.NET Core - Web API - How to do File Upload?
I am not able to figure out, how to write a .NET Core Web API to support File Upload. Please note I am not using ASP.NET Core MVC form for file upload but via a Servlet/JSP container. Here is how my project.json is defined,
{
"dependencies": {
"Microsoft.NETCore.App": {
"version": "1.0.1",
"type": "platform"
},
"Microsoft.AspNetCore.Mvc": "1.0.1",
"Microsoft.AspNetCore.Routing": "1.0.1",
"Microsoft.AspNetCore.Server.IISIntegration": "1.0.0",
"Microsoft.AspNetCore.Server.Kestrel": "1.0.1",
"Microsoft.Extensions.Configuration.EnvironmentVariables": "1.0.0",
"Microsoft.Extensions.Configuration.FileExtensions": "1.0.0",
"Microsoft.Extensions.Configuration.Json": "1.0.0",
"Microsoft.Extensions.Logging": "1.0.0",
"Microsoft.Extensions.Logging.Console": "1.0.0",
"Microsoft.Extensions.Logging.Debug": "1.0.0",
"Microsoft.Extensions.Options.ConfigurationExtensions": "1.0.0",
"Npgsql": "3.1.9",
"CoreCompat.Newtonsoft.Json": "9.0.2-beta001",
"Newtonsoft.Json": "9.0.1"
},
"tools": {
"Microsoft.AspNetCore.Server.IISIntegration.Tools": "1.0.0-preview2-final"
},
"frameworks": {
"netcoreapp1.0": {
"imports": [
"dotnet5.6",
"portable-net45+win8"
]
}
},
"buildOptions": {
"emitEntryPoint": true,
"preserveCompilationContext": true
},
"runtimeOptions": {
"configProperties": {
"System.GC.Server": true
}
},
"publishOptions": {
"include": [
"wwwroot",
"**/*.cshtml",
"appsettings.json",
"web.config"
]
},
"scripts": {
"postpublish": [ "dotnet publish-iis --publish-folder %publish:OutputPath% --framework %publish:FullTargetFramework%" ]
}
}
Here is how my Startup is defined,
using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;
using Microsoft.AspNetCore.Builder;
using Microsoft.AspNetCore.Hosting;
using Microsoft.Extensions.Configuration;
using Microsoft.Extensions.DependencyInjection;
using Microsoft.Extensions.Logging;
using QCService.Models;
namespace QCService
{
public class Startup
{
public Startup(IHostingEnvironment env)
{
var builder = new ConfigurationBuilder()
.SetBasePath(env.ContentRootPath)
.AddJsonFile("appsettings.json", optional: true, reloadOnChange: true)
.AddJsonFile($"appsettings.{env.EnvironmentName}.json", optional: true)
.AddEnvironmentVariables();
Configuration = builder.Build();
}
public IConfigurationRoot Configuration { get; }
// This method gets called by the runtime. Use this method to add services to the container.
public void ConfigureServices(IServiceCollection services)
{
// Add framework services.
services.AddMvc();
//Add SurveysRepository for Dependency Injection
services.AddSingleton<ISurveysRepository, SurveysRepository>();
//Add FeedbacksRepository for Dependency Injection
services.AddSingleton<IFeedbacksRepository, FeedbacksRepository>();
//Add AttachmentsRepository for Dependency Injection
services.AddSingleton<IAttachmentsRepository, AttachmentsRepository>();
}
// This method gets called by the runtime. Use this method to configure the HTTP request pipeline.
public void Configure(IApplicationBuilder app, IHostingEnvironment env, ILoggerFactory loggerFactory)
{
loggerFactory.AddConsole(Configuration.GetSection("Logging"));
loggerFactory.AddDebug();
app.UseMvc();
}
}
}
Finally here is how my Controller is defined,
using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;
using Microsoft.AspNetCore.Mvc;
//Including model classes for Attachments
using QCService.Models;
using Microsoft.AspNetCore.Http;
using Microsoft.AspNetCore.Hosting;
using System.IO;
using Microsoft.Net.Http.Headers;
// For more information on enabling Web API for empty projects, visit http://go.microsoft.com/fwlink/?LinkID=397860
namespace QCService.Controllers
{
[Route("api/[controller]")]
public class AttachmentsController : Controller
{
public IAttachmentsRepository AttachmentItems { get; set; }
public AttachmentsController(IAttachmentsRepository attachmentItems)
{
AttachmentItems = attachmentItems;
}
// GET: api/Attachments
[HttpGet] /*http://localhost:52770/api/Attachments*/
public IEnumerable<Attachments> Get()
{
return AttachmentItems.GetAllAttachments();
}
// GET api/Attachments/5
[HttpGet("{id}")] /*http://localhost:52770/api/Attachments/{AttachmentID}*/
public Attachments Get(int id)
{
return AttachmentItems.GetAttachment(id);
}
// GET api/Attachments/5
[HttpGet("Feedback/{id}")] /*http://localhost:52770/api/Attachments/Feedback/{FeedbackID}*/
public IEnumerable<Attachments> GetFeedbackAttachments(int id)
{
return AttachmentItems.GetFeedbackAttachments(id);
}
// POST api/Attachments
[HttpPost]/*http://localhost:52770/api/Attachments/*/
public async Task<IActionResult> PostFiles(ICollection<IFormFile> files)
{
try
{
System.Console.WriteLine("You received the call!");
WriteLog("PostFiles call received!", true);
//We would always copy the attachments to the folder specified above but for now dump it wherver....
long size = files.Sum(f => f.Length);
// full path to file in temp location
var filePath = Path.GetTempFileName();
var fileName = Path.GetTempFileName();
foreach (var formFile in files)
{
if (formFile.Length > 0)
{
using (var stream = new FileStream(filePath, FileMode.Create))
{
await formFile.CopyToAsync(stream);
//formFile.CopyToAsync(stream);
}
}
}
// process uploaded files
// Don't rely on or trust the FileName property without validation.
//Displaying File Name for verification purposes for now -Rohit
return Ok(new { count = files.Count, fileName, size, filePath });
}
catch (Exception exp)
{
System.Console.WriteLine("Exception generated when uploading file - " + exp.Message);
WriteLog("Exception generated when uploading file - " + exp.Message, true);
string message = $"file / upload failed!";
return Json(message);
}
}
/// <summary>
/// Writes a log entry to the local file system
/// </summary>
/// <param name="Message">Message to be written to the log file</param>
/// <param name="InsertNewLine">Inserts a new line</param>
public void WriteLog(string Message, bool InsertNewLine)
{
LogActivity ologObject = null;
try
{
string MessageString = (InsertNewLine == true ? Environment.NewLine : "") + Message;
if (ologObject == null)
ologObject = LogActivity.GetLogObject();
ologObject.WriteLog(Message, InsertNewLine);
}
catch (Exception ex)
{
Console.WriteLine("Unable to write to the log file : " + ex.Message);
Console.WriteLine("Stack Trace : " + ex.StackTrace);
}
}
}
}
I have gone through this link, https://docs.microsoft.com/en-us/aspnet/core/mvc/models/file-uploads but just can't make it work! Any help is appreciated!!!
I am using the Google's Advanced Rest Client to post the data as follows, This is how I am sending the POST request
I keep getting response failed with following message... Status: 500: Internal Server Error Loading time: 62 ms Response headers 5 Request headers 2 Redirects 0 Timings Content-Type: multipart/form-data; boundary=----WebKitFormBoundary0RKUhduCjSNZOEMN Content-Length: 9106 Source message
POST /api/Attachments HTTP/1.1 HOST: localhost:52770 content-type: multipart/form-data; boundary=----WebKitFormBoundary0RKUhduCjSNZOEMN content-length: 9106
------WebKitFormBoundary0RKUhduCjSNZOEMN Content-Disposition: form-data; name="fileUpload1"; filename="1i4ymeoyov_In_the_Wild_Testing.png" Content-Type: image/png
�PNG
IHDR,I�3(tEXtSoftwareAdobe ImageReadyq�e< iTXtXML:com.adobe.xmp �8 ^2IDATx��] pU����@ a�H� Pe�P8 ��Ȉ��b�̌3�p�q�*�7"�h�+Yf��O�atD��(<�h¦DLXdOH ������=}���}ov8_U�..... ------WebKitFormBoundary0RKUhduCjSNZOEMN--
Answer
This is the root cause: form-data; name="fileUpload1"
Your name "fileUpload1" has to be "files" which matches the declaration of the action PostFiles(ICollection< IFormFile> files)