sources.csv: Allow CSV files as data sources in beanquery.connect()

beanquery/query_execute_test.py

@@ -1855,3 +1855,18 @@ def test_create_table_guess_types(self, filename):
         self.assertEqual(names, ['id', 'name', 'check', 'date', 'value'])
         types = [column.dtype for column in self.conn.tables['test'].columns.values()]
         self.assertEqual(types, [int, str, bool, datetime.date, Decimal])
+
+
+class TestCSVSource(unittest.TestCase):
+
+    @docfile
+    def test_csv_source(self, filename):
+        '''\
+        id, name, check, date, value
+        1234, one, true, 2025-01-01, 1.234
+        '''
+        conn = beanquery.connect(f'csv:{filename}?name=test')
+        names = list(conn.tables['test'].columns.keys())
+        self.assertEqual(names, ['id', 'name', 'check', 'date', 'value'])
+        types = [column.dtype for column in conn.tables['test'].columns.values()]
+        self.assertEqual(types, [int, str, bool, datetime.date, Decimal])

beanquery/sources/csv.py

@@ -1,6 +1,7 @@
 import csv
 import datetime
 
+from os import path
 from urllib.parse import urlparse, parse_qsl
 
 from beanquery import tables
@@ -91,3 +92,14 @@ def create(name, columns, using):
     if filename:
         data = open(filename, encoding=encoding)
     return Table(name, columns, data, header=header, **params)
+
+
+def attach(context, dsn, *, data=None):
+    parts = urlparse(dsn)
+    filename = parts.path
+    params = dict(parse_qsl(parts.query))
+    encoding = params.pop('encoding', None)
+    if filename:
+        data = open(filename, encoding=encoding)
+    name = params.pop('name', None) or path.splitext(path.basename(filename))[0] or 'csv'
+    context.tables[name] = Table(name, None, data, header=True, **params)