/// <summary>
/// Parses the RTable configuration blobs.
/// Returns the list of views, the list of configured tables and the lease duration.
/// If null is returned, then the value of tableConfigList/leaseDuration are not relevant.
/// </summary>
/// <param name="blobs"></param>
/// <param name="useHttps"></param>
/// <param name="tableConfigList"></param>
/// <param name="leaseDuration"></param>
/// <returns></returns>
public List <View> ParseBlob(
List <CloudBlockBlob> blobs,
Action <ReplicaInfo> SetConnectionString,
out List <ReplicatedTableConfiguredTable> tableConfigList,
out int leaseDuration,
out Guid configId)
{
tableConfigList = null;
leaseDuration = 0;
configId = Guid.Empty;
ReplicatedTableConfiguration configuration;
List <string> eTags;
ReplicatedTableQuorumReadResult result = CloudBlobHelpers.TryReadBlobQuorum(
blobs,
out configuration,
out eTags,
ReplicatedTableConfiguration.FromJson);
if (result.Code != ReplicatedTableQuorumReadCode.Success)
{
ReplicatedTableLogger.LogError("Unable to refresh views, \n{0}", result.ToString());
return(null);
}
/**
* Views:
*/
var viewList = new List <View>();
foreach (var entry in configuration.viewMap)
{
ReplicatedTableConfigurationStore configurationStore = entry.Value;
var view = View.InitFromConfigVer2(entry.Key, configurationStore, SetConnectionString);
view.RefreshTime = DateTime.UtcNow;
if (view.ViewId <= 0)
{
ReplicatedTableLogger.LogError("ViewId={0} of ViewName={1} is invalid. Must be >= 1.", view.ViewId, view.Name);
continue;
}
if (view.IsEmpty)
{
ReplicatedTableLogger.LogError("ViewName={0} is empty, skipping ...", view.Name);
continue;
}
// - ERROR!
if (view.ReadHeadIndex > view.TailIndex)
{
ReplicatedTableLogger.LogError("ReadHeadIndex={0} of ViewName={1} is out of range. Must be <= {2}", view.ReadHeadIndex, view.Name, view.TailIndex);
continue;
}
viewList.Add(view);
}
if (!viewList.Any())
{
ReplicatedTableLogger.LogError("Config has no active Views !");
return(null);
}
/**
* Tables:
*/
tableConfigList = configuration.tableList.ToList();
// - lease duration
leaseDuration = configuration.LeaseDuration;
// - ConfigId
configId = configuration.GetConfigId();
return(viewList);
}
public static ReplicatedTableQuorumWriteResult TryWriteBlobQuorum <T>(List <CloudBlockBlob> blobs, T configuration, Func <string, T> ParseBlobFunc, Func <T, T, bool> ConfigIdComparer, Func <T, T> GenerateConfigId)
where T : ReplicatedTableConfigurationBase, new()
{
// Fetch all blobs ...
List <T> valuesArray;
List <string> eTagsArray;
List <ReplicatedTableReadBlobResult> resultArray = TryReadAllBlobs(blobs, out valuesArray, out eTagsArray, ParseBlobFunc);
// Find majority ...
int quorumIndex;
ReplicatedTableQuorumReadResult majority = FindMajority(resultArray.AsReadOnly(), valuesArray.AsReadOnly(), out quorumIndex);
string readDetails = majority.ToString();
switch (majority.Code)
{
case ReplicatedTableQuorumReadCode.NotFound:
// Create blobs ...
break;
case ReplicatedTableQuorumReadCode.UpdateInProgress:
return(new ReplicatedTableQuorumWriteResult(ReplicatedTableQuorumWriteCode.ConflictDueToUpdateInProgress, readDetails));
case ReplicatedTableQuorumReadCode.Exception:
return(new ReplicatedTableQuorumWriteResult(ReplicatedTableQuorumWriteCode.ReadExceptions, readDetails));
case ReplicatedTableQuorumReadCode.NullOrLowSuccessRate:
return(new ReplicatedTableQuorumWriteResult(ReplicatedTableQuorumWriteCode.ReadNoQuorum, readDetails));
case ReplicatedTableQuorumReadCode.Success:
// Blob has changed since ...
if (ConfigIdComparer(valuesArray[quorumIndex], configuration) == false)
{
return(new ReplicatedTableQuorumWriteResult(ReplicatedTableQuorumWriteCode.ConflictDueToBlobChange, readDetails));
}
// Update blobs ...
break;
case ReplicatedTableQuorumReadCode.BlobsNotInSyncOrTransitioning:
return(new ReplicatedTableQuorumWriteResult(ReplicatedTableQuorumWriteCode.BlobsNotInSyncOrTransitioning, readDetails));
case ReplicatedTableQuorumReadCode.NullObject:
default:
{
var msg = string.Format("Unexpected value majority=\'{0}\' ", majority.Code);
throw new Exception(msg);
}
}
// Generate a new Id for the copy of the input configuration
T newConfiguration = GenerateConfigId(configuration);
string content = newConfiguration.ToString();
// Update blobs ...
int numberOfBlobs = blobs.Count;
ReplicatedTableWriteBlobResult[] writeResultArray = new ReplicatedTableWriteBlobResult[numberOfBlobs];
Parallel.For(0, numberOfBlobs, index =>
{
T currentValue = valuesArray[index];
string currentETag = eTagsArray[index];
if (currentValue == null)
{
currentETag = null;
}
else if (!ConfigIdComparer(currentValue, configuration))
{
currentETag = "*";
}
writeResultArray[index] = TryWriteBlob(blobs[index], content, currentETag);
});
int successRate = writeResultArray.Count(e => e.Success == true);
int quorum = (numberOfBlobs / 2) + 1;
if (successRate >= quorum)
{
// Return new config Id to the caller for record
string newConfId = newConfiguration.GetConfigId().ToString();
return(new ReplicatedTableQuorumWriteResult(ReplicatedTableQuorumWriteCode.Success, newConfId, writeResultArray.ToList()));
}
return(new ReplicatedTableQuorumWriteResult(ReplicatedTableQuorumWriteCode.QuorumWriteFailure, writeResultArray.ToList()));
}
/*
* Configuration management APIs
*/
public ReplicatedTableQuorumReadResult RetrieveConfiguration(out ReplicatedTableConfiguration configuration)
{
List <string> eTags;
ReplicatedTableQuorumReadResult
result = CloudBlobHelpers.TryReadBlobQuorum(
this.configManager.GetBlobs(),
out configuration,
out eTags,
ReplicatedTableConfiguration.FromJson);
if (result.Code != ReplicatedTableQuorumReadCode.Success)
{
ReplicatedTableLogger.LogError("Failed to read configuration, \n{0}", result.ToString());
}
return(result);
}
public void TurnReplicaOff(string storageAccountName)
{
if (string.IsNullOrEmpty(storageAccountName))
{
throw new ArgumentNullException("storageAccountName");
}
ReplicatedTableConfiguration configuration = null;
// - Retrieve configuration ...
ReplicatedTableQuorumReadResult readResult = RetrieveConfiguration(out configuration);
if (readResult.Code != ReplicatedTableQuorumReadCode.Success)
{
var msg = string.Format("TurnReplicaOff={0}: failed to read configuration, \n{1}", storageAccountName, readResult.ToString());
ReplicatedTableLogger.LogError(msg);
throw new Exception(msg);
}
// - Parse/Update all views ...
foreach (var viewConf in configuration.viewMap.Values)
{
var foundReplicas = viewConf.GetCurrentReplicaChain()
.FindAll(r => r.StorageAccountName == storageAccountName);
if (!foundReplicas.Any())
{
continue;
}
foreach (var replica in foundReplicas)
{
replica.Status = ReplicaStatus.None;
replica.ViewWhenTurnedOff = viewConf.ViewId;
}
// Update view id
viewConf.ViewId++;
}
// - Write back configuration ...
ReplicatedTableQuorumWriteResult writeResult = UpdateConfigurationInternal(configuration, true);
if (writeResult.Code != ReplicatedTableQuorumWriteCode.Success)
{
var msg = string.Format("TurnReplicaOff={0}: failed to update configuration, \n{1}", storageAccountName, writeResult.ToString());
ReplicatedTableLogger.LogError(msg);
throw new Exception(msg);
}
}
public void TurnReplicaOn(string storageAccountName, List <string> tablesToRepair, out List <ReplicatedTableRepairResult> failures)
{
if (string.IsNullOrEmpty(storageAccountName))
{
throw new ArgumentNullException("storageAccountName");
}
if (tablesToRepair == null)
{
throw new ArgumentNullException("tablesToRepair");
}
ReplicatedTableConfiguration configuration = null;
failures = new List <ReplicatedTableRepairResult>();
// - Retrieve configuration ...
ReplicatedTableQuorumReadResult readResult = RetrieveConfiguration(out configuration);
if (readResult.Code != ReplicatedTableQuorumReadCode.Success)
{
var msg = string.Format("TurnReplicaOn={0}: failed to read configuration, \n{1}", storageAccountName, readResult.ToString());
ReplicatedTableLogger.LogError(msg);
throw new Exception(msg);
}
/* - Phase 1:
* Move the *replica* to the front and set it to None.
* Make the view ReadOnly.
**/
#region Phase 1
configuration.MoveReplicaToHeadAndSetViewToReadOnly(storageAccountName);
// - Write back configuration, refresh its Id with the new one,
// but don't validate it is loaded bcz if all views of the config are empty, the config won't be refreshed by RefreshReadAndWriteViewsFromBlobs() thread!
SaveConfigAndRefreshItsIdAndValidateIsLoaded(configuration, "Phase 1", false);
#endregion
/**
* Chain is such: [None] -> [RO] -> ... -> [RO]
* or: [None] -> [None] -> ... -> [None]
**/
// - Wait for L + CF to make sure no pending transaction working on old views
Thread.Sleep(TimeSpan.FromSeconds(Constants.LeaseDurationInSec + Constants.ClockFactorInSec));
/* - Phase 2:
* Set the *replica* (head) to WriteOnly and other active replicas to ReadWrite.
* Or, in case of one replic chain
* Set only the *replica* (head) to ReadWrite.
**/
#region Phase 2
configuration.EnableWriteOnReplicas(storageAccountName);
// - Write back configuration, refresh its Id with the new one,
// and then validate it is loaded now (it has to be working since next Phase is "Repair")
SaveConfigAndRefreshItsIdAndValidateIsLoaded(configuration, "Phase 2");
#endregion
/**
* Chain is such: [W] -> [RW] -> ... -> [RW]
* or: [RW] -> [None] -> ... -> [None]
**/
// To be safe:
// - Wait for L + CF to make sure no pending transaction working on old views
Thread.Sleep(TimeSpan.FromSeconds(Constants.LeaseDurationInSec + Constants.ClockFactorInSec));
/* - Phase 3:
* Repair all tables
**/
#region Phase 3
foreach (var tableName in tablesToRepair)
{
ReplicatedTableRepairResult result = RepairTable(tableName, storageAccountName, configuration);
if (result.Code != ReplicatedTableRepairCode.Error)
{
ReplicatedTableLogger.LogInformational(result.ToString());
continue;
}
ReplicatedTableLogger.LogError(result.ToString());
// List of tables (and corresponding views) failed to repair!
failures.Add(result);
}
#endregion
/* - Phase 4:
* Set the *replica* (head) to ReadWrite.
**/
#region Phase 4
configuration.EnableReadWriteOnReplicas(storageAccountName, failures.Select(r => r.ViewName).ToList());
// - Write back configuration, refresh its Id with the new one,
// and then validate it is loaded now (i.e. it is a working config)
SaveConfigAndRefreshItsIdAndValidateIsLoaded(configuration, "Phase 4");
#endregion
/**
* Chain is such: [RW] -> [RW] -> ... -> [RW] if all configured table repaired
* or: [W] -> [RW] -> ... -> [RW] if at least one configured table failed repair !
**/
}
/// <summary>
/// Parses the RTable configuration blobs.
/// Returns the list of views, the list of configured tables and the lease duration.
/// If null is returned, then the value of tableConfigList/leaseDuration are not relevant.
/// </summary>
/// <param name="blobs"></param>
/// <param name="useHttps"></param>
/// <param name="tableConfigList"></param>
/// <param name="leaseDuration"></param>
/// <returns></returns>
public List <View> ParseBlob(
List <CloudBlockBlob> blobs,
Action <ReplicaInfo> SetConnectionString,
out List <ReplicatedTableConfiguredTable> tableConfigList,
out int leaseDuration,
out Guid configId)
{
tableConfigList = null;
leaseDuration = 0;
configId = Guid.Empty;
ReplicatedTableConfigurationStore configurationStore;
List <string> eTags;
ReplicatedTableQuorumReadResult result = CloudBlobHelpers.TryReadBlobQuorum(
blobs,
out configurationStore,
out eTags,
JsonStore <ReplicatedTableConfigurationStore> .Deserialize);
if (result.Code != ReplicatedTableQuorumReadCode.Success)
{
ReplicatedTableLogger.LogError("Unable to refresh view, \n{0}", result.ToString());
return(null);
}
/**
* View:
*/
var view = View.InitFromConfigVer1(DefaultViewName, configurationStore, SetConnectionString);
view.RefreshTime = DateTime.UtcNow;
if (view.ViewId <= 0)
{
ReplicatedTableLogger.LogError("ViewId={0} is invalid. Must be >= 1.", view.ViewId);
return(null);
}
if (view.IsEmpty)
{
ReplicatedTableLogger.LogError("ViewName={0} is empty, skipping ...", view.Name);
return(null);
}
/**
* Tables:
*/
tableConfigList = new List <ReplicatedTableConfiguredTable>
{
new ReplicatedTableConfiguredTable
{
TableName = AllTables,
ViewName = DefaultViewName,
ConvertToRTable = configurationStore.ConvertXStoreTableMode,
}
};
// - lease duration
leaseDuration = configurationStore.LeaseDuration;
return(new List <View> {
view
});
}
public void TurnReplicaOff(string storageAccountName)
{
if (string.IsNullOrEmpty(storageAccountName))
{
throw new ArgumentNullException("storageAccountName");
}
ReplicatedTableConfiguration configuration = null;
// - Retrieve configuration ...
ReplicatedTableQuorumReadResult readResult = RetrieveConfiguration(out configuration);
if (readResult.Code != ReplicatedTableQuorumReadCode.Success)
{
var msg = string.Format("TurnReplicaOff={0}: failed to read configuration, \n{1}", storageAccountName, readResult.ToString());
ReplicatedTableLogger.LogError(msg);
throw new Exception(msg);
}
// - Update all views ...
configuration.TurnReplicaOff(storageAccountName);
// - Write back configuration ...
ReplicatedTableQuorumWriteResult writeResult = UpdateConfigurationInternal(configuration, true);
if (writeResult.Code != ReplicatedTableQuorumWriteCode.Success)
{
var msg = string.Format("TurnReplicaOff={0}: failed to update configuration, \n{1}", storageAccountName, writeResult.ToString());
ReplicatedTableLogger.LogError(msg);
throw new Exception(msg);
}
}