예제 #1
0
파일: runtime.go 프로젝트: Nerdness/docker
// Create creates a new container from the given configuration with a given name.
func (runtime *Runtime) Create(config *Config, name string) (*Container, []string, error) {
	// Lookup image
	img, err := runtime.repositories.LookupImage(config.Image)
	if err != nil {
		return nil, nil, err
	}

	// We add 2 layers to the depth because the container's rw and
	// init layer add to the restriction
	depth, err := img.Depth()
	if err != nil {
		return nil, nil, err
	}

	if depth+2 >= MaxImageDepth {
		return nil, nil, fmt.Errorf("Cannot create container with more than %d parents", MaxImageDepth)
	}

	checkDeprecatedExpose := func(config *Config) bool {
		if config != nil {
			if config.PortSpecs != nil {
				for _, p := range config.PortSpecs {
					if strings.Contains(p, ":") {
						return true
					}
				}
			}
		}
		return false
	}

	warnings := []string{}
	if checkDeprecatedExpose(img.Config) || checkDeprecatedExpose(config) {
		warnings = append(warnings, "The mapping to public ports on your host has been deprecated. Use -p to publish the ports.")
	}

	if img.Config != nil {
		if err := MergeConfig(config, img.Config); err != nil {
			return nil, nil, err
		}
	}

	if len(config.Entrypoint) != 0 && config.Cmd == nil {
		config.Cmd = []string{}
	} else if config.Cmd == nil || len(config.Cmd) == 0 {
		return nil, nil, fmt.Errorf("No command specified")
	}

	// Generate id
	id := GenerateID()

	if name == "" {
		name, err = generateRandomName(runtime)
		if err != nil {
			name = utils.TruncateID(id)
		}
	} else {
		if !validContainerNamePattern.MatchString(name) {
			return nil, nil, fmt.Errorf("Invalid container name (%s), only %s are allowed", name, validContainerNameChars)
		}
	}

	if name[0] != '/' {
		name = "/" + name
	}

	// Set the enitity in the graph using the default name specified
	if _, err := runtime.containerGraph.Set(name, id); err != nil {
		if !strings.HasSuffix(err.Error(), "name are not unique") {
			return nil, nil, err
		}

		conflictingContainer, err := runtime.GetByName(name)
		if err != nil {
			if strings.Contains(err.Error(), "Could not find entity") {
				return nil, nil, err
			}

			// Remove name and continue starting the container
			if err := runtime.containerGraph.Delete(name); err != nil {
				return nil, nil, err
			}
		} else {
			nameAsKnownByUser := strings.TrimPrefix(name, "/")
			return nil, nil, fmt.Errorf(
				"Conflict, The name %s is already assigned to %s. You have to delete (or rename) that container to be able to assign %s to a container again.", nameAsKnownByUser,
				utils.TruncateID(conflictingContainer.ID), nameAsKnownByUser)
		}
	}

	// Generate default hostname
	// FIXME: the lxc template no longer needs to set a default hostname
	if config.Hostname == "" {
		config.Hostname = id[:12]
	}

	var args []string
	var entrypoint string

	if len(config.Entrypoint) != 0 {
		entrypoint = config.Entrypoint[0]
		args = append(config.Entrypoint[1:], config.Cmd...)
	} else {
		entrypoint = config.Cmd[0]
		args = config.Cmd[1:]
	}

	container := &Container{
		// FIXME: we should generate the ID here instead of receiving it as an argument
		ID:              id,
		Created:         time.Now().UTC(),
		Path:            entrypoint,
		Args:            args, //FIXME: de-duplicate from config
		Config:          config,
		hostConfig:      &HostConfig{},
		Image:           img.ID, // Always use the resolved image id
		NetworkSettings: &NetworkSettings{},
		Name:            name,
		Driver:          runtime.driver.String(),
	}
	container.root = runtime.containerRoot(container.ID)
	// Step 1: create the container directory.
	// This doubles as a barrier to avoid race conditions.
	if err := os.Mkdir(container.root, 0700); err != nil {
		return nil, nil, err
	}

	initID := fmt.Sprintf("%s-init", container.ID)
	if err := runtime.driver.Create(initID, img.ID); err != nil {
		return nil, nil, err
	}
	initPath, err := runtime.driver.Get(initID)
	if err != nil {
		return nil, nil, err
	}
	defer runtime.driver.Put(initID)

	if err := setupInitLayer(initPath); err != nil {
		return nil, nil, err
	}

	if err := runtime.driver.Create(container.ID, initID); err != nil {
		return nil, nil, err
	}
	resolvConf, err := utils.GetResolvConf()
	if err != nil {
		return nil, nil, err
	}

	if len(config.Dns) == 0 && len(runtime.config.Dns) == 0 && utils.CheckLocalDns(resolvConf) {
		//"WARNING: Docker detected local DNS server on resolv.conf. Using default external servers: %v", defaultDns
		runtime.config.Dns = defaultDns
	}

	// If custom dns exists, then create a resolv.conf for the container
	if len(config.Dns) > 0 || len(runtime.config.Dns) > 0 {
		var dns []string
		if len(config.Dns) > 0 {
			dns = config.Dns
		} else {
			dns = runtime.config.Dns
		}
		container.ResolvConfPath = path.Join(container.root, "resolv.conf")
		f, err := os.Create(container.ResolvConfPath)
		if err != nil {
			return nil, nil, err
		}
		defer f.Close()
		for _, dns := range dns {
			if _, err := f.Write([]byte("nameserver " + dns + "\n")); err != nil {
				return nil, nil, err
			}
		}
	} else {
		container.ResolvConfPath = "/etc/resolv.conf"
	}

	// Step 2: save the container json
	if err := container.ToDisk(); err != nil {
		return nil, nil, err
	}

	// Step 3: register the container
	if err := runtime.Register(container); err != nil {
		return nil, nil, err
	}
	return container, warnings, nil
}
예제 #2
0
파일: driver.go 프로젝트: Nerdness/docker
// CreateBridgeIface creates a network bridge interface on the host system with the name `ifaceName`,
// and attempts to configure it with an address which doesn't conflict with any other interface on the host.
// If it can't find an address which doesn't conflict, it will return an error.
func createBridge(bridgeIP string) error {
	nameservers := []string{}
	resolvConf, _ := utils.GetResolvConf()
	// we don't check for an error here, because we don't really care
	// if we can't read /etc/resolv.conf. So instead we skip the append
	// if resolvConf is nil. It either doesn't exist, or we can't read it
	// for some reason.
	if resolvConf != nil {
		nameservers = append(nameservers, utils.GetNameserversAsCIDR(resolvConf)...)
	}

	var ifaceAddr string
	if len(bridgeIP) != 0 {
		_, _, err := net.ParseCIDR(bridgeIP)
		if err != nil {
			return err
		}
		ifaceAddr = bridgeIP
	} else {
		for _, addr := range addrs {
			_, dockerNetwork, err := net.ParseCIDR(addr)
			if err != nil {
				return err
			}
			if err := networkdriver.CheckNameserverOverlaps(nameservers, dockerNetwork); err == nil {
				if err := networkdriver.CheckRouteOverlaps(dockerNetwork); err == nil {
					ifaceAddr = addr
					break
				} else {
					utils.Debugf("%s %s", addr, err)
				}
			}
		}
	}

	if ifaceAddr == "" {
		return fmt.Errorf("Could not find a free IP address range for interface '%s'. Please configure its address manually and run 'docker -b %s'", bridgeIface, bridgeIface)
	}
	utils.Debugf("Creating bridge %s with network %s", bridgeIface, ifaceAddr)

	if err := createBridgeIface(bridgeIface); err != nil {
		return err
	}

	iface, err := net.InterfaceByName(bridgeIface)
	if err != nil {
		return err
	}

	ipAddr, ipNet, err := net.ParseCIDR(ifaceAddr)
	if err != nil {
		return err
	}

	if netlink.NetworkLinkAddIp(iface, ipAddr, ipNet); err != nil {
		return fmt.Errorf("Unable to add private network: %s", err)
	}
	if err := netlink.NetworkLinkUp(iface); err != nil {
		return fmt.Errorf("Unable to start network bridge: %s", err)
	}
	return nil
}