I'm fairly new to use HTTPClient and sending REST requests to APIs, I'm currently practicing multipart upload using this Google Drive API endpoint:
POST https://www.googleapis.com/upload/drive/v3/files?uploadType=multipart
There's an instruction that states there to split the request body into two parts, I tried to recreate this but was unable to do so.
https://developers.google.com/drive/api/guides/manage-uploads#multipart
Here's my current code:
async void UploadFile(StorageFile fileName)
{
using (HttpClient client = new HttpClient())
{
// Opens files and convert it to stream
var resultStream = await fileName.OpenReadAsync();
var fileStreamContent = new StreamContent(resultStream.AsStream());
// Create file MetaData
var fileMetaData = JsonConvert.SerializeObject(
new { name = fileName.Name, mimetype = fileName.ContentType });
// Create POST request
var requestMessage = new HttpRequestMessage(HttpMethod.Post, uploadFileEndpoint);
requestMessage.Headers.Authorization = new AuthenticationHeaderValue(tokenType, accessToken);
// Add request body
requestMessage.Content = new StringContent(fileMetaData, Encoding.UTF8, "application/json");
requestMessage.Content.Headers.ContentType = new MediaTypeHeaderValue("multipart/related");
var response = await client.SendAsync(requestMessage);
string responseString = await response.Content.ReadAsStringAsync();
output(responseString);
}
}
Any help would be greatly appreciated, thank you!
According to the documentation on Perform a multipart upload (HTTP tab), you need the MultipartFormDataContent as suggested by #Jeremy.
There are a few things needed to perform/migrate:
Add AuthenticationHeaderValue into client.DefaultRequestHeaders.Authorization.
Create a StreamContent instance, fileStreamContent (which you have done) and specify its Headers.ContentType.
Create a StringContent instance, stringContent (which you have done).
Append both StreamContent and StringContent into the MultipartFormDataContent instance, formData.
Specify the formData's Headers.ContentType as requested in API docs.
Post the formData with await client.PostAsync(/* API Url */, formData);
using (HttpClient client = new HttpClient())
{
client.DefaultRequestHeaders.Authorization = new AuthenticationHeaderValue(tokenType, accessToken);
// Opens files and convert it to stream
var resultStream = await fileName.OpenReadAsync();
var fileStreamContent = new StreamContent(resultStream.AsStream());
fileStreamContent.Headers.ContentType = new MediaTypeHeaderValue(fileName.ContentType);
// Create file MetaData
var fileMetaData = JsonConvert.SerializeObject(new { name = fileName.Name, mimetype = fileName.ContentType });
var stringContent = new StringContent(fileMetaData, Encoding.UTF8, "application/json");
// Create POST request
MultipartFormDataContent formData = new MultipartFormDataContent();
formData.Add(stringContent, "metadata");
formData.Add(fileStreamContent, "media");
formData.Headers.ContentType = new MediaTypeHeaderValue("multipart/related");
var response = await client.PostAsync(uploadFileEndpoint, formData);
string responseString = await response.Content.ReadAsStringAsync();
}
Related
I would like to ask if it is possible for a created ASP.NET Web API (written in C#) to post to an external API?
If it is possible, please share sample code that can post to an url with adding headers and receive a callback from the external API.
A simple way to make HTTP-Request out of a .NET-Application is the System.Net.Http.HttpClient (MSDN). An example usage would look something like this:
// Should be a static readonly field/property, wich is only instanciated once
var client = new HttpClient();
var requestData = new Dictionary<string, string>
{
{ "field1", "Some data of the field" },
{ "field2", "Even more data" }
};
var request = new HttpRequestMessage() {
RequestUri = new Uri("https://domain.top/route"),
Method = HttpMethod.Post,
Content = new FormUrlEncodedContent(requestData)
};
request.Headers // Add or modify headers
var response = await client.SendAsync(request);
// To read the response as string
var responseString = await response.Content.ReadAsStringAsync();
// To read the response as json
var responseJson = await response.Content.ReadAsAsync<ResponseObject>();
Essentially you need use an instance of HttpClient to send an HttpRequestMessage to an endpoint.
Here is an example to post some jsonData to someEndPointUrl:
var client = new HttpClient();
var request = new HttpRequestMessage(HttpMethod.Post, someEndPointUrl);
request.Headers.Accept.Clear();
request.Headers.Accept.Add(new MediaTypeWithQualityHeaderValue("application/json"));
request.Headers.Authorization = new AuthenticationHeaderValue("Bearer", token);
request.Content = new StringContent(jsonData, Encoding.UTF8, "application/json");
var response = await client.SendAsync(request, CancellationToken.None);
var str = await response.Content.ReadAsStringAsync();
if (response.StatusCode == HttpStatusCode.OK)
{
// handle your response
}
else
{
// or failed response ?
}
I am working on an angular and .NET Core application. I have to pass the file uploaded from angular to WEB API. My code is:
public async Task ImportDataScienceAnalytics(string authToken, IFormFile file)
{
var baseUrl = Import.GetBaseURL();
var client = new RestClientExtended(baseUrl + "algorithm/import");
var request = new RestRequest(Method.POST);
request.AddHeader("authorization", authToken);
string jsonBody = JsonConvert.SerializeObject(file);
request.AddJsonBody(jsonBody);
var response = await client.ExecutePostTaskAsync(request);
var result = response.Content;
}
Issue is that i get "No Attachment Found". I think the issue is because of IFormFile. How can i resolve this issue so that i can upload the file to web api.
It seems that you'd like to post uploaded file to an external API from your API action using RestClient, you can refer to the following code snippet.
var client = new RestClient(baseUrl + "algorithm/import");
var request = new RestRequest(Method.POST);
request.AddHeader("authorization", authToken);
using (var ms = new MemoryStream())
{
file.CopyTo(ms);
var fileBytes = ms.ToArray();
request.AddFile("file", fileBytes, file.FileName, "application/octet-stream");
}
//...
Testing code of Import action
public IActionResult Import(IFormFile file)
{
//...
//code logic here
You need to make following changes to the code.
var baseUrl = Import.GetBaseURL();
var client = new RestClientExtended(baseUrl + "algorithm/import");
var request = new RestRequest(Method.POST);
byte[] data;
using (var br = new BinaryReader(file.OpenReadStream()))
data = br.ReadBytes((int)file.OpenReadStream().Length);
ByteArrayContent bytes = new ByteArrayContent(data);
MultipartFormDataContent multiContent = new MultipartFormDataContent
{
{ bytes, "file", file.FileName }
};
//request.AddHeader("authorization", authToken);
//string jsonBody = JsonConvert.SerializeObject(file);
//request.AddJsonBody(jsonBody);
/// Pass the multiContent into below post
var response = await client.ExecutePostTaskAsync(request);
var result = response.Content;
Do not forget to pass the variable multiContent into the post call.
I need to recreate this request I made in Postman with C#, I found that the HttpClient class solves most of my problems, but this time I couldn't solve it on my own.
I embbeded an image with an example of the very post request.
POST REQUEST IN POSTMAN
There are three text paramethers and one file I need to send, with a content-type of form-data, the file needs to be a .json.
I tried constructing the POST request in many ways; this is my last version:
string endpoint = $"{Endpoint}/captcha";
string token_paramsJSON = JsonConvert.SerializeObject(v3Request.token_params);
Hashtable ParametrosPOSTCaptcha = GetV3POSTParams(v3Request);
UnicodeEncoding uniEncoding = new UnicodeEncoding();
using (Stream ms = new MemoryStream()) {
var sw = new StreamWriter(ms, uniEncoding);
sw.Write(token_paramsJSON);
sw.Flush();
ms.Seek(0, SeekOrigin.Begin);
using (MultipartFormDataContent form = new MultipartFormDataContent())
{
form.Add(new StringContent(v3Request.username), "username");
form.Add(new StringContent(v3Request.password), "password");
form.Add(new StringContent(v3Request.type.ToString()), "type");
form.Add(new StreamContent(ms));
var response = await _httpClient.PostAsync(endpoint, form);
string ResponseTest = await GetResponseText(response);
}
}
With this code, I successfully establish a connection with the endpoint, send the username and password.
But the response differs from the one I get with Postman using the same paramethers:
Postman: x=0&xx=1892036372&xxx=&xxxxx=1
The actual response I get is this:
HttpClient: {"error": "not-logged-in"}
Thanks in advance!
Finally, I could solve it using the following implementation:
string endpoint = $"{Endpoint}/endpointName";
string token_paramsJSON = JsonConvert.SerializeObject(v3Request.token_params, Formatting.Indented);
Dictionary<string,string> PostParams = GetPOSTParams(v3Request);
HttpRequestMessage request = new HttpRequestMessage(HttpMethod.Post, endpoint);
UnicodeEncoding uniEncoding = new UnicodeEncoding();
using (MultipartFormDataContent form = new MultipartFormDataContent())
{
foreach(var field in PostParams)
{
StringContent content = new StringContent(field.Value);
content.Headers.ContentType = null;
form.Add(content, field.Key);
}
var JsonFile = new StringContent(token_paramsJSON);
JsonFile.Headers.ContentType = new MediaTypeHeaderValue("application/json");
JsonFile.Headers.ContentDisposition = new ContentDispositionHeaderValue("form-data")
{
Name = "\"token_params\"",
FileName = "\"token.json\""
};
form.Add(JsonFile);
request.Content = form;
var response = await _httpClient.SendAsync(request, CancellationToken.None);
return await GetCaptchaFromResponse(response);
}
When I use HttpClient class to send a POST request to an API URL, it modifies the URL that I've passed to it. For example, when I use the main API URL the RequestUri is incorrect and I receive the not found response. This problem happens when I use api word in the URL !!
Concept:
The Incorrect, modified URL:
Url: https://sandbox-api.alopeyk.com/api/v2/order
Request Url: https://sandbox-api.alopeyk.com
The Correct, and expected URL (This is the one I specify)
Url: https://google.com/api/v2/order
Request Url: https://google.com/api/v2/order
Code:
public async Task<CreateOrderResponse> CreateOrderAsync(CreateOrderRequest request)
{
var endPoint = EndPointFactory<CreateOrderResponse>.Build(HttpMethod.Post);
var jsonString = JsonConvert.SerializeObject(request);
var url = new Uri("https://sandbox-api.alopeyk.com");
var encodedFrom = new StringContent(jsonString);
var httpClient = endPoint.GetHttpClient(url);
var httpResponse = await httpClient.PostAsync("api/v2/orders", encodedFrom).ConfigureAwait(false);
// when use api it's https://sandbox-api.alopeyk.com it should be https://sandbox-api.alopeyk.com/api/v2/orders
// when use other host name for example it's correct
var requesturl = httpResponse.RequestMessage.RequestUri;
return await httpResponse.Content.ReadAsAsync<CreateOrderResponse>().ConfigureAwait(false);
}
// in the EndPoint class
public HttpClient GetHttpClient(Uri url)
{
return new Http.HttpClientFactory().GetOrCreate(Url, Headers);
}
If you want to see HttpClientFactory it's here.
The HttpClient have a problem with my main hostname that it's https://sandbox-api.alopeyk.com
Your Uri must end with a slash like this:
var url = new Uri("https://sandbox-api.alopeyk.com/");
That's a rather silly restriction of HttpClient.
Try this code:
HttpClient client = new HttpClient();
client.BaseAddress = new Uri("https://sandbox-api.alopeyk.com");
HttpResponseMessage response = client.PostAsync("api/v2/orders", new StringContent(jsonString, Encoding.UTF8, "text/json")).Result;
if (response.IsSuccessStatusCode)
{
// Parse the response body. Blocking!
var responseData = response.Content.ReadAsStringAsync().Result;
}
You can try with this code
HttpResponseMessage response = null;
using (var client = new HttpClient())
{
using (var request = new HttpRequestMessage(HttpMethod.Post,"https://sandbox-api.alopeyk.com/api/v2/orders"))
{
request.Headers.Accept.Add(new MediaTypeWithQualityHeaderValue("application/json"));
request.Headers.Authorization = new AuthenticationHeaderValue("Bearer", /*token herer*/);
var data = new StringContent(JsonConvert.SerializeObject(request, Encoding.UTF8, "application/json"));
request.Content = data;
response = await client.SendAsync(request);
}
}
I am trying to use the Trustpilot API, to post invitations to review products.
I have successfully gone through the authentication step as you can see in the code below, however I am unable to successfully post data to the Trustpilot Invitations API. The PostAsnyc method appears to be stuck with an WaitingForActivation status. I wonder if there is anything you can suggest to help.
Here is my code for this (the API credentials here aren't genuine!):
using (HttpClient httpClient = new HttpClient())
{
string trustPilotAccessTokenUrl = "https://api.trustpilot.com/v1/oauth/oauth-business-users-for-applications/accesstoken";
httpClient.BaseAddress = new Uri(trustPilotAccessTokenUrl);
httpClient.DefaultRequestHeaders.Accept.Add(new MediaTypeWithQualityHeaderValue("application/x-www-form-urlencoded"));
var authString = "MyApiKey:MyApiSecret";
httpClient.DefaultRequestHeaders.Authorization = new System.Net.Http.Headers.AuthenticationHeaderValue("Basic", Base64Encode(authString));
var stringPayload = "grant_type=password&username=MyUserEmail&password=MyPassword";
var httpContent = new StringContent(stringPayload, Encoding.UTF8, "application/x-www-form-urlencoded");
HttpResponseMessage httpResponseMessage = httpClient.PostAsync(trustPilotAccessTokenUrl, httpContent).Result;
var accessTokenResponseString = httpResponseMessage.Content.ReadAsStringAsync().Result;
var accessTokenResponseObject = JsonConvert.DeserializeObject<AccessTokenResponse>(accessTokenResponseString);
// Create invitation object
var invitation = new ReviewInvitation
{
ReferenceID = "inv001",
RecipientName = "Jon Doe",
RecipientEmail = "Jon.Doe#comp.com",
Locale = "en-US"
};
var jsonInvitation = JsonConvert.SerializeObject(invitation);
var client = new HttpClient();
client.DefaultRequestHeaders.Add("token", accessTokenResponseObject.AccessToken);
var invitationsUri = new Uri("https://invitations-api.trustpilot.com/v1/private/business-units/{MyBusinessID}/invitations");
// This here as a status of WaitingForActivation!
var a = client.PostAsync(invitationsUri, new StringContent(jsonInvitation)).ContinueWith((postTask) => postTask.Result.EnsureSuccessStatusCode());
}
This is how I solved the issue:
// Serialize our concrete class into a JSON String
var jsonInvitation = JsonConvert.SerializeObject(invitationObject);
// Wrap our JSON inside a StringContent which then can be used by the HttpClient class
var stringContent = new StringContent(jsonInvitation);
// Get the access token
var token = GetAccessToken().AccessToken;
// Create a Uri
var postUri = new Uri("https://invitations-api.trustpilot.com/v1/private/business-units/{BusinessUnitID}/invitations");
// Set up the request
HttpRequestMessage request = new HttpRequestMessage(HttpMethod.Post, postUri);
request.Content = stringContent;
request.Content.Headers.ContentType = new MediaTypeHeaderValue("application/json");
request.Content.Headers.Add("token", token);
// Set up the HttpClient
var httpClient = new HttpClient();
//httpClient.DefaultRequestHeaders.Accept.Clear();
//httpClient.BaseAddress = postUri;
//httpClient.DefaultRequestHeaders.Authorization = new AuthenticationHeaderValue("Bearer", token);
//httpClient.DefaultRequestHeaders.AcceptLanguage.Add(new StringWithQualityHeaderValue("en-US"));
var task = httpClient.SendAsync(request);
task.Wait();
This question here on SO was helpful:
How do you set the Content-Type header for an HttpClient request?