only load a plugin once from the classpath

Today, when loading plugins from the classpath we take the enumeration
given to us by the classloader and attempt to load every URL. This can
cause issues as certain classloaders, such as groovy's, will return the same
URL multiple times in the enumeration. When this happens, startup can fail
with guice errors as bindings have already been registered.

To workaround this, we create a set from the URLs returned by the classloader
to provide uniqueness.
This commit is contained in:
jaymode 2015-05-22 08:01:24 -04:00
parent d33f0e2527
commit fd7d6caba7
1 changed files with 5 additions and 2 deletions

View File

@ -422,8 +422,11 @@ public class PluginsService extends AbstractComponent {
// Trying JVM plugins: looking for es-plugin.properties files
try {
Enumeration<URL> pluginUrls = settings.getClassLoader().getResources(esPluginPropertiesFile);
while (pluginUrls.hasMoreElements()) {
URL pluginUrl = pluginUrls.nextElement();
// use a set for uniqueness as some classloaders such as groovy's can return the same URL multiple times and
// these plugins should only be loaded once
HashSet<URL> uniqueUrls = new HashSet<>(Collections.list(pluginUrls));
for (URL pluginUrl : uniqueUrls) {
Properties pluginProps = new Properties();
InputStream is = null;
try {