Nodejs：用redis做消息（任务）队列的包——redis-as-queue

Nodejs：用redis做消息（任务）队列的包——redis-as-queue

较之于其它包有一个功能点不一样，就是分 Normal Queue 和 Unique Queue。Normal Queue 就是一个普通的先进先出队列，而 Unique Queue 就是一个唯一的队列，当我们往 Unique Queue 中插入一个已有的消息时，你可以自主选择是更新这个消息到队尾还是不做任何事情。

包名叫 redis-as-queue，仓库地址在：https://github.com/XadillaX/node-redis-as-queue，求 star，求 follow。

所以安装只需要：

$ npm install redis-as-queue

最后为了凑字数帖上流氓的 README：

Usage

There are two kinds of queue - normal queue and unique queue.

Each value in unique queue is unique. If a new value that equals any value in the queue, you may choose to update or not.

First you should require this package:

var raq = require("redis-as-queue");

Normal Queue

Create

var normalQueue = new raq.NormalQueue(QUEUE_NAME, [...]);

Note: [...] is the option(s) to connect redis server. Refer to node-redis document.

Eg.

new raq.NormalQueue(QUEUE_NAME, 6379, '127.0.0.1', {});
new raq.NormalQueue(QUEUE_NAME, unix_socket, options);
...

Push

To push a message to your queue, you may use this function:

normalQueue.push("YOUR MESSAGE", function(err) {
    console.log(err);
});

Get

To get message(s) from your redis queue, you may use get function.

Get earlist one message

normalQueue.get(function(err, messages) {
    console.log(err);
    if(messages.length) console.log(messages[0]);
});

Get earlist N message(s)

// This call gets 10 earlist messages
normalQueue.get(10, function(err, messages) {
    console.log(err);
    for(var i = 0; i < messages.length; i++) console.log(messages[i]);
});

Get all message(s)

normalQueue.get(-1, function(err, messages) {
    console.log(err);
    for(var i = 0; i < messages.length; i++) console.log(messages[i]);
});

Remove

To remove message(s) from your redis queue, you may use removeAmount function.

Remove earlist one message

normalQueue.removeAmount(function(err) {
    console.log(err);
});

Remove earlist N message(s)

normalQueue.removeAmount(5, function(err) {
    console.log(err);
});

Remove all the message(s)

normalQueue.removeAmount(-1, function(err) {
    console.log(err);
});

Length

Get the length of current queue.

normalQueue.length(function(err, len) {
    console.log(len);
});

Unique Queue

Each message in unique queue is unique.

Create

var uniqueQueue = new raq.UniqueQueue(QUEUE_NAME, [...]);

Note: [...] is the option(s) to connect redis server. Refer to node-redis document.

Eg.

new raq.UniqueQueue(QUEUE_NAME, 6379, '127.0.0.1', {});
new raq.UniqueQueue(QUEUE_NAME, unix_socket, options);
...

Push

Push a message to the queue.

Need update

This call will check if your message is existing. If existing, it will move the previous message to the end of queue. Otherwise, your message will be pushed at the end of queue.

uniqueQueue.push("YOUR_MESSAGE", true, function(err) {
    console.log(err);
});

Do not update

This call will check if your message is existing. If existing, it won’t do anything. Otherwise, your message will be pushed at the end of queue.

uniqueQueue.push("YOUR_MESSAGE", function(err) {
    console.log(err);
});
// or you can do this
uniqueQueue.push(“YOUR_MESSAGE”, false, function(err) {
console.log(err);
});

Get

Get first message

uniqueQueue.get(function(err, messages) {
    console.log(err);
    if(messages.length) {
        console.log(messages[0].message);
        console.log(messages[0].updatedAt);
    }
});

Get first N message(s)

uniqueQueue.get(3, function(err, messages) {
    console.log(err);
    for(var i = 0; i < messages.length; i++) {
        console.log(messages[i].message);
        console.log(messages[i].updatedAt);
    }
});

Get all the message(s)

uniqueQueue.get(-1, function(err, messages) {
    console.log(err);
    for(var i = 0; i < messages.length; i++) {
        console.log(messages[i].message);
        console.log(messages[i].updatedAt);
    }
});

Remove Amount

Refer to remove section in Normal Queue.

Remove Messages

Remove one or more certain message(s) in the queue.

uniqueQueue.get(10, function(err, messages) {
    for(var i = 0; i < 5; i++) messages.shift();
// Remove Messages
uniqueQueue.removeMessages(messages, function(err, removeCount, notRemovedMessages) {
    console.log(err);
    console.log(removeCount);
    for(var i = 0; i &lt; notRemovedMessages.length; i++) console.log(notRemovedMessages[i].message);
});
});

Length

Refer to length section in Normal Queue.

Common Functions

Delete Queue

Delete this queue key and values in redis.

uniqueQueue.deleteQueue(function() {});
normalQueue.deleteQueue(function() {});

Destroy Queue Object

Let the queue object disconnect from redis server and let this instance can’t do any other thing any more.

uniqueQueue.destroy();
normalQueue.destroy();