Upload file with httpclient

CloseableHttpClient; import org. HttpClients; import org. BufferedReader ;. File ;. IOException ;. InputStreamReader ;. HttpEntity ;. HttpResponse ;. HttpUriRequest ;. RequestBuilder ;. MultipartEntityBuilder ;. CloseableHttpClient ;. HttpClients ;. Test ;. Response :. Default test. Tests run : 1 , Failures : 0 , Skips : 0. Deepak Verma. MultipartRequestHelper has 2 functions:.

In the client side, I will show you how to send this information. Now, the procedure is starting to read each section of the multipart request. The section could contain a file or form data. If it is a form section, I read its body and try to match the name with a known variable. For using the HttpContextAccessor remember to add in the Startup. Then, I like to have a nice URL to share and for this reason I replace the extension with a number and then the new name of the file like that.

So, the resulted URL is quite easy to read and write. If you are thinking why I want to have a nice URL, the answer is easy. So, I want to have a functionality to upload file and display a nice URL. The following code snippet shows an example solution. So, the method UploadFile string filePath first validates the physical file.

Then line 10 instantiates a MultipartFormDataContent object, which is the request content sent to the server-side app. The key can be different when multiple files are included in a form. The values can only be represented as strings, and the server-side app will have to parse them into correct data types.

It is important to check what kind of file the procedure is going to save on the file system to avoid attach of any kind. For this reason, in the FileHelpers I want to check the header of the uploading file to be sure is a genuine file. So, for that, we can read the header of a file.

If you see the code of this helper, you see this definition:. So, the procedure receives from the FormData the image in byte[]. The HttpClient here is org apache. This way, similar to the above, only becomes FileBody.

The Part array above corresponds to HttpEntity here. No matter which way the client uploads, the server handles it the same way.

After obtaining the parameters through HttpServletRequest, the resulting Item is classified into ordinary forms and File forms. After processing, the server can set the simple information returned to the client in Header. If the return client is a stream, the size of the stream must be set in advance! The most basic function of HttpClient is to implement the Http method. The complete source code is in my GitHub repository. The implementation is lengthy, but the code logic demonstrates several checks to meet the security criteria.

The following code snippet shows the example action method. In the code above, lines 22 to 47 handle the File Disposition, and lines 48 to 65 handle the Form Disposition. When the MultipartReader reads sections in the HTTP request body, the request content is parsed and saved to physical disk file and memory form data. This API action method finds the file and converts the file to an array of bytes, then returns a FileContentResult with the byte array and metadata.

The following code snippet shows an example. The following code snippet shows an example solution. The method UploadFile string filePath first validates the physical file. Then line 13 instantiates a MultipartFormDataContent object, which is the request content sent to the server side app.