private void AddPointerShards(DataElasticityEntities context, ShardSetConfig shardSetConfig)
{
foreach (var ps in shardSetConfig.Shards)
{
if (ps.PointerShardID == -1)
{
AddShardToShardSet(ps, shardSetConfig);
}
else
{
ModifyShard(ps);
}
}
var deleteShards =
context.Shards.Where(p => p.ShardSetID == shardSetConfig.ShardSetID);
foreach (var ps in deleteShards)
{
if (shardSetConfig.Shards.Count(x => x.PointerShardID == ps.ShardID) == 0)
{
context.Shards.Remove(ps);
}
}
}
private static void CompleteShardMapPublishingRequest(ShardSetConfig config,
ShardMapPublishingRequest shardMapPublishingRequest)
{
//todo: this is saving a whole'nother config rathr thanjust incrementing the "current" config map in force
config.CurrentPublishedShardMapID = shardMapPublishingRequest.NewShardMapID;
config.Save();
}
private static void ProcessShardMapPublishingRequest(ShardMapPublishingRequest shardMapPublishingRequest,
ShardSetConfig shardSetConfig)
{
var shardSetName = shardMapPublishingRequest.ShardSetName;
var shardSetConnectionDriver = GetShardSetConnectionDriver(shardSetName);
// to do - may need to page
var shardlets = shardSetConnectionDriver.GetShardlets(shardSetName);
foreach (var shardlet in shardlets)
{
// skip if shardlet is pinned
if (shardlet.Pinned)
{
continue;
}
// get the matching range shard for this shardlet based on the range map
var rangeShard =
shardSetConfig.ShardMap.Shards
.FirstOrDefault(rs => rs.HighDistributionKey > shardlet.DistributionKey);
// skip if we cannot find a range.
if (rangeShard == null)
{
continue;
}
// determine if the shardlet needs to be moved
if (rangeShard.ServerInstanceName == shardlet.ServerInstanceName &&
rangeShard.Catalog == shardlet.Catalog)
{
continue;
}
var request =
new ShardletMoveRequest
{
DestinationCatalog = rangeShard.Catalog,
DestinationServerInstanceName = shardlet.ServerInstanceName,
SourceCatalog = shardlet.Catalog,
SourceServerInstanceName = shardlet.ServerInstanceName,
DistributionKey = shardlet.DistributionKey,
ShardingKey = shardlet.ShardingKey,
ShardSetName = shardlet.ShardSetName,
DeleteOnMove = true,
Pin = false
};
request.Save();
}
// todo: do this save in parallel
//var parallelOptions = GetParallelOptions();
//Parallel.ForEach(shardletMoveRequests, parallelOptions,
// shardletMoveRequest => shardletMoveRequest.Save());
}
/// <summary>
/// Check the shard set action queues for the next request and, if found,
/// process the associated action off the queue.
/// </summary>
/// <param name="uniqueProcessID">A unique process identifier pass to the table driver to identify the caller.</param>
public virtual void CheckAndProcessQueue(Guid uniqueProcessID)
{
SendQueueProcessingEvent("Queue Processing Started");
//Get the next queue request in order of execution
var request = GetNextQueueRequest();
// identity the request type and call the appropriate method to handle the request
while (request != null)
{
switch (request.GetType().Name)
{
case _shardCreationRequest:
{
SendQueueProcessingEvent(_shardCreationRequest, request);
ShardSetConfig.HandleShardCreationRequest(request as ShardCreationRequest, this);
break;
}
case _shardMapPublishingRequest:
{
SendQueueProcessingEvent(_shardMapPublishingRequest, request);
ShardSetConfig.HandleShardMapPublishingRequest(request as ShardMapPublishingRequest,
this);
break;
}
case _shardletMoveRequest:
{
SendQueueProcessingEvent(_shardletMoveRequest, request);
Shardlet.HandleShardletMoveRequest(request as ShardletMoveRequest, this, uniqueProcessID);
break;
}
case _shardDeletionRequest:
{
SendQueueProcessingEvent(_shardDeletionRequest, request);
ShardSetConfig.HandleShardDeletionRequest(request as ShardDeletionRequest, this);
break;
}
case _shardMapSyncRequest:
{
SendQueueProcessingEvent(_shardMapSyncRequest, request);
ShardSetConfig.HandleShardSyncRequest(request as ShardSyncRequest, this);
break;
}
}
request = GetNextQueueRequest();
}
SendQueueProcessingEvent("Queue Processing Completed");
}
public IList <Shard> GetShardsForShardSet(
ShardSetConfig shardSetConfig)
{
using (var context = GetConnection(ConnectionString))
{
return(context.Shards.Where(ps => ps.ShardSetID == shardSetConfig.ShardSetID)
.Select(ps =>
new Shard
{
Catalog = ps.Database.DatabaseName,
Description = ps.Description,
ServerInstanceName = ps.Database.Server.ServerName,
PointerShardID = ps.ShardID
})
.ToList());
}
}
public ShardSetConfig GetShardSetConfigLatestVersion(string shardSetName)
{
ShardSetConfig returnVal = null;
using (var context = GetConnection(ConnectionString))
{
var shardSetConfig =
context.ShardSetConfigs
.Where(x => x.ShardSet.Name == shardSetName)
.OrderByDescending(x => x.Version)
.FirstOrDefault();
if (shardSetConfig != null)
{
returnVal = MakeShardSetConfig(shardSetConfig);
}
}
return(returnVal);
}
public Shard AddShardToShardSet(
Shard shard, ShardSetConfig shardSetConfig)
{
using (var context = GetConnection(ConnectionString))
{
var dbShard = new Models.Shard
{
Database =
context.Databases
.FirstOrDefault(
d =>
d.DatabaseName == shard.Catalog &&
d.Server.ServerName == shard.ServerInstanceName),
Description = shard.Description,
ShardSet =
context.ShardSets
.FirstOrDefault(tg => tg.ShardSetID == shardSetConfig.ShardSetID)
};
if (dbShard.Database == null)
{
dbShard.Database =
new Database
{
DatabaseName = shard.Catalog,
Server =
context.Servers.FirstOrDefault(s => s.ServerName == shard.ServerInstanceName),
};
context.Databases.Add(dbShard.Database);
}
context.Shards.Add(dbShard);
context.SaveChanges();
shard.PointerShardID = dbShard.ShardID;
}
return(shard);
}
private static IShardSetDriver GetShardSetDriver(ShardSetConfig config)
{
return(ScaleOutConfigManager.GetManager().GetShardSetDriver(config));
}
private ShardSetConfig MakeShardSetConfig(Models.ShardSetConfig shardSetConfigModel)
{
var shardSetConfig =
new ShardSetConfig
{
ShardSetConfigID = shardSetConfigModel.ShardSetConfigID,
ShardSetID = shardSetConfigModel.ShardSetID,
AllowDeployments = shardSetConfigModel.AllowDeployment,
CurrentShardCount = shardSetConfigModel.ShardMap.RangeShards.Count(),
MaxShardCount = shardSetConfigModel.MaxShardCount,
MaxShardSizeMb = shardSetConfigModel.MaxShardSizeMB,
MaxShardletsPerShard = shardSetConfigModel.MaxShardletsPerShard,
MinShardSizeMb = shardSetConfigModel.MinShardSizeMB,
TargetShardCount = shardSetConfigModel.TargetShardCount,
Version = shardSetConfigModel.Version,
ShardSetName = shardSetConfigModel.ShardSet.Name,
CurrentPublishedShardMapID = shardSetConfigModel.ShardSet.CurrentShardMapID,
ShardMap = new ShardMap
{
ShardMapID = shardSetConfigModel.ShardMapID,
Shards =
shardSetConfigModel.ShardMap.RangeShards
.Select(s =>
new RangeShard
{
ServerInstanceName = s.Database.Server.ServerName,
Catalog = s.Database.DatabaseName,
HighDistributionKey = s.RangeHighValue,
LowDistributionKey = s.RangeLowValue,
ShardID = s.ShardID
})
.ToList()
},
Shards = shardSetConfigModel.ShardSet.Shards
.Select(x =>
new Shard
{
Catalog = x.Database.DatabaseName,
ServerInstanceName = x.Database.Server.ServerName,
Description = x.Description,
PointerShardID = x.ShardID
})
.ToList(),
Servers = shardSetConfigModel.ShardSet.Servers
.Select(x =>
new Server
{
ServerID = x.ServerID,
ServerInstanceName = x.ServerName,
MaxShardsAllowed = x.MaxShardsAllowed,
AvailableShards = x.MaxShardsAllowed - x.Databases.Count
//TODO : Change to databases that are deployed or planned.. not all databases in history
})
.ToList(),
ShardSetConfigSettings = shardSetConfigModel.ShardSetConfigSettings
.Select(x =>
new DataElasticity.Models.ShardSetConfigSetting
{
ShardSetConfigSettingID = x.ShardSetConfigSettingID,
ShardSetConfigID = x.ShardSetConfigID,
SettingKey = x.SettingKey,
SettingValue = x.SettingValue
})
.ToList(),
};
return(shardSetConfig);
}
public ShardSetConfig AddShardSetConfig(
ShardSetConfig shardSetConfig)
{
using (var context = GetConnection(ConnectionString))
{
using (var scope = new TransactionScope())
{
ShardSet shardSet;
// Locate the associated shard set either by the key or the shard set name
// If it does not exist, create and save it.
// Check to see if they gave us a ShardSetID
if (shardSetConfig.ShardSetID == -1)
{
// Lets try to look it up by Name
shardSet =
context.ShardSets.FirstOrDefault(x => x.Name == shardSetConfig.ShardSetName);
//If it doesn't exist create it.
if (shardSet == null)
{
shardSet =
new ShardSet
{
Name = shardSetConfig.ShardSetName
};
context.ShardSets.Add(shardSet);
}
}
else
{
shardSet =
context.ShardSets.FirstOrDefault(
x => x.ShardSetID == shardSetConfig.ShardSetID);
if (shardSet == null)
{
throw new InvalidOperationException(string.Format("Shard Set ID {0} does not exist",
shardSetConfig.ShardSetID));
}
}
// if the configuration is being saved with a new Id, record it on the config table
if (shardSetConfig.CurrentPublishedShardMapID.HasValue)
{
shardSet.CurrentShardMapID = shardSetConfig.CurrentPublishedShardMapID;
}
// Nuke the server list because we are going to reload it from the configuration
shardSet.Servers.Clear();
//Now read the servers
foreach (var server in shardSetConfig.Servers)
{
//is the server new?
if (server.ServerID == -1)
{
server.Save();
}
//Lets grab the server object from the DB.
var dbServer = context.Servers.FirstOrDefault(x => x.ServerID == server.ServerID);
if (dbServer == null)
{
throw new Exception("Server not found in the config database");
}
shardSet.Servers.Add(dbServer);
}
if (shardSetConfig.ShardMap.ShardMapID == -1)
{
shardSetConfig.ShardMap = AddShardMap(shardSetConfig.ShardMap, context);
}
var dbShardSetConfig =
new Models.ShardSetConfig
{
AllowDeployment = shardSetConfig.AllowDeployments,
MaxShardCount = shardSetConfig.MaxShardCount,
MaxShardSizeMB = shardSetConfig.MaxShardSizeMb,
MaxShardletsPerShard = shardSetConfig.MaxShardletsPerShard,
MinShardSizeMB = shardSetConfig.MinShardSizeMb,
TargetShardCount = shardSetConfig.TargetShardCount,
ShardMapID = shardSetConfig.ShardMap.ShardMapID,
ShardSet = shardSet,
Version = (shardSet.ShardSetConfigs.Count() + 1)
};
// create settings on the new configuration
foreach (var shardSetConfigSetting in shardSetConfig.ShardSetConfigSettings)
{
var setting = new ShardSetConfigSetting
{
SettingKey = shardSetConfigSetting.SettingKey,
SettingValue = shardSetConfigSetting.SettingValue,
ShardSetConfig = dbShardSetConfig
};
dbShardSetConfig.ShardSetConfigSettings.Add(setting);
}
context.ShardSetConfigs.Add(dbShardSetConfig);
context.SaveChanges();
shardSetConfig.ShardSetConfigID = dbShardSetConfig.ShardSetConfigID;
shardSetConfig.ShardSetID = shardSet.ShardSetID;
AddPointerShards(context, shardSetConfig);
scope.Complete();
}
}
return(shardSetConfig);
}
/// <summary>
/// Moves to shard.
/// </summary>
/// <param name="shard">The shard to move the ShardLet data to.</param>
/// <param name="pin">if set to <c>true</c> add the shard to the pinned shard list.</param>
/// <param name="deleteOnMove">if set to <c>true</c> delete the Shardlet data from the existing Shard after move.</param>
/// <param name="uniqueProcessID">A unique process identifier that can be set to maintain state between moves.</param>
/// <param name="queueRequest">if set to <c>true</c> queue the shard move rather than executing it immediately.</param>
public void MoveToShard(ShardBase shard, bool pin, bool deleteOnMove, Guid uniqueProcessID,
bool queueRequest = false)
{
if (queueRequest)
{
var request =
new ShardletMoveRequest
{
DestinationCatalog = shard.Catalog,
DestinationServerInstanceName = shard.ServerInstanceName,
SourceCatalog = Catalog,
SourceServerInstanceName = ServerInstanceName,
DistributionKey = DistributionKey,
ShardingKey = ShardingKey,
ShardSetName = ShardSetName,
DeleteOnMove = deleteOnMove,
UniqueProcessID = uniqueProcessID,
Pin = pin
};
request.Save();
return;
}
var shardSetConnectionDriver = ScaleOutShardletManager.GetManager().GetShardletConnectionDriver(ShardSetName);
try
{
// change the state to read only in the map and update th epin status
Status = ShardletStatus.Moving;
Pinned = pin;
shardSetConnectionDriver.PublishShardlet(this);
// terminate all existing connections
shardSetConnectionDriver.TerminateConnections(this);
// copy the shardlet data
var shardSetConfig = ShardSetConfig.LoadCurrent(ShardSetName);
var currentShard =
new RangeShard
{
Catalog = Catalog,
ServerInstanceName = ServerInstanceName,
};
shardSetConfig.CopyShardlet(currentShard, shard, ShardingKey, uniqueProcessID);
// update the status and set the new catalog and instance in the shard map
Catalog = shard.Catalog;
ServerInstanceName = shard.ServerInstanceName;
Status = ShardletStatus.Active;
shardSetConnectionDriver.PublishShardlet(this);
if (deleteOnMove)
{
shardSetConfig.DeleteShardlet(currentShard, ShardingKey);
}
}
catch (Exception)
{
Status = ShardletStatus.Active;
shardSetConnectionDriver.PublishShardlet(this);
throw;
}
}
