Was this page helpful?
AddressTranslator¶
policies/addressResolution~AddressTranslator()
WARNING: Currently only the MappingAddressTranslator is supported by our driver. Using any other address translator, including custom implementations, will result in an error.
Translates IP addresses received from Cassandra nodes into locally queryable addresses.
The driver auto-detects new Cassandra nodes added to the cluster through server
side pushed notifications and through checking the system tables. For each
node, the address received will correspond to the address set as
rpc_address in the node yaml file. In most case, this is the correct
address to use by the driver and that is what is used by default. However,
sometimes the addresses received through this mechanism will either not be
reachable directly by the driver or should not be the preferred address to use
to reach the node (for instance, the rpc_address set on Cassandra nodes
might be a private IP, but some clients may have to use a public IP, or
pass by a router to reach that node). This interface allows to deal with
such cases, by allowing to translate an address as sent by a Cassandra node
to another address to be used by the driver for connection.
Please note that the contact points addresses provided while creating the Client instance are not "translated", only IP address retrieve from or sent by Cassandra nodes to the driver are.
Constructor¶
new AddressTranslator()
Methods¶
translate(address, port, callback)
Translates a Cassandra rpc_address to another address if necessary.
Parameters:
| Name | Type | Description |
|---|---|---|
address |
String | the address of a node as returned by Cassandra. Note that if the |
port |
Number | The port number, as specified in the protocolOptions at Client instance creation (9042 by default). |
callback |
function | Callback to invoke with endpoint as first parameter.
The endpoint is an string composed of the IP address and the port number in the format |