public void ReadMessages(long from, long till, int maxCount, Action <MessageWithId> action)
{
Require.ZeroOrGreater("from", from);
Require.ZeroOrGreater("maxOffset", till);
Require.Positive("maxCount", maxCount);
var count = 0;
using (var prs = new PageReadStream(Messages, from, till, _buffer))
{
using (var bin = new BinaryReader(prs))
{
while (prs.Position < prs.Length)
{
var message = StorageFormat.Read(bin);
action(message);
count += 1;
if (count >= maxCount)
{
break;
}
}
}
}
}
public MessageResult ReadMessages(long from, long till, int maxCount)
{
Require.ZeroOrGreater("from", from);
Require.ZeroOrGreater("maxOffset", till);
Require.Positive("maxCount", maxCount);
var list = new List <MessageWithId>(maxCount);
var position = from;
using (var prs = new PageReadStream(Messages, from, till, _buffer)) {
using (var bin = new BinaryReader(prs)) {
while (prs.Position < prs.Length)
{
var message = StorageFormat.Read(bin);
list.Add(message);
position = prs.Position;
if (list.Count >= maxCount)
{
break;
}
}
}
}
return(new MessageResult(list, position));
}
void RunSubscription(
Subscription sub,
long position,
CancellationToken ct,
int bufferSize,
int cacheSize
)
{
sub.DebugStartPosition = position;
var buffer = new byte[bufferSize];
// forever try
while (!ct.IsCancellationRequested)
{
try {
// read current max length
var length = Position.Read();
sub.DebugKnownMaxOffset = length;
using (var prs = new PageReadStream(Messages, position, length, buffer)) {
using (var bin = new BinaryReader(prs)) {
while (prs.Position < prs.Length)
{
var message = StorageFormat.Read(bin);
sub.Buffer.Enqueue(message);
sub.DebugEnqueuedOffset = prs.Position;
position = prs.Position;
while (sub.Buffer.Count >= cacheSize)
{
ct.WaitHandle.WaitOne(500);
}
}
}
}
// wait till we get chance to advance
while (Position.Read() == position)
{
if (ct.WaitHandle.WaitOne(1000))
{
return;
}
}
}
catch (ForbiddenException) {
throw;
}
catch (Exception ex) {
Debug.Print("Exception {0}", ex);
ct.WaitHandle.WaitOne(1000 * 5);
}
}
}
public AppendResult Append(ICollection <Message> messages)
{
if (messages.Count == 0)
{
throw new ArgumentException("Must provide non-empty array", "messages");
}
var ids = new List <MessageId>(messages.Count);
foreach (var item in messages)
{
if (item.Value.Length > Constants.MaxValueSize)
{
string message = "Each message must be smaller than " + Constants.MaxValueSize;
throw new InvalidOperationException(message);
}
if (item.Key.Length > Constants.MaxKeySize)
{
var message = "Each contract must be shorter than " + Constants.MaxKeySize;
throw new InvalidOperationException(message);
}
var sizeEstimate = StorageFormat.EstimateSize(item);
var availableInBuffer = _stream.Length - _stream.Position;
if (sizeEstimate > availableInBuffer)
{
FlushBuffer();
}
var offset = VirtualPosition();
var id = MessageId.CreateNew(offset);
StorageFormat.Write(_binary, id, item);
ids.Add(id);
}
FlushBuffer();
_positionWriter.Update(_position);
return(new AppendResult(ids, _position));
}
