[BACKPORT] Improve warning for constraints and mat types (#7806)

* Improve warnings for constraints and materialization types (#7696)

* first pass

* debugging

* regen proto types

* refactor to use warn_supported flag

* PR feedback

* regen proto files after conflicts

* fix problems wqith conflict resolution

.changes/unreleased/Fixes-20230525-073651.yaml

@@ -0,0 +1,6 @@
+kind: Fixes
+body: Improve warnings for constraints and materialization types
+time: 2023-05-25T07:36:51.855641-05:00
+custom:
+  Author: emmyoop
+  Issue: "7335"

core/dbt/events/types.proto

@@ -1182,6 +1182,16 @@ message UnpinnedRefNewVersionAvailableMsg {
     UnpinnedRefNewVersionAvailable data = 2;
 }
 
+// I068
+message UnsupportedConstraintMaterialization {
+    string materialized = 1;
+}
+
+message UnsupportedConstraintMaterializationMsg {
+    EventInfo info = 1;
+    UnsupportedConstraintMaterialization data = 2;
+}
+
 // M - Deps generation
 
 // M001

core/dbt/events/types.py

@@ -1148,6 +1148,19 @@ def message(self) -> str:
         return msg
 
 
+class UnsupportedConstraintMaterialization(WarnLevel):
+    def code(self):
+        return "I068"
+
+    def message(self) -> str:
+        msg = (
+            f"Constraint types are not supported for {self.materialized} materializations and will "
+            "be ignored.  Set 'warn_unsupported: false' on this constraint to ignore this warning."
+        )
+
+        return line_wrap_message(warning_tag(msg))
+
+
 # =======================================================
 # M - Deps generation
 # =======================================================

core/dbt/parser/schemas.py

@@ -76,8 +76,13 @@
     YamlParseListError,
 )
 from dbt.events.functions import warn_or_error
-from dbt.events.types import WrongResourceSchemaFile, NoNodeForYamlKey, MacroNotFoundForPatch
 from dbt.node_types import NodeType
+from dbt.events.types import (
+    MacroNotFoundForPatch,
+    NoNodeForYamlKey,
+    UnsupportedConstraintMaterialization,
+    WrongResourceSchemaFile,
+)
 from dbt.parser.base import SimpleParser
 from dbt.parser.search import FileBlock
 from dbt.parser.generic_test_builders import (
@@ -1014,23 +1019,39 @@ def patch_constraints(self, node, constraints):
             node.constraints = [ModelLevelConstraint.from_dict(c) for c in constraints]
 
     def _validate_constraint_prerequisites(self, model_node: ModelNode):
+
+        column_warn_unsupported = [
+            constraint.warn_unsupported
+            for column in model_node.columns.values()
+            for constraint in column.constraints
+        ]
+        model_warn_unsupported = [
+            constraint.warn_unsupported for constraint in model_node.constraints
+        ]
+        warn_unsupported = column_warn_unsupported + model_warn_unsupported
+
+        # if any constraint has `warn_unsupported` as True then send the warning
+        if any(warn_unsupported) and model_node.config.materialized not in [
+            "table",
+            "incremental",
+        ]:
+            warn_or_error(
+                UnsupportedConstraintMaterialization(materialized=model_node.config.materialized),
+                node=model_node,
+            )
+
         errors = []
         if not model_node.columns:
             errors.append(
                 "Constraints must be defined in a `yml` schema configuration file like `schema.yml`."
             )
 
-        if model_node.config.materialized not in ["table", "view", "incremental"]:
-            errors.append(
-                f"Only table, view, and incremental materializations are supported for constraints, but found '{model_node.config.materialized}'"
-            )
-
         if str(model_node.language) != "sql":
             errors.append(f"Language Error: Expected 'sql' but found '{model_node.language}'")
 
         if errors:
             raise ParsingError(
-                f"Constraint validation failed for: ({model_node.original_file_path})\n"
+                f"Contract enforcement failed for: ({model_node.original_file_path})\n"
                 + "\n".join(errors)
             )
 

tests/functional/configs/test_contract_configs.py

@@ -1,6 +1,7 @@
 import pytest
+import os
 from dbt.exceptions import ParsingError, ValidationError
-from dbt.tests.util import run_dbt, get_manifest, get_artifact, run_dbt_and_capture
+from dbt.tests.util import run_dbt, get_manifest, get_artifact, run_dbt_and_capture, write_file
 
 my_model_sql = """
 {{
@@ -56,10 +57,10 @@
   cast('2019-01-01' as date) as date_day
 """
 
-my_ephemeral_model_sql = """
+my_view_model_sql = """
 {{
   config(
-    materialized = "ephemeral"
+    materialized = "view"
   )
 }}
 
@@ -108,6 +109,34 @@ def model(dbt, _):
         data_type: date
 """
 
+model_schema_ignore_unsupported_yml = """
+version: 2
+models:
+  - name: my_model
+    config:
+      contract:
+        enforced: true
+    columns:
+      - name: id
+        quote: true
+        data_type: integer
+        description: hello
+        constraints:
+            - type: not_null
+              warn_unsupported: False
+            - type: primary_key
+              warn_unsupported: False
+            - type: check
+              warn_unsupported: False
+              expression: (id > 0)
+        tests:
+          - unique
+      - name: color
+        data_type: text
+      - name: date_day
+        data_type: date
+"""
+
 model_schema_errors_yml = """
 version: 2
 models:
@@ -367,22 +396,49 @@ class TestModelLevelConstraintsErrorMessages:
     @pytest.fixture(scope="class")
     def models(self):
         return {
-            "my_model.sql": my_ephemeral_model_sql,
-            "constraints_schema.yml": model_schema_errors_yml,
+            "my_model.py": my_model_python_error,
+            "constraints_schema.yml": model_schema_yml,
         }
 
     def test__config_errors(self, project):
         with pytest.raises(ParsingError) as err_info:
             run_dbt(["run"], expect_pass=False)
 
         exc_str = " ".join(str(err_info.value).split())
-        expected_materialization_error = "Only table, view, and incremental materializations are supported for constraints, but found 'ephemeral'"
+        expected_materialization_error = "Language Error: Expected 'sql' but found 'python'"
         assert expected_materialization_error in str(exc_str)
         # This is a compile time error and we won't get here because the materialization check is parse time
         expected_empty_data_type_error = "Columns with `data_type` Blank/Null not allowed on contracted models. Columns Blank/Null: ['date_day']"
         assert expected_empty_data_type_error not in str(exc_str)
 
 
+class TestModelLevelConstraintsWarningMessages:
+    @pytest.fixture(scope="class")
+    def models(self):
+        return {
+            "my_model.sql": my_view_model_sql,
+            "constraints_schema.yml": model_schema_yml,
+        }
+
+    def test__config_warning(self, project):
+        _, log_output = run_dbt_and_capture(["run"])
+
+        expected_materialization_warning = (
+            "Constraint types are not supported for view materializations"
+        )
+        assert expected_materialization_warning in str(log_output)
+
+        # change to not show warnings, message should not be in logs
+        models_dir = os.path.join(project.project_root, "models")
+        write_file(model_schema_ignore_unsupported_yml, models_dir, "constraints_schema.yml")
+        _, log_output = run_dbt_and_capture(["run"])
+
+        expected_materialization_warning = (
+            "Constraint types are not supported for view materializations"
+        )
+        assert expected_materialization_warning not in str(log_output)
+
+
 class TestSchemaContractEnabledConfigs:
     @pytest.fixture(scope="class")
     def models(self):

tests/unit/test_events.py

@@ -232,6 +232,7 @@ def test_event_codes(self):
     types.UnpinnedRefNewVersionAvailable(
         ref_node_name="", ref_node_package="", ref_node_version="", ref_max_version=""
     ),
+    types.UnsupportedConstraintMaterialization(materialized=""),
     # M - Deps generation ======================
     types.GitSparseCheckoutSubdirectory(subdir=""),
     types.GitProgressCheckoutRevision(revision=""),