You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: service_update.go
    path of file: ./repos/podman/vendor/github.com/docker/docker/client
    
    the code of the file until where you have to start completion: package client // import "github.com/docker/docker/client"

import (
	"context"
	"encoding/json"
	"net/http"
	"net/url"

	"github.com/docker/docker/api/types"
	"github.com/docker/docker/api/types/registry"
	"github.com/docker/docker/api/types/swarm"
	"github.com/docker/docker/api/types/versions"
)

// ServiceUpdate updates a Service. The version number is required to avoid conflicting writes.
// It should be the value as set *before* the update. You can find this value in the Meta field
// of swarm.Service, which can be found using ServiceInspectWithRaw.
func (cli *Client) ServiceUpdate(ctx context.Context, serviceID string, version swarm.Version, service swarm.ServiceSpec, options types.ServiceUpdateOptions) (swarm.ServiceUpdateResponse, error) {
	// Make sure we negotiated (if the client is configured to do so),
	// as code below contains API-version specific handling of options.
	//
	// Normally, version-negotiation (if enabled) would not happen until
	// the API request is made.
	cli.checkVersion(ctx)

	var (
		query    = url.Values{}
		response = swarm.ServiceUpdateResponse{}
	)

	if options.RegistryAuthFrom != "" {
		query.Set("registryAuthFrom", options.RegistryAuthFrom)
	}

	if options.Rollback != "" {
		query.Set("rollback", options.Rollback)
	}

	query.Set("version", version.String())

	if err := validateServiceSpec(service); err != nil {
		return response, err
	}

	/
    
func (cli *Client) ServiceUpdate(ctx context.Context, serviceID string, version swarm.Version, service swarm.ServiceSpec, options types.ServiceUpdateOptions) (swarm.ServiceUpdateResponse, error) {
	// Make sure we negotiated (if the client is configured to do so),
	// as code below contains API-version specific handling of options.
	//
	// Normally, version-negotiation (if enabled) would not happen until
	// the API request is made.
	cli.checkVersion(ctx)

	var (
		query    = url.Values{}
		response = swarm.ServiceUpdateResponse{}
	)

	if options.RegistryAuthFrom != "" {
		query.Set("registryAuthFrom", options.RegistryAuthFrom)
	}

	if options.Rollback != "" {
		query.Set("rollback", options.Rollback)
	}

	query.Set("version", version.String())

	if err := validateServiceSpec(service); err != nil {
		return response, err
	}

	// ensure that the image is tagged
	var resolveWarning string
	switch {
	case service.TaskTemplate.ContainerSpec != nil:
		if taggedImg := imageWithTagString(service.TaskTemplate.ContainerSpec.Image); taggedImg != "" {
			service.TaskTemplate.ContainerSpec.Image = taggedImg
		}
		if options.QueryRegistry {
			resolveWarning = resolveContainerSpecImage(ctx, cli, &service.TaskTemplate, options.EncodedRegistryAuth)
		}
	case service.TaskTemplate.PluginSpec != nil:
		if taggedImg := imageWithTagString(service.TaskTemplate.PluginSpec.Remote); taggedImg != "" {
			service.TaskTemplate.PluginSpec.Remote = taggedImg
		}
		if options.QueryRegistry {
			resolveWarning = resolvePluginSpecRemote(ctx, cli, &service.TaskTemplate, options.EncodedRegistryAuth)
		}
	}

	headers := http.Header{}
	if versions.LessThan(cli.version, "1.30") {
		// the custom "version" header was used by engine API before 20.10
		// (API 1.30) to switch between client- and server-side lookup of
		// image digests.
		headers["version"] = []string{cli.version}
	}
	if options.EncodedRegistryAuth != "" {
		headers[registry.AuthHeader] = []string{options.EncodedRegistryAuth}
	}
	resp, err := cli.post(ctx, "/services/"+serviceID+"/update", query, service, headers)
	defer ensureReaderClosed(resp)
	if err != nil {
		return response, err
	}

	err = json.NewDecoder(resp.body).Decode(&response)
	if resolveWarning != "" {
		response.Warnings = append(response.Warnings, resolveWarning)
	}

	return response, err
}