- Force.com in the Cloud Computing Landscape
- Inside a Force.com Project
- Sample Application: Services Manager
- Summary
This chapter is from the book
This chapter is from the book
This chapter is from the book
Inside a Force.com Project
This section discusses what makes a Force.com project different from a typical corporate in-house software development effort, starting with project selection. Learn some tips for selecting a project in Force.com's sweet spot. Then examine how traditional technical roles translate to development activities in a Force.com project and how technologies within Force.com impact your product development lifecycle. Lastly, get acquainted with the tools and resources available to make your project a success.
Project Selection
Some projects are better suited to implementation on Force.com than others. It is possible to run into natural limits of the PaaS approach or battle against the abstraction provided by the platform. Always strive to pursue projects that play into Force.com strengths. There are no absolute rules for determining this, but projects with the following characteristics tend to work well with Force.com:
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The project is data-centered, requiring the storage and retrieval of structured data.
Structured data is the most important point. Implementing a YouTube-like application on Force.com is not the best idea, since it primarily works with unstructured data in the form of video streams. Force.com supports binary data, so a video-sharing Web site is certainly possible to build. But handling large amounts of binary data is not a focus or core competency of Force.com. A hotel reservation system is an example of a more natural fit.
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The user interface is composed primarily of wizards, grids, forms, reports.
Force.com does not restrict you to these user interface patterns. You can implement any type of user interface, including "rich" clients that run using Flash in the browser, and even full desktop applications that integrate with Force.com via its Apex Web Services API. But to capture the most benefit from the platform, stick with structured, data-driven user interfaces that use standard Web technologies such as HTML, CSS, and JavaScript.
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The underlying business processes involve email, spreadsheets, and hierarchies of people who participate in a distributed, asynchronous workflow.
Standard Force.com features such as workflow, approvals, and email services add a lot of value to these applications. They can be configured by business analysts or controlled in-depth by developers in Apex code.
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The rules around data sharing and security are fine-grained and based on organizational roles and user identity.
User identity management and security are deep subjects and typically require high effort to implement in a custom system. With Force.com they are standard, highly configurable components that you can leverage without coding. You can then spend more time thinking though the "who can see what" scenarios rather than coding the infrastructure to make them possible.
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The project requires integration with other systems.
Force.com is built from the ground up to interoperate with other systems at all its layers: data, business logic, and user interface. The infrastructure is taken care of, so you can focus on the integration design. Exchange a million rows of data between your SQL Server database and Force.com. Call your Apex services from a legacy J2EE application or vice versa. Add an event to a Google calendar from within your Visualforce user interface. These scenarios and more are fully supported by the platform.
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The project manipulates data incrementally, driven by user actions rather than a calendar.
Force.com is a shared resource. Simultaneously there are other customers of varying sizes using the same infrastructure. This requires Force.com to carefully monitor and fairly distribute the computing resources so that all customers can accomplish their goals with a high quality of service. If one customer's application on Force.com was allowed to consume a disproportionate share of resources, other customers' applications would suffer resource starvation. The limitations in place, called governors, prevent too much memory, CPU, disk, or network bandwidth from being concentrated in the hands of any one customer. The platform strongly enforces these governor limits, so the best Force.com applications involve computing tasks that can be split into small units of work.
- The data volume is limited, below a few million records per table.
Data volume is important to think about with any system: How large is my data going to grow and at what rate? Force.com consists of a logical single transactional database. There is no analytical data store. Applications that require access to large volumes of data, such as data warehousing and analytics, cannot be built on Force.com. Other software vendors provide solutions to this area, but all involve copying data from Force.com to their own products.
Force.com is not an all-or-nothing proposition. If your project does not fit within these guidelines, you might still want to explore Force.com but in conjunction with other PaaS solutions such as Amazon EC2. Thanks to Force.com's integration capabilities, EC2 and Force.com can be used together as a composite solution, EC2 augmenting Force.com where general-purpose computing is needed.
Team Selection
The best people to staff on Force.com projects might already work at your company. Projects do not require brand-new teams staffed with Force.com experts. With the majority of the platform based in mature technology such as relational databases and Web development, adapting existing teams can be a straightforward task.
Here are some examples of traditional software development roles and how they can contribute to a Force.com project:
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Business Analyst
Substantial Force.com applications can be built entirely by configuration, no computer science background or coding skills required. Salesforce refers to this as "clicks, not code." Business analysts who are proficient with Microsoft Excel and its macro language, or small-scale databases like Microsoft Access and FileMaker Pro, can get hands-on with the Force.com data model, validation rules, workflows, approval rules, and page layouts.
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Data Modeler
A data model forms the core of a Force.com application. Data modelers can use their existing Entity-Relationship tools and techniques to design the data layer, with some deltas to account for Force.com behavior. Rather than scripts of DDL statements, their work output is Force.com's metadata XML or manual configuration of the data objects. Data modelers can also design reports and report types, which define data domains available to business users to build their own reports.
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Database Administrator
Many traditional DBA tasks are obsolete in Force.com because there is no physical database to build, monitor, and tune. But a DBA still has plenty of work to do in planning and implementing the Force.com object model. There are objects to define or permissions to configure, and the challenges of data migration are still as relevant in Force.com as in any database-backed system.
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Database Developer
The design of Force.com's programming language, Apex, has clearly been inspired by stored procedure languages like T-SQL and PL/SQL. Existing database developers can adapt their skills to writing Apex code, particularly when it requires detailed work on the data like triggers.
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Object-Oriented Analysis and Design Specialist
Force.com includes an object-oriented language, and persistent data is represented as objects. With all of these objects floating around, people with skills in traditional techniques like Unified Modeling Language (UML) are valuable to have on your project team. Larger applications benefit from a well-designed object model, and as in any language, designing before writing Apex code can be a real timesaver.
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User Interface Designer
Force.com supports modern Web standards for creating usable, flexible, and maintainable UIs. UI designers can help by building screen mock-ups, page layouts, and the static portions of Visualforce pages to serve as templates.
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Web Developer
Developers who have built Web applications can quickly learn enough Apex and Visualforce and build similar applications on Force.com, typically with much less effort. Skills in HTML, CSS, JavaScript, or Adobe Flex are needed to build custom Force.com user interfaces.
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4GL Developer
Developers proficient in fourth-generation languages such as Java, C#.NET, and PHP have no problem picking up Apex code. It has the same core syntax as Java, minus the Java-specific libraries.
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Integration Specialist
Force.com is a producer and consumer of Web services and supports REST as well as any integration strategy based on HTTP. An integration expert can design the interaction between systems, define the remote operations, and implement them using Force.com or a dedicated integration product.
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Quality Assurance Engineer
Testing is a critical part of any software project, and on Force.com testing is mandatory before code is deployed to production. A QA engineer can write unit tests in Apex and test plans for security and integration testing. Standard tools like Selenium can be used to automate UI testing.
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Operations Specialist
Although there are no servers or operating systems to manage, larger deployments of Force.com can involve integration with on-premise systems. Single Sign On (SSO) integration and data migration are two common examples. Operations experts can help in this area, as well as with application deployment and Force.com administration tasks such as user maintenance.
Lifecycle
The software development lifecycle of a Force.com project is much like an on-premise Web application development project, but with less toil. There are many moving parts in J2EE, .NET, or LAMP projects. Most require a jumble of frameworks to be integrated and configured properly before one line of code relevant to your project is written. In fairly integrated environments like .NET on the Microsoft platform, there are fewer frameworks to be integrated but still plenty of infrastructure code to be written.
This section describes areas of Force.com functionality designed to streamline the development lifecycle and focus your time on the value-added activities related to your application. There are implicit costs and benefits in each of these areas. On the cost side, there is usually a loss of control and flexibility versus technologies with less abstraction. It is up to you to evaluate these features and judge whether they constitute costs or benefits for your project.
Integrated Logical Database
Relational databases are still the default choice for business applications, despite the availability of alternatives like XML and object-oriented databases. The relational model maps well onto business entities, data integrity is easily enforceable, and implementations scale to hold massive amounts of data while providing efficient recall, composition, and modification.
For business applications coded in an object-oriented language, accessing relational databases introduces an impedance mismatch. Databases organize data in terms of schemas, tables, and columns. Programs organize data and logic into objects, methods, and fields. There are many ways to juggle data between the two, none of them ideal. To make matters more complicated, there are many layers of protocol and message needed to transport queries, resultsets, and transactions between the program and the database.
In Force.com, the database tables are called objects. They are somewhat confusingly named because they do not exhibit entirely object-oriented behavior. The name comes from the fact that they are logical entities that act as tables when being defined, loaded with data, queried, updated, and reported on, but are surfaced to programs as first-class objects. There is no mismatch between the way data is represented in code and the way it's represented in the database. Your code remains consistent and concise whether you are working with in-memory instances of your custom-defined Apex classes or objects from the database. This also enables compile-time validation of programs, including queries and data manipulation statements, to ensure that they adhere to the database schema. This one seemingly simple feature eliminates a whole class of defects that were previously discovered only through unit tests or in production by unfortunate users.
The logical aspect of the database is also significant. Developers have no direct access to the physical databases running in Salesforce's data centers. The physical data model is a proprietary meta-model optimized for multitenant applications, with layers of caches and fault tolerance, spanning thousands of servers in multiple data centers. When you create an object in Force.com, no corresponding Oracle database table is created. The metadata describing your new table is stored and indexed by a series of physical tables, becoming a unified, tenant-specific vocabulary baked into the platform's higher-level features. The synergy of integrated, metadata-aware functionality makes Force.com much more than the sum of its features.
Metadata-Derived User Interface
As described previously, the definition of your objects becomes the vocabulary for other features. Nowhere is this more evident than in the standard Force.com user interface, commonly referred to as the "native" UI. This is the style pioneered by the Salesforce CRM: lots of tables, topped with fat bars of color with icons of dollar signs and telescopes, and a row of tabs for navigation. Lots of page refreshes too.
It is worth getting to know the capabilities of native UI even if you have reservations about its appearance or usability. To some it is an artifact of the Precambrian era of Web applications. To others it is a clean-cut business application, consistent and safe. Either way, as a developer you cannot afford to ignore it. The native UI is where many configuration tasks are performed, for features not yet visible to Eclipse and other tools.
If your project's user interface design is amenable to the native UI, you can build screens almost as fast as users can describe their requirements. Rapid application prototyping is an excellent addition or alternative to static screen mock-ups. Page layouts are descriptions of which fields appear on a page in the native UI. They are automatically created when you define an object and configured with a simple drag-and-drop layout tool.
Simplified Configuration Management
Configuration management is very different from what you might be accustomed to from on-premise development. Setting up a development environment is trivial with Force.com. You can provision a new development environment in a few clicks and deploy your code to it using the familiar Eclipse IDE.
When added to your Eclipse IDE or file system, Force.com code and metadata are ready to be committed to an existing source control system. Custom Ant tasks are available to automate your deployments. Sandboxes can be provisioned for testing against real-world volumes of data and users. They are automatically refreshed from snapshots of production data per your request. Force.com's packaging feature allows you to partition your code into logical units of functionality, making it easier to manage and share with others at your company or in the larger community.
Integrated Unit Testing
The ability to write and execute unit tests is a native part of the Apex language and Force.com development environment. Typically a test framework is an optional component that you need to integrate into your development and build process. With the facility to test aligned closely with code, writing and executing tests becomes a natural part of the development lifecycle rather than an afterthought.
In fact, unit tests are required by Force.com to deploy code into production. This applies to all Apex code in the system: user interface logic, triggers, and general business logic. To achieve the necessary 75% test coverage often requires as much if not more code than the actual Apex classes.
To make sure you don't code yourself into a corner without test coverage, a great time to write tests is while you code. Many development methodologies advocate test-driven development, and writing tests as you code has benefits well beyond simply meeting the minimum requirements for production deployment in Force.com. For example, a comprehensive library of tests adds guardrails to refactoring and maintenance tasks, steering you away from destabilizing changes.
Integrated Model-View-Controller (MVC) Pattern
The goal of the MVC pattern is maintainable user interface code. It dictates the separation of data, visual elements that represent data and actions to the user, and logic that mediates between the two. If these three areas are allowed to collide and the codebase grows large enough, the cost to fix bugs and add features becomes prohibitive.
Visualforce adopts MVC by design. For example, its view components do not allow the expression of business logic and vice versa. Like other best practices made mandatory by the platform, this can be inconvenient when you just want to do something quick and dirty. But it is there to help. After all, quick-and-dirty demos have an uncanny tendency to morph into production applications.
Integrated Interoperability
Force.com provides Web services support to your applications without code. You can designate an Apex method as a Web service. WSDL is automatically generated to reflect the method signature. Your logic is now accessible to any program that is capable of calling a Web service, given valid credentials for an authorized user in your organization. You can also restrict access by IP address or open up your service to guests.
As in other languages, Apex provides you with a WSDL-to-Apex tool. This tool generates Apex stubs from WSDL, enabling you to integrate with SOAP-enabled business processes existing outside of Force.com. Lower-level Apex libraries are also available for raw HTTP and XML processing.
End of Life
Retiring a production application requires a few clicks from the system administrator. Users can also be quickly removed or repurposed for other applications. Applications can be readily consolidated because they share the same infrastructure. For example, you might keep an old user interface online while a new one is being run in parallel, both writing to the same set of objects. Although these things are possible with other technologies, Force.com removes a sizable chunk of infrastructure complexity, preserving more intellectual bandwidth to devote to tackling the hard problems specific to your business.
Tools and Resources
Force.com has a rich developer ecosystem. There are discussion groups for reaching out to the development community on specific subjects, a source-code repository for open-source projects, a Web site called AppExchange where you can browse for free and paid extensions to the platform, services companies to help you plan and implement your larger projects, and Ideas, a site for posting your ideas for enhancing the platform.
The following subsections list some tools and resources that exist to make your projects successful.
Developer Force (http://developer.force.com)
Developer Force is a rich source of information on Force.com. It contains documentation, tutorials, e-books written by Salesforce, a blog, and a Wiki with links to many more resources inside and outside of Salesforce.
Developer Discussion Boards (http://community.salesforce.com)
This is a public discussion forum for the Force.com development community. It is divided into a dozen separate boards by technology area. Users post their questions and problems, gripes, and kudos. Other users in the community contribute answers and solutions, including Salesforce employees. The boards are a great way to build a reputation as a Force.com expert and keep current on the latest activity around the platform.
Ideas (http://ideas.salesforce.com)
If you have a suggestion for improving Force.com or any Salesforce product, visit the Ideas site and post it. Other users in the community can vote for it. If your idea is popular enough, it might be added to the next release of Force.com. Incidentally, Ideas is a reusable component of Force.com, so you can build your own customized idea-sharing sites.
Code Share (http://developer.force.com/codeshare)
Code Share is a directory of open-source code contributions from the Force.com community, with links to the actual source code hosted on Google Code. Salesforce employees have contributed many projects here. Two notable ones are the Facebook Toolkit, a library for integrating with Facebook, and XmlDom, an XML parsing library modeled after one in Java.
Platform Documentation
Salesforce provides documentation through online, context-sensitive help within the Web user interface, as well as HTML and PDF versions of its reference manuals. All documentation can be found at Developer Force.
AppExchange (www.appexchange.com)
AppExchange is a directory of ready-to-install applications developed on Force.com. The applications consist of metadata, such as Visualforce pages and Apex code, deployable into your Force.com environment. Users can rate applications from one to five stars and write reviews. There are many free applications written by Salesforce employees to illustrate new platform features. Commercial applications are also available for trial and purchase. AppExchange is how ISVs distribute their Force.com applications to customers.
Dreamforce
Salesforce has a series of user conferences every year called Dreamforce. San Francisco hosts the largest Dreamforce venue, with thousands attending to participate in training sessions, booths, product demos, keynote speeches, breakout sessions, executive briefings, and, of course, the parties. Dreamforce is a fun way to stay up to date with the technology.
Systems Integrators
For deployments including significant numbers of users, integration with other enterprise systems, or complex data migrations, consider contracting the services of a systems integrator. There are systems integrators who have competency with Force.com, SFA, SSS, and other Salesforce products. They include pure-play systems integrators such as Appirio or Model Metrics, as well as general consultancies like Accenture.
Technical Support
When you encounter undocumented or incorrect behavior in the system, submit a bug report. If the issue can be described simply, like a cryptic error message, search for it in the discussion groups. In many cases someone else has already run into the same problem before you, posted about it, and attracted the attention of Salesforce employees. If not, the ability to log and track Force.com platform support cases is available in Force.com's Web user interface.