Merge pull request #254 from jetelain/s2cproxy

S2C proxy

ArmaRealMapWebSite/Controllers/S2CController.cs

@@ -0,0 +1,83 @@
+using System;
+using System.IO;
+using System.Net.Http;
+using System.Threading;
+using System.Threading.Tasks;
+using Microsoft.AspNetCore.Mvc;
+using Microsoft.Extensions.Logging;
+using SixLabors.ImageSharp;
+
+namespace ArmaRealMapWebSite.Controllers
+{
+    public class S2CController : Controller
+    {
+        private readonly string cacheLocation = Path.Combine(Environment.GetFolderPath(Environment.SpecialFolder.LocalApplicationData), "GameRealisticMap", "S2CloudlessCache");
+        private readonly SemaphoreSlim downloadSemaphore = new SemaphoreSlim(1, 1);
+
+        private readonly HttpClient httpClient;
+        private readonly ILogger<S2CController> logger;
+
+        public S2CController(IHttpClientFactory httpClientFactory, ILogger<S2CController> logger)
+        {
+            this.httpClient = httpClientFactory.CreateClient("S2C");
+            this.logger = logger;
+        }
+
+        [Route("sat/{dataset}/{zoom}/{y}/{x}.jpg")]
+        public async Task<ActionResult> GetTile(string dataset, int zoom, int y, int x)
+        {
+            if (dataset != "s2cloudless-2020" || zoom > 16 || zoom < 0 || x < 0 || y < 0)
+            {
+                return NotFound();
+            }
+            var endPoint = "https://tiles.maps.eox.at/wmts/1.0.0/s2cloudless-2020_3857/default/GoogleMapsCompatible/";
+            var filePath = FormattableString.Invariant($"{zoom}/{y}/{x}.jpg");
+            var cacheFile = System.IO.Path.Combine(cacheLocation, filePath);
+            if (!System.IO.File.Exists(cacheFile))
+            {
+                await downloadSemaphore.WaitAsync().ConfigureAwait(false);
+                try
+                {
+                    if (!System.IO.File.Exists(cacheFile))
+                    {
+                        Directory.CreateDirectory(Path.GetDirectoryName(cacheFile));
+                        var bytes = await Load(new Uri(endPoint + filePath, UriKind.Absolute)).ConfigureAwait(false);
+                        var id = Image.DetectFormat(bytes);
+                        if (id.DefaultMimeType == "image/jpeg")
+                        {
+                            await System.IO.File.WriteAllBytesAsync(cacheFile, bytes);
+                        }
+                    }
+                }
+                finally
+                {
+                    downloadSemaphore.Release();
+                }
+            }
+            if (!System.IO.File.Exists(cacheFile))
+            {
+                return NotFound();
+            }
+            return File(await System.IO.File.ReadAllBytesAsync(cacheFile), "image/jpeg");
+        }
+
+        private async Task<byte[]> Load(Uri uri)
+        {
+            int sleep = 10;
+            while (sleep < 5000)
+            {
+                await Task.Delay(sleep).ConfigureAwait(false);
+                try
+                {
+                    return await httpClient.GetByteArrayAsync(uri).ConfigureAwait(false);
+                }
+                catch (Exception ex)
+                {
+                    logger.Log(LogLevel.Warning, "{0}: {1}", uri.OriginalString, ex.Message);
+                }
+                sleep += 500;
+            }
+            throw new ApplicationException($"Failed to load '{uri}'");
+        }
+    }
+}

ArmaRealMapWebSite/Startup.cs

@@ -53,6 +53,12 @@ public void ConfigureServices(IServiceCollection services)
                 );
             });
 
+            services.AddHttpClient("S2C", c => { 
+            
+                c.DefaultRequestHeaders.Add("User-Agent", "Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:109.0) Gecko/20100101 Firefox/111.0");
+
+            });
+
             if (Environment.OSVersion.Platform == PlatformID.Unix)
             {
                 services.AddDataProtection()