docker/swarmkit

package agent

import (
    "context"

    "github.com/moby/swarmkit/v2/api"
)

type resourceAllocator struct {
    agent *Agent
}

// ResourceAllocator is an interface to allocate resource such as
// network attachments from a worker node.
type ResourceAllocator interface {
    // AttachNetwork creates a network attachment in the manager
    // given a target network and a unique ID representing the
    // connecting entity and optionally a list of ipv4/ipv6
    // addresses to be assigned to the attachment. AttachNetwork
    // returns a unique ID for the attachment if successful or an
    // error in case of failure.
    AttachNetwork(ctx context.Context, id, target string, addresses []string) (string, error)

    // DetachNetworks deletes a network attachment for the passed
    // attachment ID. The attachment ID is obtained from a
    // previous AttachNetwork call.
    DetachNetwork(ctx context.Context, aID string) error
}

// AttachNetwork creates a network attachment.
func (r *resourceAllocator) AttachNetwork(ctx context.Context, id, target string, addresses []string) (string, error) {
    var taskID string
    if err := r.agent.withSession(ctx, func(session *session) error {
        client := api.NewResourceAllocatorClient(session.conn.ClientConn)
        r, err := client.AttachNetwork(ctx, &api.AttachNetworkRequest{
            Config: &api.NetworkAttachmentConfig{
                Target:    target,
                Addresses: addresses,
            },
            ContainerID: id,
        })
        if err != nil {
            return err
        }
        taskID = r.AttachmentID
        return nil
    }); err != nil {
        return "", err
    }

    return taskID, nil
}

// DetachNetwork deletes a network attachment.
func (r *resourceAllocator) DetachNetwork(ctx context.Context, aID string) error {
    return r.agent.withSession(ctx, func(session *session) error {
        client := api.NewResourceAllocatorClient(session.conn.ClientConn)
        _, err := client.DetachNetwork(ctx, &api.DetachNetworkRequest{
            AttachmentID: aID,
        })

        return err
    })
}

// ResourceAllocator provides an interface to access resource
// allocation methods such as AttachNetwork and DetachNetwork.
func (a *Agent) ResourceAllocator() ResourceAllocator {
    return &resourceAllocator{agent: a}
}