Offset and meta user the cache key will posts

// Create broker
const broker = new ServiceBroker({
cacher: "Memory"
});

// Create a service
broker.createService({
name: "users",
actions: {
list: {
// Enable caching to this action
cache: true,
handler(ctx) {
this.logger.info("Handler called!");
return [
{ id: 1, name: "John" },
{ id: 2, name: "Jane" }
]
}
}
}
});

The syntax of key is:

The params object can contain properties that are not relevant for the cache key. Also, it can cause performance

issues if the key is too long. Therefore it is recommended to set an object for cacheproperty which contains a list of

name: "posts",

actions: {

handler(ctx) {

concatenated params in the key with maxParamsLengthcacher option. When the key is longer than the configured

limit value, the cacher calculates a hash (SHA256) from the full key and adds it to the end of the key.

Generate a limited-length key

Conditional caching allows to bypass the cached response and execute an action in order to obtain “fresh” data. To bypass the cache set ctx.meta.$cache to falsebefore calling an action.

Example of turning off the caching for the greeter.hello action

To overwrite the built-in cacher key generator, set your own function as keygenin cacher options.

}

When you create a new model in your service, you have to clear the old cached model entries.

Example to clean the cache inside actions

Example

module.exports = {
name: "users",
actions: {
create(ctx) {
// Create new user entity
const user = new User(ctx.params);

cleanCache() {
// Broadcast the event, so all service instances receive it (including this instance).

this.broker.broadcast("cache.clean.users");
}
}

To make it easier, create a CacheCleanermixin and define in the dependent services schema.

cache.cleaner.mixin.js

if (this.broker.cacher) {

this.logger.debug(`Clear local '${this.name}' cache`);

events

Cache locking

Moleculer also supports cache locking feature. For detailed info .

Disable Lock

Example for Redis cacher with redlock library

const broker = new ServiceBroker({

prefix: "MOL",

// the max number of times Redlock will attempt
// to lock a resource before erroring
retryCount: 10,

// the time in ms between attempts
retryDelay: 200, // time in ms

Enable memory cacher

Options

instead of a Boolean.

Custom clone function with JSON parse & stringify

Enable LRU cacher

Redis cacher

RedisCacher is a built-in based distributed cache module. It uses library.

With options

With MessagePack serializer
You can define a serializer for Redis Cacher. By default, it uses the JSON serializer.

host: "my-redis"
}
}
}

nodes: [
{ port: 6380, host: "127.0.0.1" },
{ port: 6381, host: "127.0.0.1" },
{ port: 6382, host: "127.0.0.1" }
],

});

Options

implement the get, set, del and clean methods.

Create custom cacher