[SOLR-12429] ZK upconfig throws confusing error when it encounters a symlink

• Type: Bug
• Status: Open
• Priority: Major
• Resolution: Unresolved
• Affects Version/s: 7.3.1
• Component/s: SolrCLI
• Assignee: Unassigned
• Reporter: Shawn Heisey
• Created: 30/May/18 18:09
• Updated: 08/Jun/19 15:12

Description

If a configset being uploaded to ZK contains a symlink pointing at a directory, an error is thrown, but it doesn't explain the real problem. The upconfig should detect symlinks and throw an error indicating that they aren't supported. If we can detect any other type of file that upconfig can't use (sockets, device files, etc), the error message should be relevant.

Exception in thread "main" java.io.IOException: File '/var/solr/mbsssss/artist/conf/common' exists but is a directory
	at org.apache.commons.io.FileUtils.openInputStream(FileUtils.java:286)
	at org.apache.commons.io.FileUtils.readFileToByteArray(FileUtils.java:1815)
	at org.apache.solr.common.cloud.SolrZkClient.makePath(SolrZkClient.java:391)
	at org.apache.solr.common.cloud.ZkMaintenanceUtils$1.visitFile(ZkMaintenanceUtils.java:305)
	at org.apache.solr.common.cloud.ZkMaintenanceUtils$1.visitFile(ZkMaintenanceUtils.java:291)
	at java.nio.file.Files.walkFileTree(Files.java:2670)
	at java.nio.file.Files.walkFileTree(Files.java:2742)
	at org.apache.solr.common.cloud.ZkMaintenanceUtils.uploadToZK(ZkMaintenanceUtils.java:291)
	at org.apache.solr.common.cloud.SolrZkClient.uploadToZK(SolrZkClient.java:793)
	at org.apache.solr.common.cloud.ZkConfigManager.uploadConfigDir(ZkConfigManager.java:78)
	at org.apache.solr.cloud.ZkCLI.main(ZkCLI.java:236)

I have not tested whether a symlink pointing at a file works, but I think that an error should be thrown for ANY symlink.