Typing for ExportedApi and minimal test

app/lib/package/api_export/exported_api.dart

@@ -1,7 +1,13 @@
+// Copyright (c) 2024, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
 import 'dart:async';
 import 'dart:convert';
 import 'dart:io';
 
+import 'package:_pub_shared/data/advisories_api.dart';
+import 'package:_pub_shared/data/package_api.dart';
 import 'package:clock/clock.dart';
 import 'package:gcloud/storage.dart';
 import 'package:logging/logging.dart';
@@ -43,7 +49,8 @@ final class ExportedApi {
       ExportedPackage._(this, packageName);
 
   /// Interface for writing `/api/package-name-completion-data`
-  ExportedJsonFile get packageNameCompletionData => ExportedJsonFile._(
+  ExportedJsonFile<Map<String, Object?>> get packageNameCompletionData =>
+      ExportedJsonFile<Map<String, Object?>>._(
         this,
         '/api/package-name-completion-data',
         Duration(hours: 8),
@@ -178,7 +185,7 @@ final class ExportedPackage {
 
   ExportedPackage._(this._owner, this._package);
 
-  ExportedJsonFile _suffix(String suffix) => ExportedJsonFile._(
+  ExportedJsonFile<T> _suffix<T>(String suffix) => ExportedJsonFile<T>._(
         _owner,
         '/api/packages/$_package$suffix',
         Duration(minutes: 10),
@@ -187,10 +194,11 @@ final class ExportedPackage {
   /// Interface for writing `/api/packages/<package>`.
   ///
   /// Which contains version listing information.
-  ExportedJsonFile get versions => _suffix('');
+  ExportedJsonFile<PackageData> get versions => _suffix<PackageData>('');
 
   /// Interface for writing `/api/packages/<package>/advisories`.
-  ExportedJsonFile get advisories => _suffix('/advisories');
+  ExportedJsonFile<ListAdvisoriesResponse> get advisories =>
+      _suffix<ListAdvisoriesResponse>('/advisories');
 
   /// Interace for writing `/api/archives/<package>-<version>.tar.gz`.
   ExportedBlob tarball(String version) => ExportedBlob._(
@@ -239,7 +247,7 @@ sealed class ExportedObject {
 ///  * `Content-Type`,
 ///  * `Content-Encoding`, and,
 ///  * `Cache-Control`.
-final class ExportedJsonFile extends ExportedObject {
+final class ExportedJsonFile<T> extends ExportedObject {
   static final _jsonGzip = json.fuse(utf8).fuse(gzip);
   final Duration _maxAge;
 
@@ -256,7 +264,7 @@ final class ExportedJsonFile extends ExportedObject {
   );
 
   /// Write [data] as gzipped JSON in UTF-8 format.
-  Future<void> write(Map<String, Object?> data) async {
+  Future<void> write(T data) async {
     final gzipped = _jsonGzip.encode(data);
     await Future.wait(_owner._prefixes.map((prefix) async {
       await _owner._pool.withResource(() async {

app/test/package/api_export/exported_api_test.dart

@@ -0,0 +1,94 @@
+// Copyright (c) 2024, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+import 'dart:convert';
+import 'dart:io';
+import 'dart:typed_data';
+
+import 'package:_pub_shared/data/package_api.dart';
+import 'package:clock/clock.dart';
+import 'package:gcloud/storage.dart';
+import 'package:googleapis/storage/v1.dart' show DetailedApiRequestError;
+import 'package:pub_dev/package/api_export/exported_api.dart';
+import 'package:pub_dev/shared/storage.dart';
+import 'package:pub_dev/shared/utils.dart';
+import 'package:test/test.dart';
+import '../../shared/test_services.dart';
+
+void main() {
+  testWithFakeTime('ExportedApi', (fakeTime) async {
+    await storageService.createBucket('exported-api');
+    final bucket = storageService.bucket('exported-api');
+
+    /// Read bytes from bucket
+    Future<Uint8List?> readBytes(String path) async {
+      try {
+        return await bucket.readAsBytes(path);
+      } on DetailedApiRequestError catch (e) {
+        if (e.status == 404) return null;
+        rethrow;
+      }
+    }
+
+    /// Read gzipped JSON from bucket
+    Future<Object?> readGzippedJson(String path) async {
+      final bytes = await readBytes(path);
+      if (bytes == null) {
+        return null;
+      }
+      return utf8JsonDecoder.convert(gzip.decode(bytes));
+    }
+
+    final exportedApi = ExportedApi(storageService, bucket);
+
+    // Test that deletion works when bucket is empty
+    await exportedApi.package('retry').delete();
+
+    // Test that GC works when bucket is empty
+    await exportedApi.garbageCollect({});
+
+    final retryPkgData1 = PackageData(
+      name: 'retry',
+      latest: VersionInfo(
+        version: '1.2.3',
+        retracted: false,
+        pubspec: {},
+        archiveUrl: '-',
+        archiveSha256: '-',
+        published: clock.now(),
+      ),
+      versions: [],
+    );
+
+    await exportedApi.package('retry').versions.write(retryPkgData1);
+
+    expect(
+      await readGzippedJson('latest/api/packages/retry'),
+      json.decode(json.encode(retryPkgData1.toJson())),
+    );
+
+    // Check that GC after 10 mins won't delete a package we don't recognize
+    fakeTime.elapseSync(minutes: 10);
+    await exportedApi.garbageCollect({});
+    expect(
+      await readGzippedJson('latest/api/packages/retry'),
+      isNotNull,
+    );
+
+    // Check that GC after 2 days won't delete a package we know
+    fakeTime.elapseSync(days: 2);
+    await exportedApi.garbageCollect({'retry'});
+    expect(
+      await readGzippedJson('latest/api/packages/retry'),
+      isNotNull,
+    );
+
+    // Check retry after 2 days will delete a package we don't know.
+    await exportedApi.garbageCollect({});
+    expect(
+      await readGzippedJson('latest/api/packages/retry'),
+      isNull,
+    );
+  });
+}