elif w1 != "FileTest.py":
        sys.stdout.write( "canWrite( '.', 'FileTest.py' ) returned '"+w1+"'\n" )
    w2 = canWrite( None, "FileTest.py" )
    if not w2:
        sys.stdout.write( "canWrite( None, 'FileTest.py' ) returned false.\n" )
    elif w2 != CurrentDir + PathSeparator + "FileTest.py":
        sys.stdout.write( "canWrite( None, 'FileTest.py' ) returned '"+w2+"'\n" )
    w3 = canWrite( ".", "FileTest.new" )
    if not w3:
        sys.stdout.write( "canWrite( '.', 'FileTest.new' ) returned false.\n" )
    elif w3 != "FileTest.new":
        sys.stdout.write( "canWrite( '.', 'FileTest.new' ) returned '"+w3+"'\n" )

    sys.stdout.write( "canCreate() tests\n" )
    c1 = canCreate( ".", "FileTest.py" )
    if c1:
        sys.stdout.write( "canCreate( '.', 'FileTest.py' ) returned '"+c1+"'\n" )
    c2 = canCreate( None, "FileTest.py" )
    if c2:
        sys.stdout.write( "canCreate( None, 'FileTest.py' ) returned '"+c2+"'\n" )
    c3 = canCreate( ".", "FileTest.new" )
    if not c3:
        sys.stdout.write( "canCreate( '.', 'FileTest.new' ) returned false.\n" )
    elif c3 != "FileTest.new":
        sys.stdout.write( "canCreate( '.', 'FileTest.new' ) returned '"+c3+"'\n" )

    sys.stdout.write( "Exiting\n" )

#--------+---------+---------+---------+---------+---------+---------+---------+
#
# $Log: FileTest.py,v $
# Revision 1.1  2002/05/13 14:38:15  graham
# Add Jython capability to test for file readability/writability
#
#