Add manifest feed parsing for SDK/JDK download resolution (move from android-platform-support)

[rmarinho]

Summary

Add manifest feed parsing to Xamarin.Android.Tools.AndroidSdk so that consumers can resolve SDK/JDK download URLs and checksums from the Xamarin Android Manifest Feed and Google's repository without hardcoding URLs.

Background

The android-platform-support (internal) repository has XamarinRepository and GoogleV2Repository classes that parse:

• Xamarin Android Manifest Feed (https://aka.ms/AndroidManifestFeed/d{version}) — JDK archives, platform-tools, command-line tools, emulator with per-platform/architecture URLs and SHA-1 checksums
• Google SDK Repository (https://dl.google.com/android/repository/repository2-3.xml) — SDK platforms, build-tools, system images, add-ons with SHA-1 checksums

It also includes LocalManifestProvider for offline/CI manifest caching.

This is a prerequisite for the JDK installation (#270) and SDK bootstrap (#271) features — both need manifest feed parsing to resolve download URLs and verify checksums.

Proposed API Surface

• ManifestFeed.LoadAsync(feedUrl) — download and parse a manifest feed
• ManifestFeed.ResolvePackage(packageId, os, arch) — get download URL + SHA-1 for a specific package
• ManifestFeed.GetJdkVersions() — list available JDK versions with download info
• ManifestFeed.Cache(localPath) — cache manifest for offline use

Key Requirements

• No hardcoded download URLs — all URLs come from manifest feeds
• SHA-1 checksum verification — every download must be verified against manifest checksums
• Manifest caching — support offline/CI scenarios with cached manifests
• Cross-platform — resolve correct URLs for Windows/macOS/Linux and x64/aarch64

Consumer

• MAUI DevTools CLI — see MAUI DevTools Spec PR
• JDK installation (Add JDK installation support (move from android-platform-support) #270) and SDK bootstrap (Add SDK bootstrap and sdkmanager wrapper (move from android-platform-support) #271) depend on this

Related

• MAUI DevTools spec §6.8.1: Manifest-Driven Downloads & Checksum Verification
• Add JDK installation support (move from android-platform-support) #270 (JDK installation)
• Add SDK bootstrap and sdkmanager wrapper (move from android-platform-support) #271 (SDK bootstrap)

[rmarinho]

Priority Note

This issue is a critical prerequisite for:

• Add JDK installation support (move from android-platform-support) #270 (JDK installation) — needs manifest to resolve JDK download URLs
• Add SDK bootstrap and sdkmanager wrapper (move from android-platform-support) #271 (SDK bootstrap) — needs manifest to resolve cmdline-tools download URLs

Current state in MAUI DevTools work

I've implemented sdkmanager/avdmanager/adb/emulator wrappers (see #277, #279, #278), but they all assume the tools already exist. Without manifest feed parsing, we cannot:

1. Bootstrap an SDK from scratch (download cmdline-tools)
2. Install JDK automatically (download OpenJDK)
3. Verify downloads with SHA-1 checksums

Reference implementation

The android-platform-support repo has working manifest parsing:

• XamarinRepository — parses Xamarin Android Manifest Feed
• GoogleV2Repository — parses Google SDK repository XML
• LocalManifestProvider — caching for offline/CI

Suggested implementation order

1. This issue (Add manifest feed parsing for SDK/JDK download resolution (move from android-platform-support) #273) — manifest feed parsing
2. Add SDK bootstrap and sdkmanager wrapper (move from android-platform-support) #271 — complete SDK bootstrap using manifest
3. Add JDK installation support (move from android-platform-support) #270 — JDK installation using manifest
4. Add SDK license acceptance support (move from android-platform-support) #272 — complete license management

Would be happy to help implement this if there's alignment on the approach.

[rmarinho]

Implementation Update

I've implemented the manifest feed parsing as part of the MAUI DevTools consolidation work. Here's what's been added:

New Classes in Xamarin.Android.Tools.AndroidSdk

ManifestFeed/

• AndroidManifestFeedParser - Downloads and parses Xamarin manifest feed XML
• ManifestDownloader - Downloads archives with SHA-1 verification
• SdkBootstrapper - Bootstrap SDK by downloading cmdline-tools from manifest
• JdkInstaller - Install JDK from manifest with version selection

Models:

• ManifestArchive - Archive with URL, SHA-1, OS/arch targeting
• ManifestPackage - SDK packages (cmdline-tools, platform-tools, etc.)
• JdkManifestPackage - JDK packages with vendor info
• AndroidManifest - Parsed manifest result

API Surface

// Parse manifest (with optional caching for offline use)
var parser = new AndroidManifestFeedParser(httpClient, cacheDirectory);
var manifest = await parser.LoadAsync();

// Get cmdline-tools for current system
var archive = manifest.CmdlineTools.First().GetBestArchiveForCurrentSystem();
// archive.Url = download URL
// archive.Checksum = SHA-1 for verification

// Bootstrap SDK (download cmdline-tools)
var bootstrapper = new SdkBootstrapper();
await bootstrapper.BootstrapAsync(""/path/to/sdk"");

// Install JDK
var installer = new JdkInstaller();
var jdks = await installer.DiscoverAsync();  // List available JDKs
var result = await installer.InstallAsync(17, ""/path/to/jdk"");  // Install JDK 17

Features Implemented

✅ Download and parse Xamarin manifest feed (https://aka.ms/AndroidManifestFeed/d{version})
✅ Manifest caching for offline/CI scenarios
✅ Per-platform/architecture archive resolution
✅ SHA-1 checksum verification before extraction
✅ JDK version discovery and installation
✅ SDK bootstrap (cmdline-tools download)

Not Yet Implemented

❌ Google SDK repository parsing (repository2-3.xml) - lower priority since Xamarin manifest has what we need
❌ License text retrieval API

This implementation is in a local branch. Would be happy to create a PR if the approach looks good.