private const double EVENT_FROM_TIMEOUT = 30; // 30 seconds
/// <summary>
/// Gets all objects from the server. Used in order to fill the cache.
/// This function implements the new event system, available from in API version 1.9.
/// In the new event system, (GetAllRecords + GetEvents) sequence will replace (RegisterForEvents + DownloadObjects + GetNextEvents).
/// </summary>
/// <param name="session">The session over which to download the objects. Must not be null.</param>
/// <param name="changes">The queue that the ObjectChanges will be put into. Must not be null.</param>
/// <param name="cancelled">Used by GetEvents().</param>
/// <param name="token">Used by GetEvents().</param>
public static void GetAllObjects(Session session, LockFreeQueue <ObjectChange> changes, HTTP.FuncBool cancelled, ref string token)
{
// download objects that are not covered by event.from(), e.g. Roles
var roleRecords = Role.get_all_records(session);
foreach (KeyValuePair <XenRef <Role>, Role> entry in roleRecords)
{
changes.Enqueue(new ObjectChange(typeof(Role), entry.Key.opaque_ref, entry.Value));
}
// get all objects with event.from()
token = "";
GetEvents(session, changes, cancelled, ref token);
}
/// <summary>
/// Blocks until events are sent on the session, or timeout is reached, then processes any received events and adds them
/// to eventQueue. This function implements the new event system, available in API version 1.9.
/// In the new event system, (GetAllRecords + GetEvents) sequence will replace (RegisterForEvents + DownloadObjects + GetNextEvents).
/// </summary>
/// <param name="session"></param>
/// <param name="eventQueue"></param>
/// <param name="cancelled"></param>
/// <param name="token">A token used by event.from().
/// It should be the empty string when event.from is first called, which is the replacement of get_all_records.
/// </param>
public static void GetEvents(Session session, LockFreeQueue <ObjectChange> eventQueue, HTTP.FuncBool cancelled, ref string token)
{
Proxy_Event[] proxyEvents;
try
{
var classes = new [] { "*" }; // classes that we are interested in receiving events from
var eventResult = Event.from(session, classes, token, EVENT_FROM_TIMEOUT);
token = eventResult.token;
proxyEvents = eventResult.events;
}
catch (WebException e)
{
// Catch timeout, and turn it into an EventFromBlockedException so we can recognise it later (CA-33145)
if (e.Status == WebExceptionStatus.Timeout)
{
throw new EventFromBlockedException();
}
else
{
throw;
}
}
if (cancelled())
{
return;
}
//We want to do the marshalling on this bg thread so as not to block the gui thread
foreach (Proxy_Event proxyEvent in proxyEvents)
{
ObjectChange objectChange = ProcessEvent(proxyEvent);
if (objectChange != null)
{
eventQueue.Enqueue(objectChange);
}
}
}
public LockFreeQueueEnumerator(LockFreeQueue <U> queue)
{
this.queue = queue;
this.current = queue.head;
}
/// <summary>
/// Blocks until events are sent on the session, or timeout is reached, then processes any received events and adds them
/// to eventQueue. This function implements the new event system, available in API version 1.9.
/// In the new event system, (GetAllRecords + GetEvents) sequence will replace (RegisterForEvents + DownloadObjects + GetNextEvents).
/// </summary>
/// <param name="session"></param>
/// <param name="eventQueue"></param>
/// <param name="cancelled"></param>
/// <param name="token">A token used by event.from().
/// It should be the empty string when event.from is first called, which is the replacement of get_all_records.
/// </param>
public static void GetEvents(Session session, LockFreeQueue <ObjectChange> eventQueue, HTTP.FuncBool cancelled, ref string token)
{
Proxy_Event[] proxyEvents = {};
Event[] events = {};
try
{
var classes = new [] { "*" }; // classes that we are interested in receiving events from
var eventResult = Event.from(session, classes, token, EVENT_FROM_TIMEOUT);
if (session.JsonRpcClient != null)
{
var batch = (EventBatch)eventResult;
events = batch.events;
token = batch.token;
}
else
{
var evts = (Events)eventResult;
proxyEvents = evts.events;
token = evts.token;
}
}
catch (WebException e)
{
// Catch timeout, and turn it into an EventFromBlockedException so we can recognise it later (CA-33145)
if (e.Status == WebExceptionStatus.Timeout)
{
throw new EventFromBlockedException();
}
else
{
throw;
}
}
if (cancelled())
{
return;
}
//We want to do the marshalling on this background thread so as not to block the gui thread
if (session.JsonRpcClient != null)
{
foreach (Event evt in events)
{
var objectChange = ProcessEvent(evt.class_, evt.operation, evt.opaqueRef, evt.snapshot, false);
if (objectChange != null)
{
eventQueue.Enqueue(objectChange);
}
}
}
else
{
foreach (Proxy_Event proxyEvent in proxyEvents)
{
var objectChange = ProcessEvent(proxyEvent.class_, proxyEvent.operation, proxyEvent.opaqueRef, proxyEvent.snapshot, true);
if (objectChange != null)
{
eventQueue.Enqueue(objectChange);
}
}
}
}
