A Close Look Inside the SharePoint Engine

Randy Williams, MVP MOSS

Synergy Corporate Technologies

rwilliams@synergyonline.com

Session Overview

• SharePoint as a Product and Technology• Provisioning Engine

● IIS● SQL Server● Application / Site Pages (12 Hive)

• Execution Engine● ASP.NET

• Virtualization and Redirection

SharePoint Product Stack

Windows Server

IIS

.NET Framework

WSS

ADSQL

Server

MOSS

SharePoint Layers

.NET 2.0 Framework

.NET 3.0 Framework

WSS & MOSS UI

Windows APIOS

.NET

SharePointTechnologies(API)

Web Services

SharePointProducts

SharePoint Object Models

Layers in Action

Object Model

UI

Windows API

Web Services

.NET Framework

WordBrowserClient

Server

External Systems

Role of IIS

• Requests are directed to IIS Web Site● Defined by IP address, port & host header

• Virtual Directories• Application Pools

● Defines worker processes (w3wp.exe) ● Isolation vs efficiency● Process identity

• Coordinates authentication● Active Directory (Kerberos/NTLM/Basic)● LDAP / FBA

ASP.NET

• Part of .NET Framework 2.0• Integrates with IIS via ISAPI extension

● aspnet_isapi.dll• Provides processing engine for pages

● .aspx, .ascx, .master, etc.• Configured using web.config

web.config

• XML file for SharePoint configuration• One per web application• Controls provisioning engine• Controls authentication• Defines security

Provisioning Web Applications

• SharePoint creates/extends IIS Web Site● Creates files inside inetpub\wwwroot● Customizes web.config● Creates four virtual directories● Replicates this on multiple WFEs

• Done using Central Admin or stsadm• Requires farm-level admin• All site collections and webs are virtual

Role of SQL Server

• Repository for config, search, and content databases

• Config database● Farm-wide configuration settings

• Accessing tables directly is strongly discouraged and unsupported

SQL Content Database

• Container for site collections● Holds all SharePoint content

• Basic rules● Web application can have more than one● One database cannot span Web applications● One site collection cannot span db’s

• With Windows authentication, login to SQL is with app pool identity

SQL Content Database

• When creating a site collection● SharePoint selects “most available” db

• Based on site warning and max number levels

● STSADM –o createsiteinnewdb to specify● STSADM –o mergecontentdbs to move

• Best practices● Keep db’s small (< 100-200 GB)● Spread site collections among multiple db’s

Demo - Provisioning Web Application

12 Hive

• SharePoint’s file system components● C:\Program Files\Common Files\Microsoft Shared\

web server extensions\12\

• Contains:● Application pages● User controls● Web services● Assemblies and executables● Site definitions● Features

12 Hive

• Web Service files

• Admin Pages

• User Controls

• Features

• Images

• Application Pages

• Site Definitions

• Custom Field Types

SharePoint as a Provisioning Engine

• Primary design goals● Scalable● Flexible (Customizable)

• Challenges in achieving both• The solution is to support different types of

pages● Application pages● Site pages

Application Pages

• Farm wide - stored in 12 Hive● Referenced in _layouts virtual directory

• Shared by all webs, site collections and web applications

• Example● http://contoso/_layouts/settings.aspx● http://contoso/web/_layouts/settings.aspx● http://www.contoso.com/_layouts/settings.aspx

Site Pages

• Consist of list pages, home pages, master pages, new pages created, and others● NewForm.aspx, default.aspx, mypage.aspx

• Can be stored in 12 Hive or content database

• Can be customized using SPD● Customized vs uncustomized

Uncustomized Pages

• Similar to application pages• Stored in 12 Hive

● SiteTemplates & Features folders• Page is virtualized across multiple

SharePoint webs• Pages are compiled and code is cached• Very scalable• AKA ghosted pages

Customized Pages

• Site page that has been modified using SPD

• Now stored in content db• Page is not compiled

● Security risks• Page is not cached• Much slower due to overhead• Very flexible

Virtualization and Redirection

• Q: How does SharePoint support both customized & uncustomized pages?

• A: By a virtual path provider called SPVirtualPathProvider

• Part of SPRequest HTTP module● Referenced in web.config

• Based on ASP.NET 2.0 technology

SharePoint’s HTTP Request Pipeline

Browser W3wp.exe

ASP.NET ISAPI

SPVirtualPathProvider

Content db

File System

Customized

Uncustomized

HTTP.SYS

Site Page Rendering

Master Page

NavCSS JS

Images

WebPartManager

Site Page

Master PageWeb

Parts

WebPartZoneWebPartZones

DelegateControls

ContentPlace

Holders

Questions?

• My blog● http://sharepointhawaii.com/randywilliams