Rename file to match type

src/SourceBuild/content/eng/tools/tasks/Microsoft.DotNet.SourceBuild.Tasks.SdkArchiveDiff/GetClosestArchive.cs

@@ -0,0 +1,94 @@
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+
+using System;
+using System.IO;
+using System.Net.Http;
+using System.Threading;
+using System.Threading.Tasks;
+using Microsoft.Build.Framework;
+
+public abstract class GetClosestArchive : Microsoft.Build.Utilities.Task, ICancelableTask
+{
+    [Required]
+    public required string BuiltArchivePath { get; init; }
+
+    [Output]
+    public string ClosestOfficialArchivePath { get; set; } = "";
+
+    private string? _builtVersion;
+    protected string BuiltVersion
+    {
+        get => _builtVersion ?? throw new InvalidOperationException();
+        private set => _builtVersion = value;
+    }
+
+    private string? _builtRid;
+    protected string BuiltRid
+    {
+        get => _builtRid ?? throw new InvalidOperationException();
+        private set => _builtRid = value;
+    }
+
+    private string? _archiveExtension;
+    protected string ArchiveExtension
+    {
+        get => _archiveExtension ?? throw new InvalidOperationException();
+        private set => _archiveExtension = value;
+    }
+
+    /// <summary>
+    /// The name of the package to find the closest official archive for. For example, "dotnet-sdk" or "aspnetcore-runtime".
+    /// </summary>
+    protected abstract string ArchiveName { get; }
+
+    private CancellationTokenSource _cancellationTokenSource = new();
+    protected CancellationToken CancellationToken => _cancellationTokenSource.Token;
+    public void Cancel()
+    {
+        _cancellationTokenSource.Cancel();
+    }
+
+    /// <summary>
+    /// Get the URL of the latest official archive for the given version string and RID.
+    /// </summary>
+    public abstract Task<string?> GetLatestOfficialArchiveUrl();
+
+    public abstract Task<string?> GetClosestOfficialArchiveVersion();
+
+    public override bool Execute()
+    {
+        return Task.Run(ExecuteAsync).Result;
+    }
+
+    public async Task<bool> ExecuteAsync()
+    {
+        CancellationToken.ThrowIfCancellationRequested();
+        var filename = Path.GetFileName(BuiltArchivePath);
+        (BuiltVersion, BuiltRid, ArchiveExtension) = Archive.GetInfoFromFileName(filename, ArchiveName);
+        Log.LogMessage($"Finding closest official archive for '{ArchiveName}' version '{BuiltVersion}' RID '{BuiltRid}'");
+
+        string? downloadUrl = await GetLatestOfficialArchiveUrl();
+        if (downloadUrl == null)
+        {
+            Log.LogError($"Failed to find a download URL for '{ArchiveName}' version '{BuiltVersion}' RID '{BuiltRid}'");
+            return false;
+        }
+
+        HttpClient client = new HttpClient();
+
+        Log.LogMessage(MessageImportance.High, $"Downloading {downloadUrl}");
+        HttpResponseMessage packageResponse = await client.GetAsync(downloadUrl, CancellationToken);
+
+        var packageUriPath = packageResponse.RequestMessage!.RequestUri!.LocalPath;
+
+        ClosestOfficialArchivePath = Path.Combine(Path.GetTempPath(), Path.GetRandomFileName() + $".{ArchiveName}-{BuiltVersion}-{BuiltRid}.closest.{ArchiveExtension}");
+        Log.LogMessage($"Copying {packageUriPath} to {ClosestOfficialArchivePath}");
+        using (var file = File.Create(ClosestOfficialArchivePath))
+        {
+            await packageResponse.Content.CopyToAsync(file, CancellationToken);
+        }
+
+        return true;
+    }
+}