External Gadgets not working due to error with MacroMetadataProvider

Summary

External gadgets won't be found in the Macro Browser due to errors from the MacroMetadataProvider. You also won't be able to insert them manually, as the summary of the macro won't appear as the following screenshots:

Working gadget:

Not working:

Environment

• Confluence 6.2.0(with and without proxy)

Steps to Reproduce

1. Setup Confluence and JIRA with SSL(selfsigned certificate).
2. Add a gadget feed in Confluence.
3. Stop both services and revert the changes(remove the SSL).
4. Remove the existing gadget feed(with HTTTPS url).
5. Add a new gadget feed(with HTTP url)
   or

1. Install Copy Page Tree add-on( v2.5.0, v2.5.2 or v2.5.3)

Expected Results

External Gadgets will be found in the macro browser and you will be able to insert them.

Actual Results

Macros are not found and manually inserting the gadget doesn't work. Logs will show:

2017-06-06 17:10:15,693 ERROR [http-nio-8090-exec-4] [confluence.macro.browser.DefaultMacroMetadataManager] buildMacroSummaries Error getting summaries from MacroMetadataProvider,
– referer: [http://localhost:8090/confluence/display/BLAN/teste+2] | url: /confluence/plugins/macrobrowser/browse-macros.action | traceId: 5185927b4b60903a | userName: admin | action: browse-macros
java.lang.NullPointerException
at com.atlassian.confluence.cache.ehcache.EhCacheManager.wrapCache(EhCacheManager.java:151)
at com.atlassian.confluence.cache.ehcache.EhCacheManager.getCache(EhCacheManager.java:160)
at com.atlassian.confluence.cache.ehcache.EhCacheManager.getCaches(EhCacheManager.java:141)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)

Notes

• Flushing the cache won't fix.
• Clear the plugins cache won't fix.
• Restart both instances won't fix.
• No errors besides the above one in the logs.

Workaround

In case you have the Copy Page Tree add-on installed( v2.5.0, v2.5.2 or v2.5.3), uninstall it or downgrade it.