Async and Await didn't work on web api - asp.net-web-api

Question

I am trying to use await on my async method but it didn't work. I input 2 array of parameters when calling the post method, only the last one is inserted
to database(I use Elasticsearch as database so when the _id is the same the document will replaced by the new one). and I found out when insert is not done yet the program is already run to query the database and the result is 0 so it's insert again instead of update.
I already add await on my program but it didn't work out. Can anyone help me with this problem? Thanks
here is my code
// POST api/values
[HttpPost]
public async Task<AvatarModel.AvatarResponse> Post(MultiLanguageTemp[] LangTemp)
{
//process param to multilanguage model
AvatarModel.AvatarResponse Resp = new AvatarModel.AvatarResponse();
try
{
for (int i = 0; i < LangTemp.Length; i++)
{
string Type = LangTemp[i].Type;
if ("ErrorCode".Equals(Type))
{
}
else
{
string GetLabelId = LangTemp[i].LabelId;
string GetTranslation = LangTemp[i].Translation;
MultiLanguage Lang = new MultiLanguage();
Lang.Type = LangTemp[i].Type;
Lang.Site = LangTemp[i].Site;
Lang.Language = LangTemp[i].LangId;
Lang.Source = LangTemp[i].Source;
Lang.TranslationList = new Dictionary<string, string>();
Lang.TranslationList.Clear();
Lang.TranslationList.Add(GetLabelId, GetTranslation);
//search elasticsearch first using id TYPE+SITE+LANG_ID+SOURCE
string ESResponse = await GetMultiLangAsync(Lang);
JObject GetResp = JObject.Parse(ESResponse);
//get elasticsearch Hits count
JToken GetHitsTotal = GetResp.SelectToken("hits.total");
int Hits = int.Parse(GetHitsTotal.ToString());
// if id exist then do update else do insert
if (Hits > 0)
{
string ResponseUpdate = await UpdateMultiLangAsync(GetLabelId, GetTranslation,Lang);
if (!ResponseUpdate.ToString().ToUpper().Contains("ERROR"))
{
Resp.Result = "0000000";
Resp.Message = "Update MultiLanguage Info is Success";
}
else
{
Resp.Result = "9000003";
Resp.Message = "Update MultiLanguage Info into ES failed";
}
}
else
{
//tasks.Add(InsertMultiLangAsync(Lang));
//insert new document into elasticsearch
string InsertESResponse = await InsertMultiLangAsync(Lang);
if (!InsertESResponse.ToUpper().Contains("ERROR"))
{
Resp.Result = "0000000";
Resp.Message = "Insert MultiLanguage Info is Success";
}
else
{
Resp.Result = "9000003";
Resp.Message = "Insert MultiLanguage Info into ES failed";
}
}
}
}
}
catch (Exception E)
{
Resp.Result = "9000005";
Resp.Message = E.Message.ToString();
}
return Resp;
}
public async Task<string> GetMultiLangAsync(MultiLanguage Lang)
{
var Client = new HttpClient();
Client.BaseAddress = new Uri("http://localhost:9200/multilanguage/MultiLangInfo/");
Client.DefaultRequestHeaders.Accept.Add(new MediaTypeWithQualityHeaderValue("application/json"));
var Query = "{\"query\": {\"match\": {\"_id\":\"" + Lang.Type + Lang.Site + Lang.Language + Lang.Source + "\"}}}";
var StringContent = new StringContent(Query, Encoding.UTF8, "application/json");
var Response = Client.PostAsync("_search", StringContent).Result.Content.ReadAsStringAsync();
//JObject GetResp = JObject.Parse(Response.Result);
return await Response;
}
public async Task<string> InsertMultiLangAsync(MultiLanguage Lang)
{
var Client = new HttpClient();
Client.BaseAddress = new Uri("http://localhost:9200/multilanguage/");
Client.DefaultRequestHeaders.Accept.Add(new MediaTypeWithQualityHeaderValue("application/json"));
var JsonTextMultiLang = JsonConvert.SerializeObject(Lang, Formatting.None, new JsonSerializerSettings { NullValueHandling = NullValueHandling.Ignore });
var StringContent = new StringContent(JsonTextMultiLang, Encoding.UTF8, "application/json");
var ResponseInsert = Client.PostAsync("MultiLangInfo/" + Lang.Type + Lang.Site + Lang.Language + Lang.Source, StringContent).Result.Content.ReadAsStringAsync();
return await ResponseInsert;
}
public async Task<string> UpdateMultiLangAsync(string GetLabelId,string GetTranslation, MultiLanguage Lang)
{
var UpdateES = "{\"doc\":{\"TranslationList\":{\"" + GetLabelId + "\":\"" + GetTranslation + "\"}},\"detect_noop\":true}";
var Client = new HttpClient();
Client.BaseAddress = new Uri("http://localhost:9200/multilanguage/MultiLangInfo/" + Lang.Type + Lang.Site + Lang.Language + Lang.Source + "/");
Client.DefaultRequestHeaders.Accept.Add(new MediaTypeWithQualityHeaderValue("application/json"));
var StringContent = new StringContent(UpdateES, Encoding.UTF8, "application/json");
var ResponseUpdate = Client.PostAsync("_update", StringContent).Result.Content.ReadAsStringAsync();
return await ResponseUpdate;
}

Answer 1

Here is my insight.
Based on the details you provided, you have a long-running task that would eventually create/update a record in your database. Now, the problem you encounter is the second http request you send is not waiting for the first one to finish even though you are using async/await pattern. Well, this is not how it works. Regardless of what you do, whether you block the thread or not, there is thread pooling and distinct http calls will have their own thread. So using async/await would not affect that at all. For the most part, you're using async/await correctly. However, what you're trying to achieve is not done by async/await. You might want to try a messaging system to queue all the requests. In that case, you can't put clients on hold, You'd generate a request id and send it to them immediately and process the request asynchronously in time.