Search results for: Open API

In this tutorial, you will learn how to implement the API Gateway Lambda Authorizer in Java. You will also learn how to make Lambda Authorizer validate Authorization JWT. First, we will create an API using API Gateway then we will make lambda function as an integration point for the GET method of our resource. After…

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In the previous blog post, we covered the basics of how to use Keycloak with Spring boot. In this blog post, we will explore Role-based Access Control to Rest API with Keycloak. So let’s get started! Imagine we have a microservice for a Research Journal Management System that can serve users with two types of…

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In this tutorial, we are going to see how we can use the AWS API Gateway as a trigger to an AWS Lambda function. This tutorial requires you to be familiar with building and deploying Serverless Applications with AWS Lambda. Prerequisite: Build and Deploy a Serverless Spring Boot Web Application with AWS Lambda Firstly, add…

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This tutorial is the fifth in a series on Reactive Programming in Java and Spring Framework. In this tutorial, we will develop a simple REST API using Spring Web flux. To completely understand this tutorial, it is better to read a previous tutorial first. It would also help to know how to develop a REST Controller using…

Read More Developing a REST API using Spring WebFlux

class Test { public static void main(String[] args) { System.out.println(“Normal Stream…”); IntStream integers = IntStream.rangeClosed(1, 10); integers.forEach(num -> System.out.print(num + ” “)); System.out.println(); System.out.println(“Parallel Stream…”); IntStream integers2 = IntStream.rangeClosed(1, 10); integers2.parallel().forEach(num -> System.out.print(num + ” “)); } } Output: Normal Stream… 1 2 3 4 5 6 7 8 9 10 Parallel Stream… 7 6…

Read More Introduction to Parallel Streams API in Java

This tutorial will teach you how to create a simple Spring Cloud API Gateway Global Pre-filter and Post-filter classes. Global filters are executed for every route defined in the API Gateway. The main difference between the pre-filter and post-filter classes is that the pre-filter code is executed before Spring Cloud API Gateway routes the request to a…

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One way to ensure that an HTTP request to a web service endpoint contains an Authorization JWT token is to configure a gateway route to require an Authorization header.  If the HTTP request does not contain an Authorization header, Spring Cloud API Gateway will not even route this request to a destination microservice. We can…

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This tutorial will teach you how to configure your Spring Cloud API Gateway to automatically create routes based on services registered with discovery clients like Eureka, Consul, or Zookeeper. For a step-by-step series of video lessons, please check this page: Spring Boot Microservices and Spring Cloud. Enable Discovery Locator A quick way to enable Spring Cloud…

Read More Spring Cloud API Gateway Automatic Mapping of Routes

If a requested Microservice takes long time to respond, Zuul Api Gateway might timeout and a Gateway timeout error will take place. { “timestamp”: “2019-05-24T00:53:22.152+0000”, “status”: 504, “error”: “Gateway Timeout”, “message”: “com.netflix.zuul.exception.ZuulException: Hystrix Readed time out” } In this short blog post I am going to share with you how to make your Zuul Api…

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