Develop Reference

How to split an HTTP Request Body in two parts?

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();
}

Error Creating Folder in Sharepoint using REST API C#

I can accomplish all other tasks with the rest API, like uploading and downloading files, navigating through the file directory. I just keep getting either 400 Bad Request or sometimes with some tries I'll get 500 Internal Server Error. Also, I can create the request on postman and its successful
this is what the request should look like the rest is me creating it in c#
POST https://{site_url}/_api/web/folders
Authorization: "Bearer " + accessToken
Accept: "application/json;odata=verbose"
Content-Type: "application/json"
Content-Length: {length of request body as integer}
X-RequestDigest: "{form_digest_value}"
{
"__metadata": {
"type": "SP.Folder"
},
"ServerRelativeUrl": "/document library relative url/folder name"
}
private async Task PostFolderSharePoint(string url, string serverRelativeUrl)
{
string accessToken = GetAccessToken().GetAwaiter().GetResult();
string jsoncontent = JsonConvert.SerializeObject("{\"__metadata\": {\"type\": \"SP.Folder\"},\"ServerRelativeUrl\": serverRelativeUrl}");
var content = new StringContent(jsoncontent, Encoding.UTF8, "application/json");
var FormDiGestValue = await GetFormDigestValue(accessToken);
_httpClient.DefaultRequestHeaders.Authorization = new AuthenticationHeaderValue("Bearer", accessToken);
_httpClient.DefaultRequestHeaders.Accept.Add(new MediaTypeWithQualityHeaderValue("application/json"));
var requestMessage = new HttpRequestMessage(HttpMethod.Post,url) { Content = content };
requestMessage.Headers.Add("X-RequestDigest", FormDiGestValue);
HttpResponseMessage response = await _httpClient.SendAsync(requestMessage).ConfigureAwait(false);
return response;
}

This is how I create a folder with the Sharepoint REST API:
public async Task<string> CreateFolder(string folderName, string relativeUrl)
{
try
{
var url = "https://your.sharepoint.com/sites/devsite/_api/web/folders";
var json = "{\"ServerRelativeUrl\": \"" + relativeUrl + "/" + folderName + "\"}";
var payload = new StringContent(json, Encoding.UTF8, "application/json");
HttpClient client = new HttpClient();
client.DefaultRequestHeaders.Add("accept", "application/json;odata=verbose");
client.DefaultRequestHeaders.Add("X-User-Agent", "spoc");
client.DefaultRequestHeaders.Add("Authorization", "Bearer " + accessToken);
var response = await client.PostAsync(url, payload);
return await response.Content.ReadAsStringAsync();
}
catch (WebException we)
{
throw new SomethingException(we);
}
}
and to use it:
var modFolder = await spocRest.CreateFolder("MOD1", "Shared Documents");

How to implement oauth2 of Twitter on UWP?

I want to develop a small twitter application on UWP .
GET oauth/authenticate
GET oauth/authorize
POST oauth/access_token
POST oauth/request_token
POST oauth2/invalidate_token
POST oauth2/token
It is more information. I'm confused. So I want to login to Twitter by ComsumerKey, ComsumerKeySecret, Callback Uri. and get access_token to access data from api.twitter.com.
I think that I've to use POST oauth2/token before(Is it wrong?).
<!-- begin snippet: C# hide: false console: true babel: false -->
<!-- language: lang-html -->
public async Task<string> GetAccessTokenBYAuthorizeTwitter()
{
//throw new NotImplementedException();
var client = new HttpClient();
string postData = "grant_type=client_credentials";
var request = await client.PostAsync(ResourceUrl,new StringContent(postData));
//request headers
client.DefaultRequestHeaders.Add("Authorization", string.Format("Basic {0}", Convert.ToBase64String(Encoding.UTF8.GetBytes(ComsumerKeyAndSecret))));
client.DefaultRequestHeaders.Accept.Add(new System.Net.Http.Headers.MediaTypeWithQualityHeaderValue("application/json"));
return await request.Content.ReadAsStringAsync();
}
<!-- end snippet -->
Example : I try to login by Vimeo and successful.
public async Task<string> AuthorizeWithVimeo()
{
var clientId = "b8e1bff5d5d1f2c90f61017b135960adb42f5fe2";
var SpotifyUrl = "https://api.vimeo.com/oauth/authorize?client_id=" + Uri.EscapeDataString(clientId) + "&response_type=code&redirect_uri=" + Uri.EscapeDataString("https://example/callback") + "&state=xyzbc";
var StartUri = new Uri(SpotifyUrl);
var EndUri = new Uri("https://example/callback");
WebAuthenticationResult WebAuthenticationResult = await WebAuthenticationBroker.AuthenticateAsync(WebAuthenticationOptions.None, StartUri, EndUri);
if (WebAuthenticationResult.ResponseStatus == WebAuthenticationStatus.Success)
{
var responseData = WebAuthenticationResult.ResponseData;
//await GetSpotifyUserNameAsync(WebAuthenticationResult.ResponseData.ToString());
return responseData;
}
else if (WebAuthenticationResult.ResponseStatus == WebAuthenticationStatus.ErrorHttp)
{
return $"HTTP Error returned by AuthenticateAsync() : {WebAuthenticationResult.ResponseErrorDetail.ToString()}";
}
else
{
return $"Error returned by AuthenticateAsync() : {WebAuthenticationResult.ResponseStatus.ToString()}";
}
}

This should work
var client = new HttpClient();
client.DefaultRequestHeaders.Authorization = new AuthenticationHeaderValue(
"Basic",
Convert.ToBase64String(
Encoding.ASCII.GetBytes(
string.Format("{0}:{1}", Uri.EscapeDataString(oauth_consumer_key),
Uri.EscapeDataString(oauth_consumer_secret)))));
client.DefaultRequestHeaders.TryAddWithoutValidation("Accept-Encoding", "gzip");
client.DefaultRequestHeaders.TryAddWithoutValidation("Host", "api.twitter.com");
var content = new StringContent(postBody);
content.Headers.ContentType = new MediaTypeHeaderValue("application/x-www-form-urlencoded");
HttpResponseMessage response =await client.PostAsync(oauth_url, content);
response.EnsureSuccessStatusCode();
using (var responseStream = response.Content.ReadAsStreamAsync())
using (var decompressedStream = new GZipStream(responseStream.Result, CompressionMode.Decompress))
using (var streamReader = new StreamReader(decompressedStream))
{
var rawJWt = streamReader.ReadToEnd();
var jwt = JsonConvert.DeserializeObject(rawJWt);
}
More info

How to send MultipartForm using POST method in (Windows Phone 8.1) C#

Can any one explain how can i make POST request to a URL on web with different type of data, in my case i have an image and two string type values to send to a server in PHP.
here what i already have done
var stream = await file.OpenStreamForReadAsync();
var streamcontent = new StreamContent(stream);
streamcontent.Headers.ContentDisposition = new ContentDispositionHeaderValue("form-data")
{
Name = "photo",
FileName = file.Name
};
streamcontent.Headers.ContentType = new MediaTypeHeaderValue("image/jpeg");
MultipartFormDataContent multipart = new MultipartFormDataContent();
multipart.Add(streamcontent);
try
{
descContent = mytextbox.Text;
var stringcontent = new StringContent(descContent);
stringcontent.Headers.ContentType.Parameters.Add(new NameValueHeaderValue("description", descContent));
multipart.Add(stringcontent);
HttpResponseMessage res = await client.PostAsync(new Uri("http://localhost/web/test/index.php"), multipart);
res.EnsureSuccessStatusCode();
mytextbox.Text = await res.Content.ReadAsStringAsync();
}
catch (HttpRequestException ex)
{
mytextbox.Text = ex.Message;
}
this code will send the image file but not the description(string), i have searched over the internet but I could not find appropriate answer.
here is the PHP code
if (isset($_FILES['photo']))
{
echo $_FILES["photo"]["name"] . "<br>";
}
else
{
echo "Image: Error<br>";
}
if (isset($_POST['description']))
{
echo $_POST['description'];
}
else
{
echo "Text: Error";
}
any response will be highly appreciated.
thank you

I have search a lot and finally got the way out. here is the code
HttpClient client = new HttpClient();
client.BaseAddress = new Uri("http://www.yourdomain.com");
MultipartFormDataContent form = new MultipartFormDataContent();
HttpContent content = new StringContent("your string type data you want to post");
form.Add(content, "name");
var stream = await file.OpenStreamForReadAsync();
content = new StreamContent(stream);
content.Headers.ContentDisposition = new ContentDispositionHeaderValue("form-data")
{
Name = "image",
FileName = file.Name
};
form.Add(content);
var response = await client.PostAsync("index.php", form);
mytextblock.Text = response.Content.ReadAsStringAsync();
I wrote it on my blog here is the code. :-)
HappyCoding

Upload files with HTTPWebrequest (multipart/form-data)
http://www.paraesthesia.com/archive/2009/12/16/posting-multipartform-data-using-.net-webrequest.aspx/

HttpClient Post photo WITH message to Facebook Graph

Issue
I am trying to upload a photo to the Facebook API WITH a message.
Code Snippet - Upload
requestUri = "https://graph.facebook.com/v2.0/me/photos?access_token=MyAccessToken"
var streamContent = new StreamContent(fileStream);
streamContent.Headers.ContentDisposition = new ContentDispositionHeaderValue("form-data")
{
Name = "\"files\"",
FileName = "\"image.jpg\""
};
streamContent.Headers.ContentType = new MediaTypeHeaderValue("image/jpeg");
var messageContent = new StringContent("message=HelloWorld");
var resultJson = webRequestClient.Post(requestUri, new MultipartFormDataContent()
{
messageContent,
streamContent,
});
Code - webRequestClient
public string Post(string uri, HttpContent postData)
{
return PostAsync(uri, postData).Result;
}
public async Task<string> PostAsync(string uri, HttpContent httpContent)
{
string resultStream;
using (var httpClient = new HttpClient())
{
var response = await httpClient.PostAsync(uri, httpContent);
response.EnsureSuccessStatusCode();
resultStream = await response.Content.ReadAsStringAsync();
}
return resultStream;
}
Notes
If I remove the "messageContent" : It uploads he picture
If I use MultipartContent : It uploads the picture but ignores my "message"
Don't bother for now why I don't do use the async functionality
When it fails I get "bad" requests
When I append the "message=helloworld" in the requestUri, it works, but that isn't the most flexible solution for in my architecture to deal with this issue.

Check this it will solve you problem, either you have to send the image via stream then you don't need to tell that the type is "image/jpeg" explicitly.
protected async void TakePictureAndUpload()
{
var ui = new CameraCaptureUI();
var file = await ui.CaptureFileAsync(CameraCaptureUIMode.Photo);
if (file != null)
{
byte[] myPicArray = await GetPhotoBytesAsync(file);
HttpClient httpClient = new HttpClient();
httpClient.BaseAddress = new Uri("http://yourdomainname.com");
MultipartFormDataContent form = new MultipartFormDataContent();
HttpContent content = new ByteArrayContent(myPicArray);
form.Add(content, "media", "filename.jpg");
content = new StringContent("my-username");
form.Add(content, "username");
HttpResponseMessage response = await httpClient.PostAsync("directory/my-site.php", form);
}
}
public async Task<byte[]> GetPhotoBytesAsync(StorageFile file)
{
IRandomAccessStream fileStream = await file.OpenAsync(FileAccessMode.Read);
var reader = new Windows.Storage.Streams.DataReader(fileStream.GetInputStreamAt(0));
await reader.LoadAsync((uint)fileStream.Size);
byte[] pixels = new byte[fileStream.Size];
reader.ReadBytes(pixels);
return pixels;
}