Fix docs generation for cross-db sources in REDSHIFT RA3 node (#3408)

* Fix docs generating for cross-db sources

* Code reorganization

* Code adjustments according to flake8

* Error message adjusted to be more precise

* CHANGELOG update

CHANGELOG.md

@@ -1,3 +1,15 @@
+## dbt 0.21.0
+
+### Features
+
+### Fixes
+- Fix docs generation for cross-db sources in REDSHIFT RA3 node ([#3236](https:/fishtown-analytics/dbt/issues/3236), [#3408](https:/fishtown-analytics/dbt/pull/3408))
+
+### Under the hood
+
+Contributors:
+- [@kostek-pl](https:/kostek-pl) ([#3236](https:/fishtown-analytics/dbt/pull/3408))
+
 ## dbt 0.20.0 (Release TBD)
 
 ## dbt 0.20.0rc1 (June 04, 2021)

core/dbt/adapters/base/relation.py

@@ -433,13 +433,14 @@ def search(
  for schema in schemas:
  yield information_schema_name, schema
 
- def flatten(self):
+ def flatten(self, allow_multiple_databases: bool = False):
  new = self.__class__()
 
- # make sure we don't have duplicates
- seen = {r.database.lower() for r in self if r.database}
- if len(seen) > 1:
- dbt.exceptions.raise_compiler_error(str(seen))
+ # make sure we don't have multiple databases if allow_multiple_databases is set to False
+ if not allow_multiple_databases:
+ seen = {r.database.lower() for r in self if r.database}
+ if len(seen) > 1:
+ dbt.exceptions.raise_compiler_error(str(seen))
 
  for information_schema_name, schema in self.search():
  path = {

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

@@ -112,7 +112,7 @@ def _link_cached_database_relations(self, schemas: Set[str]):
  self.cache.add_link(referenced, dependent)
 
  def _get_catalog_schemas(self, manifest):
- # postgres/redshift only allow one database (the main one)
+ # postgres only allow one database (the main one)
  schemas = super()._get_catalog_schemas(manifest)
  try:
  return schemas.flatten()

plugins/redshift/dbt/adapters/redshift/connections.py

@@ -49,6 +49,7 @@ class RedshiftCredentials(PostgresCredentials):
  keepalives_idle: int = 240
  autocreate: bool = False
  db_groups: List[str] = field(default_factory=list)
+ ra3_node: Optional[bool] = False
 
  @property
  def type(self):

plugins/redshift/dbt/adapters/redshift/impl.py

@@ -1,11 +1,14 @@
 from dataclasses import dataclass
 from typing import Optional
 from dbt.adapters.base.impl import AdapterConfig
+from dbt.adapters.sql import SQLAdapter
+from dbt.adapters.base.meta import available
 from dbt.adapters.postgres import PostgresAdapter
 from dbt.adapters.redshift import RedshiftConnectionManager
 from dbt.adapters.redshift import RedshiftColumn
 from dbt.adapters.redshift import RedshiftRelation
 from dbt.logger import GLOBAL_LOGGER as logger # noqa
+import dbt.exceptions
 
 
 @dataclass
@@ -16,7 +19,7 @@ class RedshiftConfig(AdapterConfig):
  bind: Optional[bool] = None
 
 
-class RedshiftAdapter(PostgresAdapter):
+class RedshiftAdapter(PostgresAdapter, SQLAdapter):
  Relation = RedshiftRelation
  ConnectionManager = RedshiftConnectionManager
  Column = RedshiftColumn
@@ -57,3 +60,29 @@ def convert_text_type(cls, agate_table, col_idx):
  @classmethod
  def convert_time_type(cls, agate_table, col_idx):
  return "varchar(24)"
+
+ @available
+ def verify_database(self, database):
+ if database.startswith('"'):
+ database = database.strip('"')
+ expected = self.config.credentials.database
+ ra3_node = self.config.credentials.ra3_node
+
+ if database.lower() != expected.lower() and not ra3_node:
+ raise dbt.exceptions.NotImplementedException(
+ 'Cross-db references allowed only in RA3.* node. ({} vs {})'
+ .format(database, expected)
+ )
+ # return an empty string on success so macros can call this
+ return ''
+
+ def _get_catalog_schemas(self, manifest):
+ # redshift(besides ra3) only allow one database (the main one)
+ schemas = super(SQLAdapter, self)._get_catalog_schemas(manifest)
+ try:
+ return schemas.flatten(allow_multiple_databases=self.config.credentials.ra3_node)
+ except dbt.exceptions.RuntimeException as exc:
+ dbt.exceptions.raise_compiler_error(
+ 'Cross-db references allowed only in {} RA3.* node. Got {}'
+ .format(self.type(), exc.msg)
+ )