Node.js中@turf/centroid导入后报错turf未定义，求正确用法

问题详情 #

已在package.json中安装@turf/centroid模块：

{
  "name": "api_geoservices",
  "version": "1.0.0",
  "type": "module",
  "scripts": {
    "start": "vite",
    "build": "vite build",
    "serve": "vite preview",
    "test": "node test.js"
  },
  "devDependencies": {
    "vite": "^4.0.4"
  },
  "dependencies": {
    "@turf/centroid": "^6.5.0",
    "ol": "latest",
    "ol-ext": "^4.0.13",
    "proj4": "^2.9.2"
  }
}

在main.js中尝试使用时：

// imports
import centroid from "@turf/centroid"
...
const featuresPoint = []
turf.featureEach(reponse, function (operation) {
  const centroide = turf.centroid(operation)
  const pointCentroid = opeGeoJsonFormat.readFeature(centroide)
  featuresPoint.push(pointCentroid)
....
})

浏览器控制台报错：Uncaught (in promise) ReferenceError: turf is not defined

解决方案 #

方案一：单独导入所需的Turf子模块 #

你安装的是单个Turf子模块而非完整包，不存在全局turf对象，需单独导入每个用到的函数：

1. 安装并导入featureEach（该函数属于@turf/meta模块）：

import centroid from "@turf/centroid";
import featureEach from "@turf/meta";

2. 替换代码中的turf调用：

const featuresPoint = [];
featureEach(reponse, function (operation) {
  const centroide = centroid(operation);
  const pointCentroid = opeGeoJsonFormat.readFeature(centroide);
  featuresPoint.push(pointCentroid);
  // ...
});

方案二：安装完整Turf包 #

如果需要使用多个Turf函数，可直接安装完整包：

1. 执行安装命令：

npm install turf

2. 导入完整模块：

import * as turf from "turf";

之后就可以像原代码那样用turf.centroid和turf.featureEach调用函数。

内容的提问来源于stack exchange，提问作者Leehan