def get_file_name(self):
"""Display a prompt to the user requesting data.
Returns:
str: The file name given by the user.
"""
return io.prompt_valid_file_name('Enter test data file:')
def execute(self, maximum_list_length):
"""Prompt user for a file and have them enter values to write into it.
Arguments:
maximum_list_length(int): The maximum allowed list length.
"""
output_file = io.prompt_valid_file_name(
'Please enter the file to write: ')
if os.path.isfile(output_file):
self.prompt_overwrite_or_change(output_file, maximum_list_length)
if not os.path.exists(os.path.dirname(output_file)):
self.directory_does_not_exist(output_file, maximum_list_length)
total_num_entries = int(io.get_and_confirm_input(
'How many numbers will you enter: '))
num_entries_given = 0
entries = []
while num_entries_given < total_num_entries:
value = io.get_and_confirm_list(
'Entry {}: '.format(num_entries_given + 1),
max_list_length=maximum_list_length)
entries.append(value)
num_entries_given += 1
io.write_lists_to_file(output_file, entries)
print 'Results written to {}'.format(output_file)
def main():
"""Application entry point"""
print "This program will read or write numbers to or from a given file."
print 'Read - Read and display numbers in a file'
print 'Write - Input numbers to write to a file'
print 'Add - Go through file line-by-line and add new numbers'
print 'Modify - Go through file line by line and modify numbers'
mode = io.choose_from_list(
'Choose a mode',
['Read', 'Write', 'Add', 'Modify']
)
mode = mode.lower()
if mode in ['write']:
file_path = io.prompt_valid_file_name('Please enter a file name: ')
else:
file_path = io.prompt_existant_file_name('Please enter a file name: ')
if mode == 'read':
read_file(file_path)
elif mode == 'write':
write_file(file_path)
elif mode == 'add':
add_file(file_path)
elif mode == 'modify':
modify_file(file_path)
else:
raise RuntimeError('Invalid option {}'.format(mode))
def get_file_name(self):
"""Display a prompt to the user requesting data.
Returns:
str: The file name given by the user.
"""
try:
return io.prompt_valid_file_name('Enter test data file:')
except RuntimeError as re:
self.display_error('Invalid or missing test file provided.')
raise re
def write_file(file_path):
"""Requests a series of numerical inputs and writes them to the file.
Arguments:
file_path(basestring): The path to the file
"""
if os.path.isfile(file_path):
should_overwrite = io.yes_no_prompt(
'File {} exists. Overwrite?'.format(file_path))
# If the file shouldn't be overwritten, abort
if not should_overwrite:
enter_different_file = io.yes_no_prompt(
'Would you like to enter a different file name?')
if enter_different_file:
file_path = io.prompt_valid_file_name('New file name: ')
write_file(file_path)
sys.exit('Aborting. Not overwriting existing file.')
if not os.path.exists(os.path.dirname(file_path)):
print 'ERROR: Directory for file {} does not exist'.format(file_path)
io.prompt_try_again_or_abort()
file_path = io.prompt_valid_file_name('New file name: ')
write_file(file_path)
total_num_entries = io.get_and_confirm_input(
'How many numbers will you enter: ')
total_num_entries = int(total_num_entries)
num_entries_given = 0
with open(file_path, 'w') as wfile:
while num_entries_given < total_num_entries:
value = io.get_and_confirm_float(
'Entry #{}: '.format(num_entries_given + 1))
value = float(value)
wfile.write('{}\n'.format(value))
num_entries_given += 1
def prompt_for_output_file(original_file_name):
"""Prompt for the file to output data into
Arguments:
original_file_name(str): The original file name.
Returns:
str: The new file name if a new file is entered, otherwise the original
file name.
"""
print 'Original file: {}'.format(original_file_name)
choice = io.binary_choice('Output file (s)ame/(n)ew file? ', 's', 'n')
if choice == 'n':
new_file_name = io.prompt_valid_file_name('New file name: ')
return new_file_name
return original_file_name
def prompt_output_file(self, prompt, maximum_attempts=5):
"""Prompt the user to enter a valid output file.
Arguments:
prompt(basestring): The prompt to be displayed.
maximum_attempts(int): Default 5, the maximum number of attempts
a user has to enter a valid output file name.
Returns:
basestring: The output file path.
"""
while maximum_attempts > 0:
output_file = io.prompt_valid_file_name(prompt)
if not os.path.exists(output_file):
return output_file
if io.yes_no_prompt(
'File {} already exists. Overwrite?'.format(output_file)):
return output_file
maximum_attempts -= 1
raise RuntimeError('Maximum attempts exceeded.')
