Fix Hasura Cloud, source field, printing help messages on HasuraError (#215)

* Fix printing help messages on `HasuraError`

* Lint

* Preserve sources

* Changelog

Author: droserasprout

CHANGELOG.md

@@ -8,11 +8,18 @@ Please use [this](https://docs.gitlab.com/ee/development/changelog.html) documen
 
 * cli: Fixed stacktraces missing on exception.
 * cli: Fixed wrapping `OSError` with `ConfigurationError` during config loading.
+* hasura: Fixed printing help messages on `HasuraError`.
+* hasura: Preserve list of sources in Hasura Cloud environments.
+* hasura: Fixed `HasuraConfig.source` config option.
 
 ### Changed
 
 * cli: Unknown exceptions are no longer wrapped with `DipDupError`.
 
+### Performance
+
+* hasura: Removed some useless requests.
+
 ## 4.1.0 - 2022-01-24
 
 ### Added

src/dipdup/config.py

@@ -872,11 +872,6 @@ def valid_url(cls, v):
             raise ConfigurationError(f'`{v}` is not a valid Hasura URL')
         return v.rstrip('/')
 
-    @validator('source', allow_reuse=True)
-    def valid_source(cls, v):
-        if v != 'default':
-            raise NotImplementedError('Multiple Hasura sources are not supported at the moment')
-
     @cached_property
     def headers(self) -> Dict[str, str]:
         if self.admin_secret:

src/dipdup/exceptions.py

@@ -306,6 +306,7 @@ def _help(self) -> str:
         """
 
 
+# TODO: Drop in next major version
 @dataclass(frozen=True, repr=False)
 class DeprecatedHandlerError(DipDupError):
     """Default handlers need to be converted to hooks"""
@@ -323,3 +324,17 @@ def _help(self) -> str:
               1. If you have any custom logic implemented in default handlers move it to corresponding hooks from the table above.
               2. Remove default handlers from project.
         """
+
+
+@dataclass(frozen=True, repr=False)
+class HasuraError(DipDupError):
+    """Failed to configure Hasura instance"""
+
+    msg: str
+
+    def _help(self) -> str:
+        return f"""
+            Failed to configure Hasura: {self.msg}
+
+            GraphQL integration docs: https://docs.dipdup.net/graphql/
+        """

src/dipdup/hasura.py

@@ -29,6 +29,7 @@
 from dipdup.config import HTTPConfig
 from dipdup.config import PostgresDatabaseConfig
 from dipdup.exceptions import ConfigurationError
+from dipdup.exceptions import HasuraError
 from dipdup.http import HTTPGateway
 from dipdup.models import Schema
 from dipdup.utils import iter_files
@@ -77,10 +78,6 @@ def root(self) -> str:
         return humps.decamelize(self.name)
 
 
-class HasuraError(RuntimeError):
-    ...
-
-
 class HasuraGateway(HTTPGateway):
     _default_http_config = HTTPConfig(
         cache=False,
@@ -120,21 +117,21 @@ async def configure(self, force: bool = False) -> None:
             self._logger.info('Metadata is up to date, no action required')
             return
 
-        await self._reset_metadata()
-        metadata = await self._fetch_metadata()
-
-        # NOTE: Hasura metadata updated in three steps.
-        # NOTE: Order matters because queries must be generated after applying table customization to be valid.
-        # NOTE: 1. Generate and apply tables metadata.
-        source_tables_metadata = await self._generate_source_tables_metadata()
-        metadata['sources'][0]['tables'] = source_tables_metadata
+        # NOTE: Find chosen source and overwrite its tables
+        source_name = self._hasura_config.source
+        for source in metadata['sources']:
+            if source['name'] == source_name:
+                source['tables'] = await self._generate_source_tables_metadata()
+                break
+        else:
+            raise HasuraError(f'Source `{source_name}` not found in metadata')
         await self._replace_metadata(metadata)
 
-        # NOTE: 2. Apply table customization and refresh metadata
+        # NOTE: Apply table customizations before generating queries
         await self._apply_table_customization()
         metadata = await self._fetch_metadata()
 
-        # NOTE: 3. Generate and apply queries and rest endpoints
+        # NOTE: Generate and apply queries and REST endpoints
         query_collections_metadata = await self._generate_query_collections_metadata()
         self._logger.info('Adding %s generated and user-defined queries', len(query_collections_metadata))
         metadata['query_collections'] = [
@@ -152,6 +149,7 @@ async def configure(self, force: bool = False) -> None:
 
         await self._replace_metadata(metadata)
 
+        # NOTE: Fetch metadata once again (to do: find out why is it necessary) and save its hash for future comparisons
         metadata = await self._fetch_metadata()
         metadata_hash = self._hash_metadata(metadata)
         hasura_schema.hash = metadata_hash  # type: ignore
@@ -170,7 +168,7 @@ async def _hasura_request(self, endpoint: str, json: Dict[str, Any]) -> Dict[str
         )
         self._logger.debug('Response: %s', result)
         if 'error' in result or 'errors' in result:
-            raise HasuraError('Can\'t configure Hasura instance', result)
+            raise HasuraError(result)
         return result
 
     async def _healthcheck(self) -> None:
@@ -183,7 +181,7 @@ async def _healthcheck(self) -> None:
                     break
             await asyncio.sleep(1)
         else:
-            raise HasuraError(f'Hasura instance not responding for {timeout} seconds')
+            raise HasuraError(f'Not responding for {timeout} seconds')
 
         version_json = await (
             await self._http._session.get(
@@ -192,7 +190,7 @@ async def _healthcheck(self) -> None:
         ).json()
         version = version_json['version']
         if version.startswith('v1'):
-            raise HasuraError('Hasura v1 is not supported.')
+            raise HasuraError('v1 is not supported, upgrade to the latest stable version.')
 
         self._logger.info('Connected to Hasura %s', version)
 
@@ -273,7 +271,7 @@ async def _generate_source_tables_metadata(self) -> List[Dict[str, Any]]:
             for field in model._meta.fields_map.values():
                 if isinstance(field, fields.relational.ForeignKeyFieldInstance):
                     if not isinstance(field.related_name, str):
-                        raise HasuraError(f'`related_name` of `{field}` must be set')
+                        raise HasuraError(f'`related_name` of `{field}` field must be set')
 
                     related_table_name = model_tables[field.model_name]
                     field_name = field.model_field_name
@@ -293,7 +291,7 @@ async def _generate_source_tables_metadata(self) -> List[Dict[str, Any]]:
 
                 elif isinstance(field, fields.relational.ManyToManyFieldInstance):
                     if not isinstance(field.related_name, str):
-                        raise HasuraError(f'`related_name` of `{field}` must be set')
+                        raise HasuraError(f'`related_name` of `{field}` field must be set')
 
                     related_table_name = model_tables[field.model_name]
                     junction_table_name = field.through