APIs (application program interfaces) and microservices have become integral to any business that interacts either internally or externally or both on a service or application level. These terms are relatively new, with API first being used in the year 2000 and microservice in 2011.
The API and microservice industries are growing at a fast pace. The global API management market is expected to reach $5.1 billion by 2023, rising from $1.2 billion in 2018, according to MarketsAndMarketsOpens a new window . Microservices also are growing rapidly. ResearchAndMarkets forecastsOpens a new window that the cloud microservices market will reach $1,880.0 million by 2023 from $683.2 million in 2018. Now, lets examine what APIs and microservices are and how they can be beneficial to organisations.
Down to the brass tacks
The adoption of microservices and APIs has been on the rise because these technologies allow for greater flexibility besides helping organisations deliver high quality services. Microservices are small, independently working components of application development that are assembled together to create a full service. Each microservice is autonomous, self-contained and is responsible for a single capability. This is where APIs come in. APIs are the vehicles for communication between different microservices. They allow microservices to share data, direct input and output, and create reportsamong other things. However, it should be noted that like with any other technology, there are a few challenges associated with APIs and microservices. An organisation should, therefore, undertake thorough due diligence before investing in these projects.
Classification
There are various types of APIs: Public APIs, Partner APIs, and Internal APIs. Public APIs have no restrictions and are available to the public. Partner APIs restrict access to those who need them. Lastly, the internal APIs are private APIs and are generally used behind the scenes (or internally) by an organisations development teams.
Additionally, APIs are categorized as simple object access protocol (SOAP), remote procedure call (RPC), and representational state transfer (REST or RESTful). SOAP APIs use lower-level protocols like HTTP to communicate between a services shared elements. RPC APIs are mainly used in client-server models and allow a program to request a service without compromising network details. REST, the most popular API type, can be used with nearly any protocol including HTTP.
Microservices are classified into two types: stateful and stateless. Stateful microservices save session information within the code. They are suitable for transactions that require more than one database, such as interactive gaming. Stateless microservices do not retain the session state between requests. They do not link requests in the way that stateful microservices do. Stateless microservices are used for transactions that return specific results, such as checking a mobile services prepaid balance using a USSR code.
The advantages
APIs and microservices have become popular due to the rigidity and complexities that monolithic legacy applications impose. In a monolithic setup, small changes or new services would take several weeks if not months to implement into an existing service. Even traditional methods like enterprise service bus (ESB) and service-oriented architecture (SOA) are laden with complexities and long development cycles. In an Internet-driven world, where speed is the primary differentiator, companies cannot afford to waste time waiting to introduce new services and products. APIs and microservices allow teams to quickly develop new services and get features out easily. Microservices and APIs also allow teams to break down old systems into task-specific modules. A few advantages are common to both, microservices and APIs. Lets explore these first.
Modularity: Legacy applications are largely rigid monoliths that require intensive development and time. They often lead to applications clogging server resources and slowing down performance. Costly hardware upgrades are often essential to minimise performance dips. APIs and microservices allow developers to build tiny componentsfeatures or servicesin a staggered, modular fashion. As elements are built autonomously, the entire development project can be agile.
Modularity offers another advantage. As the pieces under development are decoupled from each other, developers dont have to acquire insights into the entire application ecosystem. They can concentrate on the task assigned to them and just do what they are skilled at.
Parallel development and continuous rollout: Modular development ensures that APIs and microservices can be developed and tested in parallel. For instance, the UI-UX designers can create their interfaces while the software backend is developed simultaneously. A continuous rollout of new APIs and microservices can be achieved as components are developed, tested, modified, and monitored in parallel.
Reusability: Since microservices and APIs are typically combinations of multiple elements, an organisation can create a library of elements that can be reused later delivering time and cost savings to any organisation.
Technological diversity: Development teams can employ a variety of programming languages, tools and frameworks guided by the specific needs of services being developed. This way, organisations can reap the inherent benefits of various technologies.
APIs deliver two additional benefits:
Rapid business expansion: APIs not only help companies to integrate their internal systems but also connect with external platforms and third-party databases and services. Aadhaar authentication is a good example of how telecom companies have been able to securely access Aadhaar database with APIs to quickly add new customers.
Freedom: Traditionally, business applications came with their own protocols, data formats, and data management methods. APIs, on the contrary, leverage widely used web protocols such as TCP and HTTP, eliminating the need to be dictated by proprietary formats. With APIs, services can be developed and consumed in an easy, plug-in, plug-out fashion.
Lastly, both these technologies offer immense business benefits to organisations, especially in todays context in which technologies like the cloud, social media, mobility, AI, and IoT offer new possibilities of growth and expansion to organisations.