Excel services in SharePoint allows use simply, Share and manage the excel workbooks at enterprise level. In excel service we have three sub components for interaction in excel services. Excel calculation service, excel web access, Excel web service, User defined functions, ECMA Script, and REST service as shown in the image below. Excel web access, web services, Calculation service, User defined functions, ECMA script are divided into two groups as Web Front end (front-end server) and application server (back-end application server)
Excel Web Services, REST API, ECMA Script can be divided in to components of front-end server and User Defined Functions and Excel Calculation services are divided in to components of Application Server.
Excel web access renders the workbooks on a webpage and allows users to interact with the workbooks and explore them. Web Access is the excel service component that visible to the user without installing anything in the client machine.
Excel web services is the component that provides programmatic access to the web service. We can develop the applications to calculate, set and get the values form excel workbooks by using the excel web services.
Excel calculation services helps to load the workbooks, calculate, to call custom user defined functions and refreshes the external data. It will maintain the sessions in the interactions with workbook. Excel services also maintain the caching for opened excel workbooks, calculation states and data query results for improved performance.
User defined functions allows us to call the custom managed code functions and deployed to SharePoint server.
REST API enables to access workbook elements using URL. The URL contains a path for entry point to an aspx page. Excel services REST API enables the developers to explore the content workbook.
We can publish the excel workbooks through excel service in SharePoint. We can manage and secure the published work books according to the enterprise needs. Excel services was introduced in SharePoint 2007 and available in SharePoint 2013 enterprise version. The primary usage of the excel services is business intelligence. Excel workbooks can be connected in to external web sources and workbooks can be published in SharePoint doc library. As mentioned earlier, Excel services will helps to render the excel work book in the browser.
Create Excel Service application
To create the excel service application; “Excel Calculation Service” must be started in the server. To start the excel calculation service, click on “Manage Services on server” link in Application Management.
Select the server where we want to start the service above the services list and in the services list, start the excel calculation service.
Navigate to “Application Manage management” page and Click on “Manage Service Applications” link to create new Excel service application.
Click “New” button and select “Excel Services Application”
Enter the Name of the excel service application in create new excel service application page.
Select “Create new application pool” radio button and enter application pool name and specify the service account to run the application pool. Check “Add this service application's proxy to the farm's default proxy list. ” Check box to add the service to the default proxy list.