cloud-init-dev team mailing list archive

[Scott Moser <ssmoser2+ubuntu@xxxxxxxxx>]

I think that this will not really get you what you're after.
Having a list of the files that cloud-init created or appended to or truncated isn't going to get you to your goal. The partial solution comes at the cost of 2 open and writes for every write.  Additionally, we're already writing messages with the same information to the log.  You could just parse the log to get the same information, possibly making it more machine friendly if you need to.

I think I'd prefer a solution that could at least get us to the goal.

Diff comments:

> diff --git a/cloudinit/util.py b/cloudinit/util.py
> index aa23b3f..950921c 100644
> --- a/cloudinit/util.py
> +++ b/cloudinit/util.py
> @@ -1841,6 +1843,55 @@ def chmod(path, mode):
>              os.chmod(path, real_mode)
>  
>  
> +def write_file_log_append(filename, omode, target=None):
> +    """ Create an audit log of files that cloud-init has written.
> +
> +    The log is located at: /var/lib/cloud/instance/write_file.log
> +
> +    The format is JSON dict, one per line
> +      {'timestamp': time.time(), 'path': filename, 'mode': omode}
> +
> +    Example entries:
> +      {'filename': '/etc/apt/sources.list', 'mode': 'wb', 'timestamp': ts}
> +
> +    """
> +    global WRITE_FILE_LOG
> +    global _ENABLE_WRITE_FILE_LOG
> +
> +    if not _ENABLE_WRITE_FILE_LOG:
> +        return
> +
> +    log_file = target_path(target, path=WRITE_FILE_LOG)
> +    if not os.path.exists(os.path.dirname(log_file)):
> +        return
> +
> +    record = {'timestamp': time.time(), 'filename': filename, 'mode': omode}
> +    content = json.dumps(record, default=json_serialize_default)
> +    try:
> +        with open(log_file, "ab") as wfl:
> +            wfl.write((content + '\n').encode('utf-8'))
> +            wfl.flush()
> +    except IOError as e:
> +        LOG.debug('Failed to append to write file log (%s): %s', log_file, e)
> +
> +
> +def write_file_log_read(target=None):

today (for the second time) i read this function name and assumed that it was 'write'ing something.
like 'write_file' writes a file. 
maybe: read_global_write_log() ?

> +    """ Read the WRITE_FILE_LOG and yield the contents.
> +
> +    :returns a list of record dicts
> +    """
> +    global WRITE_FILE_LOG
> +
> +    log_file = target_path(target, path=WRITE_FILE_LOG)
> +    if os.path.exists(log_file):
> +        with open(log_file, "rb") as wfl:
> +            contents = wfl.read()
> +        for line in contents.splitlines():
> +            record = load_json(line)
> +            if record:
> +                yield record
> +
> +
>  def write_file(filename, content, mode=0o644, omode="wb", copy_mode=False):
>      """
>      Writes a file with the given content and sets the file mode as specified.


-- 
https://code.launchpad.net/~raharper/cloud-init/+git/cloud-init/+merge/372946
Your team cloud-init Commiters is requested to review the proposed merge of ~raharper/cloud-init:feature/cloudinit-clean-from-write-log into cloud-init:master.