diff options
Diffstat (limited to 'node/service.go')
| -rw-r--r-- | node/service.go | 35 |
1 files changed, 29 insertions, 6 deletions
diff --git a/node/service.go b/node/service.go index ec838dbe8..28fc34764 100644 --- a/node/service.go +++ b/node/service.go @@ -18,6 +18,7 @@ package node import ( "path/filepath" + "reflect" "github.com/ethereum/go-ethereum/ethdb" "github.com/ethereum/go-ethereum/event" @@ -28,18 +29,39 @@ import ( // the protocol stack, that is passed to all constructors to be optionally used; // as well as utility methods to operate on the service environment. type ServiceContext struct { - dataDir string // Data directory for protocol persistence - EventMux *event.TypeMux // Event multiplexer used for decoupled notifications + datadir string // Data directory for protocol persistence + services map[string]Service // Index of the already constructed services + EventMux *event.TypeMux // Event multiplexer used for decoupled notifications } // Database opens an existing database with the given name (or creates one if no // previous can be found) from within the node's data directory. If the node is // an ephemeral one, a memory database is returned. func (ctx *ServiceContext) Database(name string, cache int) (ethdb.Database, error) { - if ctx.dataDir == "" { + if ctx.datadir == "" { return ethdb.NewMemDatabase() } - return ethdb.NewLDBDatabase(filepath.Join(ctx.dataDir, name), cache) + return ethdb.NewLDBDatabase(filepath.Join(ctx.datadir, name), cache) +} + +// Service retrieves an already constructed service registered under a given id. +func (ctx *ServiceContext) Service(id string) Service { + return ctx.services[id] +} + +// SingletonService retrieves an already constructed service using a specific type +// implementing the Service interface. This is a utility function for scenarios +// where it is known that only one instance of a given service type is running, +// allowing to access services without needing to know their specific id with +// which they were registered. +func (ctx *ServiceContext) SingletonService(service interface{}) (string, error) { + for id, running := range ctx.services { + if reflect.TypeOf(running) == reflect.ValueOf(service).Elem().Type() { + reflect.ValueOf(service).Elem().Set(reflect.ValueOf(running)) + return id, nil + } + } + return "", ErrServiceUnknown } // ServiceConstructor is the function signature of the constructors needed to be @@ -58,8 +80,9 @@ type Service interface { // Protocol retrieves the P2P protocols the service wishes to start. Protocols() []p2p.Protocol - // Start spawns any goroutines required by the service. - Start() error + // Start is called after all services have been constructed and the networking + // layer was also initialized to spawn any goroutines required by the service. + Start(server *p2p.Server) error // Stop terminates all goroutines belonging to the service, blocking until they // are all terminated. |