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modify last commit message.
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Install the prerequisites:
sudo yum install yum-utils
To set up the yum repository, create the file named
/etc/yum.repos.d/nginx.repowith the following contents:
name=nginx stable repo
name=nginx mainline repo
Spring Cloud Stream is a framework for building highly scalable event-driven microservices connected with shared messaging systems.
The framework provides flexible programming model built on already established and familiar Spring idioms and best practices, including support for persistent pub/sub semantics, consumer groups, and stateful partitions.
ZooKeeper is a high-performance coordination service for distributed applications. It exposes common services - such as naming, configuration management, synchronization, and group services - in a simple interface so you don’t have to write them from scratch. You can use it off-the-shelf to implement consensus, group management, leader election, and presence protocols. And you can build on it for your own, specific needs.
Start a Zookeeper container.
docker run -d --name zookeeper --restart always -p 2181:2181 zookeeper
Consul is a service mesh solution providing a full featured control plane with service discovery, configuration, and segmentation functionality. Each of these features can be used individually as needed, or they can be used together to build a full service mesh. Consul requires a data plane and supports both a proxy and native integration model. Consul ships with a simple built-in proxy so that everything works out of the box, but also supports 3rd party proxy integrations such as Envoy.
The key features of Consul includes Service Discovery, Health Checking, KV Store, Secure Service Communication and Multi Datacenter.
Spring Cloud Sleuth implements a distributed tracing solution for Spring Cloud, borrowing heavily from Dapper, Zipkin and HTrace. For most users Sleuth should be invisible, and all your interactions with external systems should be instrumented automatically. You can capture data simply in logs, or by sending it to a remote collector service.
With the help of Spring Cloud Sleuth, you can easily trace how a specified request getting through several different services in your system, which is impossible just using simple ELK stack.
“ELK” is the acronym for three open source projects: Elasticsearch, Logstash, and Kibana. Elasticsearch is a search and analytics engine. Logstash is a server‑side data processing pipeline that ingests data from multiple sources simultaneously, transforms it, and then sends it to a “stash” like Elasticsearch. Kibana lets users visualize data with charts and graphs in Elasticsearch.
The Elastic Stack is the next evolution of the ELK Stack.
For this post, we will use just ELK Stack, which is popular for log aggregation and efficient searching.
Hooks are a new addition in React 16.8 (React Native 0.59). It allows you hook into the internal magic of React, using state and other React features without writing a class. The main benefit is that you can write code that is shorter and easier to understand, and you can reuse stateful logic across components.
Today, we are going to see a couple of examples about React Hooks.
Spring Cloud Gateway is built on Spring Framework 5, Project Reactor and Spring Boot 2.0. It provides a simple way to route to APIs and provides cross cutting concerns to them such as: security, monitoring/metrics, and resiliency.
To include Spring Cloud Gateway in your project, use the following starter,