public static async Task <PagedResult <TEntity> > GetPagedQueryResultsAsync <TEntity>(
this IDynamoDBContext dynamoDbContext, QueryOperationConfig queryConfig) where TEntity : class
{
var dbResults = new List <TEntity>();
var table = dynamoDbContext.GetTargetTable <TEntity>();
var search = table.Query(queryConfig);
var resultsSet = await search.GetNextSetAsync().ConfigureAwait(false);
var paginationToken = search.PaginationToken;
if (resultsSet.Any())
{
dbResults.AddRange(dynamoDbContext.FromDocuments <TEntity>(resultsSet));
// Look ahead for any more, but only if we have a token
if (!string.IsNullOrEmpty(PaginationDetails.EncodeToken(paginationToken)))
{
queryConfig.PaginationToken = paginationToken;
queryConfig.Limit = 1;
search = table.Query(queryConfig);
resultsSet = await search.GetNextSetAsync().ConfigureAwait(false);
if (!resultsSet.Any())
{
paginationToken = null;
}
}
}
return(new PagedResult <TEntity>(dbResults, new PaginationDetails(paginationToken)));
}
public async Task <IEnumerable <CelebrityEventBase> > ReadEventsAsync(string aggregateId, long?version = null, bool consistentRead = false, CancellationToken cancellationToken = default)
{
if (aggregateId is null)
{
throw new ArgumentNullException(nameof(aggregateId));
}
var table = _dbContext.GetTargetTable <DynamoDbEventModel>(_configuration);
var search = table.Query(new QueryOperationConfig
{
KeyExpression = new Expression
{
ExpressionStatement = "#aggregate_id = :v_aggregate_id and #aggregate_version >= :v_aggregate_version",
ExpressionAttributeNames = new Dictionary <string, string>
{
{ "#aggregate_id", "AggregateId" },
{ "#aggregate_version", "AggregateVersion" }
},
ExpressionAttributeValues = new Dictionary <string, DynamoDBEntry>
{
{ ":v_aggregate_id", aggregateId },
{ ":v_aggregate_version", version ?? 1 }
},
},
IndexName = _options.IndexName,
ConsistentRead = consistentRead
});
var events = new List <DynamoDbEventModel>();
do
{
var items = await search.GetNextSetAsync(cancellationToken);
if (items.Any())
{
events.AddRange(_dbContext.FromDocuments <DynamoDbEventModel>(items));
}
}while(search.IsDone is false);
return(ParseToCelebrityEvents(events));
}
public async Task <PagedResult <Note> > GetByTargetIdAsync(GetNotesByTargetIdQuery query)
{
int pageSize = query.PageSize.HasValue ? query.PageSize.Value : MAX_RESULTS;
var dbNotes = new List <NoteDb>();
var table = _dynamoDbContext.GetTargetTable <NoteDb>();
var queryConfig = new QueryOperationConfig
{
IndexName = GETNOTESBYTARGETIDINDEX,
BackwardSearch = true,
ConsistentRead = true,
Limit = pageSize,
PaginationToken = PaginationDetails.DecodeToken(query.PaginationToken),
Filter = new QueryFilter(TARGETID, QueryOperator.Equal, query.TargetId)
};
var search = table.Query(queryConfig);
_logger.LogDebug($"Querying {queryConfig.IndexName} index for targetId {query.TargetId}");
var resultsSet = await search.GetNextSetAsync().ConfigureAwait(false);
var paginationToken = search.PaginationToken;
if (resultsSet.Any())
{
dbNotes.AddRange(_dynamoDbContext.FromDocuments <NoteDb>(resultsSet));
// Look ahead for any more, but only if we have a token
if (!string.IsNullOrEmpty(PaginationDetails.EncodeToken(paginationToken)))
{
queryConfig.PaginationToken = paginationToken;
queryConfig.Limit = 1;
search = table.Query(queryConfig);
resultsSet = await search.GetNextSetAsync().ConfigureAwait(false);
if (!resultsSet.Any())
{
paginationToken = null;
}
}
}
return(new PagedResult <Note>(dbNotes.Select(x => x.ToDomain()), new PaginationDetails(paginationToken)));
}
