Adds check columns operation

digital_land/expectations/operation.py

@@ -186,3 +186,41 @@ def count_deleted_entities(
     }
 
     return result, message, details
+
+
+def check_columns(conn, expected: dict):
+    # This operation checks that the db connection provided contains the tables with the expected columns provided
+
+    # expected: a dictionary containing table names as keys, with a list of their expected columns as the value
+
+    details = []
+    success_count = 0
+    failure_count = 0
+    for k, v in expected.items():
+        table_name = k
+        expected_columns = v
+        sql = f"""
+        PRAGMA table_info({table_name})
+        """
+        rows = conn.execute(sql).fetchall()
+        actual = [row[1] for row in rows]
+        success = set(expected_columns).issubset(set(actual))
+        missing = list(set(expected_columns) - set(actual))
+        details.append(
+            {
+                "table": table_name,
+                "success": success,
+                "missing": missing,
+                "actual": actual,
+                "expected": expected_columns,
+            }
+        )
+        if success:
+            success_count += 1
+        else:
+            failure_count += 1
+
+    result = False if failure_count > 0 else True
+    message = f"{success_count} out of {success_count + failure_count} tables had expected columns"
+
+    return result, message, details

tests/integration/expectations/test_operation.py

@@ -1,8 +1,10 @@
 import spatialite
+import sqlite3
 import pytest
 import pandas as pd
 
 from digital_land.expectations.operation import (
+    check_columns,
     count_lpa_boundary,
     count_deleted_entities,
 )
@@ -174,3 +176,67 @@ def test_count_deleted_entities(dataset_path, mocker):
     for key in detail_keys:
         assert key in details, f"{key} missing from details"
     assert "1002" in details["entities"]
+
+
+def test_check_columns(dataset_path):
+    expected = {
+        "entity": [
+            "dataset",
+            "end_date",
+            "entity",
+            "entry_date",
+            "geojson",
+            "geometry",
+            "json",
+            "name",
+            "organisation_entity",
+            "point",
+            "prefix",
+            "reference",
+            "start_date",
+            "typology",
+        ],
+        "old_entity": ["old_entity", "entity"],
+    }
+
+    with sqlite3.connect(dataset_path) as conn:
+        result, message, details = check_columns(conn.cursor(), expected)
+
+        assert result
+        assert "2 out of 2 tables had expected columns" in message
+
+        assert details[0]["table"] == "entity"
+        assert any(x in details[0]["actual"] for x in expected["entity"])
+        assert any(x in details[0]["expected"] for x in expected["entity"])
+
+
+def test_check_columns_failure(dataset_path):
+    expected = {
+        "entity": [
+            "missing",
+            "columns",
+            "dataset",
+            "end_date",
+            "entity",
+            "entry_date",
+            "geojson",
+            "geometry",
+            "json",
+            "name",
+            "organisation_entity",
+            "point",
+            "prefix",
+            "reference",
+            "start_date",
+            "typology",
+        ],
+        "old_entity": ["old_entity", "entity"],
+    }
+
+    with sqlite3.connect(dataset_path) as conn:
+        result, message, details = check_columns(conn.cursor(), expected)
+        assert not result
+        assert "1 out of 2 tables had expected columns" in message
+        assert not details[0]["success"]
+        assert "missing" in details[0]["missing"]
+        assert "columns" in details[0]["missing"]