Fixed #33308 -- Added support for psycopg version 3.

Thanks Simon Charette, Tim Graham, and Adam Johnson for reviews.
Co-authored-by: Florian Apolloner <florian@apolloner.eu>
Co-authored-by: Mariusz Felisiak <felisiak.mariusz@gmail.com>

django/contrib/gis/db/backends/postgis/adapter.py

@@ -1,8 +1,6 @@
 """
  This object provides quoting for GEOS geometries into PostgreSQL/PostGIS.
 """
-from psycopg2.extensions import ISQLQuote
-
 from django.contrib.gis.db.backends.postgis.pgraster import to_pgraster
 from django.contrib.gis.geos import GEOSGeometry
 from django.db.backends.postgresql.psycopg_any import sql
@@ -27,6 +25,8 @@ def __init__(self, obj, geography=False):
 
     def __conform__(self, proto):
         """Does the given protocol conform to what Psycopg2 expects?"""
+        from psycopg2.extensions import ISQLQuote
+
         if proto == ISQLQuote:
             return self
         else:

django/contrib/gis/db/backends/postgis/base.py

@@ -1,17 +1,93 @@
+from functools import lru_cache
+
 from django.db.backends.base.base import NO_DB_ALIAS
-from django.db.backends.postgresql.base import (
-    DatabaseWrapper as Psycopg2DatabaseWrapper,
-)
+from django.db.backends.postgresql.base import DatabaseWrapper as PsycopgDatabaseWrapper
+from django.db.backends.postgresql.psycopg_any import is_psycopg3
 
+from .adapter import PostGISAdapter
 from .features import DatabaseFeatures
 from .introspection import PostGISIntrospection
 from .operations import PostGISOperations
 from .schema import PostGISSchemaEditor
 
+if is_psycopg3:
+    from psycopg.adapt import Dumper
+    from psycopg.pq import Format
+    from psycopg.types import TypeInfo
+    from psycopg.types.string import TextBinaryLoader, TextLoader
+
+    class GeometryType:
+        pass
+
+    class GeographyType:
+        pass
+
+    class RasterType:
+        pass
+
+    class BaseTextDumper(Dumper):
+        def dump(self, obj):
+            # Return bytes as hex for text formatting
+            return obj.ewkb.hex().encode()
+
+    class BaseBinaryDumper(Dumper):
+        format = Format.BINARY
+
+        def dump(self, obj):
+            return obj.ewkb
+
+    @lru_cache
+    def postgis_adapters(geo_oid, geog_oid, raster_oid):
+        class BaseDumper(Dumper):
+            def __init_subclass__(cls, base_dumper):
+                super().__init_subclass__()
+
+                cls.GeometryDumper = type(
+                    "GeometryDumper", (base_dumper,), {"oid": geo_oid}
+                )
+                cls.GeographyDumper = type(
+                    "GeographyDumper", (base_dumper,), {"oid": geog_oid}
+                )
+                cls.RasterDumper = type(
+                    "RasterDumper", (BaseTextDumper,), {"oid": raster_oid}
+                )
+
+            def get_key(self, obj, format):
+                if obj.is_geometry:
+                    return GeographyType if obj.geography else GeometryType
+                else:
+                    return RasterType
+
+            def upgrade(self, obj, format):
+                if obj.is_geometry:
+                    if obj.geography:
+                        return self.GeographyDumper(GeographyType)
+                    else:
+                        return self.GeometryDumper(GeometryType)
+                else:
+                    return self.RasterDumper(RasterType)
+
+            def dump(self, obj):
+                raise NotImplementedError
+
+        class PostGISTextDumper(BaseDumper, base_dumper=BaseTextDumper):
+            pass
 
-class DatabaseWrapper(Psycopg2DatabaseWrapper):
+        class PostGISBinaryDumper(BaseDumper, base_dumper=BaseBinaryDumper):
+            format = Format.BINARY
+
+        return PostGISTextDumper, PostGISBinaryDumper
+
+
+class DatabaseWrapper(PsycopgDatabaseWrapper):
     SchemaEditorClass = PostGISSchemaEditor
 
+    _type_infos = {
+        "geometry": {},
+        "geography": {},
+        "raster": {},
+    }
+
     def __init__(self, *args, **kwargs):
         super().__init__(*args, **kwargs)
         if kwargs.get("alias", "") != NO_DB_ALIAS:
@@ -27,3 +103,45 @@ def prepare_database(self):
             if bool(cursor.fetchone()):
                 return
             cursor.execute("CREATE EXTENSION IF NOT EXISTS postgis")
+            if is_psycopg3:
+                # Ensure adapters are registers if PostGIS is used within this
+                # connection.
+                self.register_geometry_adapters(self.connection, True)
+
+    def get_new_connection(self, conn_params):
+        connection = super().get_new_connection(conn_params)
+        if is_psycopg3:
+            self.register_geometry_adapters(connection)
+        return connection
+
+    if is_psycopg3:
+
+        def _register_type(self, pg_connection, typename):
+            registry = self._type_infos[typename]
+            try:
+                info = registry[self.alias]
+            except KeyError:
+                info = TypeInfo.fetch(pg_connection, typename)
+                registry[self.alias] = info
+
+            if info:  # Can be None if the type does not exist (yet).
+                info.register(pg_connection)
+                pg_connection.adapters.register_loader(info.oid, TextLoader)
+                pg_connection.adapters.register_loader(info.oid, TextBinaryLoader)
+
+            return info.oid if info else None
+
+        def register_geometry_adapters(self, pg_connection, clear_caches=False):
+            if clear_caches:
+                for typename in self._type_infos:
+                    self._type_infos[typename].pop(self.alias, None)
+
+            geo_oid = self._register_type(pg_connection, "geometry")
+            geog_oid = self._register_type(pg_connection, "geography")
+            raster_oid = self._register_type(pg_connection, "raster")
+
+            PostGISTextDumper, PostGISBinaryDumper = postgis_adapters(
+                geo_oid, geog_oid, raster_oid
+            )
+            pg_connection.adapters.register_dumper(PostGISAdapter, PostGISTextDumper)
+            pg_connection.adapters.register_dumper(PostGISAdapter, PostGISBinaryDumper)

django/contrib/gis/db/backends/postgis/operations.py

@@ -11,6 +11,7 @@
 from django.core.exceptions import ImproperlyConfigured
 from django.db import NotSupportedError, ProgrammingError
 from django.db.backends.postgresql.operations import DatabaseOperations
+from django.db.backends.postgresql.psycopg_any import is_psycopg3
 from django.db.models import Func, Value
 from django.utils.functional import cached_property
 from django.utils.version import get_version_tuple
@@ -161,7 +162,8 @@ class PostGISOperations(BaseSpatialOperations, DatabaseOperations):
 
     unsupported_functions = set()
 
-    select = "%s::bytea"
+    select = "%s" if is_psycopg3 else "%s::bytea"
+
     select_extent = None
 
     @cached_property
@@ -407,6 +409,8 @@ def get_geometry_converter(self, expression):
         geom_class = expression.output_field.geom_class
 
         def converter(value, expression, connection):
+            if isinstance(value, str):  # Coming from hex strings.
+                value = value.encode("ascii")
             return None if value is None else GEOSGeometryBase(read(value), geom_class)
 
         return converter

django/contrib/postgres/fields/ranges.py

@@ -9,6 +9,7 @@
     NumericRange,
     Range,
 )
+from django.db.models.functions import Cast
 from django.db.models.lookups import PostgresOperatorLookup
 
 from .utils import AttributeSetter
@@ -208,7 +209,14 @@ def db_type(self, connection):
         return "daterange"
 
 
-RangeField.register_lookup(lookups.DataContains)
+class RangeContains(lookups.DataContains):
+    def get_prep_lookup(self):
+        if not isinstance(self.rhs, (list, tuple, Range)):
+            return Cast(self.rhs, self.lhs.field.base_field)
+        return super().get_prep_lookup()
+
+
+RangeField.register_lookup(RangeContains)
 RangeField.register_lookup(lookups.ContainedBy)
 RangeField.register_lookup(lookups.Overlap)
 

django/contrib/postgres/operations.py

@@ -35,6 +35,10 @@ def database_forwards(self, app_label, schema_editor, from_state, to_state):
         # installed, otherwise a subsequent data migration would use the same
         # connection.
         register_type_handlers(schema_editor.connection)
+        if hasattr(schema_editor.connection, "register_geometry_adapters"):
+            schema_editor.connection.register_geometry_adapters(
+                schema_editor.connection.connection, True
+            )
 
     def database_backwards(self, app_label, schema_editor, from_state, to_state):
         if not router.allow_migrate(schema_editor.connection.alias, app_label):

django/contrib/postgres/search.py

@@ -39,6 +39,11 @@ def db_type(self, connection):
         return "tsquery"
 
 
+class _Float4Field(Field):
+    def db_type(self, connection):
+        return "float4"
+
+
 class SearchConfig(Expression):
     def __init__(self, config):
         super().__init__()
@@ -138,7 +143,11 @@ def as_sql(self, compiler, connection, function=None, template=None):
         if clone.weight:
             weight_sql, extra_params = compiler.compile(clone.weight)
             sql = "setweight({}, {})".format(sql, weight_sql)
-        return sql, config_params + params + extra_params
+
+        # These parameters must be bound on the client side because we may
+        # want to create an index on this expression.
+        sql = connection.ops.compose_sql(sql, config_params + params + extra_params)
+        return sql, []
 
 
 class CombinedSearchVector(SearchVectorCombinable, CombinedExpression):
@@ -244,6 +253,8 @@ def __init__(
         normalization=None,
         cover_density=False,
     ):
+        from .fields.array import ArrayField
+
         if not hasattr(vector, "resolve_expression"):
             vector = SearchVector(vector)
         if not hasattr(query, "resolve_expression"):
@@ -252,6 +263,7 @@ def __init__(
         if weights is not None:
             if not hasattr(weights, "resolve_expression"):
                 weights = Value(weights)
+            weights = Cast(weights, ArrayField(_Float4Field()))
             expressions = (weights,) + expressions
         if normalization is not None:
             if not hasattr(normalization, "resolve_expression"):

django/contrib/postgres/signals.py

@@ -1,10 +1,8 @@
 import functools
 
-import psycopg2
-from psycopg2.extras import register_hstore
-
 from django.db import connections
 from django.db.backends.base.base import NO_DB_ALIAS
+from django.db.backends.postgresql.psycopg_any import is_psycopg3
 
 
 def get_type_oids(connection_alias, type_name):
@@ -32,30 +30,51 @@ def get_citext_oids(connection_alias):
     return get_type_oids(connection_alias, "citext")
 
 
-def register_type_handlers(connection, **kwargs):
-    if connection.vendor != "postgresql" or connection.alias == NO_DB_ALIAS:
-        return
-
-    oids, array_oids = get_hstore_oids(connection.alias)
-    # Don't register handlers when hstore is not available on the database.
-    #
-    # If someone tries to create an hstore field it will error there. This is
-    # necessary as someone may be using PSQL without extensions installed but
-    # be using other features of contrib.postgres.
-    #
-    # This is also needed in order to create the connection in order to install
-    # the hstore extension.
-    if oids:
-        register_hstore(
-            connection.connection, globally=True, oid=oids, array_oid=array_oids
-        )
+if is_psycopg3:
+    from psycopg.types import TypeInfo, hstore
 
-    oids, citext_oids = get_citext_oids(connection.alias)
-    # Don't register handlers when citext is not available on the database.
-    #
-    # The same comments in the above call to register_hstore() also apply here.
-    if oids:
-        array_type = psycopg2.extensions.new_array_type(
-            citext_oids, "citext[]", psycopg2.STRING
-        )
-        psycopg2.extensions.register_type(array_type, None)
+    def register_type_handlers(connection, **kwargs):
+        if connection.vendor != "postgresql" or connection.alias == NO_DB_ALIAS:
+            return
+
+        oids, array_oids = get_hstore_oids(connection.alias)
+        for oid, array_oid in zip(oids, array_oids):
+            ti = TypeInfo("hstore", oid, array_oid)
+            hstore.register_hstore(ti, connection.connection)
+
+        _, citext_oids = get_citext_oids(connection.alias)
+        for array_oid in citext_oids:
+            ti = TypeInfo("citext", 0, array_oid)
+            ti.register(connection.connection)
+
+else:
+    import psycopg2
+    from psycopg2.extras import register_hstore
+
+    def register_type_handlers(connection, **kwargs):
+        if connection.vendor != "postgresql" or connection.alias == NO_DB_ALIAS:
+            return
+
+        oids, array_oids = get_hstore_oids(connection.alias)
+        # Don't register handlers when hstore is not available on the database.
+        #
+        # If someone tries to create an hstore field it will error there. This is
+        # necessary as someone may be using PSQL without extensions installed but
+        # be using other features of contrib.postgres.
+        #
+        # This is also needed in order to create the connection in order to install
+        # the hstore extension.
+        if oids:
+            register_hstore(
+                connection.connection, globally=True, oid=oids, array_oid=array_oids
+            )
+
+        oids, citext_oids = get_citext_oids(connection.alias)
+        # Don't register handlers when citext is not available on the database.
+        #
+        # The same comments in the above call to register_hstore() also apply here.
+        if oids:
+            array_type = psycopg2.extensions.new_array_type(
+                citext_oids, "citext[]", psycopg2.STRING
+            )
+            psycopg2.extensions.register_type(array_type, None)

django/db/backends/base/features.py

@@ -164,6 +164,8 @@ class BaseDatabaseFeatures:
     # Can we roll back DDL in a transaction?
     can_rollback_ddl = False
 
+    schema_editor_uses_clientside_param_binding = False
+
     # Does it support operations requiring references rename in a transaction?
     supports_atomic_references_rename = True
 
@@ -335,6 +337,9 @@ class BaseDatabaseFeatures:
     # Does the backend support the logical XOR operator?
     supports_logical_xor = False
 
+    # Set to (exception, message) if null characters in text are disallowed.
+    prohibits_null_characters_in_text_exception = None
+
     # Collation names for use by the Django test suite.
     test_collations = {
         "ci": None,  # Case-insensitive.

django/db/backends/base/operations.py

@@ -525,6 +525,9 @@ def adapt_unknown_value(self, value):
         else:
             return value
 
+    def adapt_integerfield_value(self, value, internal_type):
+        return value
+
     def adapt_datefield_value(self, value):
         """
         Transform a date value to an object compatible with what is expected