Retrieves the log file for the role's main process.
If the role is not started, this will be the log file associated with the last time the role was run.
Log files are returned as plain text (type "text/plain").
|clusterName||The name of the cluster.||path|
|serviceName||The service to which the role belongs.||path|
|roleName||The role to start.||path|
Contents of the role's log file.