This continues the work done in #14908 where a crude solution to prevent a
goroutine leak was implemented. The former code would launch a perpetual
goroutine family every iteration (+1 +1) and the fixed code simply caused a
new goroutine family to first cancel the prior one to prevent the
leak (-1 +1 == 0).
This PR refactors this code completely to:
- make it more understandable
- remove the recursion-via-goroutine strangeness
- prevent unnecessary RPC fetches when the prior one has errored.
The core issue arose from a conflation of the entry.Fetching field to mean:
- there is an RPC (blocking query) in flight right now
- there is a goroutine running to manage the RPC fetch retry loop
The problem is that the goroutine-leak-avoidance check would treat
Fetching like (2), but within the body of a goroutine it would flip that
boolean back to false before the retry sleep. This would cause a new
chain of goroutines to launch which #14908 would correct crudely.
The refactored code uses a plain for-loop and changes the semantics
to track state for "is there a goroutine associated with this cache entry"
instead of the former.
We use a uint64 unique identity per goroutine instead of a boolean so
that any orphaned goroutines can tell when they've been replaced when
the expiry loop deletes a cache entry while the goroutine is still running
and is later replaced.
To support Destinations on the service-defaults (for tproxy with terminating gateway), we need to now also make servers watch service-defaults config entries.
The `lib/startup`-addon is used to create a custom
index.html page to boot up the app. Because this is
a custom approach and we aren't relying on setting
rootURL to a different value when running the app
in `production` we need to set `publicAssetURL`
in the configuration we pass to `ember-auto-import`.
Reference:
9a2887f1d0/docs/upgrade-guide-2.0.md (quick-summary)
Previously, I would sometimes get Killed errors when executing the
binary created by `make dev`. This is because we were using `cp`
and OSX has a bug where it caches the old signature and so doesn't
allow the new binary to run (see https://apple.stackexchange.com/a/428388)
This commit updates the establish endpoint to bubble up a 403 status
code to callers when the establishment secret from the token is invalid.
This is a signal that a new peering token must be generated.
R.B. Boyer