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: channels_server.go
    path of file: ./repos/azure-sdk-for-go/sdk/resourcemanager/engagementfabric/armengagementfabric/fake
    
    the code of the file until where you have to start completion: //go:build go1.18
// +build go1.18

// Copyright (c) Microsoft Corporation. All rights reserved.
// Licensed under the MIT License. See License.txt in the project root for license information.
// Code generated by Microsoft (R) AutoRest Code Generator. DO NOT EDIT.
// Changes may cause incorrect behavior and will be lost if the code is
    
func (c *ChannelsServerTransport) Do(req *http.Request) (*http.Response, error) {
	rawMethod := req.Context().Value(runtime.CtxAPINameKey{})
	method, ok := rawMethod.(string)
	if !ok {
		return nil, nonRetriableError{errors.New("unable to dispatch request, missing value for CtxAPINameKey")}
	}

	var resp *http.Response
	var err error

	switch method {
	case "ChannelsClient.CreateOrUpdate":
		resp, err = c.dispatchCreateOrUpdate(req)
	case "ChannelsClient.Delete":
		resp, err = c.dispatchDelete(req)
	case "ChannelsClient.Get":
		resp, err = c.dispatchGet(req)
	case "ChannelsClient.NewListByAccountPager":
		resp, err = c.dispatchNewListByAccountPager(req)
	default:
		err = fmt.Errorf("unhandled API %s", method)
	}

	if err != nil {
		return nil, err
	}

	return resp, nil
}