spring-cloud-etcd is no longer actively maintained by VMware, Inc.
This project provides Etcd integrations for Spring Boot apps through autoconfiguration and binding to the Spring Environment and other Spring programming model idioms. With a few simple annotations you can quickly enable and configure the common patterns inside your application and build large distributed systems with Etcd based components. The patterns provided include Service Discovery, Circuit Breaker and Configuration. Intelligent Routing (Zuul) and Client Side Load Balancing (Ribbon) are provided by integration with Spring Cloud Netflix.
Etcd overview
Features of Etcd
-
Distributed configuration
-
Service registration and discovery
See the overview for more information.
Spring Cloud Etcd Features
-
Spring Etcd
DiscoveryClient
implementation-
supports Ribbon and Zuul
-
-
Etcd based
PropertySource
loaded during the 'bootstrap' phase.
Running the sample
-
Run
./src/main/bash/run_etcd.sh
-
verify etcd is running by visiting http://localhost:4001/version
-
run
mvn --settings .settings.xml package
this will bring in the required spring cloud maven repositories and build -
run
java -jar spring-cloud-etcd-sample/target/spring-cloud-etcd-sample-1.0.0.BUILD-SNAPSHOT.jar
-
visit http://localhost:8080, verify that
{"serviceId":"<yourhost>:8080","host":"<yourhost>","port":8080}
results -
run
java -jar spring-cloud-etcd-sample/target/spring-cloud-etcd-sample-1.0.0.BUILD-SNAPSHOT.jar --server.port=8081
-
visit http://localhost:8080 again, verify that
{"serviceId":"<yourhost>:8081","host":"<yourhost>","port":8081}
eventually shows up in the results in a round robbin fashion (may take a minute or so).
Building
Basic Compile and Test
To build the source you will need to install Apache Maven v3.0.6 or above and JDK 1.7.
Spring Cloud uses Maven for most build-related activities, and you should be able to get off the ground quite quickly by cloning the project you are interested in and typing
$ mvn install -s .settings.xml
Note
|
You may need to increase the amount of memory available to Maven by setting
a MAVEN_OPTS environment variable with the value -Xmx512m -XX:MaxPermSize=128m
|
The .settings.xml
is only required the first time (or after updates
to dependencies). It is there to provide repository declarations so
that those do not need to be hard coded in the project poms.
For hints on how to build the project look in .travis.yml
if there
is one. There should be a "script" and maybe "install" command. Also
look at the "services" section to see if any services need to be
running locally (e.g. mongo or rabbit). Ignore the git-related bits
that you might find in "before_install" since they will be able git
credentials and you already have those.
If you need mongo, rabbit or redis, see the README in the scripts demo repository for instructions. For example consider using the "fig.yml" with Fig to run them in Docker containers.
Documentation
The spring-cloud-build module has a "docs" profile, and if you switch
that on it will try to build asciidoc sources from
src/main/asciidoc
. As part of that process it will look for a
README.adoc
and process it by loading all the includes, but not
parsing or rendering it, just copying it to ${main.basedir}
(defaults to ${basedir}
, i.e. the root of the project). If there are
any changes in the README it will then show up after a Maven build as
a modified file in the correct place. Just commit it and push the change.
Working with the code
If you donβt have an IDE preference we would recommend that you use Spring Tools Suite or Eclipse when working with the code. We use the m2eclipe eclipse plugin for maven support. Other IDEs and tools should also work without issue.
Importing into eclipse with m2eclipse
We recommend the m2eclipe eclipse plugin when working with eclipse. If you donβt already have m2eclipse installed it is available from the "eclipse marketplace".
Importing into eclipse without m2eclipse
If you prefer not to use m2eclipse you can generate eclipse project metadata using the following command:
$ mvn eclipse:eclipse
The generated eclipse projects can be imported by selecting import existing projects
from the file
menu.
Adding Project Lombok Agent
Spring Cloud uses [Project Lombok](http://projectlombok.org/features/index.html) to generate getters and setters etc. Compiling from the command line this shouldnβt cause any problems, but in an IDE you need to add an agent to the JVM. Full instructions can be found in the Lombok website. The sign that you need to do this is a lot of compiler errors to do with missing methods and fields, e.g.
The method getInitialStatus() is undefined for the type EurekaInstanceConfigBean EurekaDiscoveryClientConfiguration.java /spring-cloud-netflix-core/src/main/java/org/springframework/cloud/netflix/eureka line 120 Java Problem The method getInitialStatus() is undefined for the type EurekaInstanceConfigBean EurekaDiscoveryClientConfiguration.java /spring-cloud-netflix-core/src/main/java/org/springframework/cloud/netflix/eureka line 121 Java Problem The method setNonSecurePort(int) is undefined for the type EurekaInstanceConfigBean EurekaDiscoveryClientConfiguration.java /spring-cloud-netflix-core/src/main/java/org/springframework/cloud/netflix/eureka line 112 Java Problem The type EurekaInstanceConfigBean.IdentifyingDataCenterInfo must implement the inherited abstract method DataCenterInfo.getName() EurekaInstanceConfigBean.java /spring-cloud-netflix-core/src/main/java/org/springframework/cloud/netflix/eureka line 131 Java Problem The method getId() is undefined for the type ProxyRouteLocator.ProxyRouteSpec PreDecorationFilter.java /spring-cloud-netflix-core/src/main/java/org/springframework/cloud/netflix/zuul/filters/pre line 60 Java Problem The method getLocation() is undefined for the type ProxyRouteLocator.ProxyRouteSpec PreDecorationFilter.java /spring-cloud-netflix-core/src/main/java/org/springframework/cloud/netflix/zuul/filters/pre line 55 Java Problem
Importing into other IDEs
Maven is well supported by most Java IDEs. Refer to you vendor documentation.
Contributing
Spring Cloud is released under the non-restrictive Apache 2.0 license, and follows a very standard Github development process, using Github tracker for issues and merging pull requests into master. If you want to contribute even something trivial please do not hesitate, but follow the guidelines below.
Sign the Contributor License Agreement
Before we accept a non-trivial patch or pull request we will need you to sign the contributorβs agreement. Signing the contributorβs agreement does not grant anyone commit rights to the main repository, but it does mean that we can accept your contributions, and you will get an author credit if we do. Active contributors might be asked to join the core team, and given the ability to merge pull requests.
Code Conventions and Housekeeping
None of these is essential for a pull request, but they will all help. They can also be added after the original pull request but before a merge.
-
Use the Spring Framework code format conventions. If you use Eclipse you can import formatter settings using the
eclipse-code-formatter.xml
file from the Spring Cloud Build project. If using IntelliJ, you can use the Eclipse Code Formatter Plugin to import the same file. -
Make sure all new
.java
files to have a simple Javadoc class comment with at least an@author
tag identifying you, and preferably at least a paragraph on what the class is for. -
Add the ASF license header comment to all new
.java
files (copy from existing files in the project) -
Add yourself as an
@author
to the .java files that you modify substantially (more than cosmetic changes). -
Add some Javadocs and, if you change the namespace, some XSD doc elements.
-
A few unit tests would help a lot as wellβββsomeone has to do it.
-
If no-one else is using your branch, please rebase it against the current master (or other target branch in the main project).
-
When writing a commit message please follow these conventions, if you are fixing an existing issue please add
Fixes gh-XXXX
at the end of the commit message (where XXXX is the issue number).