share the same cache between 2 nodejs script

[kenpeter]

I set a cache key and store a value in one nodejs script. How do I use the same key and access the value in another nodejs script? Right now, it will say key_not_found in another script.

[mpneuried]

Thats not possible.
The usecase of node-cache is a cache within one running node process.
You can compare it to a advanced JavaScript object.

It's a planned feature to define a storage provider like process memory, a file or a external server solution.

But for now I recommend using a memcached or redis server that's saving your data.

[CalebEverett]

Would there be any security or performance issues with putting a cache instance on app.locals in an express app?

[mpneuried]

@CalebEverett node-cache for itself has no security built in.
Putting the node-cache to the app.locals of express is a possible solution.
I don't know any security issues of app.locals, but i recommend to asking this question directly to express.

[ffflabs]

What happens if you run nodecache in an app running in cluster mode, say, like in pm2? Does this mean that each thread will have its own cache?

[mpneuried]

@amenadiel Cluster mode or event pm2 cluster ist currently not development target and is not tested yet. Fell free to check it and tell me the results or send me a PR ;-)

[cjaoude]

How to access the same cache in a different module? Seems pointless to have a cache just for one file. (same app) Tnx

[erdii]

@cjaoude you write one singleton module that exports a cache instance and import that one instance everywhere you want to use it.

Example:

./src/cache.js:

const NodeCache = require("nodecache");

module.exports = new NodeCache(/* your nodecache settings here */);

./src/a.js

const cacheSingleton = require("./cache.js");

// cacheSingleton is the same cache instance everywhere inside your app
// as long it runs inside the same node.js process

./src/b.js

const cacheSingleton = require("./cache.js");

// cacheSingleton is the same cache instance everywhere inside your app
// as long it runs inside the same node.js process

This is not specific to NodeCache but more how the node.js module system works. Read more at: https://nodejs.org/dist/latest-v10.x/docs/api/modules.html

[cjaoude]

I see, thanks, that makes sense. @erdii