support geo.{intersects, distance, length}

updated query parsing for geo.* functions, and added django backend
implementation.

-add GEOGRAPHY token and Geography AST node
-account for identifier namespace in various places
-add django implementation using django.contrib.gis
-use '__' for namespace separator in backend function names
-fix geo.distance number of args

odata_query/ast.py

@@ -19,6 +19,9 @@ class Identifier(_Node):
     name: str
     namespace: Tuple[str, ...] = field(default_factory=tuple)
 
+    def full_name(self):
+        return '.'.join(self.namespace + (self.name,))
+
 
 @dataclass(frozen=True)
 class Attribute(_Node):
@@ -81,6 +84,14 @@ def py_val(self) -> str:
         return self.val
 
 
+@dataclass(frozen=True)
+class Geography(_Literal):
+    val: str
+
+    def wkt(self):
+        return self.val
+
+
 @dataclass(frozen=True)
 class Date(_Literal):
     val: str

odata_query/django/django_q.py

@@ -17,6 +17,9 @@
 )
 from django.db.models.expressions import Expression
 
+from django.contrib.gis.geos import GEOSGeometry
+from django.contrib.gis.db.models import functions as gis_functions
+
 from odata_query import ast, exceptions as ex, typing, utils, visitor
 
 from .django_q_ext import NotEqual
@@ -254,10 +257,13 @@ def visit_UnaryOp(self, node: ast.UnaryOp) -> str:
 
     def visit_Call(self, node: ast.Call) -> Union[Expression, Q]:
         ":meta private:"
+
+        func_name = node.func.full_name().replace('.', '__')
+
         try:
-            q_gen = getattr(self, "djangofunc_" + node.func.name.lower())
+            q_gen = getattr(self, "djangofunc_" + func_name.lower())
         except AttributeError:
-            raise ex.UnsupportedFunctionException(node.func.name)
+            raise ex.UnsupportedFunctionException(func_name)
 
         res = q_gen(*node.args)
         return res
@@ -303,6 +309,15 @@ def visit_CollectionLambda(self, node: ast.CollectionLambda) -> Q:
         else:
             raise NotImplementedError()
 
+    def djangofunc_geo__intersects(self, a, b):
+        return Q(**{a.name + '__' + 'intersects': GEOSGeometry(b.wkt())})
+
+    def djangofunc_geo__distance(self, a, b):
+        return gis_functions.Distance(a.name, GEOSGeometry(b.wkt()))
+
+    def djangofunc_geo__length(self, a):
+        return gis_functions.Length(a.name)
+
     def djangofunc_contains(
         self, field: ast._Node, substr: ast._Node
     ) -> lookups.Contains:

odata_query/grammar.py

@@ -53,7 +53,7 @@
     "floor": 1,
     "ceiling": 1,
     # Geo functions
-    "geo.distance": 1,
+    "geo.distance": 2,
     "geo.length": 1,
     "geo.intersects": 2,
     # Set functions
@@ -67,6 +67,7 @@ class ODataLexer(Lexer):
         "ODATA_IDENTIFIER",
         "NULL",
         "STRING",
+        "GEOGRAPHY",
         "GUID",
         "DATETIME",
         "DATE",
@@ -143,6 +144,13 @@ def STRING(self, t):
         t.value = ast.String(val)
         return t
 
+    @_(r"geography'(?:[^']|'')*'")
+    def GEOGRAPHY(self, t):
+        ":meta private:"
+
+        t.value = ast.Geography(t.value[10:-1])
+        return t
+
     @_(r"[\da-f]{8}-[\da-f]{4}-[\da-f]{4}-[\da-f]{4}-[\da-f]{12}")
     def GUID(self, t):
         ":meta private:"
@@ -375,6 +383,7 @@ def common_expr(self, p):
         "INTEGER",
         "DECIMAL",
         "STRING",
+        "GEOGRAPHY",
         "BOOLEAN",
         "GUID",
         "DATE",
@@ -551,7 +560,9 @@ def common_expr(self, p):
     ####################################################################################
     def _function_call(self, func: ast.Identifier, args: List[ast._Node]):
         ":meta private:"
-        func_name = func.name
+
+        func_name = func.full_name()
+
         try:
             n_args_exp = ODATA_FUNCTIONS[func_name]
         except KeyError:

odata_query/typing.py

@@ -64,7 +64,7 @@ def infer_return_type(node: ast.Call) -> Optional[Type[ast._Node]]:
     Returns:
         The inferred type or ``None`` if unable to infer.
     """
-    func = node.func.name
+    func = node.func.full_name()
 
     if func in (
         "contains",