Use of the Spring Cloud Config Distributed Configuration Center and the pits encountered

Distributed Configuration Center

Why should I use the Distributed Configuration Center thing? Now this micro-service army has covered a variety of large and small enterprises, each service granularity is relatively small, so there will be a large number of services in the system, each service must have their own configuration information, or the same configuration information, there may be different environments each service also has a separate set of configurations, this situation is a large number of configuration files, It's quite laborious to maintain, for a chestnut:
In the process of development, the general database is the development environment database, all services DB IP configuration is: 92.168.0.1, suddenly boss said, development environment changed, DB IP to modify, this is not easy, all modules change the configuration of the DB, asked you uncomfortable not uncomfortable?
This time the distributed configuration Center has played a great advantage, only need to modify the configuration center configuration, all services can be automatically effective, cool uncomfortable!

Spring Cloud Config

Website address: http://cloud.spring.io/spring-cloud-config/

Brief introduction

Spring Cloud ConfigProvides external configuration support for distributed systems for both the server and the client. The configuration server provides a centralized external configuration for all environments for each application. It implements mapping of server and client pairs Spring Environment and PropertySource abstractions, so it can be used in applications that run in any other language, except for applications that are built by spring. As an application that can be tested or put into production by deploying pipelines, we can create configurations for these environments separately, and get the configuration of the corresponding environment to run when the environment needs to be migrated.

By default, the server uses GIT to store configuration information, which facilitates versioning of the environment configuration and provides easy management and access to configuration content through the GIT client tool. Of course he also provides a way to store localized file systems.

Use spring Cloud for centralized configuration management, remove previous configuration files from your project and put them centrally managed in Git or SVN, and notify applications when changes are needed, without restarting the application refresh configuration.

Implementation principle

In fact, the implementation of the principle is relatively simple, based on Git interactive operation.

1. We put the config file on git.
2. Spring Cloud Config Hub service connects to Git
3. The client needs to configure configuration information from the Configuration Center service to obtain
4. When the client starts, it gets the configuration information from the configuration Center on Git

Configure the Hub service side

Pom.xml adding dependencies

<dependencies>    <dependency>        <groupId>org.springframework.cloud</groupId>        <artifactId>spring-cloud-config-server</artifactId>    </dependency></dependencies><dependencyManagement>    <dependencies>        <!-- spring cloud -->        <dependency>            <groupId>org.springframework.cloud</groupId>            <artifactId>spring-cloud-dependencies</artifactId>            <version>Edgware.SR3</version>            <type>pom</type>            <scope>import</scope>        </dependency>    </dependencies></dependencyManagement>

Application Start class Add annotations

@EnableConfigServerto add annotations, enable the configuration center:

package com.qianxunclub;import org.springframework.boot.SpringApplication;import org.springframework.boot.autoconfigure.SpringBootApplication;import org.springframework.cloud.config.server.EnableConfigServer;/*** @author chihiro.zhang*/@SpringBootApplication@EnableConfigServerpublic class Application {    public static void main(String[] args) {        SpringApplication.run(Application.class, args);    }}

Configuration file

In application.yml or application.properties add configuration information:

spring:  cloud:    config:      server:        git:          uri: https://gitee.com/qianxunclub/spring-boot-config-repo          default-label: master          search-paths: /**          basedir: target/config

• Spring.cloud.config.server.git.uri: Configuring the Git repository address
• Spring.cloud.config.server.git.search-paths: Repository folder directory, if yes /** , all files in all directories
• Spring.cloud.config.server.git.default-label: Configuring a branch of a warehouse
• Spring.cloud.config.server.git.basedir: Configuration file pulled to local directory location

Start test

First, add a application-dev.yml configuration file to git with the following:

test: 我是配置中心配置信息

has been configured to complete, start a wave test, see how it works, normally it can start normally, and then get the configuration file try
Access Address: Http://localhost:8888/test/dev
If you return the following, it is successful:

{    "name":"test",    "profiles":[        "dev"    ],    "label":null,    "version":"64e7882a8f280641724e454a2db5a3da7b44d3d4",    "state":null,    "propertySources":[        {            "name":"https://gitee.com/qianxunclub/spring-boot-config-repo/application-dev.yml",            "source":{                "test":"配置中心的配置信息"            }        }    ]}

The HTTP request address and resource file mappings are as follows:

• /{application}/{profile}[/{label}]
• /{application}-{profile}.yml
• /{label}/{application}-{profile}.yml
• /{application}-{profile}.properties
• /{label}/{application}-{profile}.properties

Configure the Hub client to use

Pom.xml adding dependencies

<dependencies>    <dependency>        <groupId>org.springframework.cloud</groupId>        <artifactId>spring-cloud-starter-config</artifactId>    </dependency></dependencies><dependencyManagement>    <dependencies>        <!-- spring cloud -->        <dependency>            <groupId>org.springframework.cloud</groupId>            <artifactId>spring-cloud-dependencies</artifactId>            <version>Edgware.SR3</version>            <type>pom</type>            <scope>import</scope>        </dependency>    </dependencies></dependencyManagement>

Configuration file

Create a bootstrap.yml file, remember, is a bootstrap.yml file bootstrap.yml file, I wrote to application.yml this inside, a variety of problems Ah, add the following configuration:

spring:  cloud:    config:      name: application      profile: dev      label: master      uri: http://localhost:8888/

• Spring.cloud.config.label: Indicates the branch of the remote repository
• Spring.cloud.config.profile: Specify different environment profiles, and the corresponding git repositories application-dev.yml
  
• Spring.cloud.config.name: Configuration name, General and git repository application-dev.yml correspondence
• Spring.cloud.config.uri: The Configuration Center service address above

Start test

First, add a class that gets the configuration information:

/** * @author chihiro.zhang */@Configuration@EnableAutoConfigurationpublic class DemoConfiguration {    @Value("${test}")    private  String test;}

Find a place to call, output this test, will print the above git configuration information, cool not!

Tell me about the hole in the middle.

1. Server-side git configuration can't get git repository configuration file anyway

spring:    cloud:        config:        server:            git:                uri: https://gitee.com/qianxunclub/spring-boot-config-repo                default-label: master                search-paths: /**                basedir: target/config

At that time this uri configuration is the company's Git repository, the company's Git repository access is required to open an agent to have access to the agent has opened, but has been error:

Whitelabel Error PageThis application has no explicit mapping for /error, so you are seeing this as a fallback.Wed Jun 06 11:10:56 CST 2018There was an unexpected error (type=Not Found, status=404).Cannot clone or checkout repository: http://xxx.com:5080/framework/config-repo

Very depressed, do not know why, but just, just, write blog time, have tested a bit, pass the ... Day the dog, do not know what reason, and so on the study came out to add.

1. Client configuration must be configured on the bootstrap.yml inside
   uriThe address that the port is called by default 8888http://localhost:8888/
   When started, it will be loaded label and uri , profile configuration, can be added in the profile startup parameters, can profile also be added in application.yml the
   nameYou can also application.yml add a

Demo

Configuration Center service side: Https://gitee.com/qianxunclub/qianxunclub-springboot-config
Configure Git repository: https://gitee.com/qianxunclub/qianxunclub-springboot-config
Configure client use: Https://gitee.com/qianxunclub/qianxunclub-starter-demo
Client main configuration in: Https://gitee.com/qianxunclub/qianxunclub-starter-parent/tree/master/qianxunclub-starter-config

Use of the Spring Cloud Config Distributed Configuration Center and the pits encountered