Build a .NET Core Image Conversion MicroService using LEADTOOLS NuGet Packages

1. Right-Click the project and select Manage NuGet Packages. This will take you to the NuGet Package Manager where you can browse the four NuGets in the search bar.
2. Select the NuGet package and hit Install.
3. Accept the License Acceptance.

using System;
using System.IO;
using Leadtools;
using Leadtools.Codecs;
using Microsoft.AspNetCore.Mvc;

namespace ImageConversion.Controllers
{
    [Route("api/[controller]")]
    public class ImagingController : Controller
    {
        private static void UnlockLeadtools()
        {
            // Embed your license. Use https://www.leadtools.com/support/forum/posts/t12341-HOW-TO--Embed-LEADTOOLS-License-and-Key-in-your-application for a refernce
            string licString =
                     @"[License]
                     License = <doc><ver>2.0</ver><code>INSERT LICENSE HERE</code></doc>";

            byte[] licBytes = System.Text.Encoding.UTF8.GetBytes(licString);
            string key = "INSERT DEV KEY HERE";
            RasterSupport.SetLicense(licBytes, key);
        }

        public ActionResult Get(Uri url, int pageNumber)
        {
            UnlockLeadtools();

            const string mimeType = "image/png";

            if (url == null)
                return Content("url cannot be null");
            if (!url.IsAbsoluteUri)
                return Content("url must be absolute. Make sure to include the protocol.");

            string targetFile = null;
            
            try
            {
                targetFile = Path.GetTempFileName();
                using (RasterCodecs codecs = new RasterCodecs())
                {
                    int totalPages = codecs.GetTotalPages(url).Result;
                    if (pageNumber < 1 )
                    {
                        pageNumber = 1;                                            
                    }
                    else if (pageNumber > totalPages)
                    {
                        pageNumber = totalPages;
                    }
                    RasterImage image = codecs.Load(url, pageNumber).Result;
                    codecs.Save(image, targetFile, RasterImageFormat.Png, 0);
                }

                // Load converted file and return.
                byte[] buffer = System.IO.File.ReadAllBytes(targetFile);
                return File(buffer, mimeType);
            }
            catch (Exception ex)
            {
                return Content(ex.Message);
            }
            finally
            {
                // Clean up
                if (targetFile != null && System.IO.File.Exists(targetFile))
                    System.IO.File.Delete(targetFile);
            }
        }                
    }
}