使用CosmosDB文档输出创建HttpTrigger Azure函数时出错

Question

我想创建一个Azure函数，它接受传递给它的JSON主体，并将该文档插入到Azure COSMOSDB实例中。

并按如下方式实现该函数：

#r "Newtonsoft.Json"
using Newtonsoft.Json.Linq;

using System.Net;

public static async Task<HttpResponseMessage> Run(HttpRequestMessage req, TraceWriter log, object outputDocument)
{
    var requestContent = await req.Content.ReadAsStringAsync();
    log.Verbose($@"Received request:\n{requestContent}");

    var newDoc = JObject.Parse(requestContent);
    newDoc["Id"] = Guid.NewGuid().ToString();
    newDoc["shardKey"] = newDoc.Value<string>(@"Id").Substring(8);

    outputDocument = newDoc;

    return req.CreateResponse(System.Net.HttpStatusCode.Created);
}

在门户中，我放入了一个简单的示例文档：

{
  "prop1": 2,
  "prop2": "2017-02-20",
}

{
  "id": "145ee924-f824-4064-8364-f96dc12ab138",
  "requestId": "5a27c287-2c91-40f5-be52-6a79c7c86bc2",
  "statusCode": 500,
  "errorCode": 0,
  "message": "'UploadDocumentToCosmos' can't be invoked from Azure WebJobs SDK. Is it missing Azure WebJobs SDK attributes?"
}

Answer 1

对于异步函数，您应该使用IAsyncCollector:

public static async Task<HttpResponseMessage> Run(
    HttpRequestMessage req, TraceWriter log, 
    IAsyncCollector<object> outputDocuments)
{
    ...
    await outputDocuments.AddAsync(newDoc);
}