Design And Implementation Of Cooperative Editing System Based On Web Socket

With the information revolution,the rapid development of computer technology and the popularization of network communication,the interaction between people has gradually crossed the gap between time and space,making collaborative operation possible.Collaborative editing system is designed to meet the requirement of correctness and consistency of online editing documents by multiple people at the same time.The collaborative editing system has the following basic functions: Only users with corresponding permissions can perform corresponding operations on the document.Users without enough permissions or insufficient permissions cannot perform his unauthorized operations;files need to be managed systematically;users can edit documents.Concurrency control and consistency maintenance are required to prevent inconsistencies in different copies of the document;the document can be versioned during the editing process,and the Undo operation is used to undo the operation of the document to make the document fall back to the historical version;the system uses Centralized architecture,all operations performed by the front-end user on the document need to be passed to the server to act on the document record of the database document table.In order to prevent the same document from being inconsistent due to different user edits,their respective document copies are inconsistent.Each user's action on his copy of the document must be synchronized to a copy of the document of the other user in a timely manner.In order to realize the functions of the above system,I mainly designed five modules: authority control,file management,concurrent operation control,operation rollback,and message push.The permission control module mainly carries out the design: when the file is operated,the online file needs to be controlled by reading and writing.The editing permission can be edited online.The file permission can only be viewed online.When the file is created,it must be The file gives the reader the writer and how to handle the file permissions.When the file permissions are modified,the permissions of the file and the upper folder and the subfiles must be redefined.The file management module mainly implements the file management of the online documents.Users can create/delete files,upload/download files,import/export files,copy/move files to specific locations,bookmark/un-collect files,rename files,display recently updated files,blur search files by name,etc.System management;concurrent operation control module mainly considers that when multiple people edit the same document online at the same time,each user only edits their own copy,so that the copies of different users will accept different operations of the user under their respective edits,which will inevitably lead to Consistency maintenance problem,ie no After a user creates a different copies inconsistent operation of the converter technology allows users unrestricted local operation,it will conflict each user with an operation applied to the conversion of document,without requiring an additional operation to apply the lock or token.Therefore,even if users collaborate on a highlatency WAN,they can achieve good local responsiveness.At the same time,the operation conversion technology will retain the effect of all user operations,and automatically merge all the effects of user operations without changing their "willingness to operate",avoiding overwriting and rewriting between operations,using operation conversion algorithms.Users with editing rights ensure the correctness and consistency of the document when editing the same document at the same time,ensuring that the document does not go wrong;the operation rollback module allows the user to see all the history records of the document from the establishment to the present,and use the operation to merge and execute Undo.The operation causes the document to fall back to a certain version of the history;the message push module uses the WebSocket protocol of the full-duplex communication of the front and rear ends to implement a user's operation on a document to be displayed in real time to a copy of the document of another user.After the system coding is implemented,the system is tested with V model.Firstly,the sub-functions of each module are unit tested,then the sub-functions of each module are connected in series for integration test.Finally,the system is tested through a complete process.After the test is completed,the code is packaged and distributed to the server through the packaged server.Users can login remotely and use the system through UI at the front of the browser.