dotcloud/docker

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daemon/cluster/networks.go

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package cluster // import "github.com/docker/docker/daemon/cluster"

import (
    "context"
    "fmt"

    "github.com/containerd/log"
    "github.com/docker/docker/api/types/filters"
    "github.com/docker/docker/api/types/network"
    types "github.com/docker/docker/api/types/swarm"
    "github.com/docker/docker/daemon/cluster/convert"
    networkSettings "github.com/docker/docker/daemon/network"
    "github.com/docker/docker/errdefs"
    swarmapi "github.com/moby/swarmkit/v2/api"
    "github.com/pkg/errors"
)

// GetNetworks returns all current cluster managed networks.
func (c *Cluster) GetNetworks(filter filters.Args) ([]network.Inspect, error) {
    var f *swarmapi.ListNetworksRequest_Filters

    if filter.Len() > 0 {
        f = &swarmapi.ListNetworksRequest_Filters{}

        if filter.Contains("name") {
            f.Names = filter.Get("name")
            f.NamePrefixes = filter.Get("name")
        }

        if filter.Contains("id") {
            f.IDPrefixes = filter.Get("id")
        }
    }

    list, err := c.getNetworks(f)
    if err != nil {
        return nil, err
    }
    filterPredefinedNetworks(&list)

    return networkSettings.FilterNetworks(list, filter)
}

func filterPredefinedNetworks(networks *[]network.Inspect) {
    if networks == nil {
        return
    }
    var idxs []int
    for i, nw := range *networks {
        if v, ok := nw.Labels["com.docker.swarm.predefined"]; ok && v == "true" {
            idxs = append(idxs, i)
        }
    }
    for i, idx := range idxs {
        idx -= i
        *networks = append((*networks)[:idx], (*networks)[idx+1:]...)
    }
}

func (c *Cluster) getNetworks(filters *swarmapi.ListNetworksRequest_Filters) ([]network.Inspect, error) {
    c.mu.RLock()
    defer c.mu.RUnlock()

    state := c.currentNodeState()
    if !state.IsActiveManager() {
        return nil, c.errNoManager(state)
    }

    ctx := context.TODO()
    ctx, cancel := context.WithTimeout(ctx, swarmRequestTimeout)
    defer cancel()

    r, err := state.controlClient.ListNetworks(ctx, &swarmapi.ListNetworksRequest{Filters: filters})
    if err != nil {
        return nil, err
    }

    networks := make([]network.Inspect, 0, len(r.Networks))

    for _, nw := range r.Networks {
        networks = append(networks, convert.BasicNetworkFromGRPC(*nw))
    }

    return networks, nil
}

// GetNetwork returns a cluster network by an ID.
func (c *Cluster) GetNetwork(input string) (network.Inspect, error) {
    var nw *swarmapi.Network

    if err := c.lockedManagerAction(func(ctx context.Context, state nodeState) error {
        n, err := getNetwork(ctx, state.controlClient, input)
        if err != nil {
            return err
        }
        nw = n
        return nil
    }); err != nil {
        return network.Inspect{}, err
    }
    return convert.BasicNetworkFromGRPC(*nw), nil
}

// GetNetworksByName returns cluster managed networks by name.
// It is ok to have multiple networks here. #18864
func (c *Cluster) GetNetworksByName(name string) ([]network.Inspect, error) {
    // Note that swarmapi.GetNetworkRequest.Name is not functional.
    // So we cannot just use that with c.GetNetwork.
    return c.getNetworks(&swarmapi.ListNetworksRequest_Filters{
        Names: []string{name},
    })
}

func attacherKey(target, containerID string) string {
    return containerID + ":" + target
}

// UpdateAttachment signals the attachment config to the attachment
// waiter who is trying to start or attach the container to the
// network.
func (c *Cluster) UpdateAttachment(target, containerID string, config *network.NetworkingConfig) error {
    c.mu.Lock()
    attacher, ok := c.attachers[attacherKey(target, containerID)]
    if !ok || attacher == nil {
        c.mu.Unlock()
        return fmt.Errorf("could not find attacher for container %s to network %s", containerID, target)
    }
    if attacher.inProgress {
        log.G(context.TODO()).Debugf("Discarding redundant notice of resource allocation on network %s for task id %s", target, attacher.taskID)
        c.mu.Unlock()
        return nil
    }
    attacher.inProgress = true
    c.mu.Unlock()

    attacher.attachWaitCh <- config

    return nil
}

// WaitForDetachment waits for the container to stop or detach from
// the network.
func (c *Cluster) WaitForDetachment(ctx context.Context, networkName, networkID, taskID, containerID string) error {
    c.mu.RLock()
    attacher, ok := c.attachers[attacherKey(networkName, containerID)]
    if !ok {
        attacher, ok = c.attachers[attacherKey(networkID, containerID)]
    }
    state := c.currentNodeState()
    if state.swarmNode == nil || state.swarmNode.Agent() == nil {
        c.mu.RUnlock()
        return errors.New("invalid cluster node while waiting for detachment")
    }

    c.mu.RUnlock()
    agent := state.swarmNode.Agent()
    if ok && attacher != nil &&
        attacher.detachWaitCh != nil &&
        attacher.attachCompleteCh != nil {
        // Attachment may be in progress still so wait for
        // attachment to complete.
        select {
        case <-attacher.attachCompleteCh:
        case <-ctx.Done():
            return ctx.Err()
        }

        if attacher.taskID == taskID {
            select {
            case <-attacher.detachWaitCh:
            case <-ctx.Done():
                return ctx.Err()
            }
        }
    }

    return agent.ResourceAllocator().DetachNetwork(ctx, taskID)
}

// AttachNetwork generates an attachment request towards the manager.
func (c *Cluster) AttachNetwork(target string, containerID string, addresses []string) (*network.NetworkingConfig, error) {
    aKey := attacherKey(target, containerID)
    c.mu.Lock()
    state := c.currentNodeState()
    if state.swarmNode == nil || state.swarmNode.Agent() == nil {
        c.mu.Unlock()
        return nil, errors.New("invalid cluster node while attaching to network")
    }
    if attacher, ok := c.attachers[aKey]; ok {
        c.mu.Unlock()
        return attacher.config, nil
    }

    agent := state.swarmNode.Agent()
    attachWaitCh := make(chan *network.NetworkingConfig)
    detachWaitCh := make(chan struct{})
    attachCompleteCh := make(chan struct{})
    c.attachers[aKey] = &attacher{
        attachWaitCh:     attachWaitCh,
        attachCompleteCh: attachCompleteCh,
        detachWaitCh:     detachWaitCh,
    }
    c.mu.Unlock()

    ctx := context.TODO()
    ctx, cancel := context.WithTimeout(ctx, swarmRequestTimeout)
    defer cancel()

    taskID, err := agent.ResourceAllocator().AttachNetwork(ctx, containerID, target, addresses)
    if err != nil {
        c.mu.Lock()
        delete(c.attachers, aKey)
        c.mu.Unlock()
        return nil, fmt.Errorf("Could not attach to network %s: %v", target, err)
    }

    c.mu.Lock()
    c.attachers[aKey].taskID = taskID
    close(attachCompleteCh)
    c.mu.Unlock()

    log.G(ctx).Debugf("Successfully attached to network %s with task id %s", target, taskID)

    release := func() {
        ctx := context.WithoutCancel(ctx)
        ctx, cancel := context.WithTimeout(ctx, swarmRequestTimeout)
        defer cancel()
        if err := agent.ResourceAllocator().DetachNetwork(ctx, taskID); err != nil {
            log.G(ctx).Errorf("Failed remove network attachment %s to network %s on allocation failure: %v",
                taskID, target, err)
        }
    }

    var config *network.NetworkingConfig
    select {
    case config = <-attachWaitCh:
    case <-ctx.Done():
        release()
        return nil, fmt.Errorf("attaching to network failed, make sure your network options are correct and check manager logs: %v", ctx.Err())
    }

    c.mu.Lock()
    c.attachers[aKey].config = config
    c.mu.Unlock()

    log.G(ctx).Debugf("Successfully allocated resources on network %s for task id %s", target, taskID)

    return config, nil
}

// DetachNetwork unblocks the waiters waiting on WaitForDetachment so
// that a request to detach can be generated towards the manager.
func (c *Cluster) DetachNetwork(target string, containerID string) error {
    aKey := attacherKey(target, containerID)

    c.mu.Lock()
    attacher, ok := c.attachers[aKey]
    delete(c.attachers, aKey)
    c.mu.Unlock()

    if !ok {
        return fmt.Errorf("could not find network attachment for container %s to network %s", containerID, target)
    }

    close(attacher.detachWaitCh)
    return nil
}

// CreateNetwork creates a new cluster managed network.
func (c *Cluster) CreateNetwork(s network.CreateRequest) (string, error) {
    if networkSettings.IsPredefined(s.Name) {
        err := notAllowedError(fmt.Sprintf("%s is a pre-defined network and cannot be created", s.Name))
        return "", errors.WithStack(err)
    }

    var resp *swarmapi.CreateNetworkResponse
    if err := c.lockedManagerAction(func(ctx context.Context, state nodeState) error {
        networkSpec := convert.BasicNetworkCreateToGRPC(s)
        r, err := state.controlClient.CreateNetwork(ctx, &swarmapi.CreateNetworkRequest{Spec: &networkSpec})
        if err != nil {
            return err
        }
        resp = r
        return nil
    }); err != nil {
        return "", err
    }

    return resp.Network.ID, nil
}

// RemoveNetwork removes a cluster network.
func (c *Cluster) RemoveNetwork(input string) error {
    return c.lockedManagerAction(func(ctx context.Context, state nodeState) error {
        nw, err := getNetwork(ctx, state.controlClient, input)
        if err != nil {
            return err
        }

        _, err = state.controlClient.RemoveNetwork(ctx, &swarmapi.RemoveNetworkRequest{NetworkID: nw.ID})
        return err
    })
}

func (c *Cluster) populateNetworkID(ctx context.Context, client swarmapi.ControlClient, s *types.ServiceSpec) error {
    // Always prefer NetworkAttachmentConfigs from TaskTemplate
    // but fallback to service spec for backward compatibility
    networks := s.TaskTemplate.Networks
    if len(networks) == 0 {
        networks = s.Networks //nolint:staticcheck // ignore SA1019: field is deprecated.
    }
    for i, nw := range networks {
        apiNetwork, err := getNetwork(ctx, client, nw.Target)
        if err != nil {
            ln, _ := c.config.Backend.FindNetwork(nw.Target)
            if ln != nil && networkSettings.IsPredefined(ln.Name()) {
                // Need to retrieve the corresponding predefined swarm network
                // and use its id for the request.
                apiNetwork, err = getNetwork(ctx, client, ln.Name())
                if err != nil {
                    return errors.Wrap(errdefs.NotFound(err), "could not find the corresponding predefined swarm network")
                }
                goto setid
            }
            if ln != nil && !ln.Dynamic() {
                errMsg := fmt.Sprintf("The network %s cannot be used with services. Only networks scoped to the swarm can be used, such as those created with the overlay driver.", ln.Name())
                return errors.WithStack(notAllowedError(errMsg))
            }
            return err
        }
    setid:
        networks[i].Target = apiNetwork.ID
    }
    return nil
}