* Replace usage of `discover::Change` with a tuple
Remove the assumption that a `Remove` variant would never be created
with type changes that allow the compiler to guarantee that assumption.
* Add a `version` field to the `Client` type
Keep track of the peer's reported protocol version.
* Create `LoadTrackedClient` type
A `peer::Client` type wrapper that implements `Load`. This helps with
the creation of a client service that has extra peer information to be
accessed without having to send requests.
* Use `LoadTrackedClient` in `initialize`
Ensure that `PeerSet` receives `LoadTrackedClient`s so that it will be
able to query the peer's protocol version later on.
* Require `LoadTrackedClient` in `PeerSet`
Replace the generic type with a concrete `LoadTrackedClient` so that we
can query its version.
* Create `MinimumPeerVersion` helper type
A type to track the current minimum protocol version for connected
peers based on the current block height.
* Use `MinimumPeerVersion` in handshakes
Keep the code to obtain the current minimum peer protocol version in a
central place.
* Add a `MinimumPeerVersion` instance to `PeerSet`
Prepare it to be able to disconnect from outdated peers based on the
current minimum supported peer protocol version.
* Disconnect from ready services for outdated peers
When the minimum peer protocol version is detected to have changed
(because of a network upgrade), remove all ready services of peers that
became outdated.
* Cancel added unready services of outdated peers
Only add an unready service if it's for a peer that has a supported
protocol version. Otherwise, add it but drop the cancel handle so that
the `UnreadyService` can execute and detect that it was cancelled.
* Avoid adding ready services for outdated peers
If a service becomes ready but it's for a connection to an outdated
peer, drop it.
* Improve comment inside `crawl_and_dial`
Describe an edge case that is also handled but was not explicit.
Co-authored-by: teor <teor@riseup.net>
* Test if calculated minimum peer version is correct
Given an arbitrary best chain tip height, check that the calculated
minimum peer protocol version is the expected value.
* Test if minimum version changes with chain tip
Apply an arbitrary list of chain tip height updates and check that for
each update the minimum peer version is calculated correctly.
* Test minimum peer version changed reports
Simulate a series of best chain tip height updates, and check for
minimum peer version updates at least once between them. Changes should
only be reported once.
* Create a `MockedClientHandle` helper type
Used to create and then track a mock `Client` instance.
* Add `MinimumPeerVersion::with_mock_chain_tip`
An extension method useful for tests, that contains some shared
boilerplate code.
* Bias arbitrary `Version`s to be in valid range
Give a 50% chance for an arbitrary `Version` to be in the range of
previously used values the Zcash network.
* Create a `PeerVersions` helper type
Helps with the creation of mocked client services with arbitrary
protocol versions.
* Create a `PeerSetGuard` helper type
An auxiliary type to a `PeerSet` instance created for testing. It keeps
track of any dummy endpoints of channels created and passed to the
`PeerSet` instance.
* Create a `PeerSetBuilder` helper type
Helps to reduce the code when preparing a `PeerSet` test instance.
* Test if outdated peers are rejected by `PeerSet`
Simulate a set of discovered peers being sent to the `PeerSet`. Ensure
that only up-to-date peers are kept by the `PeerSet` and that outdated
peers are dropped.
* Create `BlockHeightPairAcrossNetworkUpgrades` type
A helper type that allows the creation of arbitrary block height pairs,
where one value is before and the other is at or after the activation
height of an arbitrary network upgrade.
* Test if peers are dropped as they become outdated
Simulate a network upgrade, and check that peers that become outdated
are dropped by the `PeerSet`.
* Remove dbg! macros
Co-authored-by: teor <teor@riseup.net>