Book Image

Spring 5.0 By Example

By : Claudio Eduardo de Oliveira
Book Image

Spring 5.0 By Example

By: Claudio Eduardo de Oliveira

Overview of this book

With growing demands, organizations are looking for systems that are robust and scalable. Therefore, the Spring Framework has become the most popular framework for Java development. It not only simplifies software development but also improves developer productivity. This book covers effective ways to develop robust applications in Java using Spring. The book has three parts, where each one covers the building of a comprehensive project in Java and Spring. In the first part, you will construct a CMS Portal using Spring's support for building REST APIs. You will also learn to integrate these APIs with AngularJS and later develop this application in a reactive fashion using Project Reactor, Spring WebFlux, and Spring Data. In the second part, you’ll understand how to build a messaging application, which will consume the Twitter API and perform filtering and transformations. Here, you will also learn about server-sent events and explore Spring’s support for Kotlin, which makes application development quick and efficient. In the last part, you will build a real microservice application using the most important techniques and patterns such as service discovery, circuit breakers, security, data streams, monitoring, and a lot more from this architectural style. By the end of the book, you will be confident about using Spring to build your applications.
Table of Contents (17 chapters)
Title Page
Copyright and Credits
Dedication
Packt Upsell
Contributors
Preface
Index

Testing APIs


Our container is running. Now, we can try to call the APIs to check the behaviors. In this part, we will use the curl command line. The curl allows us to call APIs by the command line on Linux. Also, we will use jq to make the JSON readable on the command line, if you do not have these, look at the Tip Box to install these tools.

Let's call our create API, remember to create we can use the POST method in the base path of API. Then type the following command:

curl -H "Content-Type: application/json" -X POST -d '{"hashTag":"java","queue":"java"}' \
 http://localhost:9090/api/tracked-hash-tag

There are interesting things here. The -H argument instructs curl to put it in the request headers and -d indicates the request body. Moreover, finally, we have the server address.

We have created the new tracked-hash-tag. Let's check our GET API to obtain this data:

curl 'http://localhost:9090/api/tracked-hash-tag' | jq '.'

Awesome, we called the curl tool and printed the JSON value with the jq...