Simple API-caching middleware for Express/Node.
Based on v0.11.2, official production version moving to v1.x while work begins on v2.x. This is long overdue, as apicache has been used successfully in production for years around the world.
[multiple] res.write(str) + res.end()
support through a content accumulator. This has been confirmed working with the existing Buffer concept.Object.assign()
(available in Node v4.0+) to store clean copy. Bring on the compressed API requests!Moved header injection of apicache-store
and apicache-version
from before cache-injection to response-building from cache. This allows middleware interceptors to detect the presence of apicache headers only when being built from cache (otherwise they are present regardless).
Adds cache-control max-age header injection
console.log
output when .options({ debug: true })
is explicitly set (backwards compatibility). New [and preferred] method to enable debugging/output of apicache is through DEBUG environment variable.$ export DEBUG=apicache
$ npm run test
$ npm run test:watch
Cheers, and thanks for everyone's contributions, issue tracking, requests, etc. I've been overseas and busy as hell... trying to play catch up on my libs now!
~ Kevin
v0.0.12
An ultra-simplified API/JSON response caching middleware for Express/Node using plain-english durations.
Because caching of simple data/responses should ALSO be simple.
This day and age, with less and less heavy lifting done on the server, the most common thing we find ourselves doing is letting the server power the API. Whether the data is stored in Mongo, SQL, CouchDB, or whatever - you get a request, you fetch the data, and you return the data. Sometimes these fetches are costly and you want to cache the response so the next hit doesn't hammer your server. This is why caching exists.
The problem is, with so many cache options, people are still left to fend for themselves when it comes to implementation. It often boils down to a manual process similar to the following:
You're still left wrapping the content of each request with this cache-checking mechanism.
Now it can be as simple as telling the request that you want to use a cache, and for how long results should be cached (in plain English, not milliseconds, because who really wants to calculate that each time?).
npm install apicache
apicache.clear([target])
- clears cache target (key or group), or entire cache if no value passed, returns new index.apicache.getIndex()
- returns current cache index [of keys]apicache.middleware([duration])
- the actual middleware that will be used in your routes. duration
is in the following format "[length] [unit]", as in "10 minutes"
or "1 day"
.apicache.options([options])
- getter/setter for options. If used as a setter, this function is chainable, allowing you to do things such as... say... return the middleware.{
debug: false|true, // if true, enables console output
defaultDuration: 3600000, // should be a number (in ms), defaults to 1 hour
enabled: true|false, // if false, turns off caching globally (useful on dev)
}
To use, simply inject the middleware (example: apicache('5 minutes')
) into your routes. Everything else is automagic.
var apicache = require('apicache').options({ debug: true }).middleware;
...
// an example route
app.get('/api/v1/myroute', apicache('5 minutes'), function(req, res, next) {
// do some work... this will only occur once per 5 minutes
res.send({ foo: bar });
});
Oftentimes it benefits us to group cache entries, for example, by collection (in an API). This
would enable us to clear all cached "post" requests if we updated something in the "post" collection
for instance. Adding a simple req.apicacheGroup = [somevalue];
to your route enables this. See example below:
var apicache = require('apicache');
var cache = Apicache.middleware;
// GET collection/id
app.get('/api/:collection/:id?', cache('1 hour'), function(req, res, next) {
req.apicacheGroup = req.params.collection;
// do some work
res.send({ foo: 'bar' });
});
// POST collection/id
app.post('/api/:collection/:id?', function(req, res, next) {
// update model
apicache.clear(req.params.collection);
res.send(200);
});
Additionally, you could add manual cache control to the previous project with routes such as these:
// GET apicache index (for the curious)
app.get('/api/cache/index', function(req, res, next) {
res.send(apicache.getIndex());
});
// GET apicache index (for the curious)
app.get('/api/cache/clear/:key?', function(req, res, next) {
res.send(200, ApiCache.clear(req.params.key || req.query.key));
});
When sharing GET
routes between admin and public sites, you'll likely want the
routes to be cached from your public client, but NOT cached when from the admin client. This
is achieved by sending a "x-apicache-bypass": true
header along with the requst from the admin.
The presence of this header flag will bypass the cache, ensuring you aren't looking at stale data.
apicache
is currently an in-memory cache, built upon memory-cache. It may later be expanded to allow other cache-layers.application/json
. There's a reason it's called apicache
.