//
// Summary:
// Update the `LastWrittenAt`,`LastSize`,`LastStatus`,`LastUpdatedAt`,`LastChecksum`
// properties of each file in `files` according to the actual state of the file in the filesystem.
//
// NOTE: This function has a side effect - It updates properties of items from `files`.
//
private void DoUpdateBackupPlanFilesStatus(LinkedList <Models.BackupPlanFile> files, bool isNewVersion)
{
Assert.IsNotNull(files);
ISession session = NHibernateHelper.GetSession();
BackupedFileRepository daoBackupedFile = new BackupedFileRepository(session);
BlockPerfStats stats = new BlockPerfStats();
stats.Begin();
// Check all files.
LinkedListNode <Models.BackupPlanFile> node = files.First;
while (node != null)
{
var next = node.Next;
Models.BackupPlanFile entry = node.Value;
// TODO(jweyrich): Measure whether `daoBackupedFile.GetLatestVersion(entry)` is faster or not,
// and whether "entry.Versions.anything" would cause all related version to be fetched.
#if false
Models.BackupedFile lastVersion = entry.Versions != null && entry.Versions.Count > 0
? entry.Versions.Last() : null;
#else
// This may be a version that has not COMPLETED the transfer.
Models.BackupedFile lastVersion = entry.Id.HasValue ? daoBackupedFile.GetLatestVersion(entry) : null;
#endif
// Throw if the operation was canceled.
CancellationToken.ThrowIfCancellationRequested();
//
// Check what happened to the file.
//
bool fileExistsOnFilesystem = FileManager.FileExists(entry.Path);
Models.BackupFileStatus?changeStatusTo = null;
try
{
//
// Update file properties
//
if (fileExistsOnFilesystem)
{
try
{
DateTime fileLastWrittenAt = FileManager.UnsafeGetFileLastWriteTimeUtc(entry.Path);
long fileLength = FileManager.UnsafeGetFileSize(entry.Path);
entry.LastWrittenAt = fileLastWrittenAt;
entry.LastSize = fileLength;
}
catch (Exception ex)
{
string message = string.Format("Caught an exception while retrieving file properties: {0}", ex.Message);
Results.OnFileFailed(this, new FileVersionerEventArgs {
FilePath = entry.Path, FileSize = 0
}, message);
logger.Warn(message);
throw;
}
try
{
// Skip files larger than `MAX_FILESIZE_TO_HASH`.
int result = BigInteger.Compare(entry.LastSize, MAX_FILESIZE_TO_HASH);
if (result < 0)
{
entry.LastChecksum = CalculateHashForFile(entry.Path);
}
}
catch (Exception ex)
{
string message = string.Format("Caught an exception while calculating the file hash: {0}", ex.Message);
Results.OnFileFailed(this, new FileVersionerEventArgs {
FilePath = entry.Path, FileSize = 0
}, message);
logger.Warn(message);
throw;
}
Results.OnFileCompleted(this, new FileVersionerEventArgs {
FilePath = entry.Path, FileSize = entry.LastSize
});
}
//
// Update file status
//
if (lastVersion != null) // File was backed up at least once in the past?
{
switch (entry.LastStatus)
{
case Models.BackupFileStatus.DELETED: // File was marked as DELETED by a previous backup?
if (fileExistsOnFilesystem) // Exists?
{
changeStatusTo = Models.BackupFileStatus.ADDED;
}
break;
case Models.BackupFileStatus.REMOVED: // File was marked as REMOVED by a previous backup?
if (fileExistsOnFilesystem) // Exists?
{
changeStatusTo = Models.BackupFileStatus.ADDED;
}
else
{
// QUESTION: Do we really care to transition REMOVED to DELETED?
changeStatusTo = Models.BackupFileStatus.DELETED;
}
break;
default: // ADDED, MODIFIED, UNCHANGED
if (fileExistsOnFilesystem) // Exists?
{
// DO NOT verify whether the file changed for a `ResumeBackupOperation`,
// only for `NewBackupOperation`.
if (isNewVersion)
{
if (IsFileModified(entry, lastVersion)) // Modified?
{
changeStatusTo = Models.BackupFileStatus.MODIFIED;
}
else if (NeedsToRetryFile(entry, lastVersion)) // Didn't complete last file transfer?
{
changeStatusTo = Models.BackupFileStatus.MODIFIED;
}
else // Not modified?
{
changeStatusTo = Models.BackupFileStatus.UNCHANGED;
}
}
}
else // Deleted from filesystem?
{
changeStatusTo = Models.BackupFileStatus.DELETED;
}
break;
}
}
else // Adding to this backup?
{
if (fileExistsOnFilesystem) // Exists?
{
changeStatusTo = Models.BackupFileStatus.ADDED;
}
else
{
// Error? Can't add a non-existent file to the plan.
}
}
if (changeStatusTo.HasValue)
{
entry.LastStatus = changeStatusTo.Value;
entry.UpdatedAt = DateTime.UtcNow;
}
}
catch (Exception ex)
{
FailedFile <Models.BackupPlanFile> failedEntry = new FailedFile <Models.BackupPlanFile>(entry, ex.Message, ex);
ChangeSet.FailedFiles.AddLast(failedEntry);
// Remove this entry from `files` as it clearly failed.
files.Remove(node); // Complexity is O(1)
}
node = next;
}
stats.End();
}