/// <summary>
/// This will execute a DocumentDB query in the form of an IQueryable (Linq form) and return the results.
///
/// It handles paging, continuation tokens, and retriable errors such as "too many requests" for you,
/// while aggregating all query results in-memory before returning.
/// </summary>
/// <typeparam name="R"></typeparam>
/// <param name="queryable"></param>
/// <param name="queryExecutionHandler"></param>
/// <param name="enumerationExceptionHandler"></param>
/// <param name="feedResponseHandler"></param>
/// <param name="maxRetries"></param>
/// <param name="maxTime"></param>
/// <param name="shouldRetry"></param>
/// <returns></returns>
public static async Task <IList <R> > ExecuteQueryWithContinuationAndRetry <R>(IQueryable <R> queryable, QueryExecutionHandler queryExecutionHandler, EnumerationExceptionHandler enumerationExceptionHandler, FeedResponseHandler feedResponseHandler, int maxRetries, TimeSpan maxTime, ShouldRetry shouldRetry)
{
IDocumentQuery <R> query = null;
try
{
query = queryable.AsDocumentQuery();
}
catch (Exception e)
{
throw new ArgumentException(BadQueryableMessage, e);
}
var context = new FeedResponseContext();
queryExecutionHandler(context, query.ToString());
feedResponseHandler(context, FeedResponseType.BeforeEnumeration, null);
var allResults = new List <R>();
while (query.HasMoreResults)
{
FeedResponse <R> intermediateResponse = null;
try
{
intermediateResponse = await DocumentDbReliableExecution.ExecuteResultWithRetry(() =>
query.ExecuteNextAsync <R>(),
null,
maxRetries,
maxTime,
shouldRetry);
}
catch (Exception ex)
{
bool handled = enumerationExceptionHandler(context, ex);
if (!handled)
{
feedResponseHandler(context, FeedResponseType.EnumerationAborted, null);
throw;
}
else
{
break;
}
}
// lots of interesting info in intermediateResults such as RU usage, etc.
List <R> intermediateResults = intermediateResponse.ToList();
UpdateContext <R>(context, intermediateResponse, JsonConvert.SerializeObject(intermediateResults).Length, query.HasMoreResults);
feedResponseHandler(context, FeedResponseType.PageReceived, new FeedResponseWrapper <R>(intermediateResponse));
allResults.AddRange(intermediateResults);
}
feedResponseHandler(context, FeedResponseType.AfterEnumeration, null);
return(allResults);
}
public string Build()
{
var expressionObj = JObject.Parse(_query.ToString());
var sql = expressionObj["query"].Value <string>();
var regex = new Regex(ArrayContainsRegEx);
return(regex.Replace(sql, MatchEval));
}
/// <summary>
/// Executes the specified <see cref="IDocumentQuery{T}"/> asynchronously.
/// </summary>
/// <typeparam name="T">The result type.</typeparam>
/// <param name="query">The query to execute.</param>
/// <returns>The array of records returned by the query.</returns>
protected async Task <T[]> ExecutedQueryAsync <T>(IDocumentQuery <T> query)
{
var result = new List <T>();
double requestCharge = 0;
while (query.HasMoreResults)
{
FeedResponse <T> queryResponse = await query.ExecuteNextAsync <T>();
result.AddRange(queryResponse.ToArray());
requestCharge += queryResponse.RequestCharge;
}
Log.LogInformation($"Query '{this.UnescapeQuotes(query.ToString())}', cost {requestCharge} RUs");
return(result.ToArray());
}
internal static async Task <DocumentsPage <R> > BeginPagingWithRetry <R>(IDocumentQuery <R> query, QueryExecutionHandler queryExecutionHandler, EnumerationExceptionHandler enumerationExceptionHandler, FeedResponseHandler feedResponseHandler, int maxRetries, TimeSpan maxTime, ShouldRetry shouldRetry)
{
var context = MakeFirstContextForPaging(query);
queryExecutionHandler(context, query.ToString());
feedResponseHandler(context, FeedResponseType.BeforeEnumeration, null);
FeedResponse <R> firstPageResponse = null;
while (firstPageResponse == null)
{
try
{
firstPageResponse = await DocumentDbReliableExecution.ExecuteResultWithRetry(() =>
query.ExecuteNextAsync <R>(),
null,
maxRetries,
maxTime,
shouldRetry);
}
catch (Exception ex)
{
bool handled = enumerationExceptionHandler(context, ex);
if (!handled)
{
feedResponseHandler(context, FeedResponseType.EnumerationAborted, null);
throw;
}
}
}
// lots of interesting info in intermediateResults such as RU usage, etc.
List <R> firstPageResults = firstPageResponse.ToList();
UpdateContext(context, firstPageResponse, JsonConvert.SerializeObject(firstPageResults).Length, query.HasMoreResults);
feedResponseHandler(context, FeedResponseType.PageReceived, new FeedResponseWrapper <R>(firstPageResponse));
if (!query.HasMoreResults)
{
DeletePagingContext(query);
}
return(new DocumentsPage <R>(firstPageResults, query.HasMoreResults ? firstPageResponse.ResponseContinuation : null));
}
public async Task <IEnumerable <T> > GetItemsAsync(Expression <Func <T, bool> > predicate, string partitionKey = null)
{
var feedOptions = new FeedOptions {
MaxItemCount = -1, PopulateQueryMetrics = true
};
if (string.IsNullOrEmpty(partitionKey))
{
feedOptions.EnableCrossPartitionQuery = true;
System.Diagnostics.Debug.WriteLine("Executing Query without PartitionKey");
}
else
{
System.Diagnostics.Debug.WriteLine("Executing Query with PartitionKey");
feedOptions.PartitionKey = new PartitionKey(partitionKey);
}
IDocumentQuery <T> query = _client.CreateDocumentQuery <T>(
UriFactory.CreateDocumentCollectionUri(_cosmosContainerSettings.DatabaseId1, _cosmosContainerSettings.CollectionId), feedOptions)
.Where(predicate)
.AsDocumentQuery();
System.Diagnostics.Debug.WriteLine($"Query: {query.ToString()}");
List <T> results = new List <T>();
while (query.HasMoreResults)
{
var response = await query.ExecuteNextAsync <T>();
System.Diagnostics.Debug.WriteLine($"{response.RequestCharge}RU");
System.Diagnostics.Debug.WriteLine("QueryMetrics:");
System.Diagnostics.Debug.WriteLine(response.QueryMetrics.FirstOrDefault());
results.AddRange(response);
}
return(results);
}
private static async Task <List <T> > GetResultsFromQueryToList <T>(IDocumentQuery <T> query, CancellationToken cancellationToken)
{
var results = new List <T>();
while (query.HasMoreResults)
{
var items = await query.InvokeExecuteNextAsync(() => query.ExecuteNextAsync <T>(cancellationToken), query.ToString()).ExecuteCosmosCommand();
results.AddRange(items);
}
return(results);
}
/// <summary>
/// This will execute a DocumentDB query in the form of an IQueryable (Linq form) and return the results.
///
/// It handles paging, continuation tokens, and retriable errors such as "too many requests" for you,
/// while streaming query results out in chunks via IEnumerable / yield.
/// </summary>
/// <typeparam name="R"></typeparam>
/// <param name="queryable"></param>
/// <param name="queryExecutionHandler"></param>
/// <param name="enumerationExceptionHandler"></param>
/// <param name="feedResponseHandler"></param>
/// <param name="maxRetries"></param>
/// <param name="maxTime"></param>
/// <param name="shouldRetry"></param>
/// <returns></returns>
public static IEnumerable <R> StreamQueryWithContinuationAndRetry <R>(IQueryable <R> queryable, QueryExecutionHandler queryExecutionHandler, EnumerationExceptionHandler enumerationExceptionHandler, FeedResponseHandler feedResponseHandler, int maxRetries, TimeSpan maxTime, ShouldRetry shouldRetry)
{
IDocumentQuery <R> query = null;
try
{
query = queryable.AsDocumentQuery();
}
catch (Exception e)
{
throw new ArgumentException(BadQueryableMessage, e);
}
var context = new FeedResponseContext();
queryExecutionHandler(context, query.ToString());
feedResponseHandler(context, FeedResponseType.BeforeEnumeration, null);
while (query.HasMoreResults)
{
Task <FeedResponse <R> > t;
try
{
t = Task.Run(async() => await ExecuteResultWithRetry(() =>
query.ExecuteNextAsync <R>(),
null,
maxRetries,
maxTime,
shouldRetry));
t.Wait();
}
catch (Exception ex)
{
// note: if an IQueryable is returned to OData, throwing an exception here will cause it to take down w3wp.exe
bool handled = enumerationExceptionHandler(context, ex);
if (!handled)
{
feedResponseHandler(context, FeedResponseType.EnumerationAborted, null);
throw;
}
else
{
break;
}
}
var intermediateResponse = t.Result;
// lots of interesting info in intermediateResults such as RU usage, etc.
List <R> intermediateResults = intermediateResponse.ToList();
UpdateContext <R>(context, intermediateResponse, JsonConvert.SerializeObject(intermediateResults).Length, query.HasMoreResults);
feedResponseHandler(context, FeedResponseType.PageReceived, new FeedResponseWrapper <R>(intermediateResponse));
foreach (var result in intermediateResults)
{
yield return(result);
}
}
feedResponseHandler(context, FeedResponseType.AfterEnumeration, null);
}
