This adds a new very tiny memdb table and corresponding raft operation
for updating a very small effective map[string]string collection of
"system metadata". This can persistently record a fact about the Consul
state machine itself.
The first use of this feature will come in a later PR.
This new package provides a client agent implementation of an interface
for fetching the health of services.
This approach has a number of benefits:
1. It provides a much more explicit interface. Instead of everything
dependency on `RPC()` and `Cache.Get()` for many unrelated things
they can depend on a type that are named according to the behaviour
it provides.
2. It gives us a single place to vary the behaviour and migrate to
a new form of RPC (gRPC). The current implementation has two options
(cache, or direct RPC), and in the future we will have more.
It is also a great opporunity to start adding `context.Context` args
to these operations, which in the future will allow us to cancel
the operations.
3. As a concequence of the first, in the Server agent where we make
these calls we can replace the current in-memory RPC calls with
a thin adapter for the real method. This removes the `net/rpc`
machinery from the call in places where it is not needed.
This new package is quite small right now, but I think we can expect it
to grow to a more reasonable size as other RPC calls are replaced.
This change also happens to replace two very similar implementations with
a single implementation.
Reduce Jitter to one function
Rename NewRetryWaiter
Fix a bug in calculateWait where maxWait was applied before jitter, which would make it
possible to wait longer than maxWait.
This really only matters for unit tests, since typically if an agent shuts down its server, it follows that up by exiting the process, which would also clean up all of the networking anyway.
The subscribe endpoint needs to be able to inspect the payload to filter
events, and convert them into the protobuf types.
Use the protobuf CatalogOp type for the operation field, for now. In the
future if we end up with multiple interfaces we should be able to remove
the protobuf dependency by changing this to an int32 and adding a test
for the mapping between the values.
Make the value of the payload a concrete type instead of interface{}. We
can create other payloads for other event types.
The router.Manager is already rebalancing servers for other connection pools, so it can call into our resolver to do the same.
This change allows us to remove the serf dependency from resolverBuilder, and remove Datacenter from the config.
Also revert the change to refreshServerRebalanceTimer
It only needs to be refereced from the Router, because there is only 1 instance, and the
Router can call AddServer/RemoveServer like it does on the Manager.
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.
When calling `GetDatacentersByDistance()` or `GetDatacentersMap()`, an
incorrect condition was used to diplay log message, thus flooding
Consul's logs.
Example of message:
```
[WARN] agent.router: Non-server in server-only area: non_server=myClientNode area=lan
```
This message is only valid for WAN areas, filter to avoid creating
hundreds of logs/s on our clusters, each time someone is calling this
method.
Our logs were flooded by such messages when migrating our Consul servers
from 1.7.7 to 1.8.4.
This will issue fix#8663
Occasionally this test would flake. The flakes were fixed by:
1. Stopping the service and retrying to check on metrics. This way we
also include the active_streams going to 0 in the metric calls.
2. Using a reference to the global Metrics. This way when other tests
have background goroutines that are still shutting down, they won't
emit metrics to the metric instance with the fake Sink. The stats
test can patch the local reference to the global, so the existing
statHandlers will continue to emit to the global, but the stats
test will send all metrics to the replacement.
https server.
In #8234 I changed a few tests to use TestAgent.HTTPAddr() to find the
addr used in the test. Due to the way HTTPAddr() was implemented these
tests were passing, but I think the pass was incidental. HTTPAddr() was
not matching any servers, and was instead returning the last server,
which happened to be the one these tests wanted.
This commit fixes the implementation of HTTPAddr to panic if no match
was found. The tests which require an HTTPS server are changed to use
a new firstAddr() to look up the correct address.
Daniel Nephin