From a0e9179ff113b782fcce55649d1658b21bbb7791 Mon Sep 17 00:00:00 2001
From: Kory Draughn <korydraughn@ymail.com>
Date: Wed, 3 Feb 2021 08:43:42 -0500
Subject: [PATCH] squash. only hard links the latest good replica.

---
 .../nfsrods/vfs/IRODSVirtualFileSystem.java   | 58 ++++++++++++++++---
 1 file changed, 49 insertions(+), 9 deletions(-)

diff --git a/irods-vfs-impl/src/main/java/org/irods/nfsrods/vfs/IRODSVirtualFileSystem.java b/irods-vfs-impl/src/main/java/org/irods/nfsrods/vfs/IRODSVirtualFileSystem.java
index 0ed047d7..e147cfc7 100644
--- a/irods-vfs-impl/src/main/java/org/irods/nfsrods/vfs/IRODSVirtualFileSystem.java
+++ b/irods-vfs-impl/src/main/java/org/irods/nfsrods/vfs/IRODSVirtualFileSystem.java
@@ -77,6 +77,7 @@
 import org.irods.jargon.core.pub.DataObjectAO;
 import org.irods.jargon.core.pub.IRODSAccessObjectFactory;
 import org.irods.jargon.core.pub.IRODSFileSystemAO;
+import org.irods.jargon.core.pub.IRODSGenQueryExecutor;
 import org.irods.jargon.core.pub.RuleProcessingAO;
 import org.irods.jargon.core.pub.UserAO;
 import org.irods.jargon.core.pub.UserGroupAO;
@@ -88,8 +89,13 @@
 import org.irods.jargon.core.pub.io.IRODSFile;
 import org.irods.jargon.core.pub.io.IRODSFileFactory;
 import org.irods.jargon.core.pub.io.IRODSRandomAccessFile;
+import org.irods.jargon.core.query.AbstractIRODSGenQuery.RowCountOptions;
 import org.irods.jargon.core.query.CollectionAndDataObjectListingEntry;
 import org.irods.jargon.core.query.CollectionAndDataObjectListingEntry.ObjectType;
+import org.irods.jargon.core.query.IRODSGenQuery;
+import org.irods.jargon.core.query.IRODSQueryResultRow;
+import org.irods.jargon.core.query.IRODSQueryResultSet;
+import org.irods.jargon.core.query.JargonQueryException;
 import org.irods.jargon.core.rule.IRODSRuleExecResult;
 import org.irods.jargon.core.rule.IrodsRuleInvocationTypeEnum;
 import org.irods.jargon.core.rule.RuleInvocationConfiguration;
@@ -651,7 +657,7 @@ public Access checkAcl(Subject _subject, Inode _inode, int _accessMask) throws C
         }
 
         String path = getPath(toInodeNumber(_inode)).toString();
-        
+
         // Key   (String) => <user_id>#<access_mask>#<path>
         // Value (Access) => ALLOW/DENY
         // Cached stat information must be scoped to the user due to the permissions
@@ -852,15 +858,22 @@ public Inode link(Inode _parent, Inode _existing, String _target, Subject _subje
         
         // _parent + _target => the absolute path of the hard link.
         
-        Map<String, String> jsonInput = new HashMap<>();
-        jsonInput.put("operation", "hard_link_create");
-        jsonInput.put("logical_path", linkTargetPath.toString());
-        jsonInput.put("replica_number", "0");
-        jsonInput.put("link_name", linkNamePath.toString());
-        
         try
         {
             IRODSAccount acct = getCurrentIRODSUser().getAccount();
+            Optional<String> replicaNumber = getReplicaNumberOfLatestGoodReplica(acct, linkTargetPath);
+            
+            if (!replicaNumber.isPresent())
+            {
+                throw new NoEntException(String.format("No good replica to link for [%s]", linkTargetPath));
+            }
+
+            Map<String, String> jsonInput = new HashMap<>();
+            jsonInput.put("operation", "hard_link_create");
+            jsonInput.put("logical_path", linkTargetPath.toString());
+            jsonInput.put("replica_number", replicaNumber.get());
+            jsonInput.put("link_name", linkNamePath.toString());
+        
             RuleProcessingAO rpao = factory_.getRuleProcessingAO(acct);
             RuleInvocationConfiguration ctx = new RuleInvocationConfiguration();
             ctx.setIrodsRuleInvocationTypeEnum(IrodsRuleInvocationTypeEnum.OTHER);
@@ -881,7 +894,7 @@ public Inode link(Inode _parent, Inode _existing, String _target, Subject _subje
 
             return toFh(newInodeNumber);
         }
-        catch (JargonException e)
+        catch (JargonException | JargonQueryException e)
         {
             log_.error(e.getMessage());
             throw new IOException(e);
@@ -1357,7 +1370,7 @@ private Stat statPath(Path _path, long _inodeNumber) throws IOException
 
             stat.setUid(userId);
             stat.setGid(groupId);
-            stat.setNlink(1);
+            stat.setNlink(1); // TODO: Should hard links affect this number?
             stat.setDev(17);
             stat.setIno((int) _inodeNumber);
             stat.setRdev(0);
@@ -1611,6 +1624,33 @@ private boolean isAdministrator(String _userName) throws JargonException
 
         return user.getUserType() == UserTypeEnum.RODS_ADMIN;
     }
+    
+    private Optional<String> getReplicaNumberOfLatestGoodReplica(IRODSAccount _acct, Path _logicalPath)
+        throws JargonException, JargonQueryException
+    {
+        // @formatter:off
+        String gql = String.format("select max(DATA_MODIFY_TIME) " +
+                                   "where " +
+                                   " COLL_NAME = '%s' and" +
+                                   " DATA_NAME = '%s' and" +
+                                   " DATA_REPL_STATUS = '1'",
+                                   _logicalPath.getParent(),
+                                   _logicalPath.getFileName());
+        // @formatter:on
+        final int rowsDesired = 1;
+        IRODSGenQuery genQuery = IRODSGenQuery.instance(gql, rowsDesired, RowCountOptions.ROW_COUNT_FOR_THIS_RESULT);
+        IRODSGenQueryExecutor executor = factory_.getIRODSGenQueryExecutor(_acct);
+
+        final int partialStartIndex = 0;
+        IRODSQueryResultSet resultSet = executor.executeIRODSQueryAndCloseResult(genQuery, partialStartIndex);
+
+        for (IRODSQueryResultRow row : resultSet.getResults())
+        {
+            return Optional.of(row.getColumn(0));
+        }
+
+        return Optional.empty();
+    }
 
     private void closeCurrentConnection() throws IOException
     {