schemas: add geojson support

marshmallow_utils/schemas/__init__.py

@@ -0,0 +1,20 @@
+# -*- coding: utf-8 -*-
+#
+# Copyright (C) 2020 CERN.
+#
+# Marshmallow-Utils is free software; you can redistribute it and/or modify
+# it under the terms of the MIT License; see LICENSE file for more details.
+
+"""Marshmallow schemas."""
+
+from .geojson import GeoJSONSchema
+from .multipoint import MultiPointSchema
+from .point import PointSchema
+from .polygon import PolygonSchema
+
+__all__ = (
+    'GeoJSONSchema',
+    'MultiPointSchema',
+    'PointSchema',
+    'PolygonSchema',
+)

marshmallow_utils/schemas/geojson.py

@@ -0,0 +1,41 @@
+# -*- coding: utf-8 -*-
+#
+# Copyright (C) 2020 CERN.
+#
+# Marshmallow-Utils is free software; you can redistribute it and/or modify
+# it under the terms of the MIT License; see LICENSE file for more details.
+
+"""GeoJSON Schema."""
+
+from marshmallow import validate
+from marshmallow_oneofschema import OneOfSchema
+
+from ..fields import SanitizedUnicode
+from .multipoint import MultiPointSchema
+from .point import PointSchema
+from .polygon import PolygonSchema
+
+
+class GeoJSONSchema(OneOfSchema):
+    """GeoJSON schema.
+
+    Only Point, MultiPoint and Polygon are supported.
+    """
+
+    type_schemas = {
+        "point": PointSchema,
+        "multipoint": MultiPointSchema,
+        "polygon": PolygonSchema,
+    }
+
+    def get_obj_type(self, obj):
+        """Finds the object type in the dictoionary.
+
+        This function is needed because the schemas return the dict itself.
+        Not a geojson object.
+        """
+        obj_type = obj.get("type")
+        if not obj_type or obj_type not in self.type_schemas.keys():
+            raise Exception(f"Unknown GeoJSON object type: {obj_type}")
+
+        return obj_type

marshmallow_utils/schemas/multipoint.py

@@ -0,0 +1,38 @@
+# -*- coding: utf-8 -*-
+#
+# Copyright (C) 2020 CERN.
+#
+# Marshmallow-Utils is free software; you can redistribute it and/or modify
+# it under the terms of the MIT License; see LICENSE file for more details.
+
+"""GeoJSON MultiPoint Schema."""
+
+from geojson import MultiPoint
+from marshmallow import Schema, validates
+from marshmallow.exceptions import ValidationError
+from marshmallow.fields import Constant, Float, List
+
+
+class MultiPointSchema(Schema):
+    """GeoJSON MultiPoint schema."""
+
+    coordinates = List(List(Float), required=True)
+    type = Constant('multipoint')
+
+    @validates("coordinates")
+    def validate_data(self, data, **kwargs):
+        """Validate point.
+
+        From the `coordinates`, the first two elements are longitude
+        and latitude, or easting and northing, precisely in that order and
+        using decimal numbers. Altitude or elevation MAY be included as an
+        optional third element.
+        """
+        if not data:
+            raise ValidationError({"geojson": "coordinates must be present."})
+
+        multipoint = MultiPoint(data)
+        if not multipoint.is_valid:
+            errors = multipoint.errors()
+            raise ValidationError(
+                {"geojson": {"coordinates": errors}})

marshmallow_utils/schemas/point.py

@@ -0,0 +1,37 @@
+# -*- coding: utf-8 -*-
+#
+# Copyright (C) 2020 CERN.
+#
+# Marshmallow-Utils is free software; you can redistribute it and/or modify
+# it under the terms of the MIT License; see LICENSE file for more details.
+
+"""GeoJSON Point Schema."""
+
+from geojson import Point
+from marshmallow import Schema, validates
+from marshmallow.exceptions import ValidationError
+from marshmallow.fields import Constant, Float, List
+
+
+class PointSchema(Schema):
+    """GeoJSON Point schema."""
+
+    coordinates = List(Float, required=True)
+    type = Constant('point')
+
+    @validates("coordinates")
+    def validate_coordinates(self, data, **kwargs):
+        """Validate point.
+
+        From the `coordinates`, the first two elements are longitude
+        and latitude, or easting and northing, precisely in that order and
+        using decimal numbers. Altitude or elevation MAY be included as an
+        optional third element.
+        """
+        if not data:
+            raise ValidationError({"geojson": "coordinates must be present."})
+        point = Point(data)
+        if not point.is_valid:
+            errors = point.errors()
+            raise ValidationError(
+                {"geojson": {"coordinates": errors}})

marshmallow_utils/schemas/polygon.py

@@ -0,0 +1,40 @@
+# -*- coding: utf-8 -*-
+#
+# Copyright (C) 2020 CERN.
+#
+# Marshmallow-Utils is free software; you can redistribute it and/or modify
+# it under the terms of the MIT License; see LICENSE file for more details.
+
+"""GeoJSON Polygon Schema."""
+
+from geojson import Polygon
+from marshmallow import Schema, validates
+from marshmallow.exceptions import ValidationError
+from marshmallow.fields import Constant, Float, List
+
+
+class PolygonSchema(Schema):
+    """GeoJSON Point schema."""
+
+    coordinates = List(List(List(Float, required=True)))
+    type = Constant('polygon')
+
+    @validates("coordinates")
+    def validate_coordinates(self, data, **kwargs):
+        """Validate point.
+
+        For type "Polygon", the "coordinates" member MUST be an array of
+        linear ring coordinate arrays.
+
+        For Polygons with more than one of these rings, the first MUST be
+        the exterior ring, and any others MUST be interior rings.  The
+        exterior ring bounds the surface, and the interior rings (if
+        present) bound holes within the surface.
+        """
+        if not data:
+            raise ValidationError({"geojson": "coordinates must be present."})
+        polygon = Polygon(data)
+        if not polygon.is_valid:
+            errors = polygon.errors()
+            raise ValidationError(
+                {"geojson": {"coordinates": errors}})

setup.py

@@ -40,7 +40,9 @@
     'bleach>=3.0.0',
     'edtf>=4.0.1,<5.0.0',
     'ftfy>=4.4.3',
+    'geojson>=2.5.0',
     'marshmallow>=3.0.0,<4.0.0',
+    'marshmallow-oneofschema>=2.1.0',
     'pycountry>=18.12.8',
     'uritemplate>=3.0.1',
     'werkzeug>=1.0.0',

tests/schemas/test_geojson.py

@@ -0,0 +1,90 @@
+# -*- coding: utf-8 -*-
+#
+# Copyright (C) 2020 CERN.
+#
+# Marshmallow-Utils is free software; you can redistribute it and/or modify
+# it under the terms of the MIT License; see LICENSE file for more details.
+
+"""Tests for marshmallow GeoJSON schema."""
+
+import pytest
+from marshmallow import Schema, ValidationError
+
+from marshmallow_utils.schemas import GeoJSONSchema
+
+
+def test_point():
+    valid_full = {
+        "type": "point",
+        "coordinates": [-32.94682, -60.63932]
+    }
+
+    point = GeoJSONSchema().load(valid_full)
+    assert valid_full == point
+
+
+def test_point_fail():
+    invalid_input = {
+        "type": "point",
+        "coordinates": [-32.94682]
+    }
+    pytest.raises(ValidationError, GeoJSONSchema().load, invalid_input)
+
+
+def test_multipoint():
+    valid_full = {
+        "type": "multipoint",
+        "coordinates": [[-32.94682, -60.63932], [-32.94682, -60.63932, 10.0]]
+    }
+
+    multipoint = GeoJSONSchema().load(valid_full)
+    assert valid_full == multipoint
+
+
+def test_multipoint_fail():
+    invalid_input = {
+        "type": "multipoint",
+        "coordinates": [-32.94682, -60.63932]
+    }
+    pytest.raises(ValidationError, GeoJSONSchema().load, invalid_input)
+
+
+def test_polygon():
+    valid_full = {
+        "type": "polygon",
+        "coordinates": [[
+            [2.38, 57.322], [23.194, -20.28], [-120.43, 19.15], [2.38, 57.322]
+        ]]
+    }
+
+    point = GeoJSONSchema().load(valid_full)
+    assert valid_full == point
+
+
+def test_polygon_fail():
+    invalid_input = {
+        "type": "polygon",
+        "coordinates": [[[2.38, 57.322], [23.194, -20.28], [2.38, 57.322]]]
+    }
+    pytest.raises(ValidationError, GeoJSONSchema().load, invalid_input)
+
+
+@pytest.mark.parametrize("geotype", [("point"), ("multipoint")])
+def test_point_no_coordinates_fail(geotype):
+    invalid_point = {"type": geotype}
+
+    pytest.raises(ValidationError, GeoJSONSchema().load, invalid_point)
+
+
+def test_not_supported_type_fail():
+    invalid_type = {"type": "invalid"}
+
+    pytest.raises(ValidationError, GeoJSONSchema().load, invalid_type)
+
+
+def test_no_type_fail():
+    invalid_no_type = {
+        "coordinates": [-32.94682, -60.63932]
+    }
+
+    pytest.raises(ValidationError, GeoJSONSchema().load, invalid_no_type)

tests/schemas/test_multipoint.py

@@ -0,0 +1,39 @@
+# -*- coding: utf-8 -*-
+#
+# Copyright (C) 2020 CERN.
+#
+# Marshmallow-Utils is free software; you can redistribute it and/or modify
+# it under the terms of the MIT License; see LICENSE file for more details.
+
+"""Tests for marshmallow GeoJSON MultiPoint schema."""
+
+import pytest
+from marshmallow import Schema, ValidationError
+
+from marshmallow_utils.schemas import MultiPointSchema
+
+
+@pytest.mark.parametrize("coordinates", [
+    ([[-32.94682, -60.63932], [-32.94682, -60.63932, 10.0]]),
+    ([[-32.99, -60.63], [-32.94, -60.63], [-32.92, -60.32, 10.0]]),
+])
+def test_multipoint(coordinates):
+    valid_full = {
+        "type": "multipoint",
+        "coordinates": coordinates
+    }
+    assert valid_full == MultiPointSchema().load(valid_full)
+
+
+@pytest.mark.parametrize("coordinates", [
+    ("-32.94682,-60.63932, -32.94682, -60.63932, 10.0"),
+    (["-32.94682,-60.63932", "-32.94682, -60.63932, 10.0"]),
+    ([-32.94682, -60.63932, 10.0, 10.0]),
+    ([[-32.99, -60.63], [-32.94], [-32.92, -60.32, 10.0]])
+])
+def test_multipoint_fail(coordinates):
+    invalid_point = {
+        "type": "multipoint",
+        "coordinates": coordinates
+    }
+    pytest.raises(ValidationError, MultiPointSchema().load, invalid_point)

tests/schemas/test_point.py

@@ -0,0 +1,42 @@
+# -*- coding: utf-8 -*-
+#
+# Copyright (C) 2020 CERN.
+#
+# Marshmallow-Utils is free software; you can redistribute it and/or modify
+# it under the terms of the MIT License; see LICENSE file for more details.
+
+"""Tests for marshmallow GeoJSON Point schema."""
+
+import pytest
+from marshmallow import Schema, ValidationError
+
+from marshmallow_utils.schemas import PointSchema
+
+
+@pytest.mark.parametrize("coordinates", [
+    ([-32.94682, -60.63932]),
+    ([-32.94682, -60.63932, 10.0]),
+])
+def test_point(coordinates):
+    valid_full = {
+        "type": "point",
+        "coordinates": coordinates
+    }
+    assert valid_full == PointSchema().load(valid_full)
+
+
+# NOTE: ["-32.94682", "-60.63932"] is valid because the Float field
+# deserializes properly the string into float, so it becomes
+# [-32.94682, -60.63932]
+@pytest.mark.parametrize("coordinates", [
+    ("-32.94682,-60.63932"),
+    (["-32.94682,-60.63932"]),
+    ([-32.94682, -60.63932, 10.0, 10.0]),
+    ([-32.94682])
+])
+def test_point_fail(coordinates):
+    invalid_point = {
+        "type": "point",
+        "coordinates": coordinates
+    }
+    pytest.raises(ValidationError, PointSchema().load, invalid_point)