No need to add file if it already exists

2 files changed, 44 insertions, 6 deletions

diff --git a/configserver/src/main/java/com/yahoo/vespa/config/server/filedistribution/FileDirectory.java b/configserver/src/main/java/com/yahoo/vespa/config/server/filedistribution/FileDirectory.java
index 521f34b700f..5c8d693eeb7 100644
--- a/configserver/src/main/java/com/yahoo/vespa/config/server/filedistribution/FileDirectory.java
+++ b/configserver/src/main/java/com/yahoo/vespa/config/server/filedistribution/FileDirectory.java
@@ -98,17 +98,19 @@ public class FileDirectory  {
 
     public FileReference addFile(File source) throws IOException {
         Long hash = computeHash(source);
-        verifyExistingFile(source, hash);
         FileReference fileReference = fileReferenceFromHash(hash);
-        return addFile(source, fileReference);
+
+        if (shouldAddFile(source, hash))
+            return addFile(source, fileReference);
+
+        return fileReference;
     }
 
-    // If there exists a directory for a file reference, but content does not have correct hash or the file we want to add
-    // does not exist in the directory, delete the directory
-    private void verifyExistingFile(File source, Long hashOfFileToBeAdded) throws IOException {
+    // Check if we should add file, it might already exist
+    private boolean shouldAddFile(File source, Long hashOfFileToBeAdded) throws IOException {
         FileReference fileReference = fileReferenceFromHash(hashOfFileToBeAdded);
         File destinationDir = destinationDir(fileReference);
-        if (!destinationDir.exists()) return;
+        if ( ! destinationDir.exists()) return true;
 
         File existingFile = destinationDir.toPath().resolve(source.getName()).toFile();
         if ( ! existingFile.exists() || ! computeHash(existingFile).equals(hashOfFileToBeAdded)) {
@@ -116,7 +118,11 @@ public class FileDirectory  {
                     "' has content that does not match its hash, deleting everything in " +
                     destinationDir.getAbsolutePath());
             IOUtils.recursiveDeleteDir(destinationDir);
+            return true;
         }
+
+        log.log(Level.FINE, "Directory for file reference '" + fileReference.value() + "' already exists and has all content");
+        return false;
     }
 
     private File destinationDir(FileReference fileReference) {
diff --git a/configserver/src/test/java/com/yahoo/vespa/config/server/filedistribution/FileDirectoryTest.java b/configserver/src/test/java/com/yahoo/vespa/config/server/filedistribution/FileDirectoryTest.java
index dd13a8f5f58..e5ef893d135 100644
--- a/configserver/src/test/java/com/yahoo/vespa/config/server/filedistribution/FileDirectoryTest.java
+++ b/configserver/src/test/java/com/yahoo/vespa/config/server/filedistribution/FileDirectoryTest.java
@@ -106,6 +106,38 @@ public class FileDirectoryTest {
         assertEquals("bebc5a1aee74223d", fileReference.value());
     }
 
+    @Test
+    public void requireThatNothingIsDoneIfFileReferenceExists() throws IOException {
+        FileDirectory fileDirectory = new FileDirectory(temporaryFolder.getRoot());
+
+        String subdirName = "subdir";
+        File subDirectory = new File(temporaryFolder.getRoot(), subdirName);
+        createFileInSubDir(subDirectory, "foo", "some content");
+        FileReference fileReference = fileDirectory.addFile(subDirectory);
+        File dir = fileDirectory.getFile(fileReference);
+        assertTrue(dir.exists());
+        File foo = new File(dir, "foo");
+        assertTrue(foo.exists());
+        FileTime fooCreatedTimestamp = Files.readAttributes(foo.toPath(), BasicFileAttributes.class).creationTime();
+        assertFalse(new File(dir, "doesnotexist").exists());
+        assertEquals("bebc5a1aee74223d", fileReference.value());
+
+        try { Thread.sleep(1000);} catch (InterruptedException e) { /*ignore */ } // Needed since we have timestamp resolution of 1 second
+        // Add a file that already exists, nothing should happen
+        createFileInSubDir(subDirectory, "foo", "some content"); // same as before, nothing should happen
+        FileReference fileReference3 = fileDirectory.addFile(subDirectory);
+        dir = fileDirectory.getFile(fileReference3);
+        assertTrue(new File(dir, "foo").exists());
+        assertEquals("bebc5a1aee74223d", fileReference3.value()); // same hash
+
+        File foo2 = new File(dir, "foo");
+        assertTrue(dir.exists());
+        assertTrue(foo2.exists());
+        FileTime barCreatedTimestamp = Files.readAttributes(foo2.toPath(), BasicFileAttributes.class).creationTime();
+        // Check that creation timestamp is newer than the old one to be sure that a new file was written
+        assertEquals(barCreatedTimestamp, fooCreatedTimestamp);
+    }
+
     // Content in created file is equal to the filename string
     private FileReference createFile(String filename) throws IOException {
         File file = temporaryFolder.newFile(filename);