/// <inheritdoc />
public Task <MessageJournalPosition> GetBeginningOfJournal(CancellationToken cancellationToken = new CancellationToken())
{
var id = new ObjectId(0, 0, 0, 0);
var pos = new MongoDBMessageJournalPosition(id);
return(Task.FromResult <MessageJournalPosition>(pos));
}
/// <inheritdoc />
public async Task <MessageJournalReadResult> Read(MessageJournalPosition start, int count, MessageJournalFilter filter = null,
CancellationToken cancellationToken = new CancellationToken())
{
var fb = Builders <MessageJournalEntryDocument> .Filter;
var filterDef = fb.Gte(mje => mje.Id, ((MongoDBMessageJournalPosition)start).Id);
filterDef = BuildFilter(filter, filterDef, fb);
var options = new FindOptions();
if (_collationSupported)
{
options.Collation = _collation;
}
var entryDocuments = await _messageJournalEntries.Find(filterDef, options)
.Limit(count + 1)
.ToListAsync(cancellationToken);
var endOfJournal = entryDocuments.Count <= count;
var nextId = entryDocuments.Select(e => e.Id).LastOrDefault();
if (endOfJournal)
{
nextId = new ObjectId(nextId.Timestamp, nextId.Machine, nextId.Pid, nextId.Increment + 1);
}
var nextPosition = new MongoDBMessageJournalPosition(nextId);
var entries = new List <MessageJournalEntry>();
foreach (var entryDocument in entryDocuments.Take(count))
{
var position = new MongoDBMessageJournalPosition(entryDocument.Id);
var timestamp = entryDocument.Timestamp;
var category = entryDocument.Category;
var headers = new MessageHeaders(entryDocument.Headers);
var message = new Message(headers, entryDocument.Content);
entries.Add(new MessageJournalEntry(category, position, timestamp, message));
}
return(new MessageJournalReadResult(start, nextPosition, endOfJournal, entries));
}
/// <inheritdoc />
public MessageJournalPosition ParsePosition(string str)
{
return(MongoDBMessageJournalPosition.Parse(str));
}
