Chapter 3. Exploring the Internals of Remote Authoring
Understanding the basics of remote authoring
Working with Web Folders and Web clients
Understanding FrontPage Remote Procedure Call
Understanding Simple Object Access Protocol and Web Services basics
While the process of opening Web sites, live editing of Web pages, or publishing Web content in SharePoint Designer looks simple and straightforward on the surface, these procedures are quite complex, and a lot of client-server communication technologies are employed to accomplish even the most basic of operations. It's important as a Web site designer that you have some understanding of these underlying client-server communication protocols and technologies so that you can diagnose and troubleshoot problems associated with content authoring in SharePoint Designer. In this chapter, I introduce you to some of the key underlying communication protocols that SharePoint Designer uses for its site authoring and management operations. I also explain how some of the Windows (OS) components are used by SharePoint Designer to allow for its remote authoring and publishing features. Finally, I discuss some remote-authoring protocols and technologies that provide the foundation for SharePoint Designer capabilities of working with FPSE and SharePoint sites.
Throughout this chapter, you capture the client-server communication between SharePoint Designer and the Web server hosting the Web site content to develop understanding on the background processes and mechanisms used. Before I begin, I want to familiarize you with the Fiddler tool, which I use for capturing client-server communication.
Fiddler is a proxy-based HTTP debugging tool that allows you to capture HTTP (or HTTPS for HTTP over a secure socket) traffic originating from and finishing at a machine where Fiddler is installed and run. It provides an intuitive user interface that can be used to easily capture and understand HTTP-based communication.
The latest release of Fiddler at the time of this writing is Fiddler 2 and is available for download at www.fiddler2.com. The setup requirements, installation steps, and basic operations guide for Fiddler are also available at this Web site.
To better understand how to use Fiddler, the following steps help capture the client-server traffic that occurs when you open a WSS v3 team site in Internet Explorer. To reduce the captured traffic, ensure that all Web browsers and other Web-based applications installed on your computer are closed before you begin these steps. Also, ensure you have downloaded and installed Fiddler 2 before doing the following:
Choose Edit
Remove 
All Sessions to clear the Web Sessions pane.While keeping Fiddler running, open Internet Explorer (or any other Web browser, such as Firefox, Opera, etc.) and then browse to a WSS v3 Web site based on the Team Site template.
After the default page of the Web site displays in the browser, switch back to the Fiddler tool. The Web Sessions pane in Fiddler is now filled with rows of HTTP sessions.
Choose File
Capture Traffic (or press F12) to direct Fiddler to stop capturing HTTP traffic. A Web session in Fiddler is basically composed of two components: an HTTP request from the client machine for a resource (such as a Web page, style sheet, picture, JavaScript, etc.) and the HTTP response from the server machine for the request. As shown in Figure 3.1, the Result column in the Web Sessions pane shows the HTTP response code for the request, the Host column shows the Web site URL, and the URL column shows the relative URL of the resource being requested.In the list of captured Web sessions, find the one where the Result column shows 200 and the URL column shows /default.aspx. The result 200 here implies a successful Web server response. This Web session corresponds to the request for the default Web page of the WSS v3 site you opened in IE in the previous step and the response from the SharePoint Web server for it.
Double-click the Web session to activate the Session Inspector tab on the right pane of Fiddler. You use the Session Inspector tab to see the actual text of the HTTP request and the HTTP response associated with the Web session. The top window in the Session Inspector shows the HTTP request, and the bottom window shows the HTTP response.
On the menu inside the Session Inspector window, click the Raw button to view the raw HTTP request and the response associated with the Web session. The top window of the Session Inspector shows the request to GET (an HTTP verb) the default.aspx page by using the HTTP 1.1 Web protocol. The request also includes a number of HTTP headers (User-Agent, Authorization, Set-Cookie, etc.) that the Web server uses to identify the Web browser, retrieve the user credentials for authentication, and perform other operations.
Figure 3.1. A Fiddler capture while opening the default page of a SharePoint site
The bottom window shows the HTTP response from the Web server. In the previous exercise, the server responded with an HTTP 200 OK response (indicating that the request was properly authenticated and processed), some HTTP response headers, and the complete HTML code of the default.aspx Web page (obtained by the server-side processing of the ASP.NET code of the Web page) that's actually interpreted and displayed by a Web browser.
While the previous steps should help in understanding how to use the Fiddler tool to capture HTTP traffic, I use this tool later in this chapter to help you understand the internals of SharePoint authoring in SharePoint Designer.