adapt to JSON changes (January 2022)

[dneuge]

New additions noticed in January 2022:

• v3 Data File:
  • Flight Plans:
  • assigned_transponder (string), default 0000?
  • FSD Servers:
  • client_connections_allowed (bool)
  • is_sweatbox (bool)
• JSON Network Status:
  • in data:
  • servers_sweatbox
  • servers_all

Check if support for data.servers has been added at some point to this parser.

These changes were not publically announced (again). API documentation seems to be offline (would be located at https://api.vatsim.dev/#operation/DataServerV3)

[dneuge]

New fields are now available via Client#getAssignedTransponderCodeDecimal() and FSDServer#isSweatbox().

client_connections_allowed is a weird one. The previous field clients_connection_allowed (note the swapped plural) was "always" there (same as on legacy format) and never observed with any different value than 1, so I already assumed that it's probably a boolean encoded as an integer (and offlined servers simply are never exposed through the data files). According to my code comments, JSON v3 API documentation (still offline...) stated that the old field is int32. parseClientConnectionAllowedInteger translated 0 to false and all other values to true (as would be the case when comparing an integer on low-level languages or machine code) but logged a warning (via SLF4J, not parser log) in case we encounter some other value. With the new field I added an additional check which reports any mismatch between the two fields to the parser log but ultimately trusts the boolean (because the boolean indication isClientConnectionAllowed is what our FSDServer class was always supposed to transport, not an integer). Let's see if we ever hit that message; I suspect the old field is simply cargo cult from migrating the legacy formats to JSON and might be deleted in a future JSON format version.

Nothing needed to be done to support servers_sweatbox and servers_all on NetworkInformation. Any key on data will be transported. Whoever needs that data can already access it using getDataUrls or getAllUrlsByDataKey.