Make auto-bounds calc non-default

[nyurik]

It seems the automatic bbox boundary computation is frequently causes slowdowns on startup, and confusion among novice users. I personally also experienced it. Let's make bounds computation disabled by default.

Changes

• Add a new --bounds enum config option with values none (default) and auto. TBD: Should it be full, world, all or planet instead of none?
• Remove --disable_bounds option, or at least make it deprecated for now, and prevent its usage at the same time as --bounds
• Config should also support the same values, e.g. bounds: auto in addition to bounds: [-180,-90,180,90]
• Config should obsolete the disabled_bounds and instead add a bounds value to the auto_publish.tables section - from PgConfig to PgCfgPublishType
  • I think we should also move default_srid, max_feature_count to the auto_publish.tables section.

To consider

It might be good to do asynchronous bounds computation, where it gets done after Martin startup, and initially Martin uses full bounds until the computation is done... This might be a lot trickier though, because we will need to modify how all sources are stored and updated. At the moment, all sources are immutable and exist for the entire duration of the program, but this may change as part of the source auto-refresh work (ability to re-query the database to add new sources on the fly #288)

See also:

• Docker: can't reach Martin server #954
• Log a warning if PG startup takes too long #810
• Log a warning if PG startup takes too long #924

[nyurik]

See implementation ^, some changes from the initial proposal, and on the second thought I don't think moving it to auto-publish makes sense