Improved the security of the connection between the app window and AI Studio (#1146)

app/Tests/Tools/AppAccess/WebRootFilesTests.cs

@@ -0,0 +1,73 @@
+using AIStudio.Assistants.ERI;
+using AIStudio.Tools;
+
+using Changelog = AIStudio.Components.Changelog;
+
+namespace AIStudio.Tests.Tools.AppAccess;
+
+/// <summary>
+/// Checks that the app reads the files below wwwroot which it shows itself.
+/// </summary>
+/// <remarks>
+/// The changelogs and the ERI specifications come from the files embedded into the app, not from a
+/// request to its own server. A file which is missing there would leave the changelog or the ERI
+/// assistant empty without any error.
+/// </remarks>
+[TestFixture]
+public sealed class WebRootFilesTests
+{
+    private static IEnumerable<string> ChangelogFiles() => Changelog.LOGS.Select(log => log.Filename);
+
+    private static IEnumerable<ERIVersion> SpecificationVersions() => Enum.GetValues<ERIVersion>().Where(version => version.WasSpecificationSelected());
+
+    [TestCaseSource(nameof(ChangelogFiles))]
+    public async Task EveryChangelogCanBeRead(string filename)
+    {
+        var text = await new WebRootFiles().ReadTextAsync($"changelog/{filename}");
+        Assert.That(text, Is.Not.Empty);
+    }
+
+    [TestCaseSource(nameof(SpecificationVersions))]
+    public async Task EveryERISpecificationCanBeRead(ERIVersion version)
+    {
+        var text = await version.ReadSpecification(new WebRootFiles());
+        Assert.That(text, Is.Not.Empty);
+    }
+
+    [Test]
+    public async Task AMissingFileReadsAsEmptyText()
+    {
+        var text = await new WebRootFiles().ReadTextAsync("changelog/does-not-exist.md");
+        Assert.That(text, Is.Empty);
+    }
+
+    [TestCaseSource(nameof(SpecificationVersions))]
+    public async Task EveryERISpecificationCanBeSaved(ERIVersion version)
+    {
+        var webRootFiles = new WebRootFiles();
+        var destinationPath = Path.Combine(Path.GetTempPath(), $"eri-specification-{Guid.NewGuid():N}.json");
+        try
+        {
+            Assert.That(await webRootFiles.CopyToAsync(version.SpecificationURL(), destinationPath), Is.True);
+            Assert.That(await File.ReadAllTextAsync(destinationPath), Is.EqualTo(await version.ReadSpecification(webRootFiles)));
+        }
+        finally
+        {
+            File.Delete(destinationPath);
+        }
+    }
+
+    [Test]
+    public async Task AMissingFileIsNotCopied()
+    {
+        var destinationPath = Path.Combine(Path.GetTempPath(), $"eri-specification-{Guid.NewGuid():N}.json");
+
+        var copied = await new WebRootFiles().CopyToAsync("specs/eri/does-not-exist.json", destinationPath);
+
+        Assert.Multiple(() =>
+        {
+            Assert.That(copied, Is.False);
+            Assert.That(File.Exists(destinationPath), Is.False);
+        });
+    }
+}