Without knowing the top node, how to generate a parent-child node tree

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Since the project is going to have a sunburst chart, because the backend only helps me extract the flattened array of objects in the database, I need to process the data. For this, I have to deal with the data. The following is my data processing process.

// 本算法在不确定顶级节点的情况下，优先过滤出顶级节点，在进行遍历
// 进行数据的大量缓存，用空间换时间，让生成tree的速度像柔丝般顺滑
function generatorTree(data) {
  const value = 'value';
  const name = 'name';
  const id = 'id';
  const pid = 'pid';
  // 保存所有ID，然后找到pid没有对应节点的就是顶级节点
  const hasId = {};
  // 顶层父节点数组
  const topPIdArr = [];
  // 将每个节点对应的子节点对应起来
  const nodeToChildren = {};
  // 获取所有父ID（包括顶级节点的父ID）
  const pidSet = new Set();
  data.forEach(e => {
    // 之后通过topPIdArr数组可以通过深度遍历生成父子节点tree
    if (nodeToChildren[e[pid]]) {
      nodeToChildren[e[pid]].push({name: e[name], value: e[value], id: e[id], children: []})
    } else {
      nodeToChildren[e[pid]] = [{name: e[name], value: e[value], id: e[id], children: []}];
    }
    pidSet.add(e[pid]);
    hasId[e[id]] = true;
  });
  // 遍历父ID集合
  for (const pid of pidSet) {
    if (!hasId[pid]) {
      // 如果idObj没有该pid节点，说明它是顶级父节点
      topPIdArr.push(pid);
    }
  }
  // 如果你不想改变nodeToChildren，建议深拷贝一下，当然里面如果属性有undefined，函数或者symbol那你得自己实现一个深拷贝方法
  const copyNodeToChildren = JSON.parse(JSON.stringify(nodeToChildren));
  // 用来存储生成的树状结构数据
  const nodeTree = [];
  // 找到所有顶级节点，开始递归生成tree，tree，tree，真的脆
  data.filter(e => topPIdArr.includes(e.pid)).forEach((e, index) => {
    nodeTree.push({name: e[name], value: e[value], id: e[id], children: []});
    deepCreateTree(nodeTree[index].id, nodeTree[index].children);
  });
  // 通过深度优先遍历的思路，生成父子Tree
  function deepCreateTree (id, children) {
  // 存在的话，说明该id的节点存在子节点
    if (copyNodeToChildren[id]) {
    // 将数据推进对应id节点的children中
      children.push(...copyNodeToChildren[id]);
      copyNodeToChildren[id].forEach(e => {
        deepCreateTree(e.id, e.children);
      });
    }
  }
  console.log(nodeTree, 847587)
}

generatorTree([
  {id: 1, value: 2, name: 'A', pid: 0},
  {id: 2, value: 2, name:'B', pid: 1},
  {id: 3, value: 2, name:'C', pid: 2},
  {id: 4, value: 2, name:'D', pid: 3},
  {id: 5, value: 2, name:'E', pid: 0}
  ]);

If you like my implementation, you can share it with the link below, thank you
https://www.cnblogs.com/smallZoro/p/12695978.html