internal async Task <IReadOnlyCollection <PartitionKeyRange> > GetPartitionKeyRanges(IDocumentClient client)
{
string responseContinuation = null;
var partitionKeyRanges = new List <PartitionKeyRange>();
var documentCollectionUri = UriFactory.CreateDocumentCollectionUri(this.Database, this.Collection);
do
{
var response = await client.ReadPartitionKeyRangeFeedAsync(documentCollectionUri, new FeedOptions { RequestContinuation = responseContinuation });
partitionKeyRanges.AddRange(response);
responseContinuation = response.ResponseContinuation;
}while (responseContinuation != null);
return(partitionKeyRanges);
}
public static async Task <IActionResult> PagedQuery(
[HttpTrigger(AuthorizationLevel.Function, "get", Route = "{database}/{collection}")] HttpRequest req,
string database,
string collection,
[CosmosDB("{database}", "{collection}", ConnectionStringSetting = "CosmosDBConnection")] IDocumentClient client,
ILogger log,
ExecutionContext context)
{
var functionName = context.FunctionName;
var queryString = req.GetQueryParameterDictionary();
var headers = req.GetTypedHeaders();
var pageSize = int.Parse(queryString.ContainsKey("pageSize") ? queryString["pageSize"] : DefaultPageSize.ToString());
var continuation = queryString.ContainsKey("continuation") ? queryString["continuation"] : null;
var results = new List <dynamic>();
var cosmosQuery = JObject.Parse(queryString["q"]);
var querySpec = new SqlQuerySpec(cosmosQuery["QueryText"]?.ToString(), JsonConvert.DeserializeObject <SqlParameterCollection>(cosmosQuery["Parameters"]?.ToString()));
try
{
Uri collectionUri = UriFactory.CreateDocumentCollectionUri(database, collection);
if (string.IsNullOrEmpty(querySpec.QueryText))
{
throw new ArgumentNullException("Please provide a query!");
}
var response = new PagedResults();
// Loop through partition key ranges
foreach (var pkRange in await client.ReadPartitionKeyRangeFeedAsync(collectionUri))
{
try
{
var options = new FeedOptions()
{
PartitionKeyRangeId = pkRange.Id,
RequestContinuation = continuation,
MaxItemCount = pageSize - results.Count,
ResponseContinuationTokenLimitInKb = ResponseContinuationTokenLimit,
EnableCrossPartitionQuery = EnableCrossPartitionQuery
};
using (var query = client
.CreateDocumentQuery <dynamic>(collectionUri, querySpec, options)
.AsDocumentQuery())
{
while (query.HasMoreResults && results.Count < pageSize)
{
// Get results
FeedResponse <dynamic> recordSet = await query.ExecuteNextAsync();
foreach (var record in recordSet)
{
results.Add(record);
}
// Create Response Object
response.Pagination.ContinuationToken = recordSet.ResponseContinuation;
// Set Links
var referrer = headers.Referer ?? new Uri(req.GetEncodedUrl());
response.Links.Self = referrer.OriginalString;
NameValueCollection qc = HttpUtility.ParseQueryString(referrer.Query, Encoding.UTF8);
qc.Remove("continuation");
if (!string.IsNullOrEmpty(recordSet.ResponseContinuation))
{
qc.Add("continuation", recordSet.ResponseContinuation);
response.Links.Next = $"{req.Scheme}://{req.Host}{req.Path}?{string.Join("&", qc.AllKeys.Select(k => string.Format("{0}={1}", k, Uri.EscapeDataString(qc[k]))))}";
}
else
{
response.Links.Next = null;
}
}
}
}
catch (Exception e)
{
if (e.Message.Contains("Microsoft.Azure.Documents.Query.CompositeContinuationToken"))
{
log.LogDebug("Skipping partition key range.");
}
else
{
throw;
}
}
}
response.Data = results;
return(new OkObjectResult(response));
}
catch (Exception e)
{
log.LogError($"{functionName} failed", e);
var response = new
{
e.Message,
};
return(new BadRequestObjectResult(response));
}
}