When I wrote this library I used Mongo at work and needed a good caching solution. I no longer use Mongo, and so supporting this library has become a hassle.
If you would like to take over maintaining this project, please open an issue. Thank you!
A Mongoose caching module that works exactly how you would expect it to, with the latest version of Mongoose.
Important:
If you are using Mongoose 4.x or below, you need to use version 4.0.1 of this library.
his is due to Mongoose 5.x no longer having a custom Promise solution(which previous
version of this library relied upon). - https://github.com/Automattic/mongoose/issues/2917
var mongoose = require('mongoose');
var cachegoose = require('cachegoose');
cachegoose(mongoose, {
engine: 'redis', /* If you don't specify the redis engine, */
port: 6379, /* the query results will be cached in memory. */
host: 'localhost'
});
Record
.find({ some_condition: true })
.cache(30) // The number of seconds to cache the query. Defaults to 60 seconds.
.exec(function(err, records) {
...
});
Record
.aggregate()
.group({ total: { $sum: '$some_field' } })
.cache(0) // Explicitly passing in 0 will cache the results indefinitely.
.exec(function(err, aggResults) {
...
});You can also pass a custom key into the .cache() method, which you can then use later to clear the cached content.
var mongoose = require('mongoose');
var cachegoose = require('cachegoose');
cachegoose(mongoose, {
engine: 'redis',
port: 6379,
host: 'localhost'
});
var userId = '1234567890';
Children
.find({ parentId: userId })
.cache(0, userId + '-children') /* Will create a redis entry */
.exec(function(err, records) { /* with the key '1234567890-children' */
...
});
ChildrenSchema.post('save', function(child) {
// Clear the parent's cache, since a new child has been added.
cachegoose.clearCache(child.parentId + '-children');
});Insert .cache() into the queries you want to cache, and they will be cached. Works with select, lean, sort, and anything else that will modify the results of a query.
If you want to clear the cache for a specific query, you must specify the cache key yourself:
function getChildrenByParentId(parentId, cb) {
Children
.find({ parentId })
.cache(0, `${parentId}_children`)
.exec(cb);
}
function clearChildrenByParentIdCache(parentId, cb) {
cachegoose.clearCache(`${parentId}_children`, cb);
}If you call cachegoose.clearCache(null, cb) without passing a cache key as the first parameter, the entire cache will be cleared for all queries.
When a document is returned from the cache, cachegoose will hydrate it, which initializes it's virtuals/methods. Hydrating a populated document will discard any populated fields (see Automattic/mongoose#4727). To cache populated documents without losing child documents, you must use .lean(), however if you do this you will not be able to use any virtuals/methods (it will be a plain object).
npm test