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//
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using System;
using System.Collections.Concurrent;
using System.Collections.Generic;
using System.ComponentModel.Composition;
using System.Diagnostics;
using System.Diagnostics.Contracts;
using System.IO;
using System.Linq;
using System.Net;
using System.Threading;
using System.Threading.Tasks;
using System.Threading.Tasks.Dataflow;
using Castle.ActiveRecord;
using Pithos.Interfaces;
using Pithos.Network;
using log4net;
namespace Pithos.Core.Agents
{
//TODO: Ensure all network operations use exact casing. Pithos is case sensitive
[Export]
public class NetworkAgent
{
private Agent _agent;
//A separate agent is used to execute delete actions immediatelly;
private ActionBlock _deleteAgent;
readonly ConcurrentDictionary _deletedFiles=new ConcurrentDictionary();
private readonly ManualResetEventSlim _pauseAgent = new ManualResetEventSlim(true);
[System.ComponentModel.Composition.Import]
public IStatusKeeper StatusKeeper { get; set; }
public IStatusNotification StatusNotification { get; set; }
private static readonly ILog Log = LogManager.GetLogger("NetworkAgent");
private readonly ConcurrentBag _accounts = new ConcurrentBag();
[System.ComponentModel.Composition.Import]
public IPithosSettings Settings { get; set; }
private bool _firstPoll = true;
private TaskCompletionSource _tcs;
private ConcurrentDictionary _lastSeen=new ConcurrentDictionary();
public void Start()
{
_firstPoll = true;
_agent = Agent.Start(inbox =>
{
Action loop = null;
loop = () =>
{
_pauseAgent.Wait();
var message = inbox.Receive();
var process=message.Then(Process,inbox.CancellationToken);
inbox.LoopAsync(process, loop);
};
loop();
});
_deleteAgent = new ActionBlock(message =>ProcessDelete(message),new ExecutionDataflowBlockOptions{MaxDegreeOfParallelism=4});
/*
Action loop = null;
loop = () =>
{
var message = inbox.Receive();
var process = message.Then(ProcessDelete,inbox.CancellationToken);
inbox.LoopAsync(process, loop);
};
loop();
*/
}
private async Task Process(CloudAction action)
{
if (action == null)
throw new ArgumentNullException("action");
if (action.AccountInfo==null)
throw new ArgumentException("The action.AccountInfo is empty","action");
Contract.EndContractBlock();
UpdateStatus(PithosStatus.Syncing);
var accountInfo = action.AccountInfo;
using (log4net.ThreadContext.Stacks["NETWORK"].Push("PROCESS"))
{
Log.InfoFormat("[ACTION] Start Processing {0}", action);
var cloudFile = action.CloudFile;
var downloadPath = action.GetDownloadPath();
try
{
if (action.Action == CloudActionType.DeleteCloud)
{
//Redirect deletes to the delete agent
_deleteAgent.Post((CloudDeleteAction)action);
}
if (IsDeletedFile(action))
{
//Clear the status of already deleted files to avoid reprocessing
if (action.LocalFile != null)
this.StatusKeeper.ClearFileStatus(action.LocalFile.FullName);
}
else
{
switch (action.Action)
{
case CloudActionType.UploadUnconditional:
//Abort if the file was deleted before we reached this point
await UploadCloudFile(action);
break;
case CloudActionType.DownloadUnconditional:
await DownloadCloudFile(accountInfo, cloudFile, downloadPath);
break;
case CloudActionType.RenameCloud:
var moveAction = (CloudMoveAction)action;
RenameCloudFile(accountInfo, moveAction);
break;
case CloudActionType.MustSynch:
if (!File.Exists(downloadPath) && !Directory.Exists(downloadPath))
{
await DownloadCloudFile(accountInfo, cloudFile, downloadPath);
}
else
{
await SyncFiles(accountInfo, action);
}
break;
}
}
Log.InfoFormat("[ACTION] End Processing {0}:{1}->{2}", action.Action, action.LocalFile,
action.CloudFile.Name);
}
catch (WebException exc)
{
Log.ErrorFormat("[WEB ERROR] {0} : {1} -> {2} due to exception\r\n{3}", action.Action, action.LocalFile, action.CloudFile, exc);
}
catch (OperationCanceledException)
{
throw;
}
catch (DirectoryNotFoundException)
{
Log.ErrorFormat("{0} : {1} -> {2} failed because the directory was not found.\n Rescheduling a delete",
action.Action, action.LocalFile, action.CloudFile);
//Post a delete action for the missing file
Post(new CloudDeleteAction(action));
}
catch (FileNotFoundException)
{
Log.ErrorFormat("{0} : {1} -> {2} failed because the file was not found.\n Rescheduling a delete",
action.Action, action.LocalFile, action.CloudFile);
//Post a delete action for the missing file
Post(new CloudDeleteAction(action));
}
catch (Exception exc)
{
Log.ErrorFormat("[REQUEUE] {0} : {1} -> {2} due to exception\r\n{3}",
action.Action, action.LocalFile, action.CloudFile, exc);
_agent.Post(action);
}
finally
{
UpdateStatus(PithosStatus.InSynch);
}
}
}
private void UpdateStatus(PithosStatus status)
{
StatusKeeper.SetPithosStatus(status);
StatusNotification.Notify(new Notification());
}
///
/// Processes cloud delete actions
///
/// The delete action to execute
///
///
/// When a file/folder is deleted locally, we must delete it ASAP from the server and block any download
/// operations that may be in progress.
///
/// A separate agent is used to process deletes because the main agent may be busy with a long operation.
///
///
private async Task ProcessDelete(CloudDeleteAction action)
{
if (action == null)
throw new ArgumentNullException("action");
if (action.AccountInfo==null)
throw new ArgumentException("The action.AccountInfo is empty","action");
Contract.EndContractBlock();
var accountInfo = action.AccountInfo;
using (log4net.ThreadContext.Stacks["NETWORK"].Push("PROCESS"))
{
Log.InfoFormat("[ACTION] Start Processing {0}", action);
var cloudFile = action.CloudFile;
try
{
//Acquire a lock on the deleted file to prevent uploading/downloading operations from the normal
//agent
using (var gate = NetworkGate.Acquire(action.LocalFile.FullName, NetworkOperation.Deleting))
{
//Add the file URL to the deleted files list
var key = GetFileKey(action.CloudFile);
_deletedFiles[key] = DateTime.Now;
_pauseAgent.Reset();
// and then delete the file from the server
DeleteCloudFile(accountInfo, cloudFile);
Log.InfoFormat("[ACTION] End Delete {0}:{1}->{2}", action.Action, action.LocalFile,
action.CloudFile.Name);
}
}
catch (WebException exc)
{
Log.ErrorFormat("[WEB ERROR] {0} : {1} -> {2} due to exception\r\n{3}", action.Action, action.LocalFile, action.CloudFile, exc);
}
catch (OperationCanceledException)
{
throw;
}
catch (DirectoryNotFoundException)
{
Log.ErrorFormat("{0} : {1} -> {2} failed because the directory was not found.\n Rescheduling a delete",
action.Action, action.LocalFile, action.CloudFile);
//Repost a delete action for the missing file
_deleteAgent.Post(action);
}
catch (FileNotFoundException)
{
Log.ErrorFormat("{0} : {1} -> {2} failed because the file was not found.\n Rescheduling a delete",
action.Action, action.LocalFile, action.CloudFile);
//Post a delete action for the missing file
_deleteAgent.Post(action);
}
catch (Exception exc)
{
Log.ErrorFormat("[REQUEUE] {0} : {1} -> {2} due to exception\r\n{3}",
action.Action, action.LocalFile, action.CloudFile, exc);
_deleteAgent.Post(action);
}
finally
{
//Set the event when all delete actions are processed
if (_deleteAgent.InputCount == 0)
_pauseAgent.Set();
}
}
}
private static string GetFileKey(ObjectInfo info)
{
var key = String.Format("{0}/{1}/{2}", info.Account, info.Container,info.Name);
return key;
}
private async Task SyncFiles(AccountInfo accountInfo,CloudAction action)
{
if (accountInfo == null)
throw new ArgumentNullException("accountInfo");
if (action==null)
throw new ArgumentNullException("action");
if (action.LocalFile==null)
throw new ArgumentException("The action's local file is not specified","action");
if (!Path.IsPathRooted(action.LocalFile.FullName))
throw new ArgumentException("The action's local file path must be absolute","action");
if (action.CloudFile== null)
throw new ArgumentException("The action's cloud file is not specified", "action");
Contract.EndContractBlock();
var localFile = action.LocalFile;
var cloudFile = action.CloudFile;
var downloadPath=action.LocalFile.GetProperCapitalization();
var cloudHash = cloudFile.Hash.ToLower();
var localHash = action.LocalHash.Value.ToLower();
var topHash = action.TopHash.Value.ToLower();
//Not enough to compare only the local hashes, also have to compare the tophashes
//If any of the hashes match, we are done
if ((cloudHash == localHash || cloudHash == topHash))
{
Log.InfoFormat("Skipping {0}, hashes match",downloadPath);
return;
}
//The hashes DON'T match. We need to sync
var lastLocalTime = localFile.LastWriteTime;
var lastUpTime = cloudFile.Last_Modified;
//If the local file is newer upload it
if (lastUpTime <= lastLocalTime)
{
//It probably means it was changed while the app was down
UploadCloudFile(action);
}
else
{
//It the cloud file has a later date, it was modified by another user or computer.
//We need to check the local file's status
var status = StatusKeeper.GetFileStatus(downloadPath);
switch (status)
{
case FileStatus.Unchanged:
//If the local file's status is Unchanged, we can go on and download the newer cloud file
await DownloadCloudFile(accountInfo,cloudFile,downloadPath);
break;
case FileStatus.Modified:
//If the local file is Modified, we may have a conflict. In this case we should mark the file as Conflict
//We can't ensure that a file modified online since the last time will appear as Modified, unless we
//index all files before we start listening.
case FileStatus.Created:
//If the local file is Created, it means that the local and cloud files aren't related,
// yet they have the same name.
//In both cases we must mark the file as in conflict
ReportConflict(downloadPath);
break;
default:
//Other cases should never occur. Mark them as Conflict as well but log a warning
ReportConflict(downloadPath);
Log.WarnFormat("Unexcepted status {0} for file {1}->{2}", status,
downloadPath, action.CloudFile.Name);
break;
}
}
}
private void ReportConflict(string downloadPath)
{
if (String.IsNullOrWhiteSpace(downloadPath))
throw new ArgumentNullException("downloadPath");
Contract.EndContractBlock();
StatusKeeper.SetFileOverlayStatus(downloadPath, FileOverlayStatus.Conflict);
UpdateStatus(PithosStatus.HasConflicts);
var message = String.Format("Conflict detected for file {0}", downloadPath);
Log.Warn(message);
StatusNotification.NotifyChange(message, TraceLevel.Warning);
}
public void Post(CloudAction cloudAction)
{
if (cloudAction == null)
throw new ArgumentNullException("cloudAction");
if (cloudAction.AccountInfo==null)
throw new ArgumentException("The CloudAction.AccountInfo is empty","cloudAction");
Contract.EndContractBlock();
_pauseAgent.Wait();
//If the action targets a local file, add a treehash calculation
if (!(cloudAction is CloudDeleteAction) && cloudAction.LocalFile as FileInfo != null)
{
var accountInfo = cloudAction.AccountInfo;
var localFile = (FileInfo) cloudAction.LocalFile;
if (localFile.Length > accountInfo.BlockSize)
cloudAction.TopHash =
new Lazy(() => Signature.CalculateTreeHashAsync(localFile,
accountInfo.BlockSize,
accountInfo.BlockHash, Settings.HashingParallelism).Result
.TopHash.ToHashString());
else
{
cloudAction.TopHash = new Lazy(() => cloudAction.LocalHash.Value);
}
}
else
{
//The hash for a directory is the empty string
cloudAction.TopHash = new Lazy(() => String.Empty);
}
if (cloudAction is CloudDeleteAction)
_deleteAgent.Post((CloudDeleteAction)cloudAction);
else
_agent.Post(cloudAction);
}
/* class ObjectInfoByNameComparer:IEqualityComparer
{
public bool Equals(ObjectInfo x, ObjectInfo y)
{
return x.Name.Equals(y.Name,StringComparison.InvariantCultureIgnoreCase);
}
public int GetHashCode(ObjectInfo obj)
{
return obj.Name.ToLower().GetHashCode();
}
}*/
public void SynchNow()
{
if (_tcs!=null)
_tcs.TrySetResult(true);
else
{
//TODO: This may be OK for testing purposes, but we have no guarantee that it will
//work properly in production
PollRemoteFiles(repeat:false);
}
}
//Remote files are polled periodically. Any changes are processed
public async Task PollRemoteFiles(DateTime? since = null,bool repeat=true)
{
UpdateStatus(PithosStatus.Syncing);
StatusNotification.Notify(new PollNotification());
using (log4net.ThreadContext.Stacks["Retrieve Remote"].Push("All accounts"))
{
//If this poll fails, we will retry with the same since value
var nextSince = since;
try
{
//Next time we will check for all changes since the current check minus 1 second
//This is done to ensure there are no discrepancies due to clock differences
DateTime current = DateTime.Now.AddSeconds(-1);
var tasks = from accountInfo in _accounts
select ProcessAccountFiles(accountInfo, since);
await TaskEx.WhenAll(tasks.ToList());
_firstPoll = false;
//Reschedule the poll with the current timestamp as a "since" value
if (repeat)
nextSince = current;
else
return;
}
catch (Exception ex)
{
Log.ErrorFormat("Error while processing accounts\r\n{0}",ex);
//In case of failure retry with the same "since" value
}
UpdateStatus(PithosStatus.InSynch);
//Wait for the polling interval to pass or the Manual flat to be toggled
nextSince = await WaitForScheduledOrManualPoll(nextSince);
PollRemoteFiles(nextSince);
}
}
private async Task WaitForScheduledOrManualPoll(DateTime? since)
{
_tcs = new TaskCompletionSource();
var wait = TaskEx.Delay(TimeSpan.FromSeconds(Settings.PollingInterval), _agent.CancellationToken);
var signaledTask = await TaskEx.WhenAny(_tcs.Task, wait);
//If polling is signalled by SynchNow, ignore the since tag
if (signaledTask is Task)
return null;
return since;
}
public async Task ProcessAccountFiles(AccountInfo accountInfo,DateTime? since=null)
{
if (accountInfo==null)
throw new ArgumentNullException("accountInfo");
if (String.IsNullOrWhiteSpace(accountInfo.AccountPath))
throw new ArgumentException("The AccountInfo.AccountPath is empty","accountInfo");
Contract.EndContractBlock();
using (log4net.ThreadContext.Stacks["Retrieve Remote"].Push(accountInfo.UserName))
{
_pauseAgent.Wait();
Log.Info("Scheduled");
var client = new CloudFilesClient(accountInfo)
{
Proxy = PithosMonitor.ProxyFromSettings(this.Settings)
};
var containers = client.ListContainers(accountInfo.UserName);
CreateContainerFolders(accountInfo, containers);
try
{
_pauseAgent.Wait();
//Get the poll time now. We may miss some deletions but it's better to keep a file that was deleted
//than delete a file that was created while we were executing the poll
var pollTime = DateTime.Now;
//Get the list of server objects changed since the last check
//The name of the container is passed as state in order to create a dictionary of tasks in a subsequent step
var listObjects = (from container in containers
select Task>.Factory.StartNew(_ =>
client.ListObjects(accountInfo.UserName,container.Name, since),container.Name)).ToList();
var listShared = Task>.Factory.StartNew(_ => client.ListSharedObjects(since), "shared");
listObjects.Add(listShared);
var listTasks = await Task.Factory.WhenAll(listObjects.ToArray());
using (log4net.ThreadContext.Stacks["SCHEDULE"].Push("Process Results"))
{
var dict = listTasks.ToDictionary(t => t.AsyncState);
//Get all non-trash objects. Remember, the container name is stored in AsyncState
var remoteObjects = from objectList in listTasks
where (string) objectList.AsyncState != "trash"
from obj in objectList.Result
select obj;
//TODO: Change the way deleted objects are detected.
//The list operation returns all existing objects so we could detect deleted remote objects
//by detecting objects that exist only locally. There are several cases where this is NOT the case:
//1. The first time the application runs, as there may be files that were added while
// the application was down.
//2. An object that is currently being uploaded will not appear in the remote list
// until the upload finishes.
// SOLUTION 1: Check the upload/download queue for the file
// SOLUTION 2: Check the SQLite states for the file's entry. If it is being uploaded,
// or its last modification was after the current poll, don't delete it. This way we don't
// delete objects whose upload finished too late to be included in the list.
//We need to detect and protect against such situations
//TODO: Does FileState have a LastModification field?
//TODO: How do we update the LastModification field? Do we need to add SQLite triggers?
// Do we need to use a proper SQLite schema?
// We can create a trigger with
// CREATE TRIGGER IF NOT EXISTS update_last_modified UPDATE ON FileState FOR EACH ROW
// BEGIN
// UPDATE FileState SET LastModification=datetime('now') WHERE Id=old.Id;
// END;
//
//NOTE: Some files may have been deleted remotely while the application was down.
// We DO have to delete those files. Checking the trash makes it easy to detect them,
// Otherwise, we can't be really sure whether we need to upload or delete
// the local-only files.
// SOLUTION 1: Ask the user when such a local-only file is detected during the first poll.
// SOLUTION 2: Mark conflict and ask the user as in #1
var trashObjects = dict["trash"].Result;
var sharedObjects = dict["shared"].Result;
//Items with the same name, hash may be both in the container and the trash
//Don't delete items that exist in the container
var realTrash = from trash in trashObjects
where
!remoteObjects.Any(
info => info.Name == trash.Name && info.Hash == trash.Hash)
select trash;
ProcessTrashedFiles(accountInfo, realTrash);
var cleanRemotes = (from info in remoteObjects.Union(sharedObjects)
let name = info.Name
where !name.EndsWith(".ignore", StringComparison.InvariantCultureIgnoreCase) &&
!name.StartsWith(FolderConstants.CacheFolder + "/",
StringComparison.InvariantCultureIgnoreCase)
select info).ToList();
var differencer = _differencer.PostSnapshot(accountInfo, cleanRemotes);
ProcessDeletedFiles(accountInfo, differencer.Deleted, pollTime);
//Create a list of actions from the remote files
var allActions = ChangesToActions(accountInfo, differencer.Changed)
.Union(
CreatesToActions(accountInfo,differencer.Created));
//var relativePath = objectInfo.RelativeUrlToFilePath(accountInfo.UserName);
//And remove those that are already being processed by the agent
var distinctActions = allActions
.Except(_agent.GetEnumerable(), new PithosMonitor.LocalFileComparer())
.ToList();
//Queue all the actions
foreach (var message in distinctActions)
{
Post(message);
}
Log.Info("[LISTENER] End Processing");
}
}
catch (Exception ex)
{
Log.ErrorFormat("[FAIL] ListObjects for{0} in ProcessRemoteFiles with {1}", accountInfo.UserName, ex);
return;
}
Log.Info("[LISTENER] Finished");
}
}
AccountsDifferencer _differencer= new AccountsDifferencer();
/*
Dictionary> _currentSnapshot = new Dictionary>();
Dictionary> _previousSnapshot = new Dictionary>();
*/
///
/// Deletes local files that are not found in the list of cloud files
///
///
///
///
private void ProcessDeletedFiles(AccountInfo accountInfo, IEnumerable cloudFiles, DateTime pollTime)
{
if (accountInfo == null)
throw new ArgumentNullException("accountInfo");
if (String.IsNullOrWhiteSpace(accountInfo.AccountPath))
throw new ArgumentException("The AccountInfo.AccountPath is empty", "accountInfo");
if (cloudFiles == null)
throw new ArgumentNullException("cloudFiles");
Contract.EndContractBlock();
//On the first run
if (_firstPoll)
{
//Only consider files that are not being modified, ie they are in the Unchanged state
var deleteCandidates = FileState.Queryable.Where(state =>
state.FilePath.StartsWith(accountInfo.AccountPath)
&& state.FileStatus == FileStatus.Unchanged).ToList();
//TODO: filesToDelete must take into account the Others container
var filesToDelete = (from deleteCandidate in deleteCandidates
let localFile = FileInfoExtensions.FromPath(deleteCandidate.FilePath)
let relativeFilePath = localFile.AsRelativeTo(accountInfo.AccountPath)
where
!cloudFiles.Any(r => r.RelativeUrlToFilePath(accountInfo.UserName) == relativeFilePath)
select localFile).ToList();
//Set the status of missing files to Conflict
foreach (var item in filesToDelete)
{
//Try to acquire a gate on the file, to take into account files that have been dequeued
//and are being processed
using (var gate = NetworkGate.Acquire(item.FullName, NetworkOperation.Deleting))
{
if (gate.Failed)
continue;
StatusKeeper.SetFileState(item.FullName, FileStatus.Conflict, FileOverlayStatus.Deleted);
}
}
UpdateStatus(PithosStatus.HasConflicts);
StatusNotification.NotifyConflicts(filesToDelete, String.Format("{0} local files are missing from Pithos, possibly because they were deleted",filesToDelete.Count));
StatusNotification.NotifyForFiles(filesToDelete, String.Format("{0} files were deleted", filesToDelete.Count), TraceLevel.Info);
}
else
{
var deletedFiles = new List();
foreach (var objectInfo in cloudFiles)
{
var relativePath = objectInfo.RelativeUrlToFilePath(accountInfo.UserName);
var item = GetFileAgent(accountInfo).GetFileSystemInfo(relativePath);
if (item.Exists)
{
//Try to acquire a gate on the file, to take into account files that have been dequeued
//and are being processed
//TODO: The gate is not enough. Perhaps we need to keep a journal of processed files and check against
//that as well.
/*
using (var gate = NetworkGate.Acquire(item.FullName, NetworkOperation.Deleting))
{
if (gate.Failed)
continue;
*/
if ((item.Attributes & FileAttributes.ReadOnly) == FileAttributes.ReadOnly)
{
item.Attributes = item.Attributes & ~FileAttributes.ReadOnly;
}
item.Delete();
DateTime lastDate;
_lastSeen.TryRemove(item.FullName, out lastDate);
deletedFiles.Add(item);
/*
}
*/
}
StatusKeeper.SetFileState(item.FullName, FileStatus.Deleted, FileOverlayStatus.Deleted);
}
StatusNotification.NotifyForFiles(deletedFiles, String.Format("{0} files were deleted", deletedFiles.Count), TraceLevel.Info);
}
}
private static void CreateContainerFolders(AccountInfo accountInfo, IEnumerable containers)
{
var containerPaths = from container in containers
let containerPath = Path.Combine(accountInfo.AccountPath, container.Name)
where container.Name != FolderConstants.TrashContainer && !Directory.Exists(containerPath)
select containerPath;
foreach (var path in containerPaths)
{
Directory.CreateDirectory(path);
}
}
//Creates an appropriate action for each server file
private IEnumerable ChangesToActions(AccountInfo accountInfo,IEnumerable changes)
{
if (changes==null)
throw new ArgumentNullException();
Contract.EndContractBlock();
var fileAgent = GetFileAgent(accountInfo);
//In order to avoid multiple iterations over the files, we iterate only once
//over the remote files
foreach (var objectInfo in changes)
{
var relativePath = objectInfo.RelativeUrlToFilePath(accountInfo.UserName);
//and remove any matching objects from the list, adding them to the commonObjects list
if (fileAgent.Exists(relativePath))
{
//If a directory object already exists, we don't need to perform any other action
var localFile = fileAgent.GetFileSystemInfo(relativePath);
if (objectInfo.Content_Type == @"application/directory" && localFile is DirectoryInfo)
continue;
using (new SessionScope(FlushAction.Never))
{
var state = StatusKeeper.GetStateByFilePath(localFile.FullName);
_lastSeen[localFile.FullName] = DateTime.Now;
//FileState.FindByFilePath(localFile.FullName);
//Common files should be checked on a per-case basis to detect differences, which is newer
yield return new CloudAction(accountInfo, CloudActionType.MustSynch,
localFile, objectInfo, state, accountInfo.BlockSize,
accountInfo.BlockHash);
}
}
else
{
//Remote files should be downloaded
yield return new CloudDownloadAction(accountInfo,objectInfo);
}
}
}
private IEnumerable CreatesToActions(AccountInfo accountInfo,IEnumerable creates)
{
if (creates==null)
throw new ArgumentNullException();
Contract.EndContractBlock();
var fileAgent = GetFileAgent(accountInfo);
//In order to avoid multiple iterations over the files, we iterate only once
//over the remote files
foreach (var objectInfo in creates)
{
var relativePath = objectInfo.RelativeUrlToFilePath(accountInfo.UserName);
//and remove any matching objects from the list, adding them to the commonObjects list
if (fileAgent.Exists(relativePath))
{
//If the object already exists, we probably have a conflict
//If a directory object already exists, we don't need to perform any other action
var localFile = fileAgent.GetFileSystemInfo(relativePath);
StatusKeeper.SetFileState(localFile.FullName,FileStatus.Conflict,FileOverlayStatus.Conflict);
}
else
{
//Remote files should be downloaded
yield return new CloudDownloadAction(accountInfo,objectInfo);
}
}
}
//Creates an appropriate action for each server file
/*
private IEnumerable ObjectsToActions(AccountInfo accountInfo,IEnumerable remote)
{
if (remote==null)
throw new ArgumentNullException();
Contract.EndContractBlock();
var fileAgent = GetFileAgent(accountInfo);
//In order to avoid multiple iterations over the files, we iterate only once
//over the remote files
foreach (var objectInfo in remote)
{
var relativePath = objectInfo.RelativeUrlToFilePath(accountInfo.UserName);
//and remove any matching objects from the list, adding them to the commonObjects list
if (fileAgent.Exists(relativePath))
{
//If a directory object already exists, we don't need to perform any other action
var localFile = fileAgent.GetFileSystemInfo(relativePath);
if (objectInfo.Content_Type == @"application/directory" && localFile is DirectoryInfo)
continue;
using (new SessionScope(FlushAction.Never))
{
var state = StatusKeeper.GetStateByFilePath(localFile.FullName);
_lastSeen[localFile.FullName] = DateTime.Now;
//FileState.FindByFilePath(localFile.FullName);
//Common files should be checked on a per-case basis to detect differences, which is newer
yield return new CloudAction(accountInfo, CloudActionType.MustSynch,
localFile, objectInfo, state, accountInfo.BlockSize,
accountInfo.BlockHash);
}
}
else
{
//If there is no match we add them to the localFiles list
//but only if the file is not marked for deletion
var targetFile = Path.Combine(accountInfo.AccountPath, relativePath);
var fileStatus = StatusKeeper.GetFileStatus(targetFile);
if (fileStatus != FileStatus.Deleted)
{
//Remote files should be downloaded
yield return new CloudDownloadAction(accountInfo,objectInfo);
}
}
}
}
*/
private static FileAgent GetFileAgent(AccountInfo accountInfo)
{
return AgentLocator.Get(accountInfo.AccountPath);
}
private void ProcessTrashedFiles(AccountInfo accountInfo,IEnumerable trashObjects)
{
var fileAgent = GetFileAgent(accountInfo);
foreach (var trashObject in trashObjects)
{
var barePath = trashObject.RelativeUrlToFilePath(accountInfo.UserName);
//HACK: Assume only the "pithos" container is used. Must find out what happens when
//deleting a file from a different container
var relativePath = Path.Combine("pithos", barePath);
fileAgent.Delete(relativePath);
}
}
private void RenameCloudFile(AccountInfo accountInfo,CloudMoveAction action)
{
if (accountInfo==null)
throw new ArgumentNullException("accountInfo");
if (action==null)
throw new ArgumentNullException("action");
if (action.CloudFile==null)
throw new ArgumentException("CloudFile","action");
if (action.LocalFile==null)
throw new ArgumentException("LocalFile","action");
if (action.OldLocalFile==null)
throw new ArgumentException("OldLocalFile","action");
if (action.OldCloudFile==null)
throw new ArgumentException("OldCloudFile","action");
Contract.EndContractBlock();
var newFilePath = action.LocalFile.FullName;
//How do we handle concurrent renames and deletes/uploads/downloads?
//* A conflicting upload means that a file was renamed before it had a chance to finish uploading
// This should never happen as the network agent executes only one action at a time
//* A conflicting download means that the file was modified on the cloud. While we can go on and complete
// the rename, there may be a problem if the file is downloaded in blocks, as subsequent block requests for the
// same name will fail.
// This should never happen as the network agent executes only one action at a time.
//* A conflicting delete can happen if the rename was followed by a delete action that didn't have the chance
// to remove the rename from the queue.
// We can probably ignore this case. It will result in an error which should be ignored
//The local file is already renamed
StatusKeeper.SetFileOverlayStatus(newFilePath, FileOverlayStatus.Modified);
var account = action.CloudFile.Account ?? accountInfo.UserName;
var container = action.CloudFile.Container;
var client = new CloudFilesClient(accountInfo);
//TODO: What code is returned when the source file doesn't exist?
client.MoveObject(account, container, action.OldCloudFile.Name, container, action.CloudFile.Name);
StatusKeeper.SetFileStatus(newFilePath, FileStatus.Unchanged);
StatusKeeper.SetFileOverlayStatus(newFilePath, FileOverlayStatus.Normal);
NativeMethods.RaiseChangeNotification(newFilePath);
}
private void DeleteCloudFile(AccountInfo accountInfo, ObjectInfo cloudFile)
{
if (accountInfo == null)
throw new ArgumentNullException("accountInfo");
if (cloudFile==null)
throw new ArgumentNullException("cloudFile");
if (String.IsNullOrWhiteSpace(cloudFile.Container))
throw new ArgumentException("Invalid container", "cloudFile");
Contract.EndContractBlock();
var fileAgent = GetFileAgent(accountInfo);
using ( log4net.ThreadContext.Stacks["DeleteCloudFile"].Push("Delete"))
{
var fileName= cloudFile.RelativeUrlToFilePath(accountInfo.UserName);
var info = fileAgent.GetFileSystemInfo(fileName);
var fullPath = info.FullName.ToLower();
StatusKeeper.SetFileOverlayStatus(fullPath, FileOverlayStatus.Modified);
var account = cloudFile.Account ?? accountInfo.UserName;
var container = cloudFile.Container ;//?? FolderConstants.PithosContainer;
var client = new CloudFilesClient(accountInfo);
client.DeleteObject(account, container, cloudFile.Name);
StatusKeeper.ClearFileStatus(fullPath);
}
}
//Download a file.
private async Task DownloadCloudFile(AccountInfo accountInfo, ObjectInfo cloudFile , string filePath)
{
if (accountInfo == null)
throw new ArgumentNullException("accountInfo");
if (cloudFile == null)
throw new ArgumentNullException("cloudFile");
if (String.IsNullOrWhiteSpace(cloudFile.Account))
throw new ArgumentNullException("cloudFile");
if (String.IsNullOrWhiteSpace(cloudFile.Container))
throw new ArgumentNullException("cloudFile");
if (String.IsNullOrWhiteSpace(filePath))
throw new ArgumentNullException("filePath");
if (!Path.IsPathRooted(filePath))
throw new ArgumentException("The filePath must be rooted", "filePath");
Contract.EndContractBlock();
var localPath = Interfaces.FileInfoExtensions.GetProperFilePathCapitalization(filePath);
var relativeUrl = new Uri(cloudFile.Name, UriKind.Relative);
var url = relativeUrl.ToString();
if (cloudFile.Name.EndsWith(".ignore", StringComparison.InvariantCultureIgnoreCase))
return;
//Are we already downloading or uploading the file?
using (var gate=NetworkGate.Acquire(localPath, NetworkOperation.Downloading))
{
if (gate.Failed)
return;
//The file's hashmap will be stored in the same location with the extension .hashmap
//var hashPath = Path.Combine(FileAgent.CachePath, relativePath + ".hashmap");
var client = new CloudFilesClient(accountInfo);
var account = cloudFile.Account;
var container = cloudFile.Container;
if (cloudFile.Content_Type == @"application/directory")
{
if (!Directory.Exists(localPath))
Directory.CreateDirectory(localPath);
}
else
{
//Retrieve the hashmap from the server
var serverHash = await client.GetHashMap(account, container, url);
//If it's a small file
if (serverHash.Hashes.Count == 1)
//Download it in one go
await
DownloadEntireFileAsync(accountInfo, client, cloudFile, relativeUrl, localPath, serverHash);
//Otherwise download it block by block
else
await DownloadWithBlocks(accountInfo, client, cloudFile, relativeUrl, localPath, serverHash);
if (cloudFile.AllowedTo == "read")
{
var attributes = File.GetAttributes(localPath);
File.SetAttributes(localPath, attributes | FileAttributes.ReadOnly);
}
}
//Now we can store the object's metadata without worrying about ghost status entries
StatusKeeper.StoreInfo(localPath, cloudFile);
}
}
//Download a small file with a single GET operation
private async Task DownloadEntireFileAsync(AccountInfo accountInfo, CloudFilesClient client, ObjectInfo cloudFile, Uri relativeUrl, string filePath,TreeHash serverHash)
{
if (client == null)
throw new ArgumentNullException("client");
if (cloudFile==null)
throw new ArgumentNullException("cloudFile");
if (relativeUrl == null)
throw new ArgumentNullException("relativeUrl");
if (String.IsNullOrWhiteSpace(filePath))
throw new ArgumentNullException("filePath");
if (!Path.IsPathRooted(filePath))
throw new ArgumentException("The localPath must be rooted", "filePath");
Contract.EndContractBlock();
var localPath = Pithos.Interfaces.FileInfoExtensions.GetProperFilePathCapitalization(filePath);
//If the file already exists
if (File.Exists(localPath))
{
//First check with MD5 as this is a small file
var localMD5 = Signature.CalculateMD5(localPath);
var cloudHash=serverHash.TopHash.ToHashString();
if (localMD5==cloudHash)
return;
//Then check with a treehash
var localTreeHash = Signature.CalculateTreeHash(localPath, serverHash.BlockSize, serverHash.BlockHash);
var localHash = localTreeHash.TopHash.ToHashString();
if (localHash==cloudHash)
return;
}
StatusNotification.Notify(new CloudNotification { Data = cloudFile });
var fileAgent = GetFileAgent(accountInfo);
//Calculate the relative file path for the new file
var relativePath = relativeUrl.RelativeUriToFilePath();
//The file will be stored in a temporary location while downloading with an extension .download
var tempPath = Path.Combine(fileAgent.CachePath, relativePath + ".download");
//Make sure the target folder exists. DownloadFileTask will not create the folder
var tempFolder = Path.GetDirectoryName(tempPath);
if (!Directory.Exists(tempFolder))
Directory.CreateDirectory(tempFolder);
//Download the object to the temporary location
await client.GetObject(cloudFile.Account, cloudFile.Container, relativeUrl.ToString(), tempPath);
//Create the local folder if it doesn't exist (necessary for shared objects)
var localFolder = Path.GetDirectoryName(localPath);
if (!Directory.Exists(localFolder))
Directory.CreateDirectory(localFolder);
//And move it to its actual location once downloading is finished
if (File.Exists(localPath))
File.Replace(tempPath,localPath,null,true);
else
File.Move(tempPath,localPath);
//Notify listeners that a local file has changed
StatusNotification.NotifyChangedFile(localPath);
}
//Download a file asynchronously using blocks
public async Task DownloadWithBlocks(AccountInfo accountInfo, CloudFilesClient client, ObjectInfo cloudFile, Uri relativeUrl, string filePath, TreeHash serverHash)
{
if (client == null)
throw new ArgumentNullException("client");
if (cloudFile == null)
throw new ArgumentNullException("cloudFile");
if (relativeUrl == null)
throw new ArgumentNullException("relativeUrl");
if (String.IsNullOrWhiteSpace(filePath))
throw new ArgumentNullException("filePath");
if (!Path.IsPathRooted(filePath))
throw new ArgumentException("The filePath must be rooted", "filePath");
if (serverHash == null)
throw new ArgumentNullException("serverHash");
Contract.EndContractBlock();
var fileAgent = GetFileAgent(accountInfo);
var localPath = Interfaces.FileInfoExtensions.GetProperFilePathCapitalization(filePath);
//Calculate the relative file path for the new file
var relativePath = relativeUrl.RelativeUriToFilePath();
var blockUpdater = new BlockUpdater(fileAgent.CachePath, localPath, relativePath, serverHash);
//Calculate the file's treehash
var treeHash = await Signature.CalculateTreeHashAsync(localPath, serverHash.BlockSize, serverHash.BlockHash, 2);
//And compare it with the server's hash
var upHashes = serverHash.GetHashesAsStrings();
var localHashes = treeHash.HashDictionary;
for (int i = 0; i < upHashes.Length; i++)
{
//For every non-matching hash
var upHash = upHashes[i];
if (!localHashes.ContainsKey(upHash))
{
StatusNotification.Notify(new CloudNotification { Data = cloudFile });
if (blockUpdater.UseOrphan(i, upHash))
{
Log.InfoFormat("[BLOCK GET] ORPHAN FOUND for {0} of {1} for {2}", i, upHashes.Length, localPath);
continue;
}
Log.InfoFormat("[BLOCK GET] START {0} of {1} for {2}", i, upHashes.Length, localPath);
var start = i*serverHash.BlockSize;
//To download the last block just pass a null for the end of the range
long? end = null;
if (i < upHashes.Length - 1 )
end= ((i + 1)*serverHash.BlockSize) ;
//Download the missing block
var block = await client.GetBlock(cloudFile.Account, cloudFile.Container, relativeUrl, start, end);
//and store it
blockUpdater.StoreBlock(i, block);
Log.InfoFormat("[BLOCK GET] FINISH {0} of {1} for {2}", i, upHashes.Length, localPath);
}
}
//Want to avoid notifications if no changes were made
var hasChanges = blockUpdater.HasBlocks;
blockUpdater.Commit();
if (hasChanges)
//Notify listeners that a local file has changed
StatusNotification.NotifyChangedFile(localPath);
Log.InfoFormat("[BLOCK GET] COMPLETE {0}", localPath);
}
private async Task UploadCloudFile(CloudAction action)
{
if (action == null)
throw new ArgumentNullException("action");
Contract.EndContractBlock();
try
{
var accountInfo = action.AccountInfo;
var fileInfo = action.LocalFile;
if (fileInfo.Extension.Equals("ignore", StringComparison.InvariantCultureIgnoreCase))
return;
var relativePath = fileInfo.AsRelativeTo(accountInfo.AccountPath);
if (relativePath.StartsWith(FolderConstants.OthersFolder))
{
var parts = relativePath.Split('\\');
var accountName = parts[1];
var oldName = accountInfo.UserName;
var absoluteUri = accountInfo.StorageUri.AbsoluteUri;
var nameIndex = absoluteUri.IndexOf(oldName);
var root = absoluteUri.Substring(0, nameIndex);
accountInfo = new AccountInfo
{
UserName = accountName,
AccountPath = Path.Combine(accountInfo.AccountPath, parts[0], parts[1]),
StorageUri = new Uri(root + accountName),
BlockHash = accountInfo.BlockHash,
BlockSize = accountInfo.BlockSize,
Token = accountInfo.Token
};
}
var fullFileName = fileInfo.GetProperCapitalization();
using (var gate = NetworkGate.Acquire(fullFileName, NetworkOperation.Uploading))
{
//Abort if the file is already being uploaded or downloaded
if (gate.Failed)
return;
var cloudFile = action.CloudFile;
var account = cloudFile.Account ?? accountInfo.UserName;
var client = new CloudFilesClient(accountInfo);
//Even if GetObjectInfo times out, we can proceed with the upload
var info = client.GetObjectInfo(account, cloudFile.Container, cloudFile.Name);
//If this is a read-only file, do not upload changes
if (info.AllowedTo == "read")
return;
//TODO: Check how a directory hash is calculated -> All dirs seem to have the same hash
if (fileInfo is DirectoryInfo)
{
//If the directory doesn't exist the Hash property will be empty
if (String.IsNullOrWhiteSpace(info.Hash))
//Go on and create the directory
await client.PutObject(account, cloudFile.Container, cloudFile.Name, fullFileName, String.Empty, "application/directory");
}
else
{
var cloudHash = info.Hash.ToLower();
var hash = action.LocalHash.Value;
var topHash = action.TopHash.Value;
//If the file hashes match, abort the upload
if (hash == cloudHash || topHash == cloudHash)
{
//but store any metadata changes
StatusKeeper.StoreInfo(fullFileName, info);
Log.InfoFormat("Skip upload of {0}, hashes match", fullFileName);
return;
}
//Mark the file as modified while we upload it
StatusKeeper.SetFileOverlayStatus(fullFileName, FileOverlayStatus.Modified);
//And then upload it
//Upload even small files using the Hashmap. The server may already contain
//the relevant block
//First, calculate the tree hash
var treeHash = await Signature.CalculateTreeHashAsync(fullFileName, accountInfo.BlockSize,
accountInfo.BlockHash, 2);
await UploadWithHashMap(accountInfo, cloudFile, fileInfo as FileInfo, cloudFile.Name, treeHash);
}
//If everything succeeds, change the file and overlay status to normal
StatusKeeper.SetFileState(fullFileName, FileStatus.Unchanged, FileOverlayStatus.Normal);
}
//Notify the Shell to update the overlays
NativeMethods.RaiseChangeNotification(fullFileName);
StatusNotification.NotifyChangedFile(fullFileName);
}
catch (AggregateException ex)
{
var exc = ex.InnerException as WebException;
if (exc == null)
throw ex.InnerException;
if (HandleUploadWebException(action, exc))
return;
throw;
}
catch (WebException ex)
{
if (HandleUploadWebException(action, ex))
return;
throw;
}
catch (Exception ex)
{
Log.Error("Unexpected error while uploading file", ex);
throw;
}
}
//Returns true if an action concerns a file that was deleted
private bool IsDeletedFile(CloudAction action)
{
//Doesn't work for actions targeting shared files
if (action.IsShared)
return false;
var key = GetFileKey(action.CloudFile);
DateTime entryDate;
if (_deletedFiles.TryGetValue(key, out entryDate))
{
//If the delete entry was created after this action, abort the action
if (entryDate > action.Created)
return true;
//Otherwise, remove the stale entry
_deletedFiles.TryRemove(key, out entryDate);
}
return false;
}
private bool HandleUploadWebException(CloudAction action, WebException exc)
{
var response = exc.Response as HttpWebResponse;
if (response == null)
throw exc;
if (response.StatusCode == HttpStatusCode.Unauthorized)
{
Log.Error("Not allowed to upload file", exc);
var message = String.Format("Not allowed to uplad file {0}", action.LocalFile.FullName);
StatusKeeper.SetFileState(action.LocalFile.FullName, FileStatus.Unchanged, FileOverlayStatus.Normal);
StatusNotification.NotifyChange(message, TraceLevel.Warning);
return true;
}
return false;
}
public async Task UploadWithHashMap(AccountInfo accountInfo,ObjectInfo cloudFile,FileInfo fileInfo,string url,TreeHash treeHash)
{
if (accountInfo == null)
throw new ArgumentNullException("accountInfo");
if (cloudFile==null)
throw new ArgumentNullException("cloudFile");
if (fileInfo == null)
throw new ArgumentNullException("fileInfo");
if (String.IsNullOrWhiteSpace(url))
throw new ArgumentNullException(url);
if (treeHash==null)
throw new ArgumentNullException("treeHash");
if (String.IsNullOrWhiteSpace(cloudFile.Container) )
throw new ArgumentException("Invalid container","cloudFile");
Contract.EndContractBlock();
var fullFileName = fileInfo.GetProperCapitalization();
var account = cloudFile.Account ?? accountInfo.UserName;
var container = cloudFile.Container ;
var client = new CloudFilesClient(accountInfo);
//Send the hashmap to the server
var missingHashes = await client.PutHashMap(account, container, url, treeHash);
//If the server returns no missing hashes, we are done
while (missingHashes.Count > 0)
{
var buffer = new byte[accountInfo.BlockSize];
foreach (var missingHash in missingHashes)
{
//Find the proper block
var blockIndex = treeHash.HashDictionary[missingHash];
var offset = blockIndex*accountInfo.BlockSize;
var read = fileInfo.Read(buffer, offset, accountInfo.BlockSize);
try
{
//And upload the block
await client.PostBlock(account, container, buffer, 0, read);
Log.InfoFormat("[BLOCK] Block {0} of {1} uploaded", blockIndex, fullFileName);
}
catch (Exception exc)
{
Log.ErrorFormat("[ERROR] uploading block {0} of {1}\n{2}", blockIndex, fullFileName, exc);
}
}
//Repeat until there are no more missing hashes
missingHashes = await client.PutHashMap(account, container, url, treeHash);
}
}
public void AddAccount(AccountInfo accountInfo)
{
if (!_accounts.Contains(accountInfo))
_accounts.Add(accountInfo);
}
}
}