def open_read_file(file_name=None, dir=None, verbosity=1):
"""Open the file 'file' and return all the data.
@keyword file_name: The name of the file to extract the data from.
@type file_name: str
@keyword dir: The path where the file is located. If None, then the current directory is assumed.
@type dir: str
@keyword verbosity: The verbosity level.
@type verbosity: int
@return: The open file object.
@rtype: file object
"""
# A file descriptor object.
if is_filetype(file_name):
# Nothing to do here!
return file_name
# Invalid file name.
if not file_name and not isinstance(file_name, str):
raise RelaxError("The file name " + repr(file_name) + " " +
repr(type(file_name)) +
" is invalid and cannot be opened.")
# File path.
file_path = get_file_path(file_name, dir)
# Test if the file exists and determine the compression type.
compress_type, file_path = determine_compression(file_path)
# Open the file for reading.
try:
# Print out.
if verbosity:
print("Opening the file " + repr(file_path) + " for reading.")
# Uncompressed text.
if compress_type == 0:
file_obj = open(file_path, 'r')
# Bzip2 compressed text.
elif compress_type == 1:
file_obj = bz2_open(file=file_path, mode='r')
# Gzipped compressed text.
elif compress_type == 2:
file_obj = gz_open(file=file_path, mode='r')
# Cannot open.
except IOError:
message = sys.exc_info()[1]
raise RelaxError("Cannot open the file " + repr(file_path) + ". " +
message.args[1] + ".")
# Return the opened file.
return file_obj
def open_write_file(file_name=None,
dir=None,
force=False,
compress_type=0,
verbosity=1,
return_path=False):
"""Function for opening a file for writing and creating directories if necessary.
@keyword file_name: The name of the file to extract the data from.
@type file_name: str
@keyword dir: The path where the file is located. If None, then the current directory is assumed.
@type dir: str
@keyword force: Boolean argument which if True causes the file to be overwritten if it already exists.
@type force: bool
@keyword compress_type: The compression type. The integer values correspond to the compression type: 0, no compression; 1, Bzip2 compression; 2, Gzip compression. If no compression is given but the file name ends in '.gz' or '.bz2', then the compression will be automatically set.
@type compress_type: int
@keyword verbosity: The verbosity level.
@type verbosity: int
@keyword return_path: If True, the function will return a tuple of the file object and the full file path.
@type return_path: bool
@return: The open, writable file object and, if the return_path is True, then the full file path is returned as well.
@rtype: writable file object (if return_path, then a tuple of the writable file and the full file path)
"""
# No file name?
if file_name == None:
raise RelaxError("The name of the file must be supplied.")
# A file descriptor object.
if is_filetype(file_name):
# Nothing to do here!
return file_name
# Something pretending to be a file object.
if hasattr(file_name, 'write'):
# Nothing to do here!
return file_name
# The null device.
if search('devnull', file_name):
# Print out.
if verbosity:
print("Opening the null device file for writing.")
# Open the null device.
file_obj = open(devnull, 'w')
# Return the file.
if return_path:
return file_obj, None
else:
return file_obj
# Create the directories.
mkdir_nofail(dir, verbosity=0)
# File path.
file_path = get_file_path(file_name, dir)
# If no compression is supplied, determine the compression to be used from the file extension.
if compress_type == 0:
if search('.bz2$', file_path):
compress_type = 1
elif search('.gz$', file_path):
compress_type = 2
# Bzip2 compression.
if compress_type == 1 and not search('.bz2$', file_path):
# Bz2 module exists.
if bz2:
file_path = file_path + '.bz2'
# Switch to gzip compression.
else:
warn(
RelaxWarning(
"Cannot use Bzip2 compression, using gzip compression instead. "
+ bz2_module_message + "."))
compress_type = 2
# Gzip compression.
if compress_type == 2 and not search('.gz$', file_path):
file_path = file_path + '.gz'
# Fail if the file already exists and the force flag is set to 0.
if access(file_path, F_OK) and not force:
raise RelaxFileOverwriteError(file_path, 'force flag')
# Open the file for writing.
try:
# Print out.
if verbosity:
print("Opening the file " + repr(file_path) + " for writing.")
# Uncompressed text.
if compress_type == 0:
file_obj = open(file_path, 'w')
# Bzip2 compressed text.
elif compress_type == 1:
file_obj = bz2_open(file=file_path, mode='w')
# Gzipped compressed text.
elif compress_type == 2:
file_obj = gz_open(file=file_path, mode='w')
# Cannot open.
except IOError:
message = sys.exc_info()[1]
raise RelaxError("Cannot open the file " + repr(file_path) + ". " +
message.args[1] + ".")
# Return the opened file.
if return_path:
return file_obj, file_path
else:
return file_obj