Rename GRPCClient to ClientConnPool. This type appears to be more of a
conn pool than a client. The clients receive the connections from this
pool.
Reduce some dependencies by adjusting the interface baoundaries.
Remove the need to create a second slice of Servers, just to pick one and throw the rest away.
Unexport serverResolver, it is not used outside the package.
Use a RWMutex for ServerResolverBuilder, some locking is read-only.
Add more godoc.
* fix lessThanHalfTime
* get lock for CAProvider()
* make a var to relate both vars
* rename to getCAProviderWithLock
* move CertificateTimeDriftBuffer to agent/connect/ca
In an upcoming change we will need to pass a grpc.ClientConnPool from
BaseDeps into Server. While looking at that change I noticed all of the
existing consulOption fields are already on BaseDeps.
Instead of duplicating the fields, we can create a struct used by
agent/consul, and use that struct in BaseDeps. This allows us to pass
along dependencies without translating them into different
representations.
I also looked at moving all of BaseDeps in agent/consul, however that
created some circular imports. Resolving those cycles wouldn't be too
bad (it was only an error in agent/consul being imported from
cache-types), however this change seems a little better by starting to
introduce some structure to BaseDeps.
This change is also a small step in reducing the scope of Agent.
Also remove some constants that were only used by tests, and move the
relevant comment to where the live configuration is set.
Removed some validation from NewServer and NewClient, as these are not
really runtime errors. They would be code errors, which will cause a
panic anyway, so no reason to handle them specially here.
secondaryIntermediateCertRenewalWatch was using `retryLoopBackoff` to
renew the intermediate certificate. Once it entered the inner loop and
started `retryLoopBackoff` it would never leave that.
`retryLoopBackoffAbortOnSuccess` will return when renewing is
successful, like it was intended originally.
The nodeCheck slice was being used as the first arg in append, which in some cases will modify the array backing the slice. This would lead to service checks for other services in the wrong event.
Also refactor some things to reduce the arguments to functions.
Creating a new readTxn does not work because it will not see the newly created objects that are about to be committed. Instead use the active write Txn.
Whenever an upsert/deletion of a config entry happens, within the open
state store transaction we speculatively test compile all discovery
chains that may be affected by the pending modification to verify that
the write would not create an erroneous scenario (such as splitting
traffic to a subset that did not exist).
If a single discovery chain evaluation references two config entries
with the same kind and name in different namespaces then sometimes the
upsert/deletion would be falsely rejected. It does not appear as though
this bug would've let invalid writes through to the state store so the
correction does not require a cleanup phase.
This commit refactors the state store usage code to track unique service
name changes on transaction commit. This means we only need to lookup
usage entries when reading the information, as opposed to iterating over
a large number of service indices.
- Take into account a service instance's name being changed
- Do not iterate through entire list of service instances, we only care
about whether there is 0, 1, or more than 1.
We add a WriteTxn interface for use in updating the usage memdb table,
with the forward-looking prospect of incrementally converting other
functions to accept interfaces.
As well, we use the ReadTxn in new usage code, and as a side effect
convert a couple of existing functions to use that interface as well.
Using the newly provided state store methods, we periodically emit usage
metrics from the servers.
We decided to emit these metrics from all servers, not just the leader,
because that means we do not have to care about leader election flapping
causing metrics turbulence, and it seems reasonable for each server to
emit its own view of the state, even if they should always converge
rapidly.
