A robust application programming interface (API) has become essential for today’s successful SaaS independent software vendors (ISVs). As a SaaS vendor, you should expect that a majority of your customers are going to require interoperability with other SaaS applications, web services, and legacy systems. As demonstrated by internet pioneers Google, Amazon, and Facebook, an open application strategy facilitates deeper customer usage and enables new revenue streams. Integration is critical for SaaS vendors, and developing a reliable API strategy is the first step toward achieving that goal.
After reviewing hundreds of actual SaaS APIs, many up to par and others distinctly subpar, it is clear that there are a number of common mistakes made when developing an API. Fortunately, each of them can be easily remedied by following best practices.
1. Exposing operations instead of objects
2. Assuming a WSDL contains everything necessary to describe your API
3. Developing a single version of your API which changes with each release of your SaaS application
4. Never batching or throttling the results of query calls against your API
5. Maintaining separate schemas for adding, updating, or removing your Customer object
… + more … The Top 10 Most Common API Pitfalls