Azure Blob Storage feature is added. (#16)

* Azure Blob Storage support.

* Max age is linked with configuration

Author: selcukusta

.gitignore

@@ -1,4 +1,5 @@
 .vs/
+.vscode/
 hurimg.core/bin/
 hurimg.core/obj/
 ImageServer.Core/bin/

.vscode/launch.json

@@ -1,12 +1,12 @@
-FROM mcr.microsoft.com/dotnet/core/sdk:3.1 AS build
+FROM mcr.microsoft.com/dotnet/core/sdk:3.1.201-buster AS build
 WORKDIR /app/image-server
 
 # copy everything and build app
 COPY ./ImageServer.Core .
-RUN dotnet publish -c Release -o out
+RUN dotnet publish -c Release -r linux-x64 -o out
 
 # build runtime image
-FROM mcr.microsoft.com/dotnet/core/aspnet:3.1
+FROM mcr.microsoft.com/dotnet/core/runtime-deps:3.1.3-buster-slim  as final
 COPY --from=build /app/image-server/out ./app
 WORKDIR /app
-ENTRYPOINT ["dotnet", "ImageServer.Core.dll"]
+ENTRYPOINT ["./ImageServer.Core"]

.vscode/tasks.json

@@ -1,10 +1,12 @@
 using System;
+using System.Globalization;
 using System.Linq;
 using System.Net;
 using System.Threading.Tasks;
 using ImageServer.Core.Services;
 using Microsoft.AspNetCore.Mvc;
 using Microsoft.AspNetCore.WebUtilities;
+using Microsoft.Extensions.Configuration;
 using Microsoft.Extensions.Logging;
 
 namespace ImageServer.Core.Controllers
@@ -14,12 +16,14 @@ public class ImageController : Controller
         private readonly IFileAccessService _fileService;
         private readonly IImageService _imageService;
         private readonly ILogger<ImageController> _logger;
+        private readonly IConfiguration _configuration;
 
-        public ImageController(IFileAccessService fileService, IImageService imageService, ILogger<ImageController> logger)
+        public ImageController(IFileAccessService fileService, IImageService imageService, ILogger<ImageController> logger, IConfiguration configuration)
         {
             _fileService = fileService ?? throw new ArgumentNullException(nameof(fileService));
             _imageService = imageService ?? throw new ArgumentNullException(nameof(imageService));
             _logger = logger ?? throw new ArgumentNullException(nameof(logger));
+            _configuration = configuration ?? throw new ArgumentNullException(nameof(configuration));
         }
 
         [HttpGet("/i/{slug}/{quality:range(0,100)}/{w:range(0,5000)}x{h:range(0,5000)}/{options:opt}/{id:gridfs}")]
@@ -28,7 +32,11 @@ public ImageController(IFileAccessService fileService, IImageService imageServic
         [HttpGet("/i/{slug}/{quality:range(0,100)}/{w:range(0,5000)}x{h:range(0,5000)}/{*id}")]
         public async Task<IActionResult> ImageAsync(string id, string slug, int w, int h, int quality, string options = "")
         {
-            Response.Headers.Add("Cache-Control", $"public, max-age={TimeSpan.FromDays(1).TotalSeconds}");
+            if (!int.TryParse(_configuration.GetValue<string>("CacheControlMaxAgeDay"), NumberStyles.Integer, CultureInfo.InvariantCulture, out int maxAgeDay))
+            {
+                maxAgeDay = 1;
+            }
+            Response.Headers.Add("Cache-Control", $"public, max-age={TimeSpan.FromDays(maxAgeDay).TotalSeconds}");
             Response.Headers.Add("Access-Control-Allow-Origin", "*");
 
             if (string.IsNullOrWhiteSpace(id))
@@ -49,7 +57,11 @@ public async Task<IActionResult> ImageAsync(string id, string slug, int w, int h
         [HttpGet("/i/{slug}/{*filepath}")]
         public async Task<IActionResult> ImageFromFilePathAsync(string filepath, string slug)
         {
-            Response.Headers.Add("Cache-Control", $"public, max-age={TimeSpan.FromDays(1).TotalSeconds}");
+            if (!int.TryParse(_configuration.GetValue<string>("CacheControlMaxAgeDay"), NumberStyles.Integer, CultureInfo.InvariantCulture, out int maxAgeDay))
+            {
+                maxAgeDay = 1;
+            }
+            Response.Headers.Add("Cache-Control", $"public, max-age={TimeSpan.FromDays(maxAgeDay).TotalSeconds}");
             Response.Headers.Add("Access-Control-Allow-Origin", "*");
             return await ImageResult(filepath, slug);
         }

Dockerfile

@@ -17,6 +17,7 @@
     <None Remove="wwwroot\**" />
   </ItemGroup>
   <ItemGroup>
+    <PackageReference Include="Azure.Storage.Blobs" Version="12.4.1" />
     <PackageReference Include="Google.Cloud.Storage.V1" Version="2.5.0" />
     <PackageReference Include="Magick.NET-Q16-AnyCPU" Version="7.15.4" />
     <PackageReference Include="Microsoft.Extensions.Configuration.UserSecrets" Version="3.1.2" />

ImageServer.Core/Controllers/ImageController.cs

@@ -0,0 +1,28 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+
+namespace ImageServer.Core.Model
+{
+    public class AzureBlobContainer
+    {
+        public string ContainerClientName { get; }
+        public string BlobClientName { get; }
+        public AzureBlobContainer(HostConfig host, string fullQualifiedName)
+        {
+            if (string.IsNullOrEmpty(fullQualifiedName))
+            {
+                throw new ArgumentNullException(nameof(fullQualifiedName));
+            }
+
+            var splitted = fullQualifiedName.Split("/");
+            if (splitted == null || !splitted.Any() || splitted.Length < 2)
+            {
+                throw new Exception("Fully qualified name should have at least two parts. For instance; /container/client-path");
+            }
+
+            ContainerClientName = string.IsNullOrWhiteSpace(host.Backend) ? splitted.FirstOrDefault() : host.Backend;
+            BlobClientName = string.Join("/", string.IsNullOrWhiteSpace(host.Backend) ? splitted.Skip(1) : splitted);
+        }
+    }
+}

ImageServer.Core/ImageServer.Core.csproj

@@ -27,6 +27,7 @@ public enum HostType
         GridFs = 1,
         Web = 2,
         GoogleBucket = 3,
+        Azure = 4,
     }
 
 }

ImageServer.Core/Model/AzureBlobContainer.cs

@@ -18,7 +18,8 @@ public static IHostBuilder CreateHostBuilder(string[] args)
             var hostBuilder = Host.CreateDefaultBuilder(args)
                 .ConfigureAppConfiguration((hostingContext, config) =>
                 {
-                    config.SetBasePath(Path.Combine(Directory.GetCurrentDirectory(),"conf"));
+                    config.SetBasePath(Path.Combine(Directory.GetCurrentDirectory(), "conf"));
+                    config.AddEnvironmentVariables("IMAGESERVER_");
                     config.AddJsonFile("appsettings.json", optional: false, reloadOnChange: true);
                 })
               .ConfigureWebHostDefaults(webBuilder =>

ImageServer.Core/Model/HostConfig.cs

@@ -0,0 +1,49 @@
+using System;
+using System.IO;
+using System.Threading.Tasks;
+using Azure.Storage.Blobs;
+using Google.Cloud.Storage.V1;
+using ImageServer.Core.Model;
+using Microsoft.Extensions.Configuration;
+
+namespace ImageServer.Core.Services.FileAccess
+{
+    public class AzureBlobStorageAccess : IFileAccessStrategy
+    {
+        public string ConnectionString { get; }
+        public AzureBlobStorageAccess(IConfiguration configuration)
+        {
+            this.ConnectionString = configuration.GetValue<string>("AzureConnectionString");
+        }
+
+        public async Task<byte[]> GetFileAsync(HostConfig host, string file)
+        {
+            try
+            {
+                AzureBlobContainer container = new AzureBlobContainer(host, file);
+
+                BlobServiceClient serviceClient = new BlobServiceClient(ConnectionString);
+                var containerClient = serviceClient.GetBlobContainerClient(container.ContainerClientName);
+                if (!await containerClient.ExistsAsync())
+                {
+                    throw new FileNotFoundException(file);
+                }
+
+                var blobClient = containerClient.GetBlobClient(container.BlobClientName);
+                if (!await blobClient.ExistsAsync())
+                {
+                    throw new FileNotFoundException(file);
+                }
+
+                using var stream = new MemoryStream();
+                var download = await blobClient.DownloadAsync();
+                await download.Value.Content.CopyToAsync(stream);
+                return stream.GetBuffer();
+            }
+            catch (Exception)
+            {
+                throw;
+            }
+        }
+    }
+}