Decouple adapter constraints from core

core/dbt/adapters/base/impl.py

@@ -23,7 +23,7 @@
 from multiprocessing.context import SpawnContext
 
 from dbt.adapters.capability import Capability, CapabilityDict
-from dbt.contracts.graph.nodes import ColumnLevelConstraint, ConstraintType, ModelLevelConstraint
+from dbt.common.constraints import ColumnLevelConstraint, ConstraintType, ModelLevelConstraint
 
 import agate
 import pytz

core/dbt/common/constraints.py

@@ -0,0 +1,43 @@
+from dataclasses import dataclass, field
+from enum import Enum
+from typing import Optional, List
+
+from dbt.common.dataclass_schema import dbtClassMixin
+
+
+class ConstraintType(str, Enum):
+    check = "check"
+    not_null = "not_null"
+    unique = "unique"
+    primary_key = "primary_key"
+    foreign_key = "foreign_key"
+    custom = "custom"
+
+    @classmethod
+    def is_valid(cls, item) -> bool:
+        try:
+            cls(item)
+        except ValueError:
+            return False
+        return True
+
+
+@dataclass
+class ColumnLevelConstraint(dbtClassMixin):
+    type: ConstraintType
+    name: Optional[str] = None
+    # expression is a user-provided field that will depend on the constraint type.
+    # It could be a predicate (check type), or a sequence sql keywords (e.g. unique type),
+    # so the vague naming of 'expression' is intended to capture this range.
+    expression: Optional[str] = None
+    warn_unenforced: bool = (
+        True  # Warn if constraint cannot be enforced by platform but will be in DDL
+    )
+    warn_unsupported: bool = (
+        True  # Warn if constraint is not supported by the platform and won't be in DDL
+    )
+
+
+@dataclass
+class ModelLevelConstraint(ColumnLevelConstraint):
+    columns: List[str] = field(default_factory=list)

core/dbt/contracts/graph/nodes.py

@@ -2,12 +2,12 @@
 from datetime import datetime
 import time
 from dataclasses import dataclass, field
-from enum import Enum
 import hashlib
 
 from mashumaro.types import SerializableType
 from typing import Optional, Union, List, Dict, Any, Sequence, Tuple, Iterator, Literal
 
+from dbt.common.constraints import ColumnLevelConstraint, ConstraintType, ModelLevelConstraint
 from dbt.common.dataclass_schema import dbtClassMixin, ExtensibleDbtClassMixin
 
 from dbt.clients.system import write_file
@@ -178,44 +178,6 @@ def keyword_args(self) -> Dict[str, Optional[NodeVersion]]:
             return {}
 
 
-class ConstraintType(str, Enum):
-    check = "check"
-    not_null = "not_null"
-    unique = "unique"
-    primary_key = "primary_key"
-    foreign_key = "foreign_key"
-    custom = "custom"
-
-    @classmethod
-    def is_valid(cls, item):
-        try:
-            cls(item)
-        except ValueError:
-            return False
-        return True
-
-
-@dataclass
-class ColumnLevelConstraint(dbtClassMixin):
-    type: ConstraintType
-    name: Optional[str] = None
-    # expression is a user-provided field that will depend on the constraint type.
-    # It could be a predicate (check type), or a sequence sql keywords (e.g. unique type),
-    # so the vague naming of 'expression' is intended to capture this range.
-    expression: Optional[str] = None
-    warn_unenforced: bool = (
-        True  # Warn if constraint cannot be enforced by platform but will be in DDL
-    )
-    warn_unsupported: bool = (
-        True  # Warn if constraint is not supported by the platform and won't be in DDL
-    )
-
-
-@dataclass
-class ModelLevelConstraint(ColumnLevelConstraint):
-    columns: List[str] = field(default_factory=list)
-
-
 @dataclass
 class ColumnInfo(AdditionalPropertiesMixin, ExtensibleDbtClassMixin, Replaceable):
     """Used in all ManifestNodes and SourceDefinition"""

core/dbt/parser/common.py

@@ -1,3 +1,4 @@
+from dbt.common.constraints import ColumnLevelConstraint, ConstraintType
 from dbt.contracts.graph.unparsed import (
     HasColumnProps,
     UnparsedColumn,
@@ -8,12 +9,7 @@
     UnparsedModelUpdate,
 )
 from dbt.contracts.graph.unparsed import NodeVersion, HasColumnTests, HasColumnDocs
-from dbt.contracts.graph.nodes import (
-    UnpatchedSourceDefinition,
-    ColumnInfo,
-    ColumnLevelConstraint,
-    ConstraintType,
-)
+from dbt.contracts.graph.nodes import UnpatchedSourceDefinition, ColumnInfo
 from dbt.parser.search import FileBlock
 from typing import List, Dict, Any, TypeVar, Generic, Union, Optional
 from dataclasses import dataclass

core/dbt/parser/schemas.py

@@ -5,6 +5,7 @@
 from typing import Any, Callable, Dict, Generic, Iterable, List, Optional, Type, TypeVar
 from dataclasses import dataclass, field
 
+from dbt.common.constraints import ConstraintType, ModelLevelConstraint
 from dbt.common.dataclass_schema import ValidationError, dbtClassMixin
 
 from dbt.clients.yaml_helper import load_yaml_text
@@ -17,9 +18,7 @@
     ParsedNodePatch,
     ParsedMacroPatch,
     UnpatchedSourceDefinition,
-    ConstraintType,
     ModelNode,
-    ModelLevelConstraint,
 )
 from dbt.contracts.graph.unparsed import (
     HasColumnDocs,

plugins/postgres/dbt/adapters/postgres/impl.py

@@ -9,9 +9,9 @@
 from dbt.adapters.postgres import PostgresConnectionManager
 from dbt.adapters.postgres.column import PostgresColumn
 from dbt.adapters.postgres import PostgresRelation
+from dbt.common.constraints import ConstraintType
 from dbt.common.dataclass_schema import dbtClassMixin, ValidationError
 from dbt.common.exceptions import DbtRuntimeError
-from dbt.contracts.graph.nodes import ConstraintType
 from dbt.adapters.exceptions import (
     CrossDbReferenceProhibitedError,
     IndexConfigNotDictError,