61 lines
1.8 KiB
Dart
61 lines
1.8 KiB
Dart
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import 'dart:async';
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import 'package:angel_framework/angel_framework.dart';
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import 'package:intl/intl.dart';
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final DateFormat _fmt = new DateFormat('EEE, d MMM yyyy HH:mm:ss');
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/// Formats a date (converted to UTC), ex: `Sun, 03 May 2015 23:02:37 GMT`.
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String _formatDateForHttp(DateTime dt) => _fmt.format(dt.toUtc()) + ' GMT';
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class ResponseCache {
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final List<Pattern> patterns = [];
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final Duration timeout;
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final Map<String, _CachedResponse> _cache = {};
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ResponseCache({this.timeout});
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Future<bool> handleRequest(RequestContext req, ResponseContext res) async {
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var now = new DateTime.now().toUtc();
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// Check if there is a cache entry.
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for (var pattern in patterns) {
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if (pattern.allMatches(req.uri.path).isNotEmpty && _cache.containsKey(req.uri.path)) {
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var response = _cache[req.uri.path];
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// Only send a cached response if it is valid.
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if (timeout == null || now.difference(response.timestamp) >= timeout) {
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// TODO: If-Last-Modified
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break;
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}
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}
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}
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return true;
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}
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Future<bool> responseFinalizer(RequestContext req, ResponseContext res) async {
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var now = new DateTime.now().toUtc();
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}
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void setCachedHeaders(
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DateTime modified, RequestContext req, ResponseContext res) {
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var privacy = 'public';
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res.headers
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..['cache-control'] = '$privacy, max-age=${timeout?.inSeconds ?? 0}'
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..['last-modified'] = _formatDateForHttp(modified);
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if (timeout != null) {
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var expiry = new DateTime.now().add(timeout);
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res.headers['expires'] = _formatDateForHttp(expiry);
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}
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}
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}
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class _CachedResponse {
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final Map<String, String> headers;
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final List<int> body;
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final DateTime timestamp;
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_CachedResponse({this.headers, this.body, this.timestamp});
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}
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