Component SQL Server in Visual Basic .NET

Create Data Matrix in Visual Basic .NET Component SQL Server

AWReporterWeb Anonymous access (Campaigner Web service) (rights to write to AWCSpecialDeals.xml) Report Server Windows Integrated

In this test environment, the SQL Server runs under the context of the Local System account. Because this is a local account, its identity cannot cross the machine boundary when the web method invocation occurs. For this reason, you have at least two choices for authenticating the SQL Server call to the Campaigner Web service:

Change the SQL Server process identity to a domain account or a local account that is duplicated on the machine where the Campaigner Web service is installed (this has the same name and password). Set up the AWReporterWeb vroot to allow anonymous access. For testing purposes, we ll adopt the latter approach, but in real life you should carefully consider the ramifications of using Anonymous access. When Anonymous access is enabled, IIS authenticates all users using a low-privileged Windows account (IUSR_computername by default), which is a member of the Guest Windows group. All requests to access local resources go under the identity of this account. In this case, the StartCampaign method needs to write to the blog file. For this reason, you need to grant the Anonymous account write permissions to this file. Alternatively, you can change the Anonymous identity to an account that has an elevated set of permissions. Finally, you need to take care of setting the identity of the cross-machine call from the Campaigner Web service to the Report Server. Here, again you have two options: Impersonating the user Assuming that Anonymous access is enabled, this means that we will pass the identity of the Anonymous account to the Report Server. Again, in order for the cross-machine call to succeed between the Campaigner machine and the Report Server machine, this account has to be a domain account or a duplicated local account, which exists on both machines. Using the trusted subsystem approach by passing the Campaigner Web service identity to the Report Server You can change the identity of the ASP.NET worker process on the machine where the Campaigner Web service is running to a domain account. In both cases, you have to set up a role-based security policy in the Report Server to grant the Campaigner account sufficient rights to view the Sales Promotion report and SalesPromotion.xsl file. Now that you have a good high-level overview of both access options available for requesting reports, let s wrap up our discussion by comparing these options.

Choosing the right integration scenario for report-enabling your applications can be challenging. You need to make a careful decision between the ease of use in the case of URL access and the flexibility offered by the RS Web service. Here are some of the questions that you need to ask yourself: Is this an intranet or Internet-oriented application While both access options can be used with intranet-oriented applications, unless you use a custom security extension, Internet reporting in most cases will require requesting reports by SOAP.

Can the Report Server be accessed directly by the client application If the answer is no (for security, or other reasons), then SOAP is the only choice. Does the report request need to be validated before it is handed out to the Report Server If business rules need to be validated before the report request is authorized, SOAP may be the better choice. How will the report parameters be handled If the HTML Viewer fits the bill, it would be naive not to take advantage of URL access. In general, we recommend that you evaluate URL access first and only if it doesn t meet your integration requirements should you settle on Web service access. As you ve seen in this chapter, there are good reasons to keep things simple, and simplicity is the biggest strength of URL access. Let s enumerate the pros and cons of each option in more detail to help you with the decision-making process. 10.6.1 Evaluating URL access In general, URL access is best suited for interactive, intranet-oriented applications where the report request can originate on the client side of the application. Pros of URL access The advantages of this approach are as follows: Simplicity Compared to requesting reports by SOAP, URL access is far easier. No postprocessing steps are required to render the report payload. The browser handles report sessions automatically. In case of HTML reports, you don t have to worry about downloading the image files. If you are using SOAP, taking care of the report images and charts could be a hassle, especially for Internet-based reports. Relatively easy to integrate with client applications Due to the venerable history of the HTTP protocol, most development tools and platforms can handle HTTP-GET requests and responses. No client footprint Usually, there will be nothing that you need to install to integrate a client application with RS by URL. It could be as easy as embedding the report s URL in a hyperlink. For example, you can have a SharePoint Web part that references a report by URL. Interactive features You can leverage URL access to provide a rich user experience by adding interactive features to your reports, such as drilldown, toggled visibility, document maps, navigational features, and the HTML Viewer. When a report with interactive features is requested in HTML, the Report Server embeds the request-specific details, such as the parameter values, in the report page. When the interactive feature is requested by the end user, for example to perform a drilldown, the report spawns an HTTP-GET request to the Report Server to refresh itself. 384