WIP: Process Uploaded Images

AllReady.Processing.UnitTest/AllReady.Processing.UnitTest.csproj

@@ -0,0 +1,22 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+    <TargetFramework>netcoreapp2.0</TargetFramework>
+
+    <IsPackable>false</IsPackable>
+  </PropertyGroup>
+
+  <ItemGroup>
+    <PackageReference Include="Microsoft.NET.Test.Sdk" Version="15.5.0" />
+    <PackageReference Include="Moq" Version="4.8.1" />
+    <PackageReference Include="Shouldly" Version="3.0.0" />
+    <PackageReference Include="xunit" Version="2.3.1" />
+    <PackageReference Include="xunit.runner.visualstudio" Version="2.3.1" />
+    <DotNetCliToolReference Include="dotnet-xunit" Version="2.3.1" />
+  </ItemGroup>
+
+  <ItemGroup>
+    <ProjectReference Include="..\AllReady.Processing\AllReady.Processing\AllReady.Processing.csproj" />
+  </ItemGroup>
+
+</Project>

AllReady.Processing.UnitTest/ImageHelpers.cs

@@ -0,0 +1,31 @@
+using System.IO;
+using Shouldly;
+using SixLabors.ImageSharp;
+using SixLabors.ImageSharp.Formats;
+
+namespace AllReady.Processing.UnitTest
+{
+    public static class ImageHelpers
+    {
+        public static Stream GetImageStream(int width, int height, IImageFormat format = null)
+        {
+            var stream = new MemoryStream();
+            using (var img = new Image<Rgba32>(width, height))
+            {
+                img.Save(stream, format ?? ImageFormats.Png);
+            }
+
+            stream.Seek(0, SeekOrigin.Begin);
+            return stream;
+        }
+
+        public static void ShouldBeImageWithDimensions(this Stream stream, int width, int height)
+        {
+            using (var img = Image.Load<Rgba32>(stream))
+            {
+                img.Width.ShouldBe(width);
+                img.Height.ShouldBe(height);
+            }
+        }
+    }
+}

AllReady.Processing.UnitTest/ImageResizeShould.cs

@@ -0,0 +1,100 @@
+using System;
+using System.Collections.Generic;
+using System.Diagnostics;
+using System.IO;
+using Microsoft.Azure.WebJobs.Host;
+using Moq;
+using Shouldly;
+using SixLabors.ImageSharp;
+using SixLabors.ImageSharp.Formats;
+using Xunit;
+
+namespace AllReady.Processing.UnitTest
+{
+    public class ImageResizeShould
+    {
+        private const string BlobName = "/container/image.png";
+        private readonly TraceWriter _log = new Mock<TraceWriter>(TraceLevel.Verbose).Object;
+
+        public ImageResizeShould()
+        {
+            Environment.SetEnvironmentVariable("maxDimension", "400");
+        }
+
+        [Fact]
+        public void Not_resize_an_image_within_maxDimensions_in_both_directions()
+        {
+            using (var src = ImageHelpers.GetImageStream(400, 400))
+            using (var result = new MemoryStream())
+            {
+                ImageResize.Run(src, BlobName, result, _log);
+
+                result.Seek(0, SeekOrigin.Begin);
+                result.ReadByte().ShouldBe(-1);
+            }
+        }
+
+        [Fact]
+        public void Resize_an_image_with_width_larger_than_maxDimensions()
+        {
+            using (var src = ImageHelpers.GetImageStream(700, 400))
+            using (var result = new MemoryStream())
+            {
+                ImageResize.Run(src, BlobName, result, _log);
+
+                result.Seek(0, SeekOrigin.Begin);
+                result.ShouldBeImageWithDimensions(400, 228);
+            }
+        }
+
+        [Fact]
+        public void Resize_an_image_with_height_larger_than_maxDimensions()
+        {
+            using (var src = ImageHelpers.GetImageStream(250, 500))
+            using (var result = new MemoryStream())
+            {
+                ImageResize.Run(src, BlobName, result, _log);
+
+                result.Seek(0, SeekOrigin.Begin);
+                result.ShouldBeImageWithDimensions(200, 400);
+            }
+        }
+
+        [Fact]
+        public void Resize_an_image_with_both_dimensions_larger_than_maxDimensions()
+        {
+            using (var src = ImageHelpers.GetImageStream(500, 650))
+            using (var result = new MemoryStream())
+            {
+                ImageResize.Run(src, BlobName, result, _log);
+
+                result.Seek(0, SeekOrigin.Begin);
+                result.ShouldBeImageWithDimensions(307, 400);
+            }
+        }
+
+        public static readonly IEnumerable<object[]> TestImageFormats =
+            new[]
+            {
+                new object[] {ImageFormats.Png},
+                new object[] {ImageFormats.Gif},
+                new object[] {ImageFormats.Bmp},
+                new object[] {ImageFormats.Jpeg}
+            };
+
+        [Theory]
+        [MemberData(nameof(TestImageFormats))]
+        public void Maintain_the_same_image_format_when_resizing(IImageFormat expected)
+        {
+            using (var src = ImageHelpers.GetImageStream(500, 650, expected))
+            using (var result = new MemoryStream())
+            {
+                ImageResize.Run(src, BlobName, result, _log);
+
+                result.Seek(0, SeekOrigin.Begin);
+                var format = Image.DetectFormat(result);
+                format.ShouldBe(format);
+            }
+        }
+    }
+}

AllReady.Processing.UnitTest/QueueTestShould.cs

@@ -0,0 +1,21 @@
+using System.Diagnostics;
+using Microsoft.Azure.WebJobs.Host;
+using Moq;
+using Xunit;
+
+namespace AllReady.Processing.UnitTest
+{
+    public class QueueTestShould
+    {
+        [Fact]
+        public void Log_that_the_queue_message_was_dequeued()
+        {
+            string item = "Test Item";
+            var mockTraceWriter = new Mock<TraceWriter>(TraceLevel.Verbose);
+
+            QueueTest.Run(item, mockTraceWriter.Object);
+
+            mockTraceWriter.Verify(x => x.Trace(It.Is<TraceEvent>(e => e.Level == TraceLevel.Info && e.Message.Contains(item))), Times.Once);
+        }
+    }
+}

AllReady.Processing/AllReady.Processing.sln

@@ -1,9 +1,11 @@
 
 Microsoft Visual Studio Solution File, Format Version 12.00
 # Visual Studio 15
-VisualStudioVersion = 15.0.27130.2027
+VisualStudioVersion = 15.0.27130.2026
 MinimumVisualStudioVersion = 10.0.40219.1
-Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "AllReady.Processing", "AllReady.Processing\AllReady.Processing.csproj", "{C619B518-08A3-4CFC-BC22-CB0B4A63CB31}"
+Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "AllReady.Processing", "AllReady.Processing\AllReady.Processing.csproj", "{C619B518-08A3-4CFC-BC22-CB0B4A63CB31}"
+EndProject
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "AllReady.Processing.UnitTest", "..\AllReady.Processing.UnitTest\AllReady.Processing.UnitTest.csproj", "{CBA25B72-7C92-4C78-ABF6-1E35079214B5}"
 EndProject
 Global
 	GlobalSection(SolutionConfigurationPlatforms) = preSolution
@@ -15,6 +17,10 @@ Global
 		{C619B518-08A3-4CFC-BC22-CB0B4A63CB31}.Debug|Any CPU.Build.0 = Debug|Any CPU
 		{C619B518-08A3-4CFC-BC22-CB0B4A63CB31}.Release|Any CPU.ActiveCfg = Release|Any CPU
 		{C619B518-08A3-4CFC-BC22-CB0B4A63CB31}.Release|Any CPU.Build.0 = Release|Any CPU
+		{CBA25B72-7C92-4C78-ABF6-1E35079214B5}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{CBA25B72-7C92-4C78-ABF6-1E35079214B5}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{CBA25B72-7C92-4C78-ABF6-1E35079214B5}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{CBA25B72-7C92-4C78-ABF6-1E35079214B5}.Release|Any CPU.Build.0 = Release|Any CPU
 	EndGlobalSection
 	GlobalSection(SolutionProperties) = preSolution
 		HideSolutionNode = FALSE

AllReady.Processing/AllReady.Processing/AllReady.Processing.csproj

@@ -1,9 +1,10 @@
 <Project Sdk="Microsoft.NET.Sdk">
   <PropertyGroup>
-    <TargetFramework>net461</TargetFramework>
+    <TargetFramework>netstandard2.0</TargetFramework>
   </PropertyGroup>
   <ItemGroup>
-    <PackageReference Include="Microsoft.NET.Sdk.Functions" Version="1.0.6" />
+    <PackageReference Include="Microsoft.NET.Sdk.Functions" Version="1.0.8" />
+    <PackageReference Include="SixLabors.ImageSharp" Version="1.0.0-beta0002" />
   </ItemGroup>
   <ItemGroup>
     <Reference Include="Microsoft.CSharp" />

AllReady.Processing/AllReady.Processing/Configuration.cs

@@ -0,0 +1,13 @@
+using System;
+
+namespace AllReady.Processing
+{
+    public static class Configuration
+    {
+        public static string GetEnvironmentVariable(string key, string defaultValue = "") =>
+            Environment.GetEnvironmentVariable(key) ?? defaultValue;
+
+        public static int GetEnvironmentVariableAsInt(string key, int defaultValue = 0) =>
+            int.Parse(GetEnvironmentVariable(key, defaultValue.ToString()));
+    }
+}

AllReady.Processing/AllReady.Processing/ImageResize.cs

@@ -0,0 +1,42 @@
+using System;
+using System.IO;
+using Microsoft.Azure.WebJobs;
+using Microsoft.Azure.WebJobs.Host;
+using SixLabors.ImageSharp;
+using SixLabors.ImageSharp.Formats;
+
+namespace AllReady.Processing
+{
+    public class ImageResize
+    {
+        [FunctionName("ImageResize")]
+        public static void Run(
+            [BlobTrigger("images/{name}")] Stream imageBlob,
+            string name,
+            [Blob("images/{name}", FileAccess.Write)] Stream outputBlob,
+            TraceWriter log)
+        {
+            int maxDimension = Configuration.GetEnvironmentVariableAsInt("maxDimension", 800);
+            using (var img = Image.Load<Rgba32>(imageBlob, out IImageFormat imageFormat))
+            {
+                int bigDimension = Math.Max(img.Width, img.Height);
+                if (bigDimension <= maxDimension)
+                {
+                    log.Info($"Image {name} does not need resizing.");
+                    return;
+                }
+
+                double ratio = bigDimension == img.Width
+                    ? (double) maxDimension / img.Width
+                    : (double) maxDimension / img.Height;
+                int width = (int) (img.Width * ratio);
+                int height = (int) (img.Height * ratio);
+
+                log.Info($"Resizing image {name} to {width}x{height}");
+                img.Mutate(ctx => ctx.Resize(width, height));
+
+                img.Save(outputBlob, imageFormat);
+            }
+        }
+    }
+}

AllReady.Processing/AllReady.Processing/QueueTest.cs

@@ -10,7 +10,7 @@ public static class QueueTest
         // local storage emulator.
 
         [FunctionName("QueueTest")]
-        public static void Run([QueueTrigger("queue-test", Connection = "")]string item, TraceWriter log)
+        public static void Run([QueueTrigger("queue-test")]string item, TraceWriter log)
         {            
             log.Info($"A message was dequeued from the queue-test queue: {item}");
         }