🐛 FIX: Skip non-columns (#2)

Skip non-columns, for instance query expressions without a data type. See https://docs.sqlalchemy.org/en/14/orm/loading_columns.html#sqlalchemy.orm.query_expression.

These column expressions raise exceptions since they did not have the attributes one would expect from a normal column. They are (usually) dynamic, and not part of the table, thus should not be included in the document generation.

Co-authored-by: Roemer Claasen <roemer@frosha.io>

Author: rclaasen

.gitignore

@@ -129,3 +129,4 @@ dmypy.json
 .pyre/
 
 .vscode/
+.idea/

.pre-commit-config.yaml

@@ -30,7 +30,7 @@ repos:
       additional_dependencies: [setuptools>=46.4.0]
 
   - repo: https://github.com/pycqa/isort
-    rev: 5.9.3
+    rev: 5.12.0
     hooks:
     - id: isort
 
@@ -41,7 +41,7 @@ repos:
       args: [--py37-plus]
 
   - repo: https://github.com/psf/black
-    rev: 21.7b0
+    rev: 23.7.0
     hooks:
     - id: black
 
@@ -57,7 +57,7 @@ repos:
       - flake8-markdown==0.2.0
 
   - repo: https://github.com/pre-commit/mirrors-mypy
-    rev: v0.910-1
+    rev: v1.4.1
     hooks:
     - id: mypy
       additional_dependencies:

sphinx_sqlalchemy/main.py

@@ -1,4 +1,5 @@
 import importlib
+import logging
 from typing import List, Optional, Set
 
 from docutils import nodes
@@ -7,7 +8,7 @@
 # from docutils.parsers.rst import directives
 from sphinx.application import Sphinx
 from sphinx.util.docutils import SphinxDirective
-from sqlalchemy import Constraint, inspect
+from sqlalchemy import Column, Constraint, inspect
 from sqlalchemy.orm.mapper import Mapper
 from sqlalchemy.sql.schema import (
     CheckConstraint,
@@ -17,6 +18,8 @@
     UniqueConstraint,
 )
 
+logger = logging.getLogger(__name__)
+
 
 def setup_extension(app: Sphinx) -> None:
     """Set up the sphinx extension."""
@@ -102,8 +105,18 @@ def add_content(self, mapper: Mapper, definition: nodes.definition) -> None:
 
         # column documentation
         if mapper.columns:
+            columns = []
+            for column in mapper.columns:
+                # Skip column expressions without a data type,
+                # eg. query_expressions. See query_expression on
+                # https://docs.sqlalchemy.org/en/14/orm/loading_columns.html
+                if not isinstance(column, Column):
+                    logger.warning(f"Skipping column '{column.name}' {type(column)}")
+                else:
+                    columns.append(column)
+
             definition += nodes.rubric(text="Columns:")
-            doc_column = any(column.doc for column in mapper.columns)
+            doc_column = any(column.doc for column in columns)
             cols = 3 if doc_column else 2
             definition += nodes.table(
                 "",
@@ -114,7 +127,7 @@ def add_content(self, mapper: Mapper, definition: nodes.definition) -> None:
                 align="left",
             )
             body = definition[-1][-1][-1]
-            for column in mapper.columns:
+            for column in columns:
                 row = nodes.row()
                 body += row
                 col_name = f"{column.name}"