[WiP] Export results

docs/source/api.rst

@@ -64,3 +64,17 @@ Helper
 
 .. automodule:: overpy.helper
     :members:
+
+
+Format/Export
+-------------
+
+.. warning::
+
+    This feature is in pre alpha stage. Please report any issues.
+
+.. automodule:: overpy.format.geojson
+    :members:
+
+.. automodule:: overpy.format.osm_xml
+    :members:

overpy/format/geojson.py

@@ -0,0 +1,63 @@
+import json
+from typing import Any, Dict, Optional, TextIO
+
+import overpy
+
+
+def dump(result: overpy.Result, fp: TextIO, nodes: bool = False, ways: bool = False, json_args: Optional[dict] = None):
+    """
+    Use the result from the Overpass API to generate GeoJSON.
+
+    More information:
+
+    * http://geojson.org/
+
+    :param result: The result from the Overpass API
+    :param fp: Filepointer to use
+    :param nodes: Export nodes
+    :param ways: Export ways
+    :param json_args: Additional arguments passed to json.dump(...)
+    :return:
+    """
+    features = []
+    if nodes:
+        for node in result.nodes:
+            properties: Dict[str, Any] = {}
+            features.append({
+                "type": "Feature",
+                "geometry": {
+                    "type": "Point",
+                    "coordinates": [
+                        float(node.lon),
+                        float(node.lat)
+                    ]
+                },
+                "properties": properties
+            })
+
+    if ways:
+        for way in result.ways:
+            properties = {}
+            coordinates = []
+            for node in way.nodes:
+                coordinates.append([
+                    float(node.lon),
+                    float(node.lat)
+                ])
+            features.append({
+                "type": "Feature",
+                "geometry": {
+                    "type": "LineString",
+                    "coordinates": coordinates
+                },
+                "properties": properties
+            })
+
+    geojson = {
+        "type": "FeatureCollection",
+        "features": features
+    }
+
+    if json_args is None:
+        json_args = {}
+    json.dump(geojson, fp, **json_args)

overpy/format/osm_xml.py

@@ -0,0 +1,111 @@
+from typing import TextIO
+from xml.sax.saxutils import escape
+
+import overpy
+
+
+def dump(result: overpy.Result, fp: TextIO):
+    """
+    Use the result from the Overpass API to generate OSM XML
+
+    More information:
+
+    * http://wiki.openstreetmap.org/wiki/OSM_XML
+
+    :param result: The result from the Overpass API
+    :param fp: Filepointer to use
+    :return:
+    """
+    fp.write('<?xml version="1.0" encoding="UTF-8"?>\n')
+    fp.write('<osm version="0.6" generator="OverPy {0}">\n'.format(overpy.__version__))
+    lat_min = result.nodes[0].lat
+    lat_max = lat_min
+    lon_min = result.nodes[0].lon
+    lon_max = lon_min
+    for node in result.nodes:
+        if node.lat < lat_min:
+            lat_min = node.lat
+        elif node.lat > lat_max:
+            lat_max = node.lat
+
+        if node.lon < lon_min:
+            lon_min = node.lon
+        elif node.lon > lon_max:
+            lon_max = node.lon
+
+    fp.write(
+        '<bounds minlat="{0:f}" minlon="{1:f}" maxlat="{2:f}" maxlon="{3:f}"/>\n'.format(
+            lat_min,
+            lon_min,
+            lat_max,
+            lon_max
+        )
+    )
+
+    for node in result.nodes:
+        fp.write(
+            '<node id="{0:d}" lat="{1:f}" lon="{2:f}"'.format(
+                node.id,
+                node.lat,
+                node.lon
+            )
+        )
+        if len(node.tags) == 0:
+            fp.write('/>\n')
+            continue
+        fp.write('>\n')
+        for k, v in node.tags.items():
+            fp.write(
+                '<tag k="{0:s}" v="{1:s}"/>\n'.format(
+                    escape(k),
+                    escape(v)
+                )
+            )
+        fp.write('</node>\n')
+
+    for way in result.ways:
+        fp.write('<way id="{0:d}"'.format(way.id))
+        if len(way.nodes) == 0 and len(way.tags) == 0:
+            fp.write('/>\n')
+            continue
+        fp.write('>\n')
+        for node in way.nodes:
+            fp.write('<nd ref="{0:d}"/>\n'.format(node.id))
+
+        for k, v in way.tags.items():
+            fp.write(
+                '<tag k="{0:s}" v="{1:s}"/>\n'.format(
+                    escape(k),
+                    escape(v)
+                )
+            )
+
+        fp.write('</way>\n')
+
+    for relation in result.relations:
+        fp.write('<relation id="{0:d}'.format(relation.id))
+        if len(relation.tags) == 0 and len(relation.members) == 0:
+            fp.write('/>\n')
+
+        for member in relation.members:
+            if not isinstance(member, overpy.RelationMember):
+                continue
+            fp.write(
+                '<member type="{0:s}" ref="{1:d}" role="{2:s}"/>\n'.format(
+                    member._type_value,
+                    member.ref,
+                    member.role
+                )
+            )
+
+        for k, v in relation.tags.items():
+            fp.write(
+                '<tag k="{0:s}" v="{1:s}"/>\n'.format(
+                    escape(k),
+                    escape(v)
+                )
+            )
+
+        fp.write('</relation>\n')
+
+    fp.write('</osm>')

tests/test_export.py

@@ -0,0 +1,22 @@
+import overpy
+from overpy.format import geojson, osm_xml
+
+from tests import read_file
+
+from io import StringIO
+
+
+class TestGeoJSON(object):
+    def test_node01(self):
+        api = overpy.Overpass()
+        result = api.parse_json(read_file("json/node-01.json"))
+        fp = StringIO()
+        geojson.dump(result, fp, nodes=True, ways=True)
+
+
+class TestOSMXML(object):
+    def test_node01(self):
+        api = overpy.Overpass()
+        result = api.parse_json(read_file("json/node-01.json"))
+        fp = StringIO()
+        osm_xml.dump(result, fp)