def save_text_to(text, file_path, overwrite=False):
if os.path.exists(file_path) and not overwrite:
raise exc.DataAccessException(
"Cannot save data to file. File %s already exists.")
with open(file_path, 'w') as f:
f.write(text)
def rollback_tx():
"""Rolls back previously started database transaction."""
ses = _get_thread_local_session()
if not ses:
raise exc.DataAccessException(
"Nothing to roll back. Database transaction has not been started.")
ses.rollback()
def commit_tx():
"""Commits previously started database transaction."""
ses = _get_thread_local_session()
if not ses:
raise exc.DataAccessException("Nothing to commit. Database transaction"
" has not been previously started.")
ses.commit()
def start_tx():
"""Starts transaction.
Opens new database session and starts new transaction assuming
there wasn't any opened sessions within the same thread.
"""
if _get_thread_local_session():
raise exc.DataAccessException(
"Database transaction has already been started.")
_set_thread_local_session(_get_session())
def generate_key_pair(key_length=2048):
"""Create RSA key pair with specified number of bits in key.
Returns tuple of private and public keys.
"""
with tempdir() as tmpdir:
keyfile = os.path.join(tmpdir, 'tempkey')
args = [
'ssh-keygen',
'-q', # quiet
'-N',
'', # w/o passphrase
'-t',
'rsa', # create key of rsa type
'-f',
keyfile, # filename of the key file
'-C',
'Generated-by-Mistral' # key comment
]
if key_length is not None:
args.extend(['-b', key_length])
processutils.execute(*args)
if not os.path.exists(keyfile):
raise exc.DataAccessException(
"Private key file hasn't been created")
private_key = open(keyfile).read()
public_key_path = keyfile + '.pub'
if not os.path.exists(public_key_path):
raise exc.DataAccessException(
"Public key file hasn't been created")
public_key = open(public_key_path).read()
return private_key, public_key
def end_tx():
"""Ends transaction.
Ends current database transaction.
It rolls back all uncommitted changes and closes database session.
"""
ses = _get_thread_local_session()
if not ses:
raise exc.DataAccessException(
"Database transaction has not been started.")
if ses.dirty:
rollback_tx()
ses.close()
_set_thread_local_session(None)
def tempdir(**kwargs):
argdict = kwargs.copy()
if 'dir' not in argdict:
argdict['dir'] = '/tmp/'
tmpdir = tempfile.mkdtemp(**argdict)
try:
yield tmpdir
finally:
try:
shutil.rmtree(tmpdir)
except OSError as e:
raise exc.DataAccessException(
"Failed to delete temp dir %(dir)s (reason: %(reason)s)" %
{'dir': tmpdir, 'reason': e}
)
