private void _forkProvider_ForkChanged(object sender, ForkChangedEventArgs e)
{
if (e.ForkIds.Contains(Fork.Id))
{
Fork = _forkProvider.GetFork(Fork.Id);
}
}
/// <summary>
/// Create new master fork with the data from an exsiting fork
/// This is used to prune unused forks
/// The data is trasferred to a new master fork to allow checking the data before deleting the old fork tree.
/// </summary>
/// <param name="forkId">Fork to prune</param>
/// <returns>New master fork id with the data from the old fork</returns>
public int PruneForks(int forkId)
{
var usedKeys = new HashSet <string>();
var deletedKeys = new HashSet <string>();
var valuesToSet = new List <Tuple <string, TDataTypesEnum, byte[], object> >();
var fork = ForkProvider.GetFork(forkId);
var currentFork = fork;
while (currentFork != null)
{
var forkPattern = KeyGenerator.GenerateForkValuePattern(AppId, currentFork.Id);
var keys = KeyValueStore.Keys($"{forkPattern}*");
foreach (var key in keys)
{
var originalKey = key.Substring(forkPattern.Length);
// If the key was used/deleted in a lower fork, this key is not relevant
if (usedKeys.Contains(originalKey) || deletedKeys.Contains(originalKey))
{
continue;
}
if (originalKey.EndsWith(KeyGenerator.NullKeyPostFix))
{
deletedKeys.Add(originalKey.Substring(0, originalKey.Length - KeyGenerator.NullKeyPostFix.Length));
}
else
{
var keyDataCollection = KeyValueStore.GetKeyData(key);
foreach (var keyData in keyDataCollection)
{
valuesToSet.Add(Tuple.Create(originalKey, keyData.Item1, keyData.Item2, keyData.Item3));
}
usedKeys.Add(originalKey);
}
}
currentFork = currentFork.Parent;
}
var newForkId = CreateFork("master", $"Pruned from {fork.Id}:{fork.Name}");
var wrapper = GetWrapper(newForkId);
foreach (var value in valuesToSet)
{
wrapper.Set(value.Item2, value.Item1, value.Item3, value.Item4);
}
return(newForkId);
}
public ForksWrapper(IKeyValueStore <TDataTypesEnum> keyValueStore,
int appId, int forkId, ForkProvider <TDataTypesEnum> forkProvider)
{
_keyValueStore = keyValueStore ?? throw new ArgumentNullException(nameof(keyValueStore));
_appId = appId;
if (!typeof(TDataTypesEnum).IsEnum)
{
throw new ArgumentException($"{nameof(TDataTypesEnum)} must be an enumerated type");
}
_forkProvider = forkProvider;
Fork = _forkProvider.GetFork(forkId);
_forkProvider.ForkChanged += _forkProvider_ForkChanged;
}
/// <summary>
/// Merge all the keys from one fork to another fork, a new fork is created from the target with the new data
/// </summary>
/// <param name="originForkId">Origin fork id</param>
/// <param name="targetForkId">Target fork id</param>
/// <returns>New fork id, Target fork id is the parent</returns>
public int MergeFork(int originForkId, int targetForkId)
{
var usedKeys = new HashSet <string>();
var valuesToSet = new List <Tuple <string, TDataTypesEnum, byte[], object> >();
var keysToDelete = new Dictionary <string, TDataTypesEnum>();
var currentFork = ForkProvider.GetFork(originForkId);
var targetFork = ForkProvider.GetFork(targetForkId);
while (!IsCommonParent(currentFork, targetFork))
{
if (currentFork == null)
{
throw new ArgumentException($"No common parents between {originForkId} and {targetForkId}");
}
var forkPattern = KeyGenerator.GenerateForkValuePattern(AppId, currentFork.Id);
var keys = KeyValueStore.Keys($"{forkPattern}*");
foreach (var key in keys)
{
var originalKey = key.Substring(forkPattern.Length);
// If the key was used/deleted in a lower fork, this key is not relevant
if (usedKeys.Contains(originalKey) || keysToDelete.ContainsKey(originalKey))
{
continue;
}
if (originalKey.EndsWith(KeyGenerator.NullKeyPostFix))
{
var type = (TDataTypesEnum)BinarySerializerHelper.DeserializeObject(KeyValueStore.Get(KeyValueStore.DefaultType, key, null));
keysToDelete.Add(originalKey.Substring(0, originalKey.Length - KeyGenerator.NullKeyPostFix.Length), type);
}
else
{
var keyDataCollection = KeyValueStore.GetKeyData(key);
foreach (var keyData in keyDataCollection)
{
valuesToSet.Add(Tuple.Create(originalKey, keyData.Item1, keyData.Item2, keyData.Item3));
}
usedKeys.Add(originalKey);
}
}
currentFork = currentFork.Parent;
}
var newForkId = CreateFork($"{targetFork.Name} Merge", "", targetFork.Id);
var wrapper = GetWrapper(newForkId);
foreach (var keyToDelete in keysToDelete)
{
wrapper.Delete(keyToDelete.Value, keyToDelete.Key);
}
foreach (var value in valuesToSet)
{
wrapper.Set(value.Item2, value.Item1, value.Item3, value.Item4);
}
return(newForkId);
}
