Added simple support for image upload and requesting

Wave/Components/Pages/Upload.razor

@@ -0,0 +1,58 @@
+@page "/upload"
+
+@using Microsoft.AspNetCore.Authorization
+@using Wave.Services
+@using System.IO.Pipelines
+
+@attribute [Authorize]
+@rendermode InteractiveServer
+@inject ImageService ImageService
+
+<PageTitle>Upload</PageTitle>
+
+<h3 class="title mb-3">Upload</h3>
+@if (Busy) {
+    <progress class="progress progress-primary w-56"></progress>
+} 
+<div>
+    <p>@Message</p>
+    @if (Path is not null) {
+        <img src="@Path" type="@ImageService.ImageMimeType" width="800" alt="" />
+    }
+</div>
+
+<InputFile OnChange="@LoadFiles" accept="image/png, image/jpeg, image/webp" />
+
+@code {
+    private const long MaxFileSize = 1024 * 1024 * 5; // 5MB should be fine
+    private string Message { get; set; } = string.Empty;
+    private string? Path { get; set; }
+    private bool Busy { get; set; }
+
+    private async Task LoadFiles(InputFileChangeEventArgs args) {
+        Busy = true;
+
+        try {
+            string tempName = System.IO.Path.GetRandomFileName();
+            string tempDirectory = System.IO.Path.Combine(".", "files", "temp");
+            Directory.CreateDirectory(tempDirectory);
+            string tempPath = System.IO.Path.Combine(tempDirectory, tempName);
+            await using var fs = new FileStream(tempPath, FileMode.Create);
+            await args.File.OpenReadStream(MaxFileSize).CopyToAsync(fs);
+
+            var guid = await ImageService.StoreImageAsync(tempPath);
+
+            if (guid is null) {
+                Message = "Image upload failed";
+            } else {
+                Message = "Image uploaded successfully";
+                Path = "/images/" + guid;
+            }
+        } catch (Exception ex) {
+            Message = $"{ex.Message} ({ex.GetType().Name}).";
+        } finally {
+            Busy = false;
+        }
+    }
+
+}

Wave/Controllers/ImageController.cs

@@ -0,0 +1,20 @@
+using Microsoft.AspNetCore.Http.HttpResults;
+using Microsoft.AspNetCore.Mvc;
+using Wave.Services;
+
+namespace Wave.Controllers;
+
+[ApiController]
+[Route("/images")]
+public class ImageController(ImageService imageService) : ControllerBase {
+    private ImageService ImageService { get; } = imageService;
+
+    [HttpGet]
+    [Route("{imageId:guid}")]
+    public IActionResult Get(Guid imageId) {
+        string? path = ImageService.GetPath(imageId);
+
+        if (path is null) return NotFound();
+        return File(System.IO.File.OpenRead(path), ImageService.ImageMimeType);
+    }
+}

Wave/Dockerfile

@@ -3,6 +3,7 @@
 FROM mcr.microsoft.com/dotnet/aspnet:8.0 AS base
 USER app
 WORKDIR /app
+RUN mkdir ./files && chown app ./files
 EXPOSE 8080
 
 FROM mcr.microsoft.com/dotnet/sdk:8.0 AS build
@@ -21,5 +22,4 @@ RUN dotnet publish "./Wave.csproj" -c $BUILD_CONFIGURATION -o /app/publish /p:Us
 FROM base AS final
 WORKDIR /app
 COPY --from=publish /app/publish .
-RUN mkdir ./files
 ENTRYPOINT ["dotnet", "Wave.dll"]

Wave/Services/ImageService.cs

@@ -0,0 +1,50 @@
+using ImageMagick;
+
+namespace Wave.Services;
+
+public class ImageService(ILogger<ImageService> logger) {
+    private ILogger<ImageService> Logger { get; } = logger;
+    private const string BasePath = "./files/images";
+    private const string ImageExtension = ".jpg";
+    public string ImageMimeType => "image/jpg";
+
+    public string? GetPath(Guid imageId) {
+        string path = Path.Combine(BasePath, imageId + ImageExtension);
+        return File.Exists(path) ? path : null;
+    }
+
+    public async ValueTask<Guid?> StoreImageAsync(string temporaryPath, int size = 800, CancellationToken cancellation = default) {
+        if (File.Exists(temporaryPath) is not true) return null;
+
+        try {
+            if (File.Exists(BasePath) is not true) Directory.CreateDirectory(BasePath);
+
+            var image = new MagickImage();
+            await image.ReadAsync(temporaryPath, cancellation);
+
+            // Jpeg with 90% compression should look decent
+            image.Resize(new MagickGeometry(size)); // this preserves aspect ratio
+            image.Format = MagickFormat.Jpeg;
+            image.Quality = 90;
+
+            if (image.GetExifProfile() is not null) {
+                image.RemoveProfile(image.GetExifProfile());
+            }
+
+            // Overwrite exif for privacy reasons
+            var exif = new ExifProfile {
+                Parts = ExifParts.None
+            };
+            exif.CreateThumbnail();
+            image.SetProfile(exif);
+            
+            var guid = Guid.NewGuid();
+            string path = Path.Combine(BasePath, guid + ImageExtension);
+            await image.WriteAsync(path, cancellation);
+            return guid;
+        } catch (Exception ex) {
+            Logger.LogInformation(ex, "Failed to process uploaded image.");
+            return null;
+        }
+    }
+}

Wave/Wave.csproj

@@ -10,6 +10,7 @@
   </PropertyGroup>
 
   <ItemGroup>
+    <PackageReference Include="Magick.NET-Q8-AnyCPU" Version="13.5.0" />
     <PackageReference Include="Microsoft.AspNetCore.Diagnostics.EntityFrameworkCore" Version="8.0.0" />
     <PackageReference Include="Microsoft.AspNetCore.Identity.EntityFrameworkCore" Version="8.0.0" />
     <PackageReference Include="Microsoft.EntityFrameworkCore.SqlServer" Version="8.0.0" />
@@ -19,6 +20,8 @@
   </ItemGroup>
 
   <ItemGroup>
+    <Folder Include="Controllers\" />
+    <Folder Include="Services\" />
     <Folder Include="wwwroot\img\" />
   </ItemGroup>