This quick start walks through using both the server and the client of Spring Cloud Config Server.
First, start the server, as follows:
$ cd spring-cloud-config-server $ ../mvnw spring-boot:run
The server is a Spring Boot application, so you can run it from your IDE if you prefer to do so (the main class is ConfigServerApplication).
Next try out a client, as follows:
$ curl localhost:8888/foo/development
{
"name": "foo",
"profiles": [
"development"
]
....
"propertySources": [
{
"name": "https://github.com/spring-cloud-samples/config-repo/foo-development.properties",
"source": {
"bar": "spam",
"foo": "from foo development"
}
},
{
"name": "https://github.com/spring-cloud-samples/config-repo/foo.properties",
"source": {
"foo": "from foo props",
"democonfigclient.message": "hello spring io"
}
},
....
The default strategy for locating property sources is to clone a git repository (at spring.cloud.config.server.git.uri) and use it to initialize a mini SpringApplication.
The mini-application’s Environment is used to enumerate property sources and publish them at a JSON endpoint.
The HTTP service has resources in the following form:
/{application}/{profile}[/{label}]
/{application}-{profile}.yml
/{label}/{application}-{profile}.yml
/{application}-{profile}.properties
/{label}/{application}-{profile}.properties
For example:
curl localhost:8888/foo/development curl localhost:8888/foo/development/master curl localhost:8888/foo/development,db/master curl localhost:8888/foo-development.yml curl localhost:8888/foo-db.properties curl localhost:8888/master/foo-db.properties
where application is injected as the spring.config.name in the SpringApplication (what is normally application in a regular Spring Boot app), profile is an active profile (or comma-separated list of properties), and label is an optional git label (defaults to master.)
Spring Cloud Config Server pulls configuration for remote clients from various sources. The following example gets configuration from a git repository (which must be provided), as shown in the following example:
spring:
cloud:
config:
server:
git:
uri: https://github.com/spring-cloud-samples/config-repoOther sources are any JDBC compatible database, Subversion, Hashicorp Vault, Credhub and local filesystems.
Client Side Usage
To use these features in an application, you can build it as a Spring Boot application that depends on spring-cloud-config-client (for an example, see the test cases for the config-client or the sample application).
The most convenient way to add the dependency is with a Spring Boot starter org.springframework.cloud:spring-cloud-starter-config.
There is also a parent pom and BOM (spring-cloud-starter-parent) for Maven users and a Spring IO version management properties file for Gradle and Spring CLI users. The following example shows a typical Maven configuration:
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>{spring-boot-docs-version}</version>
<relativePath /> <!-- lookup parent from repository -->
</parent>
<dependencyManagement>
<dependencies>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-dependencies</artifactId>
<version>{spring-cloud-version}</version>
<type>pom</type>
<scope>import</scope>
</dependency>
</dependencies>
</dependencyManagement>
<dependencies>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-config</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<scope>test</scope>
</dependency>
</dependencies>
<build>
<plugins>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
</plugin>
</plugins>
</build>
<!-- repositories also needed for snapshots and milestones -->Now you can create a standard Spring Boot application, such as the following HTTP server:
@SpringBootApplication
@RestController
public class Application {
@RequestMapping("/")
public String home() {
return "Hello World!";
}
public static void main(String[] args) {
SpringApplication.run(Application.class, args);
}
}
When this HTTP server runs, it picks up the external configuration from the default local config server (if it is running) on port 8888.
To modify the startup behavior, you can change the location of the config server by using application.properties as shown in the following example:
spring.config.import=optional:configserver:http://myconfigserver.com
By default, if no application name is set, application will be used. To modify the name, the following property can be added to the application.properties file:
spring.application.name: myapp
When setting the property ${spring.application.name} do not prefix your app name with the reserved word application- to prevent issues resolving the correct property source.
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The Config Server properties show up in the /env endpoint as a high-priority property source, as shown in the following example.
$ curl localhost:8080/env
{
"activeProfiles": [],
{
"name": "servletContextInitParams",
"properties": {}
},
{
"name": "configserver:https://github.com/spring-cloud-samples/config-repo/foo.properties",
"properties": {
"foo": {
"value": "bar",
"origin": "Config Server https://github.com/spring-cloud-samples/config-repo/foo.properties:2:12"
}
}
},
...
}
A property source called configserver:<URL of remote repository>/<file name> contains the foo property with a value of bar.
| The URL in the property source name is the git repository, not the config server URL. |
If you use Spring Cloud Config Client, you need to set the spring.config.import property in order to bind to Config Server. You can read more about it in the Spring Cloud Config Reference Guide.
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