I don't necessarily think all of these make the code better or easier to read, but it's easier to just go along with what the tools want, since they do generally make things better.
There should be no functional changes here.
I noticed this while testing the change that added the --json option, though it is not related to that change.
Sequence types get mushed into a string when not in JSON mode, and that was turning None object values into the string "None", which is not desirable. So, similar to how the text output script handles it, those now get emitted as an empty string instead. JSON mode is probably better to use for this type of data, anyway, but it was bugging me to have it report as "None".
Per discussion in PR #40 comments. This will prevent a stack dump from littering the output when interrupting script run via Control-C. That was useful to have for a while, but probably is not anymore.
Also, fix up a few corner cases where rc could be used without it having been set.
Adjust how the --poll-loops option handles the first set of polled loops for history stats, to make that set of data run against a number of samples (and therefore total time interval) that more closely matches subsequent sets of polled loops. This especially applies to the case where the stats are resuming from a prior counter, where without this logic, the first set had an unintuitively large number of samples.
Fix timestamp reporting for history stats to better reflect the actual accumulated data, for cases where later polls of the history data had failed. This introduced the potential for the status data and the history stats data to have inconsistent timestamps, and required the timestamp collection to be moved from the individual output scripts into dish_common. Rather than deal with the complication this would create for CSV output, where there is only 1 timestamp field, just disallow the combination of options that could result in different timestamps (For CSV output only).
Fix an error case where poll loop counting was not being reset correctly.
Fix explicit --samples option to be honored when resuming from counter for history stats.
Probably not terribly useful unless someone needs to tunnel through a different network to get to their dish, but it makes testing the dish unreachable case a lot easier. This was complicated a bit by the fact that a channel (and therefor the dish IP and port) is needed to get the list of alert types via reflection due to prior changes.
This exposed some issues with the error message for dish unreachable, so fixed those.
This restores the functionality that the InfluxDB status polling script had whereby instead of using a new grpc Channel for each RPC call, it would keep one open and reuse it, retrying one time if it ever fails, which can happen if the connection is lost between calls. Now all the grpc scripts have this functionality.
Also, hedge a little bit in the descriptions for what the obstruction detail fields means, given that I'm not sure my assumptions there are correct.
Combined the history and status scripts for each data backend and moved some of the shared code into a separate module. Since the existing script names were not appropriate for the new combined versions, the main entry point scripts now have new names, which better conform with Python module name conventions: dish_grpc_text.py, dish_grpc_mqtt.py, and dish_grpc_influx.py. pylint seems happier with those names, at any rate.
Switched the argument parsing from getopt to argparse, since that better facilitates sharing the common bits. The whole command line interface is now different in that the selection of data groups to process must be made as required arg(s) rather than option flags, but for the most part, the scripts support choosing an arbitrary list of groups and will process them all.
Split the monster main() functions into a more reasonable set of functions.
Added new functions to starlink_grpc to support getting the status, which returns the data in a form similar to the history data functions. Reformatted the starlink_grpc module docstring to render better with pydoc. Also changed the way sequence data field names are reported so that the consuming scripts can name them correctly without resorting to hacky special casing based on specific field names. This would subtly break the old scripts that had been expecting the old naming, but those scripts are now gone.
The code is harder to follow now, IMO, but this should allow adding of new features and/or data backends without having to make the same change in 6 places as had been the case. To that end, dish_grpc_text now supports bulk history mode, since it was trivial to add once I had it implemented in order to support that feature for dish_grpc_influx.
