A web service is a communication mechanism defined between different computer systems. Without web services, custom peer-to-peer communication becomes cumbersome and platform specific. It is like a hundred different kinds of things that the web needs to understand and interpret. If computer systems align with the protocols that the web can understand easily, it is a great help.
A web service is a software system designed to support interoperable machine-to-machine interaction over a network, World Wide Web Consortium (W3C), https://www.w3.org/TR/ws-arch/.
Now, in simple words, a web service is a road between two endpoints where messages are transferred smoothly. Here, this transfer is usually one way. Two individual programmable entities can also communicate with each other through their own APIs. Two people communicate through language. Two applications communicate through the Application Programming Interface (API).
The reader might be wondering; what is the importance of the API in the current digital world? The rise of the Internet of Things (IoT) made API usage heavier than before. Consciousness about the API is growing day by day, and there are hundreds of APIs that are being developed and documented all over the world every day. Notable major businesses are seeing futures in the API as a Service (AAAS). A bright example is Amazon Web Services (AWS). It is a huge success in the cloud world. Developers write their own applications using the REST API provided by the AWS.
A few more hidden use cases are from travel sites like Ibibo and Expedia, which fetch real-time prices by calling the APIs of third-party gateways and data vendors. Web services are often charged these days.
Topics to be covered in this chapter are:
- The different Web Services available
- Representational State Transfer (REST) architecture in detail
- Introduction to Single Page Applications (SPA) with REST
- Setting up a Go project and running a development server
- Building our first service for finding Roman numerals
- Using Gulp to auto-compile Go code
