I am using Web api controller as follows:
[HttpPost]
public HttpResponseMessage PostMethod(string filename)
{
Stream downloadStream = BL.method(fileName);
HttpResponseMessage response = new HttpResponseMessage();
response.content= new StreamContent(downloadStream);
return response;
}
When I try to call the above method using fiddler I am getting an exception saying
'downloadStream.ReadTimeout' threw an exception of type
'System.InvalidOperationException'.
Can the stream be set in response and sent? Is there any modification for the above code?
There seems to be a problem with your stream. Without knowing how stream is generated it is difficult to say. If you replace BL.method(fileName); with just loading the file yourself using FileStream this should work (I just tested it myself).
On the side note, there are a few problems with your approach:
You use POST. Since you are not changing anything GET is better.
You are not setting ContentType header so client can have problem using resource
You are not disposing the stream so this stream could stay in limbo and generally not good.
Try using the PushStreamContent, maybe by not buffering the file in memory, you might avoid your timeout.
[HttpPost]
public HttpResponseMessage PostMethod(string filename)
{
Stream downloadStream = BL.method(fileName);
HttpResponseMessage response = new HttpResponseMessage();
response.Content = new PushStreamContent((responseStream, httpContent, tc) => {
downloadStream.CopyTo(responseStream);
responseStream.Close();
}, "application/octet-stream");
return response;
}
Related
I'm trying to drag and drop file upload with a progress bar.
I have a div which is listening to files being dropped on which is working perfectly.
I'm then..
//Setting up a XmlHttpRequest
xhr = new XMLHttpRequest();
//Open connection
xhr.open("post", "api/ImageUpload", true);
// Set appropriate headers
xhr.setRequestHeader("Content-Type", "multipart/form-data");
xhr.setRequestHeader("X-File-Type", uf.type);
xhr.setRequestHeader("X-File-Name", uf.name);
xhr.setRequestHeader("X-File-Size", uf.size);
This sends fine, with the stream as the body of the request to the Web API (not async).
[System.Web.Mvc.HttpPost]
public string Post()
{
Stream stream = HttpContext.Current.Request.InputStream;
String filename = HttpContext.Current.Request.Headers["X-File-Name"];
FileModel file = uploadService.UploadFile(stream, filename);
return file.Id.ToString();
}
I'm trying to chance the request to "public async Task< string> Post(){ }
If the method was using a multipart form on the page instead of XmlHttpRequest I would have used "await Request.Content.ReadAsMultipartAsync(provider)" but this doesn't seem to be populated at the time I need it.
So what is the correct was to handle and an Async call from XmlHttpRequest on a Web API in order to record progress during the request with XHR's progress event?
I have looked at a great deal of pages so far to find a solution but this is the page I have used primarily.
http://robertnyman.com/html5/fileapi-upload/fileapi-upload.html
Thanks for any help
Oliver
It looks like someone else had the same question with you and got an answer yet. please have a look at ASP.NET MVC 4 Web Api ajax file upload.
And here is an example from microsoft http://www.asp.net/web-api/overview/working-with-http/sending-html-form-data,-part-2.
I combined the two above solution together and worked for me (just adjust a little bit)
one line change in Javascritp
xhr.open("post", "api/upload", true);
Save the file using stream
public class UploadController : ApiController
{
public async Task<HttpResponseMessage> PostFormData()
{
string root = HttpContext.Current.Server.MapPath("~/App_Data");
var fileName = Path.Combine(root, Request.Headers.GetValues("X-File-Name").First());
try
{
var writer = new StreamWriter(fileName);
await Request.Content.CopyToAsync(writer.BaseStream);
writer.Close();
return Request.CreateResponse(HttpStatusCode.OK);
}
catch (System.Exception e)
{
return Request.CreateErrorResponse(HttpStatusCode.InternalServerError, e);
}
}
}
I get this error in my client (an ASP.NET MVC application) from a call to my ASP.NET Web API. I checked and the Web API is returning the data alright.
No MediaTypeFormatter is available to read an object of type
'IEnumerable`1' from content with media type 'text/plain'.
I believe that I can inherit from DataContractSerializer and implement my own serializer which can attach the Content-Type HTTP header as text/xml.
But my question is: is that necessary?
Because if it was, it would mean that the default DataContractSerializer does not set this essential header. I was wondering if Microsoft could leave such an important thing out. Is there another way out?
Here's the relevant client side code:
public ActionResult Index()
{
HttpClient client = new HttpClient();
var response = client.GetAsync("http://localhost:55333/api/bookreview/index").Result;
if (response.IsSuccessStatusCode)
{
IEnumerable<BookReview> reviews = response.Content.ReadAsAsync<IEnumerable<BookReview>>().Result;
return View(reviews);
}
else
{
ModelState.AddModelError("", string.Format("Reason: {0}", response.ReasonPhrase));
return View();
}
}
And here's the server side (Web API) code:
public class BookReviewController : ApiController
{
[HttpGet]
public IEnumerable<BookReview> Index()
{
try
{
using (var context = new BookReviewEntities())
{
context.ContextOptions.ProxyCreationEnabled = false;
return context.BookReviews.Include("Book.Author");
}
}
catch (Exception ex)
{
var responseMessage = new HttpResponseMessage
{
Content = new StringContent("Couldn't retrieve the list of book reviews."),
ReasonPhrase = ex.Message.Replace('\n', ' ')
};
throw new HttpResponseException(responseMessage);
}
}
}
I believe (because I don't have time to test it now) that you need to explicitly set the Status Code on the responseMessage you are passing to HttpResponseException. Normally, HttpResponseException will set the status code for you, but because you are providing a responsemessage explicitly, it will use the status code from that. By default, `HttpResponseMessage has a status code of 200.
So what is happening is you are getting an error on the server, but still returning a 200. Which is why your client is trying to deserialize the text/plain body produced by StringContent, as if it were an IEnumerable.
You need to set
responseMessage.StatusCode = HttpStatusCode.InternalServerError
in your exception handler on the server.
How about just using ReadAsStringAsync if your WebAPI is expecting to return content in plain text?
response.Content.ReadAsStringAsync().Result;
I have the following method that writes a stream in a HttpResponse object.
public HttpResponse ShowPDF(Stream stream)
{
MemoryStream memoryStream = (MemoryStream) stream;
httpResponse.Clear();
httpResponse.Buffer = true;
httpResponse.ContentType = "application/pdf";
httpResponse.BinaryWrite(memoryStream.ToArray());
httpResponse.End();
return httpResponse;
}
In order to test it, I need to recover the processed stream.
Is there someway to read the stream from the httpResponse object?
I have two ideas... one to mock the HttpResponse, and the other is to simulate a web server.
1. Mocking HttpResponse
I wrote this before I knew which mocking framework you used. Here's how you could test your method using TypeMock.
This assumes that you pass your httpResponse variable to the method, changing the method as follows:
public void ShowPDF(Stream stream, HttpResponse httpResponse)
Of course you would change this to passing it to a property on your Page object instead, if it is a member of your Page class.
And here's an example of how you could test using a fake HttpResponse:
internal void TestPDF()
{
FileStream fileStream = new FileStream("C:\\deleteme\\The Mischievous Nerd's Guide to World Domination.pdf", FileMode.Open);
MemoryStream memoryStream = new MemoryStream();
try
{
memoryStream.SetLength(fileStream.Length);
fileStream.Read(memoryStream.GetBuffer(), 0, (int)fileStream.Length);
memoryStream.Flush();
fileStream.Close();
byte[] buffer = null;
var fakeHttpResponse = Isolate.Fake.Instance<HttpResponse>(Members.ReturnRecursiveFakes);
Isolate.WhenCalled(() => fakeHttpResponse.BinaryWrite(null)).DoInstead((context) => { buffer = (byte[])context.Parameters[0]; });
ShowPDF(memoryStream, fakeHttpResponse);
if (buffer == null)
throw new Exception("It didn't write!");
}
finally
{
memoryStream.Close();
}
}
2. Simulate a Web Server
Perhaps you can do this by simulating a web server. It might sound crazy, but it doesn't look like it's that much code. Here are a couple of links about running Web Forms outside of IIS.
Can I run a ASPX and grep the result without making HTTP request?
http://msdn.microsoft.com/en-us/magazine/cc163879.aspx
I'm working on a web service using ASP.NET MVC's new WebAPI that will serve up binary files, mostly .cab and .exe files.
The following controller method seems to work, meaning that it returns a file, but it's setting the content type to application/json:
public HttpResponseMessage<Stream> Post(string version, string environment, string filetype)
{
var path = #"C:\Temp\test.exe";
var stream = new FileStream(path, FileMode.Open);
return new HttpResponseMessage<Stream>(stream, new MediaTypeHeaderValue("application/octet-stream"));
}
Is there a better way to do this?
Try using a simple HttpResponseMessage with its Content property set to a StreamContent:
// using System.IO;
// using System.Net.Http;
// using System.Net.Http.Headers;
public HttpResponseMessage Post(string version, string environment,
string filetype)
{
var path = #"C:\Temp\test.exe";
HttpResponseMessage result = new HttpResponseMessage(HttpStatusCode.OK);
var stream = new FileStream(path, FileMode.Open, FileAccess.Read);
result.Content = new StreamContent(stream);
result.Content.Headers.ContentType =
new MediaTypeHeaderValue("application/octet-stream");
return result;
}
A few things to note about the stream used:
You must not call stream.Dispose(), since Web API still needs to be able to access it when it processes the controller method's result to send data back to the client. Therefore, do not use a using (var stream = …) block. Web API will dispose the stream for you.
Make sure that the stream has its current position set to 0 (i.e. the beginning of the stream's data). In the above example, this is a given since you've only just opened the file. However, in other scenarios (such as when you first write some binary data to a MemoryStream), make sure to stream.Seek(0, SeekOrigin.Begin); or set stream.Position = 0;
With file streams, explicitly specifying FileAccess.Read permission can help prevent access rights issues on web servers; IIS application pool accounts are often given only read / list / execute access rights to the wwwroot.
For Web API 2, you can implement IHttpActionResult. Here's mine:
using System;
using System.IO;
using System.Net;
using System.Net.Http;
using System.Net.Http.Headers;
using System.Threading;
using System.Threading.Tasks;
using System.Web;
using System.Web.Http;
class FileResult : IHttpActionResult
{
private readonly string _filePath;
private readonly string _contentType;
public FileResult(string filePath, string contentType = null)
{
if (filePath == null) throw new ArgumentNullException("filePath");
_filePath = filePath;
_contentType = contentType;
}
public Task<HttpResponseMessage> ExecuteAsync(CancellationToken cancellationToken)
{
var response = new HttpResponseMessage(HttpStatusCode.OK)
{
Content = new StreamContent(File.OpenRead(_filePath))
};
var contentType = _contentType ?? MimeMapping.GetMimeMapping(Path.GetExtension(_filePath));
response.Content.Headers.ContentType = new MediaTypeHeaderValue(contentType);
return Task.FromResult(response);
}
}
Then something like this in your controller:
[Route("Images/{*imagePath}")]
public IHttpActionResult GetImage(string imagePath)
{
var serverPath = Path.Combine(_rootPath, imagePath);
var fileInfo = new FileInfo(serverPath);
return !fileInfo.Exists
? (IHttpActionResult) NotFound()
: new FileResult(fileInfo.FullName);
}
And here's one way you can tell IIS to ignore requests with an extension so that the request will make it to the controller:
<!-- web.config -->
<system.webServer>
<modules runAllManagedModulesForAllRequests="true"/>
For those using .NET Core:
You can make use of the IActionResult interface in an API controller method, like so.
[HttpGet("GetReportData/{year}")]
public async Task<IActionResult> GetReportData(int year)
{
// Render Excel document in memory and return as Byte[]
Byte[] file = await this._reportDao.RenderReportAsExcel(year);
return File(file, "application/vnd.openxmlformats", "fileName.xlsx");
}
This example is simplified, but should get the point across. In .NET Core this process is so much simpler than in previous versions of .NET - i.e. no setting response type, content, headers, etc.
Also, of course the MIME type for the file and the extension will depend on individual needs.
Reference: SO Post Answer by #NKosi
While the suggested solution works fine, there is another way to return a byte array from the controller, with response stream properly formatted :
In the request, set header "Accept: application/octet-stream".
Server-side, add a media type formatter to support this mime type.
Unfortunately, WebApi does not include any formatter for "application/octet-stream". There is an implementation here on GitHub: BinaryMediaTypeFormatter (there are minor adaptations to make it work for webapi 2, method signatures changed).
You can add this formatter into your global config :
HttpConfiguration config;
// ...
config.Formatters.Add(new BinaryMediaTypeFormatter(false));
WebApi should now use BinaryMediaTypeFormatter if the request specifies the correct Accept header.
I prefer this solution because an action controller returning byte[] is more comfortable to test. Though, the other solution allows you more control if you want to return another content-type than "application/octet-stream" (for example "image/gif").
For anyone having the problem of the API being called more than once while downloading a fairly large file using the method in the accepted answer, please set response buffering to true
System.Web.HttpContext.Current.Response.Buffer = true;
This makes sure that the entire binary content is buffered on the server side before it is sent to the client. Otherwise you will see multiple request being sent to the controller and if you do not handle it properly, the file will become corrupt.
The overload that you're using sets the enumeration of serialization formatters. You need to specify the content type explicitly like:
httpResponseMessage.Content.Headers.ContentType = new MediaTypeHeaderValue("application/octet-stream");
You could try
httpResponseMessage.Content.Headers.Add("Content-Type", "application/octet-stream");
You can try the following code snippet
httpResponseMessage.Content.Headers.Add("Content-Type", "application/octet-stream");
Hope it will work for you.
I am trying to implement restful protocol on jetty server. I have runnable server and i can access it from my rest client. My server side project is a maven project. I have a problem about the character encoding.When i check response, before send it from controller, there is no encoding problem. But after i return response to client, i see broken data. Response header is UTF-8. Also i have a listener for this problem and i am setting to request and response to UTF-8. I guess problem happens when i try to write my response data to response.
#GET
#Path("/")
#Produces({"application/xml;charset=UTF-8","application/json;charset=UTF-8"})
public String getPersons(#Context HttpServletRequest request, #Context HttpServletResponse response) {
List<Person> persons = personService.getPersons(testUserId, collectionOption, null);
if (persons == null) {
persons = new ArrayList<Person>();
}
String result = JsonUtil.listToJson(persons);
//result doesnt has any encoding problem at this line
response.setContentType("application/json");
response.setContentLength(result.length());
response.setCharacterEncoding("utf-8");
//i guess problem happen after this line
return result;
}
Is there any jetty configuration or resteasy configuration for it? Or is there any way to solve this problem? Thanks for your helps.
Which resteasy version are you using? There is a known issue (RESTEASY-467) with Strings in 2.0.1 an prior.
These are your options:
1) force the encoding returning byte[]
public byte[] getPersons
and then
return result.getBytes("UTF8");
2) return List (or create a PersonListing if you need it)
public List<Person> getPersons
and let resteasy handle the json transformation.
3) return a StreamingOutput
NOTE: with this option the "Content-Length" header will be unknown.
return new StreamingOutput()
{
public void write(OutputStream outputStream) throws IOException, WebApplicationException
{
PrintStream writer = new PrintStream(outputStream, true, "UTF-8");
writer.println(result);
}
};
4) upgrade to 2.2-beta-1 or newer version.