feature_conversion.py•13.8 kB
# 特征转换函数
from fastmcp import FastMCP
from turf_mcp.utils import call_js_script
feature_conversion_mcp = FastMCP("feature_conversion")
@feature_conversion_mcp.tool
async def combine(feature_collection: str) -> str:
"""
将特征集合合并为复合几何图形。
此功能将点、线或多边形特征集合分别合并为多点、多线或多边形复合几何图形。
Args:
feature_collection: GeoJSON 特征集合
- 类型: str (JSON 字符串格式的 GeoJSON)
- 格式: 必须符合 GeoJSON FeatureCollection 规范
- 坐标系: WGS84 (经度在前，纬度在后)
- 示例: '{"type": "FeatureCollection", "features": [{"type": "Feature", "geometry": {"type": "Point", "coordinates": [19.026432, 47.49134]}}, {"type": "Feature", "geometry": {"type": "Point", "coordinates": [19.074497, 47.509548]}}]}'
Returns:
str: JSON 字符串格式的合并后 GeoJSON 特征集合
- 类型: GeoJSON FeatureCollection with MultiPoint, MultiLineString or MultiPolygon features
- 格式: {"type": "FeatureCollection", "features": [{"type": "Feature", "geometry": {"type": "...", "coordinates": [...]}}]}
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
>>> fc = '{"type": "FeatureCollection", "features": [{"type": "Feature", "geometry": {"type": "Point", "coordinates": [19.026432, 47.49134]}}, {"type": "Feature", "geometry": {"type": "Point", "coordinates": [19.074497, 47.509548]}}]}'
>>> result = asyncio.run(combine(fc))
>>> print(result)
'{"type": "FeatureCollection", "features": [{"type": "Feature", "geometry": {"type": "MultiPoint", "coordinates": [[19.026432, 47.49134], [19.074497, 47.509548]]}}]}'
Notes:
- 输入参数 feature_collection 必须是有效的 JSON 字符串
- 坐标顺序为 [经度, 纬度] (WGS84 坐标系)
- 点特征会合并为多点，线特征会合并为多线，多边形特征会合并为多多边形
- 依赖于 Turf.js 库和 Node.js 环境
"""
js_script = f"""
const turf = require('@turf/turf');
const featureCollection = JSON.parse('{feature_collection}');
const result = turf.combine(featureCollection);
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)}")
@feature_conversion_mcp.tool
async def explode(geojson: str) -> str:
"""
将几何图形分解为单独的点特征。
此功能将给定的 GeoJSON 特征分解为所有顶点坐标的单独点特征集合。
Args:
geojson: GeoJSON 对象
- 类型: str (JSON 字符串格式的 GeoJSON)
- 格式: 任何有效的 GeoJSON 对象
- 坐标系: WGS84 (经度在前，纬度在后)
- 示例: '{"type": "Polygon", "coordinates": [[[-81, 41], [-88, 36], [-84, 31], [-80, 33], [-77, 39], [-81, 41]]]}'
Returns:
str: JSON 字符串格式的点特征集合
- 类型: GeoJSON FeatureCollection with Point features
- 格式: {"type": "FeatureCollection", "features": [{"type": "Feature", "geometry": {"type": "Point", "coordinates": [lng, lat]}}, ...]}
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
>>> polygon = '{"type": "Polygon", "coordinates": [[[-81, 41], [-88, 36], [-84, 31], [-80, 33], [-77, 39], [-81, 41]]]}'
>>> result = asyncio.run(explode(polygon))
>>> print(result)
'{"type": "FeatureCollection", "features": [{"type": "Feature", "geometry": {"type": "Point", "coordinates": [-81, 41]}}, ...]}'
Notes:
- 输入参数 geojson 必须是有效的 JSON 字符串
- 坐标顺序为 [经度, 纬度] (WGS84 坐标系)
- 返回所有几何图形顶点的点特征集合
- 依赖于 Turf.js 库和 Node.js 环境
"""
js_script = f"""
const turf = require('@turf/turf');
const geojson = JSON.parse('{geojson}');
const result = turf.explode(geojson);
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)}")
@feature_conversion_mcp.tool
async def flatten(geojson: str) -> str:
"""
将复合几何图形展平为简单几何图形。
此功能将多几何图形（如多点、多线、多多边形）展平为对应的简单几何图形特征集合。
Args:
geojson: GeoJSON 对象
- 类型: str (JSON 字符串格式的 GeoJSON)
- 格式: 任何有效的 GeoJSON 对象
- 坐标系: WGS84 (经度在前，纬度在后)
- 示例: '{"type": "MultiPolygon", "coordinates": [[[[102.0, 2.0], [103.0, 2.0], [103.0, 3.0], [102.0, 3.0], [102.0, 2.0]]], [[[100.0, 0.0], [101.0, 0.0], [101.0, 1.0], [100.0, 1.0], [100.0, 0.0]]]]}'
Returns:
str: JSON 字符串格式的展平后特征集合
- 类型: GeoJSON FeatureCollection with simple geometry features
- 格式: {"type": "FeatureCollection", "features": [{"type": "Feature", "geometry": {"type": "...", "coordinates": [...]}}, ...]}
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
>>> multi_polygon = '{"type": "MultiPolygon", "coordinates": [[[[102.0, 2.0], [103.0, 2.0], [103.0, 3.0], [102.0, 3.0], [102.0, 2.0]]], [[[100.0, 0.0], [101.0, 0.0], [101.0, 1.0], [100.0, 1.0], [100.0, 0.0]]]]}'
>>> result = asyncio.run(flatten(multi_polygon))
>>> print(result)
'{"type": "FeatureCollection", "features": [{"type": "Feature", "geometry": {"type": "Polygon", "coordinates": [[[102.0, 2.0], [103.0, 2.0], [103.0, 3.0], [102.0, 3.0], [102.0, 2.0]]]}}, ...]}'
Notes:
- 输入参数 geojson 必须是有效的 JSON 字符串
- 坐标顺序为 [经度, 纬度] (WGS84 坐标系)
- 多几何图形会被展平为对应的简单几何图形集合
- 依赖于 Turf.js 库和 Node.js 环境
"""
js_script = f"""
const turf = require('@turf/turf');
const geojson = JSON.parse('{geojson}');
const result = turf.flatten(geojson);
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)}")
@feature_conversion_mcp.tool
async def line_to_polygon(line: str, options: str = None) -> str:
"""
将线转换为多边形。
此功能将线几何图形转换为多边形几何图形，自动闭合线段的起点和终点。
Args:
line: GeoJSON 线特征或几何图形
- 类型: str (JSON 字符串格式的 GeoJSON)
- 格式: 必须符合 GeoJSON LineString 或 MultiLineString 规范
- 坐标系: WGS84 (经度在前，纬度在后)
- 示例: '{"type": "LineString", "coordinates": [[125, -30], [145, -30], [145, -20], [125, -20], [125, -30]]}'
options: 可选参数配置
- 类型: str (JSON 字符串) 或 None
- 可选字段:
- properties: 传递给多边形的属性对象
- autoComplete: 是否自动完成线段闭合
- orderCoords: 是否重新排序坐标
- mutate: 是否修改原始线特征
- 示例: '{"properties": {"name": "converted polygon"}}'
Returns:
str: JSON 字符串格式的 GeoJSON Polygon 或 MultiPolygon 特征
- 类型: GeoJSON Feature with Polygon or MultiPolygon geometry
- 格式: {"type": "Feature", "geometry": {"type": "Polygon", "coordinates": [...]}}
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
>>> line = '{"type": "LineString", "coordinates": [[125, -30], [145, -30], [145, -20], [125, -20], [125, -30]]}'
>>> options = '{"properties": {"name": "converted polygon"}}'
>>> result = asyncio.run(line_to_polygon(line, options))
>>> print(result)
'{"type": "Feature", "geometry": {"type": "Polygon", "coordinates": [[[125, -30], [145, -30], [145, -20], [125, -20], [125, -30]]]}}'
Notes:
- 输入参数 line 和 options 必须是有效的 JSON 字符串
- 坐标顺序为 [经度, 纬度] (WGS84 坐标系)
- 线会自动闭合形成多边形边界
- 依赖于 Turf.js 库和 Node.js 环境
"""
options_param = options if options else '{}'
js_script = f"""
const turf = require('@turf/turf');
const line = JSON.parse('{line}');
const options = JSON.parse('{options_param}');
const result = turf.lineToPolygon(line, options);
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)}")
@feature_conversion_mcp.tool
async def polygonize(geojson: str) -> str:
"""
将线几何图形转换为多边形。
此功能将线或多线几何图形转换为多边形几何图形集合，基于线的闭合区域创建多边形。
Args:
geojson: GeoJSON 对象
- 类型: str (JSON 字符串格式的 GeoJSON)
- 格式: 必须符合 GeoJSON FeatureCollection, Geometry 或 Feature 规范，包含 LineString 或 MultiLineString
- 坐标系: WGS84 (经度在前，纬度在后)
- 示例: '{"type": "FeatureCollection", "features": [{"type": "Feature", "geometry": {"type": "LineString", "coordinates": [[0, 0], [1, 0], [1, 1], [0, 1], [0, 0]]}}]}'
Returns:
str: JSON 字符串格式的多边形特征集合
- 类型: GeoJSON FeatureCollection with Polygon features
- 格式: {"type": "FeatureCollection", "features": [{"type": "Feature", "geometry": {"type": "Polygon", "coordinates": [...]}}, ...]}
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
>>> geojson = '{"type": "FeatureCollection", "features": [{"type": "Feature", "geometry": {"type": "LineString", "coordinates": [[0, 0], [1, 0], [1, 1], [0, 1], [0, 0]]}}]}'
>>> result = asyncio.run(polygonize(geojson))
>>> print(result)
'{"type": "FeatureCollection", "features": [{"type": "Feature", "geometry": {"type": "Polygon", "coordinates": [[[0, 0], [1, 0], [1, 1], [0, 1], [0, 0]]]}}]}'
Notes:
- 输入参数 geojson 必须是有效的 JSON 字符串
- 坐标顺序为 [经度, 纬度] (WGS84 坐标系)
- 基于线的闭合区域创建多边形
- 依赖于 Turf.js 库和 Node.js 环境
"""
js_script = f"""
const turf = require('@turf/turf');
const geojson = JSON.parse('{geojson}');
const result = turf.polygonize(geojson);
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)}")
@feature_conversion_mcp.tool
async def polygon_to_line(polygon: str) -> str:
"""
将多边形转换为线几何图形。
此功能将多边形或多边形几何图形转换为线或多线几何图形，提取多边形的边界。
Args:
polygon: GeoJSON 多边形特征或几何图形
- 类型: str (JSON 字符串格式的 GeoJSON)
- 格式: 必须符合 GeoJSON Polygon 或 MultiPolygon 规范
- 坐标系: WGS84 (经度在前，纬度在后)
- 示例: '{"type": "Polygon", "coordinates": [[[125, -30], [145, -30], [145, -20], [125, -20], [125, -30]]]}'
Returns:
str: JSON 字符串格式的 GeoJSON LineString 或 MultiLineString 特征
- 类型: GeoJSON Feature with LineString or MultiLineString geometry
- 格式: {"type": "Feature", "geometry": {"type": "LineString", "coordinates": [...]}}
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
>>> polygon = '{"type": "Polygon", "coordinates": [[[125, -30], [145, -30], [145, -20], [125, -20], [125, -30]]]}'
>>> result = asyncio.run(polygon_to_line(polygon))
>>> print(result)
'{"type": "Feature", "geometry": {"type": "LineString", "coordinates": [[125, -30], [145, -30], [145, -20], [125, -20], [125, -30]]}}'
Notes:
- 输入参数 polygon 必须是有效的 JSON 字符串
- 坐标顺序为 [经度, 纬度] (WGS84 坐标系)
- 提取多边形的边界作为线几何图形
- 依赖于 Turf.js 库和 Node.js 环境
"""
js_script = f"""
const turf = require('@turf/turf');
const polygon = JSON.parse('{polygon}');
const result = turf.polygonToLine(polygon);
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)}")