brooklyn.location.MachineProvisioningLocation Maven / Gradle / Ivy
package brooklyn.location;
import java.util.Collection;
import java.util.Map;
/**
* A location that is able to provision new machines within its location.
*
* This interface extends {@link Location} to add the ability to provision {@link MachineLocation}s in this location.
*/
public interface MachineProvisioningLocation extends Location {
/**
* Obtain a machine in this location.
*
* @param flags Details of the desired machine (e.g. image, size, open ports, etc; some flag support is limited to selected providers).
* "callerContext" can be specified to have custom logging and error messages (useful if starting machines in parallel)
* @return a machine that is a child of this location.
* @throws NoMachinesAvailableException if there are no machines available in this location (or impls may return null, but that is discouraged)
*/
T obtain(Map flags) throws NoMachinesAvailableException;
/**
* Creates a new location of the same type, but with additional creation instructions in the form of flags,
* e.g. for specifying subnets, security groups, etc
*
* Implementers who wish to subclass this provisioning location for additional functionality
* in a specific cloud can use the relevant implementation of this method as a guide.
*/
MachineProvisioningLocation newSubLocation(Map newFlags);
/**
* Release a previously-obtained machine.
*
* @param machine a {@link MachineLocation} previously obtained from a call to {@link #obtain()}
* @throws IllegalStateException if the machine did not come from a call to {@link #obtain()} or it has already been released.
*/
void release(T machine);
/**
* Gets flags, suitable as an argument to {@link #obtain(Map)}. The tags provided give
* hints about the machine required. The provisioning-location could be configured to
* understand those tags.
*
* For example, an AWS-location could be configured to understand that a particular entity
* type (e.g. "TomcatServer") requires a particular AMI in that region, so would return the
* required image id.
*
* @param tags
* @return
*/
Map getProvisioningFlags(Collection tags);
}