pycloudlib.util module

Helpers for shell string and processing.

pycloudlib.util.add_key_to_cloud_config(public_key: str, user_data: str | None = None)

Add a public key to the cloud-config.

pycloudlib.util.chmod(path, mode)

Run chmod on a file or directory.

Parameters:

• path – string of path to run on

• mode – int of mode to apply

pycloudlib.util.get_query_param(uri: str, param: str) → list

Extract query query params of param from uri.

>>> url = "https://cloud.com/v1/vpcs?limit=1&start=r134-fe06d70f"
>>> get_query_param(url, "start")
['r134-fe06d70f']

pycloudlib.util.get_query_params(uri: str) → Dict[str, list]

Extract query params from uri.

>>> url = "https://cloud.com/v1/vpcs?limit=1&start=r134-fe06d70f"
>>> get_query_params(url)
{'limit': ['1'], 'start': ['r134-fe06d70f']}

pycloudlib.util.get_timestamped_tag(tag)

Create tag with current timestamp.

Parameters:

tag – string, Base tag to be used

Returns

An updated tag with current timestamp

pycloudlib.util.is_writable_dir(path)

Make sure dir is writable.

Parameters:

path – path to determine if writable

Returns:

boolean with result

pycloudlib.util.log_exception_list(exceptions: List[Exception])

Print a list of exceptions (including traceback) to stderr.

pycloudlib.util.mkdtemp(prefix='pycloudlib')

Make a temporary directory.

Parameters:

prefix – optional, temproary dir name prefix (default: pycloudlib)

Returns:

tempfile object that was created

pycloudlib.util.rmfile(path)

Delete a file.

Parameters:

path – run unlink on specific path

pycloudlib.util.shell_pack(cmd)

Return a string that can shuffled through ‘sh’ and execute cmd.

In Python subprocess terms:

check_output(cmd) == check_output(shell_pack(cmd), shell=True)

Parameters:

cmd – list or string of command to pack up

Returns:

base64 encoded string

pycloudlib.util.shell_quote(cmd)

Quote a shell string.

Parameters:

cmd – command to quote

Returns:

quoted string

pycloudlib.util.shell_safe(cmd)

Produce string safe shell string.

Create a string that can be passed to $(set – <string>) to produce the same array that cmd represents.

Internally we utilize ‘getopt’s ability/knowledge on how to quote strings to be safe for shell. This implementation could be changed to be pure python. It is just a matter of correctly escaping or quoting characters like: ‘ “ ^ & $ ; ( ) …

Parameters:

cmd – command as a list

Returns:

shell safe string

pycloudlib.util.subp(args, data=None, env=None, shell=False, rcs=(0,), shortcircuit_stdin=True)

Subprocess wrapper.

Parameters:

• args – command to run

• data – data to pass

• env – optional env to use

• shell – optional shell to use

• rcs – tuple of successful exit codes, default: (0)

• shortcircuit_stdin – bind stdin to /dev/null if no data is given

Returns:

Tuple of out, err, return_code

pycloudlib.util.touch(path, mode=None)

Ensure a directory exists with a specific mode, it not create it.

Parameters:

• path – path to directory to create

• mode – optional, mode to set directory to

pycloudlib.util.update_nested(mapping, update)

Update mapping with update value at given update key.

Example

original_dict = {‘a’: {‘b’: {‘c’: ‘d’}}} update = {‘a’: {‘b’: {‘c’: ‘e’}}} update_nested(original_dict, update) original_dict == {‘a’: {‘b’: {‘c’: ‘e’}}}