Fixed an incomplete plugin start with extensive enterprise configurations (#1033)

app/Tests/Chat/FileAttachmentSerializationTests.cs

@@ -0,0 +1,77 @@
+using System.Text.Json;
+
+using AIStudio.Chat;
+using AIStudio.Settings;
+
+namespace AIStudio.Tests.Chat;
+
+/// <summary>
+/// Checks that storing a file attachment never asks the file system about it.
+/// </summary>
+/// <remarks>
+/// Whether the file still exists is a question to the file system, and on a network share which is
+/// out of reach it takes until the SMB timeout to get an answer -- about 20 seconds. Chat templates
+/// carry attachments, so every store of the settings would wait that long, and the plugins starting
+/// during that time ran out of their budget. The answer is not worth storing anyway: it is stale the
+/// moment it is written.
+/// </remarks>
+[TestFixture]
+public sealed class FileAttachmentSerializationTests
+{
+    private const string FILE_PATH = @"\\10.255.255.1\share\report.pdf";
+
+    [Test]
+    public void AChatTemplateIsStoredWithoutCheckingItsAttachments()
+    {
+        var template = new ChatTemplate
+        {
+            FileAttachments = [new FileAttachment(FileAttachmentType.DOCUMENT, "report.pdf", FILE_PATH, 1024)],
+            ExampleConversation =
+            [
+                new ContentBlock
+                {
+                    ContentType = ContentType.TEXT,
+                    Role = ChatRole.USER,
+                    Content = new ContentText
+                    {
+                        Text = "Summarize the report.",
+                        FileAttachments = [new FileAttachmentImage("chart.png", @"\\10.255.255.1\share\chart.png", 2048)],
+                    },
+                },
+            ],
+        };
+
+        var json = JsonSerializer.Serialize(template, SettingsManager.JSON_OPTIONS);
+
+        Assert.Multiple(() =>
+        {
+            Assert.That(json, Does.Contain(FILE_PATH.Replace(@"\", @"\\")), "The attachment has to reach the JSON, or this test checks nothing.");
+            Assert.That(json, Does.Contain("chart.png"), "The attachment of the example conversation has to reach the JSON, or this test checks nothing.");
+            Assert.That(json, Does.Not.Contain("\"Exists\""));
+        });
+    }
+
+    [Test]
+    public void AnAttachmentStoredWithTheFormerFieldStillLoads()
+    {
+        const string LEGACY_JSON = """
+                                   {
+                                     "$type": "file",
+                                     "Type": "DOCUMENT",
+                                     "FileName": "report.pdf",
+                                     "FilePath": "/tmp/report.pdf",
+                                     "FileSizeBytes": 1024,
+                                     "Exists": true
+                                   }
+                                   """;
+
+        var read = JsonSerializer.Deserialize<FileAttachment>(LEGACY_JSON, SettingsManager.JSON_OPTIONS)!;
+
+        Assert.Multiple(() =>
+        {
+            Assert.That(read.FileName, Is.EqualTo("report.pdf"));
+            Assert.That(read.FilePath, Is.EqualTo("/tmp/report.pdf"));
+            Assert.That(read.FileSizeBytes, Is.EqualTo(1024));
+        });
+    }
+}