redis-expiry

Use redis to expire your keys and handling the value

📋 Features

• Schedule the expiration of your keys
• Handling your keys and values
• CRUD your scheduler + rescheduling
• Save multiple values in a single key
• Retrieve your value when the key expire
• Add cron task
• Retrieve/Search by regexp

☁️ Installation

$ npm install redis-expiry

⚙️ Examples

const Redis = require("redis");
const redisExpiry = require("redis-expiry");

const redisSetter = Redis.createClient(process.env.REDIS_URL);
const redisGetter = Redis.createClient(process.env.REDIS_URL);

const rexp = redisExpiry(redisSetter, redisGetter);

rexp.set("myKeyByTimeout", "myValue").timeout(60000); // key will be expire in 60sec

const expireDate = new Date();
expireDate.setSeconds(expireDate.getSeconds() + 60);
rexp.set("myKeyByDate", "myValue").at(expireDate); // key will be expire in 60sec

rexp.set("myKeyByCron", "myValue").cron("*/30 * * * * *"); // key will be expire every 30sec

rexp.on(/myKeyBy(.)/, (value, key) => { // event will always be scheduled if the application restart
  console.log("Value returned", value, "From key", key);
});

📝 Usage

Initialization

Create a new instance :

const Redis = require("redis");
const redisExpiry = require("redis-expiry");

const redisSetter = Redis.createClient(process.env.REDIS_URL);
const redisGetter = Redis.createClient(process.env.REDIS_URL);

const rexp = redisExpiry(redisSetter, redisGetter);

The code bellow is deprecated since v1.0.4

const rexp = redisExpiry(redisSetter, process.env.REDIS_URL);

Information

⚠ If your application is shutdown and one of your keys expire, redis-expiry will detect them ⚠
⚠ Then when your application will be operationnal, the event rexp.on("myKey", callback) will be called⚠

Schedule a new scheduler

Before choosing the type of expiration, you have to set the key/value:

rexp.set("myKey", "myValue")...

rexp.set(...).infinit();
A simple redis set:

await rexp.set("myKeyByInfinit", "myValue").infinit();

myKeyByInfinit will never expired.

rexp.set(...).at(date);
Schedule from a date:

const currentDate = new Date();
currentDate.setSeconds(currentDate.getSeconds() + 30);
await rexp.set("myKeyByAt", "myValue").at(currentDate);

myKeyByAt will expire in 30 seconds.

rexp.set(...).timeout(integer);
Schedule from a timeout:

await rexp.set("myKeyByTimeout", "myValue").timeout(60000);

myKeyByTimeout will expire in 60 seconds.

rexp.set(...).now();
Schedule from now:

await rexp.set("myKeyByNow", "myValue").now();

myKeyByNow will expire in few milliseconds.

rexp.set(...).cron();
Schedule from cron:

await rexp.set("myKeyByCron", "myValue").cron("*/4 * * * * *", cronOption);

myKeyByCron will expire in the next multiple of 4 seconds.

⚠ after expiration the event is rescheduled. To stop the cron, check "Adding event handler" part bellow⚠

cronOption is optional, check the link bellow to know more.

More information: https://www.npmjs.com/package/cron-parser

Adding event handler

The handler will be call every time a specified key expires:

rexp.on("myKeyByTimeout", (value, key) => {
  // value === "myValue"
}, {
  maxConcurrent: 1 // Synchro event
});

To stop the cron task execute stop parameter:

rexp.on("myKeyByTimeout", (value, key, stop) => {
  stop(); // stop cron task
});

Using regexp :

rexp.on(/myKeyBy(.)/, (value, key, stop) => {
  // value === "myValue"
});

Every myKeyBy* key will be returned

Cancel scheduler

If no value is specified then every keys will be removed:

await rexp.del("myKeyByTimeout");

Remove specific contents by value:

await rexp.del("myKeyByTimeout", "myValue");

By regexp:

await rexp.del(/(.)Timeout/);

By regexp with a value:

await rexp.del(/(.)Timeout/, "myValue");

By guuid:

await rexp.delByGuuid("Dzokijo");

Retrieve scheduler

If no value is specified then every keys will be returned:

const result = await rexp.get("myKeyByTimeout");

Return specific contents by value:

const result = await rexp.get("myKeyByTimeout", "myValue");

By regexp:

await rexp.get(/(.)Timeout/);

By regexp with a value:

await rexp.get(/(.)Timeout/, "myValue");

By guuid:

await rexp.getByGuuid("Dzokijo");

Edit scheduled value

If no value is specified then every keys will be updated:

const result = await rexp.update("myKeyByTimeout")("myNewValue");

Update specific contents by value:

const result = await rexp.update("myKeyByTimeout", "myValue")("myNewValue");

By regexp:

await rexp.update(/(.)Timeout/)("myNewValue");

By regexp with a value:

await rexp.update(/(.)Timeout/, "myValue")("myNewValue");

By guuid:

await rexp.updateByGuuid("Dzokijo")("myNewValue");

Reschedule a scheduler

Reschedule date:

const currentDate = new Date();
currentDate.setSeconds(currentDate.getSeconds() + 30);
await rexp.reschedule("myKeyByAt", "myValue").at(currentDate);

Reschedule timeout:

await rexp.reschedule("myKeyByTimeout", "myValue").timeout(60000);

Reschedule now:

await rexp.reschedule("myKeyByNow", "myValue").now();

Reschedule cron:

await rexp.reschedule("myKeyByCron", "myValue").cron("*/4 * * * * *");

Reschedule all contents :

await rexp.reschedule("myKeyByTimeout").timeout(30000);

By regexp:

await rexp.reschedule(/(.)Timeout/).timeout(30000);

By regexp with a value:

await rexp.reschedule(/(.)Timeout/, "myValue").timeout(30000);

Every contents is rescheduled with a timeout at 30 secs

By guuid:

await rexp.rescheduleByGuuid("Dzokijo").timeout(30000);

Chainable API
Update value with andUpdateValue function :

await rexp.rescheduleByGuuid("Dzokijo").andUpdateValue("myNewValue").timeout(30000);

❓️ Testing

Clone the repo and run from the project root:

$ npm install
$ npm test