net.corda.core.node.services / NetworkMapCache

# NetworkMapCache

`interface NetworkMapCache`

A network map contains lists of nodes on the network along with information about their identity keys, services they provide and host names or IP addresses where they can be connected to. The cache wraps around a map fetched from an authoritative service, and adds easy lookup of the data stored within it. Generally it would be initialised with a specified network map service, which it fetches data from and then subscribes to updates of.

### Types

MapChange | `data class MapChange`
MapChangeType | `enum class MapChangeType`

### Properties

changed | `abstract val changed: <ERROR CLASS><MapChange>` Tracks changes to the network map cache
mapServiceRegistered | `abstract val mapServiceRegistered: <ERROR CLASS><Unit>` Future to track completion of the NetworkMapService registration.
networkMapNodes | `abstract val networkMapNodes: List<NodeInfo>` A list of nodes that advertise a network map service
notaryNodes | `abstract val notaryNodes: List<NodeInfo>` A list of nodes that advertise a notary service
partyNodes | `abstract val partyNodes: List<NodeInfo>` A list of all nodes the cache is aware of
regulators | `abstract val regulators: List<NodeInfo>` A list of nodes that advertise a regulatory service. Identifying the correct regulator for a trade is outside the scope of the network map service, and this is intended solely as a sanity check on configuration stored elsewhere.

### Functions

addMapService | `abstract fun addMapService(net: MessagingService, networkMapAddress: SingleMessageRecipient, subscribe: Boolean, ifChangedSinceVer: Int? = null): <ERROR CLASS><Unit>` Add a network map service; fetches a copy of the latest map from the service and subscribes to any further updates.
addNode | `abstract fun addNode(node: NodeInfo): Unit` Adds a node to the local cache (generally only used for adding ourselves).
deregisterForUpdates | `abstract fun deregisterForUpdates(net: MessagingService, service: NodeInfo): <ERROR CLASS><Unit>` Deregister from updates from the given map service.
get | `abstract fun get(): Collection<NodeInfo>` Get a copy of all nodes in the map. `abstract fun get(serviceType: ServiceType): Collection<NodeInfo>` Get the collection of nodes which advertise a specific service.
getAnyNotary | `abstract fun getAnyNotary(type: ServiceType? = null): Party?` Returns a notary identity advertised by any of the nodes on the network (chosen at random)
getNodeByCompositeKey | `abstract fun getNodeByCompositeKey(compositeKey: CompositeKey): NodeInfo?` Look up the node info for a composite key.
getNodeByLegalName | `abstract fun getNodeByLegalName(name: String): NodeInfo?` Look up the node info for a legal name.
getNotary | `abstract fun getNotary(name: String): Party?` Gets a notary identity by the given name.
getRecommended | `abstract fun getRecommended(type: ServiceType, contract: Contract, vararg party: Party): NodeInfo?` Get a recommended node that advertises a service, and is suitable for the specified contract and parties. Implementations might understand, for example, the correct regulator to use for specific contracts/parties, or the appropriate oracle for a contract.
getRepresentativeNode | `abstract fun getRepresentativeNode(party: Party): NodeInfo?` Given a party, returns a node advertising it as an identity. If more than one node found the result is chosen at random.
isNotary | `abstract fun isNotary(party: Party): Boolean` Checks whether a given party is an advertised notary identity
removeNode | `abstract fun removeNode(node: NodeInfo): Unit` Removes a node from the local cache.
runWithoutMapService | `abstract fun runWithoutMapService(): Unit` For testing where the network map cache is manipulated marks the service as immediately ready.
track | `abstract fun track(): <ERROR CLASS><List<NodeInfo>, <ERROR CLASS><MapChange>>` Atomically get the current party nodes and a stream of updates. Note that the Observable buffers updates until the first subscriber is registered so as to avoid racing with early updates.

### Companion Object Properties

logger | `val logger: <ERROR CLASS>`

### Inheritors

InMemoryNetworkMapCache | `open class InMemoryNetworkMapCache : SingletonSerializeAsToken, NetworkMapCache` Extremely simple in-memory cache of the network map.