HOW TO : Configure maven to work with a proxy server

We ran into an issue at work recently, when trying to deploy a spring boot based micro service. The application included some libraries that were downloaded by the application using maven during runtime.

The environment that this application was running in had controlled access to the Internet. We configured the jvm parameters using the following parameters

-Dhttp.useProxy=true -Dhttp.proxyHost=PROXY_SERVER_NAME -Dhttp.proxyPort=xxxx

when running the application, we were getting failed dependency errors that stated something like this

Caused by: org.eclipse.aether.resolution.ArtifactResolutionException: Could not transfer artifact com.xxxxx.boot:xxxx
-boot-autoconfigure:pom:0.0.1-SNAPSHOT from/to central (http://repo1.maven.org/maven2/): Connection refused at org.eclipse.aether.internal.impl.DefaultArtifactResolver.resolve(DefaultArtifactResolver.java:444) at org.eclipse.aether.internal.impl.DefaultArtifactResolver.resolveArtifacts(DefaultArtifactResolver.java:246) at org.eclipse.aether.internal.impl.DefaultArtifactResolver.resolveArtifact(DefaultArtifactResolver.java:223) at org.apache.maven.repository.internal.DefaultArtifactDescriptorReader.loadPom(DefaultArtifactDescriptorReader.java:334)

Lot of head scratching, because the server running the application had connection to the proxy server and the JVM parameters were accurate.

Finally, we figured out Maven doesn’t use the JVM startup parameters and had to have proxy access configured specifically. There are two ways to do this

  • Add an environment variable called “MAVEN_OPTS” and pass the proxy server settings.. something like this
set MAVEN_OPTS= -Dhttp.proxyHost=PROXY_SERVER_NAME -Dhttp.proxyPort=xxxx
  • Configure the proxy server settings in Maven’s settings.xml… something like this
 <proxies>
 <proxy>
 <id>genproxy</id>
 <active>true</active>
 <protocol>http</protocol>
 <!--username>proxyuser</username-->
 <!--password>proxypass</password-->
 <host>myproxy.mycompany.com</host>
 <port>8080</port>
 <nonProxyHosts>*.mycompany.com|127.0.0.1</nonProxyHosts>
 </proxy>
 </proxies>