private static TableQuery BuildQuery(string channelId, string conversationId, DateTime oldest)
{
var query = new TableQuery();
string filter = null;
if (channelId != null && conversationId != null)
{
var pkey = ActivityEntity.GeneratePartitionKey(channelId, conversationId);
filter = TableQuery.GenerateFilterCondition(TableConstants.PartitionKey, QueryComparisons.Equal, pkey);
}
else if (channelId != null)
{
var pkey = ActivityEntity.GeneratePartitionKey(channelId, "");
filter = TableQuery.GenerateFilterCondition(TableConstants.PartitionKey, QueryComparisons.GreaterThanOrEqual, pkey);
}
if (oldest != default(DateTime))
{
var rowKey = ActivityEntity.GenerateRowKey(oldest);
var rowFilter = TableQuery.GenerateFilterCondition(TableConstants.RowKey, QueryComparisons.GreaterThanOrEqual, rowKey);
if (filter == null)
{
filter = rowFilter;
}
else
{
filter = TableQuery.CombineFilters(filter, TableOperators.And, rowFilter);
}
}
if (filter != null)
{
query.Where(filter);
}
return(query);
}
/// <summary>
/// Delete any conversation records older than <paramref name="oldest"/>.
/// </summary>
/// <param name="oldest">Maximum timespan from now to remember.</param>
/// <param name="cancel">Cancellation token.</param>
async Task IActivityManager.DeleteBeforeAsync(DateTime oldest, CancellationToken cancel)
{
var rowKey = ActivityEntity.GenerateRowKey(oldest);
var query = new TableQuery <ActivityEntity>()
.Where(TableQuery.GenerateFilterCondition(TableConstants.RowKey, QueryComparisons.LessThan, rowKey))
.Select(new string[] { TableConstants.PartitionKey, TableConstants.RowKey });
await DeleteAsync(query, cancel);
}