Golang RangeAllocation.Range方法代碼示例

// Snapshot saves the current state of the pool.
func (r *PortAllocator) Snapshot(dst *api.RangeAllocation) error {
	snapshottable, ok := r.alloc.(allocator.Snapshottable)
	if !ok {
		return fmt.Errorf("not a snapshottable allocator")
	}
	rangeString, data := snapshottable.Snapshot()
	dst.Range = rangeString
	dst.Data = data
	return nil
}

// runOnce verifies the state of the port allocations and returns an error if an unrecoverable problem occurs.
func (c *Repair) runOnce() error {
	// TODO: (per smarterclayton) if Get() or ListServices() is a weak consistency read,
	// or if they are executed against different leaders,
	// the ordering guarantee required to ensure no port is allocated twice is violated.
	// ListServices must return a ResourceVersion higher than the etcd index Get triggers,
	// and the release code must not release services that have had ports allocated but not yet been created
	// See #8295

	// If etcd server is not running we should wait for some time and fail only then. This is particularly
	// important when we start apiserver and etcd at the same time.
	var snapshot *api.RangeAllocation

	err := wait.PollImmediate(time.Second, 10*time.Second, func() (bool, error) {
		var err error
		snapshot, err = c.alloc.Get()
		return err == nil, err
	})
	if err != nil {
		return fmt.Errorf("unable to refresh the port allocations: %v", err)
	}
	// If not yet initialized.
	if snapshot.Range == "" {
		snapshot.Range = c.portRange.String()
	}
	// Create an allocator because it is easy to use.
	stored, err := portallocator.NewFromSnapshot(snapshot)
	if err != nil {
		return fmt.Errorf("unable to rebuild allocator from snapshot: %v", err)
	}

	// We explicitly send no resource version, since the resource version
	// of 'snapshot' is from a different collection, it's not comparable to
	// the service collection. The caching layer keeps per-collection RVs,
	// and this is proper, since in theory the collections could be hosted
	// in separate etcd (or even non-etcd) instances.
	list, err := c.serviceClient.Services(api.NamespaceAll).List(api.ListOptions{})
	if err != nil {
		return fmt.Errorf("unable to refresh the port block: %v", err)
	}

	rebuilt := portallocator.NewPortAllocator(c.portRange)
	// Check every Service's ports, and rebuild the state as we think it should be.
	for i := range list.Items {
		svc := &list.Items[i]
		ports := service.CollectServiceNodePorts(svc)
		if len(ports) == 0 {
			continue
		}

		for _, port := range ports {
			switch err := rebuilt.Allocate(port); err {
			case nil:
				if stored.Has(port) {
					// remove it from the old set, so we can find leaks
					stored.Release(port)
				} else {
					// doesn't seem to be allocated
					runtime.HandleError(fmt.Errorf("the node port %d for service %s/%s is not allocated; repairing", port, svc.Name, svc.Namespace))
				}
				delete(c.leaks, port) // it is used, so it can't be leaked
			case portallocator.ErrAllocated:
				// TODO: send event
				// port is duplicate, reallocate
				runtime.HandleError(fmt.Errorf("the node port %d for service %s/%s was assigned to multiple services; please recreate", port, svc.Name, svc.Namespace))
			case err.(*portallocator.ErrNotInRange):
				// TODO: send event
				// port is out of range, reallocate
				runtime.HandleError(fmt.Errorf("the port %d for service %s/%s is not within the port range %v; please recreate", port, svc.Name, svc.Namespace, c.portRange))
			case portallocator.ErrFull:
				// TODO: send event
				// somehow we are out of ports
				return fmt.Errorf("the port range %v is full; you must widen the port range in order to create new services", c.portRange)
			default:
				return fmt.Errorf("unable to allocate port %d for service %s/%s due to an unknown error, exiting: %v", port, svc.Name, svc.Namespace, err)
			}
		}
	}

	// Check for ports that are left in the old set.  They appear to have been leaked.
	stored.ForEach(func(port int) {
		count, found := c.leaks[port]
		switch {
		case !found:
			// flag it to be cleaned up after any races (hopefully) are gone
			runtime.HandleError(fmt.Errorf("the node port %d may have leaked: flagging for later clean up", port))
			count = numRepairsBeforeLeakCleanup - 1
			fallthrough
		case count > 0:
			// pretend it is still in use until count expires
			c.leaks[port] = count - 1
			if err := rebuilt.Allocate(port); err != nil {
				runtime.HandleError(fmt.Errorf("the node port %d may have leaked, but can not be allocated: %v", port, err))
			}
		default:
			// do not add it to the rebuilt set, which means it will be available for reuse
			runtime.HandleError(fmt.Errorf("the node port %d appears to have leaked: cleaning up", port))
		}
	})

//.........這裏部分代碼省略.........