WO2020140614A1

WO2020140614A1 - Offline message distribution method, server and storage medium

Info

Publication number: WO2020140614A1
Application number: PCT/CN2019/117333
Authority: WO
Inventors: 詹泽
Original assignee: 平安科技（深圳）有限公司
Priority date: 2019-01-04
Filing date: 2019-11-12
Publication date: 2020-07-09
Also published as: CN109756417B; CN109756417A

Abstract

Disclosed in the present application is an MQTT protocol-based offline message distribution method. The method comprises: receiving a message issued by a first client and storing the message in a message queue; receiving a connection instruction of a second client, and determining an offline time period of the second client; separately determining messages in the offline time period corresponding to the second client to generate an offline message list of the second client; and distributing the messages in the offline message list to the second client. Also disclosed in the present application are a server and a computer storage medium. In using the present application, time complexity and space complexity are reduced, and the offline message distribution efficiency is improved.

Description

Offline message distribution method, server and storage medium

This application is based on the declaration of the Paris Convention and enjoys the priority of the Chinese patent application filed on January 4, 2019, with the application number CN201910007206.X and the name "offline message distribution method, server and storage medium". The entirety of the Chinese patent application The content is incorporated in this application by reference.

Technical field

The present application relates to the field of data processing technology, and in particular to an offline message distribution method, server, and computer-readable storage medium based on the MQTT protocol.

Background technique

As early as 1999, Dr. Andy Stanford-Clark of IBM and Dr. ArlenNipper of Arcom Corporation invented the MQTT (Message Queuing Telemetry Transport) technology. At present, many domestic enterprises widely use MQTT as the protocol for pushing messages between the Android mobile client and the server. Among them, Sohu and Cmstop mobile client all use MQTT as a message push message.

One function of the MQTT protocol is offline message processing. Many MQTT products in the market deal with offline messages differently. Offline messages for open source MQTT server projects such as ActiveMQ, moquette, apolo, etc. are distributed for one client and one offline message list. Regardless of the time complexity or Kongjia complexity, when the number of clients is large and the number of offline messages is large, not only will the server processing performance be degraded, but also a lot of storage space will be wasted.

Summary of the invention

In view of the above, the present application provides an offline message distribution method, server, and computer-readable storage medium based on the MQTT protocol. Its main purpose is to reduce time complexity and space complexity, and improve offline message distribution efficiency.

To achieve the above purpose, the present application provides an offline message distribution method based on the MQTT protocol. The method includes:

S1. Receive the message published by the first client, determine the message queue corresponding to the message according to the attribute information of the message, and save the message in the message queue based on the first preset rule;

S2. Receive the connection instruction of the second client, obtain the online time and the last offline time of the second client, and determine the offline time period;

S3. Determine one or more message queues corresponding to the second client respectively, find the messages of the second client in the offline time period from the one or more message queues respectively, and generate the first The offline message list of the two clients; and

S4. Distribute the messages in the offline message list to the second client based on the second preset rule.

In addition, the present application also provides a server including: a memory and a processor, and the memory stores an offline message distribution program that can run on the processor, and the offline message distribution program is used by the processor During execution, any steps in the offline message distribution method described above can be implemented.

In addition, in order to achieve the above object, the present application also provides a computer-readable storage medium, the computer-readable storage medium includes an offline message distribution program, when the offline message distribution program is executed by the processor, the Any step in the offline message distribution method.

The offline message distribution method, server and computer-readable storage medium proposed in this application receive the message issued by the first client, and save it in the corresponding message queue according to the topic corresponding to the message and according to the first preset rule. When the second client reconnects to the server, the offline time period of the second client and the offline message within the offline time period are determined, and the offline message is distributed to the second client according to the second preset rule. Each topic corresponds to a message list. When multiple second clients reconnect to the server, all offline messages corresponding to a topic are pulled from the same message list, while reducing time and space complexity, and improving offline messages. Distribution efficiency.

BRIEF DESCRIPTION

FIG. 1 is a schematic diagram of a preferred embodiment of the application server;

2 is a schematic diagram of program modules of the offline message distribution program in FIG. 1;

FIG. 3 is a flowchart of a preferred embodiment of the offline message distribution method of the present application.

The implementation, functional characteristics and advantages of the present application will be further described in conjunction with the embodiments and with reference to the drawings.

detailed description

It should be understood that the specific embodiments described herein are only used to explain the present application, and are not used to limit the present application.

This application provides a server. Referring to FIG. 1, it is a schematic diagram of a preferred embodiment of the server of the present application.

The server 1 is applied to a message distribution system based on the MQTT protocol (not shown in the figure). The system includes: a server cluster including a plurality of the server 1 and a first client (not shown in the figure), The second client (not shown in the figure). Wherein, the first client is a message publishing terminal for publishing messages to the server 1; the second client is a message subscribing terminal, and the second client only subscribes to the topic (topic, topic) corresponding to the first client For example, the weather can only receive the message published by the first client. The first client and the second client may be terminal devices with data processing functions such as smart phones, tablet computers, portable computers, and desktop computers.

In other embodiments, the message distribution system further includes: a load balancing device (not shown in the figure).

The load balancing device includes: a first load balancing device (not shown in the figure) and a second load balancing device (not shown in the figure). It should be noted that the first load balancing device and the second load balancing device may be the same load balancing device, or may be different load balancing devices.

The first load balancing device is used to receive the message issued by the first client and distribute the message to each server 1 in the server cluster for storage based on a preset load balancing rule.

The second load balancing device is used to receive the connection instruction issued by the second client, and distribute the connection instruction to each server 1 in the server cluster for processing based on a preset load balancing rule.

Since the messages published by the first client are stored in the central storage, each server can identify all the messages corresponding to each second client and distribute them to the corresponding second client.

The preset load balancing rule is to distribute according to the load of each server 1 in the server cluster. For example, it is allocated to the server with the least real-time load for processing.

In this embodiment, the server 1 may also be a rack server, a blade server, a tower server, or a rack server.

In FIG. 1, the server 1 includes a memory 11, a processor 12, and a network interface 13.

Among them, the memory 11 includes at least one type of readable storage medium, and the readable storage medium includes a flash memory, a hard disk, a multimedia card, a card-type memory (for example, SD or DX memory, etc.), a magnetic memory, a magnetic disk, an optical disk, and the like. In some embodiments, the memory 11 may be an internal storage unit of the server 1, such as the hard disk of the server 1. In other embodiments, the memory 11 may also be an external storage device of the server 1, such as a plug-in hard disk equipped on the server 1, a smart memory card (Smart, Media, Card, SMC), and a secure digital (SD, Digital, SD) ) Card, flash card (Flash Card), etc. Further, the memory 11 may also include both the internal storage unit of the server 1 and the external storage device.

The memory 11 can be used not only to store application software installed on the server 1 and various types of data, such as an offline message distribution program 10, but also to temporarily store data that has been or will be output.

In some embodiments, the processor 12 may be a central processing unit (CPU), controller, microcontroller, microprocessor, or other data processing chip for running the program code or processing stored in the memory 11 Data, for example, offline message distribution program 10, etc.

The network interface 13 may optionally include a standard wired interface and a wireless interface (such as a WI-FI interface), and is generally used to establish a communication connection between the server 1 and other electronic devices. For example, data transmission with the client (not marked in the figure).

FIG. 1 only shows a server 1 having components 11-13. Those skilled in the art can understand that the structure shown in FIG. 1 does not constitute a limitation on the server 1, and may include fewer or more than shown. Components, or some combination of components, or different component arrangements.

Optionally, the server 1 may further include a user interface. The user interface may include a display, an input unit such as a keyboard, and the optional user interface may further include a standard wired interface and a wireless interface.

Optionally, in some embodiments, the display may be an LED display, a liquid crystal display, a touch-sensitive liquid crystal display, an organic light-emitting diode (OLED) touch device, or the like. Among them, the display may also be referred to as a display screen or a display unit, for displaying information processed in the server 1 and for displaying a visual user interface.

In the embodiment of the server 1 shown in FIG. 1, the memory 11 as a computer storage medium stores the program code of the offline message distribution program 10, and when the processor 12 executes the program code of the offline message distribution program 10, the implementation step is: A1 -A4.

A1. Receive the message issued by the first client, determine the message queue corresponding to the message according to the attribute information of the message, and save the message in the message queue based on the first preset rule.

Among them, the first client is the message publishing end.

The attribute information of the message includes information such as the time stamp of the message, the topic (for example, weather) corresponding to the message, and the like. The MQTT protocol stipulates that when sending a message to a server, the message publisher needs to transmit the tipic corresponding to the message, so the server can directly obtain the topic information corresponding to the message.

It should be noted that each topic corresponds to a message queue. In other words, the number of message queues is only related to the topic, and has nothing to do with the number of second clients (message subscribers).

Each message belongs to only one topic, and only clients that subscribe to the topic can receive this type of message. For example, the topic is weather, and the first client is a client that publishes weather messages. Only the second client that subscribes to the topic "weather" can receive weather messages. After the first client publishes a weather message, the server receives the weather message, determines the corresponding topic "weather" according to its attribute information, and saves the message to the message queue corresponding to "weather".

In this embodiment, the "save the message in the message queue according to the first preset rule" includes:

Obtain a time stamp from the attribute information of the message, and according to the order of the time stamp from early to late, sequentially save the message at the head of the message queue corresponding to the message.

Taking the topic "weather" as an example, the attribute information of the message also includes a time stamp of each message. The time stamp is the time when the message was published, that is, the time when the server received the message. After receiving the message, sort the messages according to the order of time, and then find the message queue corresponding to the topic of "weather", and store the message to the head of the message queue in sequence, that is, the message at the head of the message queue is the publication time The latest (newest) message, and the message at the end of the message queue is the oldest (oldest) message.

It should be noted that the effective time (for example, 7 days) of each message is preset, and when the time for saving the message to the message queue exceeds the preset effective time, the message is deleted from the message queue.

A2. Receive the connection instruction of the second client, obtain the online time and the last offline time of the second client, and determine the offline time period.

The second client is a message subscription end, subscribes to one or more topics through the second client, and receives messages corresponding to one or more topics. When the second client performs each offline or online operation, the server can obtain and record the time when each second client is offline or online. The online operation performed by the user through the second client is a signal that triggers the distribution of offline messages.

When the connection instruction of the second client is detected, the time when the current second client issues the connection instruction is taken as the end time of the offline time period, and the latest offline time before the current second client issues the connection instruction as the offline time The start time of the segment determines the offline time period of the second client according to the start time and the end time. For example, the online time this time is a, and the offline time before this time online is b, then the offline time period of the second client is b-a.

For different second clients, the offline time period may be the same or different.

A3. Determine one or more message queues corresponding to the second client respectively, find out the messages of the second client in the offline time period from the one or more message queues respectively, and generate the first The offline message list of the two clients.

Specifically, the "finding messages of the second client in the offline time period from the one or more message queues respectively as offline messages of the second client" includes:

Obtain the first message of a message queue, obtain a time stamp from the attribute information of the first message, and determine whether the time stamp is within the offline time period;

If yes, it is determined that the first message is an offline message, and the next message in the message queue is sequentially obtained and the above steps are repeated;

If not, it is determined that the first message is not an offline message, and it is determined that there is no offline message of the second client in the message queue.

Since the messages in a message queue are sorted in the order of the release time, if the release time of the latest message is not in the offline period, then other messages in the queue must not be in the offline period. If the latest message is an offline message, then go forward in turn to determine whether the second message is within the offline time period. By first judging whether the latest message is an offline message, many redundant judgments can be reduced, thereby saving resources.

Repeat the above steps to obtain offline messages in all message queues of the second client in the offline time period, and generate an offline message list. In the offline message list, the latest offline message is ranked first, and the oldest offline message is ranked next.

In this embodiment, the number of message queues corresponding to the second client is the same as the number of TOPICs subscribed by the second client. Each second client subscribes to N TOPICs, that is, corresponds to N message queues, where N is an integer greater than or equal to 0.

For example, the second client P subscribes to N topics, and sequentially determines the messages of the second client P in the offline time period (ba) from the message queues corresponding to the N topics, that is, the offline messages of the second client P . There may be offline messages of the second client P in the message queue, or there may be no offline messages of the second client P.

It should be noted that the same message queue is common to all second clients subscribing to the topic. Because the online/offline time (ie, offline time period) of different second clients is inconsistent, therefore, different second clients correspond to There may also be differences in the offline message list.

A4. Distribute the messages in the offline message list to the second client based on the second preset rule.

Wherein, the second preset rule includes:

According to the order of the offline messages in the offline message list, the offline messages are sequentially sent to the second client.

For example, for a certain offline message list L, in the offline message list L, the order of each offline message is: m1, m2, m3, ..., m10, where m1 is the latest offline message and m10 is the oldest For offline messages, in the process of distributing offline messages, the latest offline message m1 is distributed first, then the offline message m2 is distributed, and so on.

Preferably, the second preset rule in this embodiment further includes:

When the second client corresponds to multiple offline message lists, the subscription time of the topic corresponding to each offline message list is determined, and the offline messages in each offline message list are distributed in order according to the order of the subscription time from early to late.

When distributing offline messages for a second client, if there are offline messages corresponding to multiple topics that need to be distributed, determine the order of the topics according to the order of the subscription time, and then obtain the offline messages of each topic for distribution.

The server 1 proposed in the above embodiment receives the message published by the first client, saves it to the corresponding message queue according to the topic corresponding to the message according to the first preset rule, and determines the second when the second client reconnects to the server The offline time period of the client and the offline messages in the offline time period distribute the offline message to the second client according to the second preset rule. Each topic corresponds to a message list. When multiple second clients reconnect to the server, all offline messages corresponding to a topic are pulled from the same message list, while reducing time and space complexity, and improving offline messages. Distribution efficiency.

In other embodiments, the "save the message in the message queue according to the first preset rule" in step A1 includes:

When the number of messages in the message queue is the first preset threshold, each time a new message is received, a message at the end of the message queue is removed, and the new message is placed at the head of the message queue.

For example, the maximum capacity of the message queue is set in advance. If there are already 1000 messages in the message queue, the oldest message needs to be deleted every time a new message comes in, and then the new message is saved.

In other embodiments, the "save the message in the message queue according to the first preset rule" also includes:

When the number of messages in the message queue reaches the second preset threshold, generate warning information and send it to a preset terminal, receive an instruction issued by the preset terminal to update the first preset threshold, respond to the instruction and execute The first preset threshold update operation.

For example, the warning value 900 of the capacity of the message queue is preset, and the second preset threshold corresponds to the first preset threshold. When the number of messages in the message queue reaches 900, a warning message is sent to the preset terminal (for example, "the number of messages in the message queue is about to reach the upper limit, please make adjustments in time"). The administrator sends an instruction to adjust the first preset threshold through the preset terminal, and the instruction includes the updated value of the first preset threshold, for example, 1200. This step ensures the integrity of the message.

Optionally, in other embodiments, the offline message distribution program 10 may also be divided into one or more modules, and the one or more modules are stored in the memory 11 and controlled by one or more processors (this implementation The example is executed by the processor 12) to complete this application. The module referred to in this application refers to a series of computer program instruction segments capable of performing specific functions.

For example, referring to FIG. 2, which is a block diagram of the offline message distribution program 10 in FIG. 1, in this embodiment, the offline message distribution program 10 may be divided into a first receiving 110, a second receiving module 120, a query module 130, and The distribution module 140, the functions or operation steps implemented by the modules 110-140 are similar to the above, and will not be described in detail here, for example, for example:

The first receiving module 110 is configured to receive a message published by the first client, determine the message queue corresponding to the message according to the attribute information of the message, and save the message in the message queue based on the first preset rule;

The second receiving module 120 is configured to receive the connection instruction of the second client, obtain the online time and the last offline time of the second client, and determine the offline time period;

The query module 130 is configured to determine one or more message queues corresponding to the second client respectively, and find out the messages of the second client in the offline time period from the one or more message queues, Generate an offline message list of the second client; and

The distribution module 140 is configured to distribute the messages in the offline message list to the second client based on the second preset rule.

This application provides an offline message distribution method based on the MQTT protocol. Referring to FIG. 3, it is a flowchart of a preferred embodiment of an offline message distribution method based on the MQTT protocol of the present application. The method may be executed by a server, and the server may be implemented by software and/or hardware.

In this embodiment, the offline message distribution method based on the MQTT protocol is applied to the server, and the method includes steps S1-S4.

S1. Receive the message published by the first client, determine the message queue corresponding to the message according to the attribute information of the message, and save the message in the message queue based on the first preset rule.

Among them, the first client is the message publishing end.

S2. Receive the connection instruction of the second client, obtain the online time and the last offline time of the second client, and determine the offline time period.

S3. Determine one or more message queues corresponding to the second client respectively, find the messages of the second client in the offline time period from the one or more message queues respectively, and generate the first The offline message list of the two clients.

Wherein, the second preset rule includes:

Preferably, the second preset rule in this embodiment further includes:

The offline message distribution method based on the MQTT protocol proposed in the above embodiment receives the message published by the first client, saves it to the corresponding message queue according to the topic corresponding to the message according to the first preset rule, and waits for the second client to reconnect The server determines the offline time period of the second client and the offline message within the offline time period, and distributes the offline message to the second client according to the second preset rule. Each topic corresponds to a message list. When multiple second clients reconnect to the server, all offline messages corresponding to a topic are pulled from the same message list, while reducing time and space complexity, and improving offline messages. Distribution efficiency.

In other embodiments, the "save the message in the message queue according to the first preset rule" in step S1 includes:

In other embodiments, the "save the message in the message queue according to the first preset rule" in step S1 also includes:

The offline message distribution method based on the MQTT protocol proposed in the above embodiment manages and controls the capacity of messages in each message queue to save storage space while ensuring the integrity of offline messages.

In addition, an embodiment of the present application also provides a computer-readable storage medium, which includes an offline message distribution program 10, and when the offline message distribution program 10 is executed by a processor, the following operations are implemented:

A1. Receive the message published by the first client, determine the message queue corresponding to the message according to the attribute information of the message, and save the message in the message queue based on the first preset rule;

A2. Receive the connection instruction of the second client, obtain the online time and the last offline time of the second client, and determine the offline time period;

A3. Determine one or more message queues corresponding to the second client respectively, find out the messages of the second client in the offline time period from the one or more message queues respectively, and generate the first The offline message list of the two clients; and

The specific implementation of the computer-readable storage medium of the present application is substantially the same as the specific implementation of the offline message distribution method described above, and details are not described herein again.

The sequence numbers of the above embodiments of the present application are for description only, and do not represent the advantages and disadvantages of the embodiments.

It should be noted that in this article, the terms "include", "include" or any other variant thereof are intended to cover non-exclusive inclusion, so that a process, device, article or method including a series of elements includes not only those elements It also includes other elements that are not explicitly listed, or include elements inherent to such processes, devices, objects, or methods. Without more restrictions, the element defined by the sentence "include one..." does not exclude that there are other identical elements in the process, device, article or method that includes the element.

Through the description of the above embodiments, those skilled in the art can clearly understand that the methods in the above embodiments can be implemented by means of software plus a necessary general hardware platform, and of course, can also be implemented by hardware, but in many cases the former is better Implementation. Based on this understanding, the technical solution of the present application can be embodied in the form of a software product in essence or part that contributes to the prior art, and the computer software product is stored in a storage medium (such as ROM/RAM) as described above , Magnetic disk, optical disk), including several instructions to enable a terminal device (which may be a mobile phone, computer, server, or network device, etc.) to perform the method described in each embodiment of the present application.

The above are only preferred embodiments of the present application, and do not limit the patent scope of the present application. Any equivalent structure or equivalent process transformation made by the description and drawings of this application, or directly or indirectly used in other related technical fields The same reason is included in the patent protection scope of this application.

Claims

An offline message distribution method based on the MQTT protocol, applied to a server, characterized in that the method includes:

S1. Receive the message published by the first client, determine the message queue corresponding to the message according to the attribute information of the message, and save the message in the message queue based on the first preset rule;

S2. Receive the connection instruction of the second client, obtain the online time and the last offline time of the second client, and determine the offline time period;

S3. Determine one or more message queues corresponding to the second client respectively, find the messages of the second client in the offline time period from the one or more message queues respectively, and generate the first The offline message list of the two clients; and

S4. Distribute the messages in the offline message list to the second client based on the second preset rule.
The offline message distribution method according to claim 1, wherein the "save the message in the message queue according to the first preset rule" includes: obtaining a time stamp from the attribute information of the message, According to the order of the timestamps from early to late, the messages are sequentially saved at the head of the message queue corresponding to the messages.
The offline message distribution method according to claim 1, wherein the "finding messages of the second client in the offline time period from the one or more message queues as the first "Offline messages of the second client", including:

Obtain the first message of a message queue, obtain a time stamp from the attribute information of the first message, and determine whether the time stamp is within the offline time period;

If yes, it is judged that the first message is an offline message, and the next message in the message queue is sequentially obtained and the judgment step is repeated;

If not, it is determined that the first message is not an offline message, and it is determined that there is no offline message of the second client in the message queue.
The offline message distribution method according to claim 3, wherein the second preset rule includes: according to the order of the offline messages in the offline message list, sequentially sending the offline messages to the second client.
The offline message distribution method according to claim 4, wherein the second preset rule further comprises: when the second client corresponds to a plurality of offline message lists, determining the theme of the topic corresponding to each offline message list Subscription time, according to the order of the subscription time from morning to night, distribute the offline messages in each offline message list in turn.
The offline message distribution method according to claim 3, wherein the "save the message in the message queue according to the first preset rule" includes: when the number of messages in the message queue is the first When the threshold is set, each time a new message is received, a message at the end of the message queue is removed, and the new message is placed at the head of the message queue.
The offline message distribution method according to claim 6, wherein the "save the message in the message queue according to the first preset rule" further includes:

When the number of messages in the message queue reaches a second preset threshold, generate warning information and send it to a preset terminal, and receive an instruction issued by the preset terminal to update the first preset threshold, respond to the instruction and Perform the first preset threshold update operation.
A server, characterized in that the server includes: a memory and a processor, and the memory stores an offline message distribution program that can run on the processor, when the offline message distribution program is executed by the processor , The following steps can be achieved:

A1. Receive the message published by the first client, determine the message queue corresponding to the message according to the attribute information of the message, and save the message in the message queue based on the first preset rule;

A2. Receive the connection instruction of the second client, obtain the online time and the last offline time of the second client, and determine the offline time period;

A3. Determine one or more message queues corresponding to the second client respectively, find out the messages of the second client in the offline time period from the one or more message queues respectively, and generate the first The offline message list of the two clients; and

A4. Distribute the messages in the offline message list to the second client based on the second preset rule.
The server according to claim 8, wherein the "save the message in the message queue according to the first preset rule" includes: obtaining a time stamp from attribute information of the message, according to the In the order of timestamps from early to late, the message is sequentially saved at the head of the message queue corresponding to the message.
The server according to claim 8, wherein the "find messages of the second client in the offline time period from the one or more message queues respectively, as the second client's Offline messages", including:

Obtain the first message of a message queue, obtain a time stamp from the attribute information of the first message, and determine whether the time stamp is within the offline time period;

If yes, it is judged that the first message is an offline message, and the next message in the message queue is sequentially obtained and the judgment step is repeated;

If not, it is determined that the first message is not an offline message, and it is determined that there is no offline message of the second client in the message queue.
The server according to claim 10, wherein the second preset rule includes: according to the order of each offline message in the offline message list, sequentially sending offline messages to the second client.
The server according to claim 11, wherein the second preset rule further comprises: when the second client corresponds to multiple offline message lists, determining the subscription time of the topic corresponding to each offline message list, According to the order of the subscription time from early to late, the offline messages in each offline message list are distributed in sequence.
The server according to claim 10, wherein the "save the message in the message queue according to the first preset rule" includes: when the number of messages in the message queue is the first preset threshold Each time a new message is received, a message at the end of the message queue is removed, and the new message is placed at the head of the message queue.
The server according to claim 13, wherein the "save the message in the message queue according to the first preset rule" further includes:

When the number of messages in the message queue reaches a second preset threshold, generate warning information and send it to a preset terminal, and receive an instruction issued by the preset terminal to update the first preset threshold, respond to the instruction and Perform the first preset threshold update operation.
A computer-readable storage medium, characterized in that the computer-readable storage medium includes an offline message distribution program. When the offline message distribution program is executed by a processor, the following steps may be implemented:

A1. Receive the message published by the first client, determine the message queue corresponding to the message according to the attribute information of the message, and save the message in the message queue based on the first preset rule;

A2. Receive the connection instruction of the second client, obtain the online time and the last offline time of the second client, and determine the offline time period;

A3. Determine one or more message queues corresponding to the second client respectively, find out the messages of the second client in the offline time period from the one or more message queues respectively, and generate the first The offline message list of the two clients; and

A4. Distribute the messages in the offline message list to the second client based on the second preset rule.
The computer-readable storage medium according to claim 15, wherein the "save the message in the message queue according to the first preset rule" includes: obtaining a time stamp from attribute information of the message , According to the order of the timestamps from early to late, save the message in sequence at the head of the message queue corresponding to the message.
The computer-readable storage medium according to claim 15, wherein the "find messages of the second client in the offline time period from the one or more message queues respectively, as the Offline message of the second client", including:

Obtain the first message of a message queue, obtain a time stamp from the attribute information of the first message, and determine whether the time stamp is within the offline time period;

If yes, it is judged that the first message is an offline message, and the next message in the message queue is sequentially obtained and the judgment step is repeated;

If not, it is determined that the first message is not an offline message, and it is determined that there is no offline message of the second client in the message queue.
The computer-readable storage medium according to claim 17, wherein the second preset rule includes: according to the order of the offline messages in the offline message list, sending offline messages to the second client in sequence.
The computer-readable storage medium according to claim 18, wherein the second preset rule further comprises: when the second client corresponds to multiple offline message lists, determining the theme corresponding to each offline message list For the subscription time, the offline messages in each offline message list are distributed in order according to the order of the subscription time from morning to night.
The computer-readable storage medium according to claim 17, wherein the "save the message in the message queue according to the first preset rule" includes: when the number of messages in the message queue is the first When the threshold is preset, each time a new message is received, a message at the end of the message queue is removed, and the new message is placed at the head of the message queue.