This patch decouples the local state and the anti-entropy code from the
agent and from each other to have cleaner separation of concerns and to
ensure that data structures are properly locked.
The anti-entropy tests relied on the side-effect of the StartSync()
method to perform a full sync instead of a partial sync. This lead to
multiple anti-entropy go routines being started unnecessary retry loops.
This change changes the behavior to perform synchronous full syncs when
necessary removing the need for all of the time.Sleep and most of the
retry loops.
The state of the service and health check records was spread out over
multiple maps guarded by a single lock. Access to the maps has to happen
in a coordinated effort and the tests often violated this which made
them brittle and racy.
This patch replaces the multiple maps with a single one for both checks
and services to make the code less fragile.
This is also necessary since moving the local state into its own package
creates circular dependencies for the tests. To avoid this the tests can
no longer access internal data structures which they should not be doing
in the first place.
The tests still don't compile but this is a ncessary step in that
direction.
The anti-entropy code manages background synchronizations of the local
state on a regular basis or on demand when either the state has changed
or a new consul server has been added.
This patch moves the anti-entropy code into its own package and
decouples it from the local state code since they are performing
two different functions.
To simplify code-review this revision does not make any optimizations,
renames or refactorings. This will happen in subsequent commits.
The `consul agent` command was ignoring extra command line arguments
which can lead to confusion when the user has for example forgotten to
add a dash in front of an argument or is not using an `=` when setting
boolean flags to `true`. `-bootstrap true` is not the same as
`-bootstrap=true`, for example.
Since all command line flags are known and we don't expect unparsed
arguments we can return an error. However, this may make it slightly
more difficult in the future if we ever wanted to have these kinds of
arguments.
Fixes#3397
DNS recursors can be added through go-sockaddr templates. Entries
are deduplicated while the order is maintained.
Originally proposed by @taylorchu
See #2932
Frank Schroeder