joins.py•6.68 kB
# 空间连接和属性关联函数
from fastmcp import FastMCP
from turf_mcp.utils import call_js_script
joins_mcp = FastMCP("joins")
@joins_mcp.tool
async def pointsWithinPolygon(points: str, polygons: str) -> str:
"""
查找多边形内部的点。
此功能识别位于多边形或多边形集合内部的点特征，返回这些点特征。
Args:
points: 点特征集合
- 类型: str (JSON 字符串格式的 GeoJSON FeatureCollection)
- 格式: FeatureCollection with Point features
- 示例: '{"type": "FeatureCollection", "features": [{"type": "Feature", "geometry": {"type": "Point", "coordinates": [-75.343, 39.984]}}, ...]}'
polygons: 多边形特征集合
- 类型: str (JSON 字符串格式的 GeoJSON FeatureCollection)
- 格式: FeatureCollection with Polygon or MultiPolygon features
- 示例: '{"type": "FeatureCollection", "features": [{"type": "Feature", "geometry": {"type": "Polygon", "coordinates": [[[125, -15], [113, -22], [154, -27], [144, -15], [125, -15]]]}}, ...]}'
Returns:
str: JSON 字符串格式的 GeoJSON FeatureCollection
- 类型: GeoJSON FeatureCollection with Point features
- 格式: {"type": "FeatureCollection", "features": [{"type": "Feature", "geometry": {"type": "Point", "coordinates": [lng, lat]}}, ...]}
- 示例: '{"type": "FeatureCollection", "features": [{"type": "Feature", "geometry": {"type": "Point", "coordinates": [-75.343, 39.984]}}, ...]}'
Raises:
Exception: 当 JavaScript 执行失败、超时或输入数据格式错误时抛出异常
Example:
>>> import asyncio
>>> points = '{"type": "FeatureCollection", "features": [{"type": "Feature", "geometry": {"type": "Point", "coordinates": [-75.343, 39.984]}}]}'
>>> polygons = '{"type": "FeatureCollection", "features": [{"type": "Feature", "geometry": {"type": "Polygon", "coordinates": [[[125, -15], [113, -22], [154, -27], [144, -15], [125, -15]]]}}]}'
>>> result = asyncio.run(pointsWithinPolygon(points, polygons))
>>> print(result)
'{"type": "FeatureCollection", "features": [{"type": "Feature", "geometry": {"type": "Point", "coordinates": [-75.343, 39.984]}}, ...]}'
Notes:
- 输入参数 points 和 polygons 必须是有效的 JSON 字符串
- 坐标顺序为 [经度, 纬度] (WGS84 坐标系)
- 仅返回位于多边形内部的点
- 位于多边形边界上的点可能被视为内部或外部，取决于具体实现
- 依赖于 Turf.js 库和 Node.js 环境
"""
js_script = f"""
const turf = require('@turf/turf');
const points = JSON.parse('{points}');
const polygons = JSON.parse('{polygons}');
const result = turf.pointsWithinPolygon(points, polygons);
console.log(JSON.stringify(result));
"""
try:
return await call_js_script(js_script)
except Exception as e:
raise Exception(f"执行异常: {str(e)}")
@joins_mcp.tool
async def tag(points: str, polygons: str, field: str, out_field: str) -> str:
"""
为点特征添加多边形属性。
此功能将多边形特征的属性值关联到位于多边形内部的点特征上。
Args:
points: 点特征集合
- 类型: str (JSON 字符串格式的 GeoJSON FeatureCollection)
- 格式: FeatureCollection with Point features
- 示例: '{"type": "FeatureCollection", "features": [{"type": "Feature", "geometry": {"type": "Point", "coordinates": [-75.343, 39.984]}}, ...]}'
polygons: 多边形特征集合
- 类型: str (JSON 字符串格式的 GeoJSON FeatureCollection)
- 格式: FeatureCollection with Polygon or MultiPolygon features
- 示例: '{"type": "FeatureCollection", "features": [{"type": "Feature", "geometry": {"type": "Polygon", "coordinates": [[[125, -15], [113, -22], [154, -27], [144, -15], [125, -15]]], "properties": {"name": "Area A"}}, ...]}'
field: 源字段名
- 类型: str
- 描述: 多边形特征中要提取的属性字段名
- 示例: 'name'
out_field: 输出字段名
- 类型: str
- 描述: 点特征中要创建的属性字段名
- 示例: 'area_name'
Returns:
str: JSON 字符串格式的 GeoJSON FeatureCollection
- 类型: GeoJSON FeatureCollection with Point features
- 格式: {"type": "FeatureCollection", "features": [{"type": "Feature", "geometry": {"type": "Point", "coordinates": [lng, lat]}, "properties": {...}}, ...]}
- 示例: '{"type": "FeatureCollection", "features": [{"type": "Feature", "geometry": {"type": "Point", "coordinates": [-75.343, 39.984]}, "properties": {"area_name": "Area A"}}, ...]}'
Raises:
Exception: 当 JavaScript 执行失败、超时或输入数据格式错误时抛出异常
Example:
>>> import asyncio
>>> points = '{"type": "FeatureCollection", "features": [{"type": "Feature", "geometry": {"type": "Point", "coordinates": [-75.343, 39.984]}}]}'
>>> polygons = '{"type": "FeatureCollection", "features": [{"type": "Feature", "geometry": {"type": "Polygon", "coordinates": [[[125, -15], [113, -22], [154, -27], [144, -15], [125, -15]]], "properties": {"name": "Area A"}}]}'
>>> result = asyncio.run(tag(points, polygons, 'name', 'area_name'))
>>> print(result)
'{"type": "FeatureCollection", "features": [{"type": "Feature", "geometry": {"type": "Point", "coordinates": [-75.343, 39.984]}, "properties": {"area_name": "Area A"}}, ...]}'
Notes:
- 输入参数 points 和 polygons 必须是有效的 JSON 字符串
- 坐标顺序为 [经度, 纬度] (WGS84 坐标系)
- 仅对位于多边形内部的点添加属性
- 如果一个点位于多个多边形内，将使用最后一个匹配的多边形属性
- 依赖于 Turf.js 库和 Node.js 环境
"""
js_script = f"""
const turf = require('@turf/turf');
const points = JSON.parse('{points}');
const polygons = JSON.parse('{polygons}');
const field = '{field}';
const outField = '{out_field}';
const result = turf.tag(points, polygons, field, outField);
console.log(JSON.stringify(result));
"""
try:
return await call_js_script(js_script)
except Exception as e:
raise Exception(f"执行异常: {str(e)}")