This article does not intend to explain what an API is, what its various components are, or how to create one. Rather, we will focus on the problems that arise in the context of API-based architectures and discuss potential solutions.
In the realm of product development, there is a shift occurring from monolithic architectures to microservice-based architectures. This transition involves moving away from using a single technology and MVC architecture towards adopting API-based architectures, where both the front and back ends are developed using different technologies.
While this transition brings about numerous advantages, it also brings with it a considerable amount of responsibility.
The Problem
Security
The primary focus in API calls is on ensuring security. APIs expose the system to the external world, and if proper multi-level security measures are not implemented, there is a risk of compromising the entire system. While there are various methods available to implement security at different levels, the crucial factor in achieving security lies in the developers’ discipline to use the correct methods in the appropriate context.
The significance of security becomes much more imperative when APIs are exposed to the external world.
Documentation
The main reason for the failure of API implementations often stems from a lack of comprehensive and accurate documentation. Significant development cycles are laid out in the search for the correct API signature and its corresponding implementation.
Insufficient documentation also contributes to the occurrence of duplicated APIs over time. Removing such duplication becomes challenging, as no team is willing to assume responsibility for making changes in the running production system.
Versioning
Proper versioning of APIs is essential for effectively handling changes in business requirements, maintaining backward compatibility, and ensuring system stability.
The Solution
Security
Regardless of whether APIs are used internally or exposed to the public, it is crucial to maintain the same level of security. Several tools are available to assist developers in identifying vulnerabilities and even providing suggested solutions. Common issues such as SQL injection and cross-site scripting attacks can be detected using these tools. Incorporating the use of these tools to examine the code should be a mandatory step in the testing process.
Other security measures that need to be implemented are:
IP whitelisting: Allow API calls exclusively from restricted IPs. However, this approach may not always be feasible, especially for APIs provided by SaaS service providers that require access by a wide range of users.
Tokens: Generate short or long-lived tokens and regularly rotate them at predetermined intervals.
Other aspects to consider for better performance of APIs:
API call throttling: Implement limitations on the number of API calls per second or minute for each subscriber to effectively handle the workload.
Conditions in API requests:Â Ensure that conditions specified in API requests do not result in the retrieval of excessive data, which could potentially impede operations and slow down network performance.
Timeout: APIs should return results within a specified timeframe. Failure to do so may lead to resource blocking and affect the performance of the system. Thus, it is essential to implement appropriate timeouts to terminate API calls and free the resources accordingly.
Documentation
Proper and clear documentation solves many API integration problems. Several third-party tools, such as Rdoc for Ruby, Document360, Swagger, etc., are available to create this documentation. Apart from documentation, each tool offers various functionalities, including code snippets in different languages, API testing options, and more.
The development team should carefully select the appropriate tool and follow the guidelines provided by that tool. This approach ensures that the API is documented with enhanced clarity, leveraging the capabilities of the chosen tool.
Versioning
Software applications are never static. They undergo numerous changes, including bug fixes, updates to requirements or business policies, and the addition of new features. These changes can be categorized into two types: incremental and breaking changes. In the case of breaking changes, all API users must make adjustments to accommodate the modifications. However, for incremental changes, users have the flexibility to decide whether to implement them or not, which introduces the concept of versioning in APIs.
It is crucial to appropriately version all such changes to ensure backward compatibility. Additionally, comprehensive documentation is important to provide clarity regarding the differences between each version.
Conclusion
APIs have become instrumental in the digital landscape, and their popularity is expected to skyrocket, resulting in a vast array of APIs floating around on the internet. In today’s world, the majority of products and services operate on the XaaS (SaaS, PaaS, etc.) model, and their APIs are open to the public. This, thereby, calls for more strict rules and processes around API development to avoid the issues mentioned earlier.