* test(storage): ensure multiple engines can run concurrently
* feat(storage): expose control over retention run
Fixes#15134.
This commit adds the ability to inject a functional option into a
storage.Engine for controlling when the retention enforcer can run.
Previously, retention enforcers ran on an interval; if you ran multiple
storage engines (as we do in some environments) then it was not possible
to coordinate when engines ran retention. Often they would synchronise
because they started at the same time.
This change will let you specify a blocking function to control when the
retention enforcer can run.
A simple function for serialising retention enforcement across multiple
storage engines could look like:
```go
var mu sync.Mutex
func f() (done func()) {
mu.Lock()
return func() { mu.Unlock() }
}
```
I did this with a dumb editor macro, so some comments changed too.
Also rename root package from platform to influxdb.
In interest of minimizing risk, anyone importing the root package has
now aliased it to "platform" so that no changes beyond imports were
necessary in those files.
Lastly, replace the old platform module to local path /dev/null so that
nobody can accidentally reintroduce a platform dependency while
migrating platform code to influxdb.
Edd Robinson
Edd Robinson
Jacob Marble
tmgordeeva
Kelvin Wang
Jeff Wendling
Mark Rushakoff
Chris Goller