Description
The ConnectionResolver class is used to retrieve component connections.
Important points
- If the connections are configured to be retrieved from IDiscovery, the connection resolver will automatically locate IDiscovery in component references and retrieve the connections from there using the discovery_key parameter.
Configuration parameters
connection:
- discovery_key: (optional) a key to retrieve the connection from IDiscovery
- … : other connection parameters
connections: alternative to connection
- [connection params 1]: first connection parameters
- … : connection parameters for key 1
- [connection params N]: Nth connection parameters
- … : connection parameters for key N
References
- *:discovery:*:*:1.0 - (optional) IDiscovery services to resolve connections
Constructors
Creates a new instance of connection resolver.
public
ConnectionResolver(ConfigParams config, IReferences references)
- config: ConfigParams - (optional) component configuration parameters
- references: IReferences - (optional) component references
Instance methods
add
Adds a new connection to component connections
public
void add(ConnectionParams connection)
- connection: ConnectionParams - new connection parameters to be added
configure
Configures component by passing configuration parameters.
public
void configure(ConfigParams config)
- config: ConfigParams - configuration parameters to be set.
getAll
Gets all connections configured in component configuration. Redirect to Discovery services is not done at this point. If you need fully fleshed connection use resolve method instead.
public
List<ConnectionParams> getAll()
- returns: List<ConnectionParams> - a list with connection parameters
register
Registers the given connection in all referenced discovery services. This method can be used for dynamic service discovery.
public
void register(IContext context, ConnectionParams connection) throws ApplicationException
- context: IContext - (optional) a context to trace execution through call chain.
- connection: ConnectionParams - a connection to register.
resolve
Resolves a single component connection. If connections are configured to be retrieved from Discovery service it finds a IDiscovery and resolves the connection there.
public
ConnectionParams resolve(IContext context) throws ApplicationException
- context: IContext - (optional) a context to trace execution through call chain.
- returns: ConnectionParams - resolved connection parameters or null if nothing was found.
resolveAll
Resolves all component connection. If connections are configured to be retrieved from Discovery service it finds a IDiscovery and resolves the connection there.
public
ListresolveAll(IContext context) throws ApplicationException
- context: IContext - (optional) a context to trace execution through call chain.
- returns: Promise<ConnectionParams[]> - a list of resolved connections.
setReferences
Sets references to dependent components.
public
void setReferences(IReferences references)
- references: IReferences - references to locate the component dependencies.
Examples
{
ConfigParams config = ConfigParams.fromTuples(
"connection.host", "10.1.1.100",
"connection.port", 8080
);
ConnectionResolver connectionResolver = new ConnectionResolver();
connectionResolver.configure(config);
connectionResolver.setReferences(references);
connectionResolver.resolve("123");
}