Extend Consul’s intentions model to allow for request-based access control enforcement for HTTP-like protocols in addition to the existing connection-based enforcement for unspecified protocols (e.g. tcp).
- Upgrade the ConfigEntry.ListAll RPC to be kind-aware so that older
copies of consul will not see new config entries it doesn't understand
replicate down.
- Add shim conversion code so that the old API/CLI method of interacting
with intentions will continue to work so long as none of these are
edited via config entry endpoints. Almost all of the read-only APIs will
continue to function indefinitely.
- Add new APIs that operate on individual intentions without IDs so that
the UI doesn't need to implement CAS operations.
- Add a new serf feature flag indicating support for
intentions-as-config-entries.
- The old line-item intentions way of interacting with the state store
will transparently flip between the legacy memdb table and the config
entry representations so that readers will never see a hiccup during
migration where the results are incomplete. It uses a piece of system
metadata to control the flip.
- The primary datacenter will begin migrating intentions into config
entries on startup once all servers in the datacenter are on a version
of Consul with the intentions-as-config-entries feature flag. When it is
complete the old state store representations will be cleared. We also
record a piece of system metadata indicating this has occurred. We use
this metadata to skip ALL of this code the next time the leader starts
up.
- The secondary datacenters continue to run the old intentions
replicator until all servers in the secondary DC and primary DC support
intentions-as-config-entries (via serf flag). Once this condition it met
the old intentions replicator ceases.
- The secondary datacenters replicate the new config entries as they are
migrated in the primary. When they detect that the primary has zeroed
it's old state store table it waits until all config entries up to that
point are replicated and then zeroes its own copy of the old state store
table. We also record a piece of system metadata indicating this has
occurred. We use this metadata to skip ALL of this code the next time
the leader starts up.
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.