We have seen what cloud computing is and how it is different than the normal software development. We have seen the different types of models, SaaS, PaaS, and IaaS used with cloud computing.
This chapter will introduce you to the Force.com platform. We will understand the life cycle of an application build using Force.com. We will define the multi-tenant architecture and understand how it will impact the data of the organization stored on the cloud. And finally, we will build our first application on Force.com.
The agenda for this chapter is as follows:
- The cloud computing model of Force.com
- Understand the PaaS model of Force.com
- Application development on Force.com
- Maintenance and releases
- Types of Force.com applications
- When to use point-and-click and when to use code
- Identity confirmation
- Developer resources
So let's get started and step into the cloud...
Force.com provides a 100 percent cloud computing model for enterprise application. The end-user does not have to worry about networks, hardware, software licenses, and so on. Everything is done on the cloud. The following features of Force.com make it a 100 percent cloud-based system:
- Multi-tenant architecture: The multi-tenant architecture is a way of serving multiple clients on the single software instance. Each client gets their own full version of the software configuration and data. They cannot utilize the other instance resources. The software is virtually partitioned into different instances. The basic structure of the multi-tenant architecture is as shown in the following image:
Just like tenants in a single building share the resources of electricity and water, the multi-tenant system shares common resources. Separate programs are written to ensure that a single instance does not monopolize the resources.
- Automatic upgrades:The newer version of the application is released automatically with all the users. Any developments or customizations made during the previous version are automatically updated to the latest version without any manual modification to the code.
- Subscription model: Force.com is distributed under the subscription model. The user can purchase a few licenses and build the system. After the system is up and successful, further user licenses can be purchased from Salesforce. This model ensures that there no large start-up fee and we pay as we go, which adds fixed, predictable costs in the future.
The subscription model can be visualized like the electricity distribution system. We pay for whatever electricity we use and not the complete generator and the infrastructure.
- Scalability: The multi-tenant kernel is already tested and running for many users simultaneously. If the organization is growing, there is always room for scaling the application with new users without worrying about the load balancing and data limitation. Force.com provides data storage per user, which means that the data storage increases with the number of users added to the organization.
- Upgrades and maintenance: Force.com releases three updated versions every year. The new releases consist of feature updates to Salesforce.com and the Force.com platform with selected top ideas from IdeaExchange. IdeaExchange is the community of Salesforce users where the users submit ideas and the community votes for them. The most popular ideas are considered by Salesforce in their next release.
All the instances hosted on the servers are upgraded with no additional cost. The sandboxes are upgraded early so there can be testing for compatibility to the new release. The new releases are backward compatible with previous releases, thus the old code will work with new versions. The upgrades are taken care of by Force.com and the end-user gets the latest version running application.