Re: [PATCHv1 1/3] git-p4: raise exceptions from p4CmdList based on error from p4 server

> This change lays some groundwork for better handling of rowcount errors
> from the server, where it fails to send us results because we requested
> too many.
>
> It adds an option to p4CmdList() to return errors as a Python exception.
>
> The exceptions are derived from P4Exception (something went wrong),
> P4ServerException (the server sent us an error code) and
> P4RequestSizeException (we requested too many rows/results from the
> server database).
>
> This makes makes the code that handles the errors a bit easier.
>
> The default behavior is unchanged; the new code is enabled with a flag.
>
> Signed-off-by: Luke Diamand <luke@diamand.org>
> ---
> diff --git a/git-p4.py b/git-p4.py
> @@ -566,10 +566,30 @@ def isModeExec(mode):
> +class P4ServerException(Exception):
> +    """ Base class for exceptions where we get some kind of marshalled up result from the server """
> +    def __init__(self, exit_code, p4_result):
> +        super(P4ServerException, self).__init__(exit_code)
> +        self.p4_result = p4_result
> +        self.code = p4_result[0]['code']
> +        self.data = p4_result[0]['data']

> @@ -616,9 +636,25 @@ def p4CmdList(cmd, stdin=None, stdin_mode='w+b', cb=None, skip_info=False):
>      if exitCode != 0:
> -        entry = {}
> -        entry["p4ExitCode"] = exitCode
> -        result.append(entry)
> +        if errors_as_exceptions:
> +            if len(result) > 0:
> +                data = result[0].get('data')
> +                if data:
> +                    m = re.search('Too many rows scanned \(over (\d+)\)', data)
> +                    if not m:
> +                        m = re.search('Request too large \(over (\d+)\)', data)

> +                    if m:
> +                        limit = int(m.group(1))
> +                        raise P4RequestSizeException(exitCode, result, limit)
> +
> +                raise P4ServerException(exitCode, result)
> +            else:
> +                raise P4Exception(exitCode)
> +        else:
> +            entry = {}
> +            entry["p4ExitCode"] = exitCode
> +            result.append(entry)