angel_cache 2.0.1

  • README.md
  • CHANGELOG.md
  • Example
  • Installing
  • Versions
  • 57

cache

Pub build status

Support for server-side caching in Angel.

CacheService

A Service class that caches data from one service, storing it in another. An imaginable use case is storing results from MongoDB or another database in MemcacheD/Redis.

cacheSerializationResults

A middleware that enables the caching of response serialization.

This can improve the performance of sending objects that are complex to serialize. You can pass a [shouldCache] callback to determine which values should be cached.

main() async {
    var app = new Angel()..lazyParseBodies = true;
    
    app.use(
      '/api/todos',
      new CacheService(
        database: new AnonymousService(
          index: ([params]) {
            print('Fetched directly from the underlying service at ${new DateTime.now()}!');
            return ['foo', 'bar', 'baz'];
          },
          read: (id, [params]) {
            return {id: '$id at ${new DateTime.now()}'};
          }
        ),
      ),
    );
}

ResponseCache

A flexible response cache for Angel.

Use this to improve real and perceived response of Web applications, as well as to memoize expensive responses.

Supports the If-Modified-Since header, as well as storing the contents of response buffers in memory.

To initialize a simple cache:

Future configureServer(Angel app) async {
  // Simple instance.
  var cache = new ResponseCache();
  
  // You can also pass an invalidation timeout.
  var cache = new ResponseCache(timeout: const Duration(days: 2));
  
  // Close the cache when the application closes.
  app.shutdownHooks.add((_) => cache.close());
  
  // Use `patterns` to specify which resources should be cached.
  cache.patterns.addAll([
    'robots.txt',
    new RegExp(r'\.(png|jpg|gif|txt)$'),
    new Glob('public/**/*'),
  ]);
  
  // REQUIRED: The middleware that serves cached responses
  app.use(cache.handleRequest);
  
  // REQUIRED: The response finalizer that saves responses to the cache
  app.responseFinalizers.add(cache.responseFinalizer);
}

Purging the Cache

Call invalidate to remove a resource from a ResponseCache.

Some servers expect a reverse proxy or caching layer to support PURGE requests. If this is your case, make sure to include some sort of validation (maybe IP-based) to ensure no arbitrary attacker can hack your cache:

Future configureServer(Angel app) async {
  app.addRoute('PURGE', '*', (req, res) {
    if (req.ip != '127.0.0.1')
      throw new AngelHttpException.forbidden();
    return cache.purge(req.uri.path);
  });
}

2.0.1

  • Add ignoreQueryAndFragment to ResponseCache.
  • Rename CacheService.ignoreQuery to ignoreParams.

1.0.0

  • First version

example/main.dart

import 'package:angel_cache/angel_cache.dart';
import 'package:angel_framework/angel_framework.dart';
import 'package:glob/glob.dart';

main() async {
  var app = new Angel();

  // Cache a glob
  var cache = new ResponseCache()
    ..patterns.addAll([
      new Glob('/*.txt'),
    ]);

  // Handle `if-modified-since` header, and also send cached content
  app.fallback(cache.handleRequest);

  // A simple handler that returns a different result every time.
  app.get('/date.txt',
      (req, res) => res.write(new DateTime.now().toIso8601String()));

  // Support purging the cache.
  app.addRoute('PURGE', '*', (req, res) {
    if (req.ip != '127.0.0.1') throw new AngelHttpException.forbidden();

    cache.purge(req.uri.path);
    print('Purged ${req.uri.path}');
  });

  // The response finalizer that actually saves the content
  app.responseFinalizers.add(cache.responseFinalizer);

  var http = new AngelHttp(app);
  var server = await http.startServer('127.0.0.1', 3000);
  print('Listening at http://${server.address.address}:${server.port}');
}

Use this package as a library

1. Depend on it

Add this to your package's pubspec.yaml file:


dependencies:
  angel_cache: ^2.0.1

2. Install it

You can install packages from the command line:

with pub:


$ pub get

with Flutter:


$ flutter packages get

Alternatively, your editor might support pub get or flutter packages get. Check the docs for your editor to learn more.

3. Import it

Now in your Dart code, you can use:


import 'package:angel_cache/angel_cache.dart';
  
Version Uploaded Documentation Archive
2.0.1 Nov 10, 2018 Go to the documentation of angel_cache 2.0.1 Download angel_cache 2.0.1 archive
2.0.0 Oct 21, 2018 Go to the documentation of angel_cache 2.0.0 Download angel_cache 2.0.0 archive
1.0.0 May 16, 2018 Go to the documentation of angel_cache 1.0.0 Download angel_cache 1.0.0 archive
Popularity:
Describes how popular the package is relative to other packages. [more]
22
Health:
Code health derived from static analysis. [more]
100
Maintenance:
Reflects how tidy and up-to-date the package is. [more]
80
Overall:
Weighted score of the above. [more]
57
Learn more about scoring.

We analyzed this package on Nov 14, 2018, and provided a score, details, and suggestions below. Analysis was completed with status completed using:

  • Dart: 2.0.0
  • pana: 0.12.6

Platforms

Detected platforms: Flutter, other

Primary library: package:angel_cache/angel_cache.dart with components: io.

Maintenance suggestions

The description is too short. (-20 points)

Add more detail about the package, what it does and what is its target use case. Try to write at least 60 characters.

Dependencies

Package Constraint Resolved Available
Direct dependencies
Dart SDK >=2.0.0-dev <3.0.0
angel_framework ^2.0.0-alpha 2.0.0-alpha.14
collection ^1.0.0 1.14.11
meta ^1.0.0 1.1.6
pool ^1.0.0 1.3.6
Transitive dependencies
angel_container 1.0.0-alpha.12
angel_http_exception 1.0.0+3
angel_model 1.0.0+1
angel_route 3.0.0
async 2.0.8
body_parser 1.1.1
charcode 1.1.2
code_buffer 1.0.1
combinator 1.0.0+3
convert 2.0.2
crypto 2.0.6
dart2_constant 1.0.2+dart2
file 5.0.6
http2 0.1.9
http_parser 3.1.3
http_server 0.9.8+1
intl 0.15.7
logging 0.11.3+2
matcher 0.12.4
merge_map 1.0.1
mime 0.9.6+2
mock_request 1.0.4
path 1.6.2
quiver 2.0.1
source_span 1.4.1
stack_trace 1.9.3
string_scanner 1.0.4
tuple 1.0.2
typed_data 1.1.6
uuid 1.0.3
Dev dependencies
angel_test ^2.0.0-alpha
glob ^1.0.0
http any
test ^1.0.0