C# reading OData $batch multipart/mixed response to a meaningful object(s) - odata

Question

I am consuming an OData Service, I am successfully POSTing my request (using RestSharp) to /$batch endpoint and getting the response. the response header contains
"Content-Type" : "multipart/mixed; boundary=<GUID>"
Body is
--C4254E82B51CFE5BD04201606B9AB7C50
Content-Type: multipart/mixed; boundary=C4254E82B51CFE5BD04201606B9AB7C51
Content-Length: 2221
--C4254E82B51CFE5BD04201606B9AB7C51
Content-Type: application/http; charset=utf-8
Content-Length: 2037
content-transfer-encoding: binary
HTTP/1.1 201 Created
Content-Type: application/json
Content-Length: 1732
location: https://test.api/Event/CarEntries('4003581738')
dataserviceversion: 2.0
etag: W/"datetimeoffset'2021-04-21T00%3A49%3A45Z'"
{ JSON }
--C4254E82B51CFE5BD04201606B9AB7C51--
--C4254E82B51CFE5BD04201606B9AB7C50
Content-Type: application/http; charset=utf-8
Content-Length: 15116
content-transfer-encoding: binary
HTTP/1.1 200 OK
Content-Type: application/json
Content-Length: 15017
dataserviceversion: 2.0
{ JSON }
--C4254E82B51CFE5BD04201606B9AB7C50--
How do I deserialise and extract the JSON Objects in my C# code? I do not want to invent a Regex pattern (well that is my last resort)
I did try using "Simple.OData.Client" (also a few others) but my request is not 100% compatible with the "Simple.OData.Client".
Also tried extracting using the below code but not necessary give me what I want
var sc = new StringContent(response.Content);
var content = sc.ReadAsStreamAsync().Result;
var streamContent = new StreamContent(content);
streamContent.Headers.ContentType = MediaTypeHeaderValue.Parse(response.ContentType);
var provider = streamContent.ReadAsMultipartAsync().Result;
Can someone giveme the best way to extract the Json objects ?
Thanks
Nero

Answer 1

I manage to get this working HttpClient and System.Net.Http.Formatting.Extension
Below is the code
using (var httpClient = new HttpClient())
{
using (var request = new HttpRequestMessage(new HttpMethod("POST"), "https://service-url/Entity/v1.3/$batch"))
{
request.Headers.TryAddWithoutValidation("Accept", "application/json");
request.Headers.TryAddWithoutValidation("Client-Id", "XXXXXXXXX");
// Add all the headers here
// this is your custom batch request
request.Content = new StringContent("--batch\ncontent-type: multipart/mixed;boundary=changeset\n\n--changeset\ncontent-type: application/http\nContent-Transfer-Encoding: binary\n\nPOST CarEntries HTTP/1.1\ncontent-type: application/json;charset=utf-8\naccept: application/json;\n\n{\n\"RefId\": \"Test\",\n\"Child\": {\n\"ChildId\": \"412000415\"\n}\n}\n--changeset--\n--batch--");
request.Content.Headers.ContentType = MediaTypeHeaderValue.Parse("multipart/mixed;boundary=batch"); // This is imporatnt - but please refer to your api documentation
var response = await httpClient.SendAsync(request);
response.EnsureSuccessStatusCode();
var multiPartContent = await response.Content.ReadAsMultipartAsync(); // This is part of the extension
var mixedContent = multiPartContent.Contents.First(); // you will have multiple contents, select the content you want
var data = await mixedContent.ReadAsStringAsync();// read it as string
Regex rg = new Regex(#"\{(.|\s)*\}"); // find the json object from mixed content
var json = rg.Match(data);
return JsonConvert.DeserializeObject<TMessage>(json.Value);
}
}
Hope this helps someone in the future. But still, my goal is to use "Simple.OData.Client" or "Microsoft.OData.Client"