一、架构设计原理

基于EventSource+差异算法+操作转换实现的轻量级同步系统，支持实时数据更新和多客户端协同

二、核心功能实现

1. 数据同步核心类

class DataSync {
    constructor(options) {
        this.state = options.initialState || {};
        this.subscribers = new Set();
        this.pendingChanges = [];
        this.version = 0;
        this.initEventSource(options.url);
    }

    initEventSource(url) {
        this.eventSource = new EventSource(url);
        this.eventSource.onmessage = (event) => {
            const change = JSON.parse(event.data);
            this.applyRemoteChange(change);
        };
    }

    applyChange(change) {
        this.version++;
        change.version = this.version;
        this.pendingChanges.push(change);
        this.applyLocalChange(change);
        this.sendChangeToServer(change);
    }

    applyLocalChange(change) {
        // 实现差异合并算法
        this.state = this.mergeChanges(this.state, change);
        this.notifySubscribers();
    }
}

2. 冲突解决算法

mergeChanges(state, change) {
    const newState = {...state};
    const conflictResolver = {
        'OVERWRITE': () => change.value,
        'MERGE': () => ({...state[change.key], ...change.value}),
        'ARRAY_PUSH': () => [...state[change.key], ...change.value]
    };
    
    newState[change.key] = conflictResolver[change.strategy]();
    return newState;
}

resolveConflicts(current, incoming) {
    if (current.version > incoming.version) {
        return this.mergeChanges(incoming, {
            ...current,
            strategy: 'MERGE'
        });
    }
    return this.mergeChanges(current, incoming);
}

3. 性能优化方案

• 批量更新：使用requestAnimationFrame合并渲染
• 差异压缩：只同步变化的属性
• 内存优化：限制历史记录长度
• 延迟同步：网络不佳时启用队列