Golang State.AssignUnit方法代碼示例

// AddUnits starts n units of the given service using the specified placement
// directives to allocate the machines.
func AddUnits(st *state.State, svc *state.Service, n int, placement []*instance.Placement) ([]*state.Unit, error) {
	units := make([]*state.Unit, n)
	// Hard code for now till we implement a different approach.
	policy := state.AssignCleanEmpty
	// All units should have the same networks as the service.
	networks, err := svc.Networks()
	if err != nil {
		return nil, errors.Errorf("cannot get service %q networks", svc.Name())
	}
	// TODO what do we do if we fail half-way through this process?
	for i := 0; i < n; i++ {
		unit, err := svc.AddUnit()
		if err != nil {
			return nil, errors.Annotatef(err, "cannot add unit %d/%d to service %q", i+1, n, svc.Name())
		}
		// Are there still placement directives to use?
		if i > len(placement)-1 {
			if err := st.AssignUnit(unit, policy); err != nil {
				return nil, errors.Trace(err)
			}
			units[i] = unit
			continue
		}
		if err := st.AssignUnitWithPlacement(unit, placement[i], networks); err != nil {
			return nil, errors.Annotatef(err, "adding new machine to host unit %q", unit.Name())
		}
		units[i] = unit
	}
	return units, nil
}

// AddUnits starts n units of the given service and allocates machines
// to them as necessary.
func AddUnits(st *state.State, svc *state.Service, n int, machineIdSpec string) ([]*state.Unit, error) {
	units := make([]*state.Unit, n)
	// Hard code for now till we implement a different approach.
	policy := state.AssignCleanEmpty
	// All units should have the same networks as the service.
	networks, err := svc.Networks()
	if err != nil {
		return nil, fmt.Errorf("cannot get service %q networks: %v", svc.Name(), err)
	}
	// TODO what do we do if we fail half-way through this process?
	for i := 0; i < n; i++ {
		unit, err := svc.AddUnit()
		if err != nil {
			return nil, fmt.Errorf("cannot add unit %d/%d to service %q: %v", i+1, n, svc.Name(), err)
		}
		if machineIdSpec != "" {
			if n != 1 {
				return nil, fmt.Errorf("cannot add multiple units of service %q to a single machine", svc.Name())
			}
			// machineIdSpec may be an existing machine or container, eg 3/lxc/2
			// or a new container on a machine, eg lxc:3
			mid := machineIdSpec
			var containerType instance.ContainerType
			specParts := strings.SplitN(machineIdSpec, ":", 2)
			if len(specParts) > 1 {
				firstPart := specParts[0]
				var err error
				if containerType, err = instance.ParseContainerType(firstPart); err == nil {
					mid = specParts[1]
				} else {
					mid = machineIdSpec
				}
			}
			if !names.IsMachine(mid) {
				return nil, fmt.Errorf("invalid force machine id %q", mid)
			}
			var unitCons *constraints.Value
			unitCons, err = unit.Constraints()
			if err != nil {
				return nil, err
			}

			var err error
			var m *state.Machine
			// If a container is to be used, create it.
			if containerType != "" {
				// Create the new machine marked as dirty so that
				// nothing else will grab it before we assign the unit to it.
				template := state.MachineTemplate{
					Series:            unit.Series(),
					Jobs:              []state.MachineJob{state.JobHostUnits},
					Dirty:             true,
					Constraints:       *unitCons,
					RequestedNetworks: networks,
				}
				m, err = st.AddMachineInsideMachine(template, mid, containerType)
			} else {
				m, err = st.Machine(mid)
			}
			if err != nil {
				return nil, fmt.Errorf("cannot assign unit %q to machine: %v", unit.Name(), err)
			}
			err = unit.AssignToMachine(m)

			if err != nil {
				return nil, err
			}
		} else if err := st.AssignUnit(unit, policy); err != nil {
			return nil, err
		}
		units[i] = unit
	}
	return units, nil
}