Add support for custom SQLAlchemy dialects

AUTHORS

@@ -65,3 +65,4 @@ The following individuals have contributed code to csvkit:
 * Kev++
 * edwardros
 * Martin Burch
+* Pedro Silva

CHANGELOG

@@ -26,6 +26,7 @@ Fixes:
 * in2csv again supports nested JSON objects (fixes regression).
 * csvgrep can match multiline values.
 * csvgrep supports --no-header-row.
+* csvsql supports custom SQLAlchemy dialects.
 * csvstack supports stacking a single file.
 * FilteringCSVReader's any_match argument works correctly.
 * A file of two empty rows won't raise an error.

csvkit/sql.py

@@ -1,27 +1,17 @@
 #!/usr/bin/env python
 
 import datetime
+from pkg_resources import iter_entry_points
 
 import six
 
-from sqlalchemy import Column, MetaData, Table, create_engine
+from sqlalchemy import Column, MetaData, Table, create_engine, dialects
 from sqlalchemy import BigInteger, Boolean, Date, DateTime, Float, Integer, String, Time
 from sqlalchemy.schema import CreateTable
 
 NoneType = type(None)
 
-DIALECTS = {
-    'access': 'access.base',
-    'firebird': 'firebird.kinterbasdb',
-    'informix': 'informix.informixdb',
-    'maxdb': 'maxdb.sapdb',
-    'mssql': 'mssql.pyodbc',
-    'mysql': 'mysql.mysqlconnector',
-    'oracle': 'oracle.cx_oracle',
-    'postgresql': 'postgresql.psycopg2',
-    'sqlite': 'sqlite.pysqlite',
-    'sybase': 'sybase.pyodbc'
-}
+DIALECTS = dialects.__all__ + tuple(e.name for e in iter_entry_points('sqlalchemy.dialects'))
 
 NULL_COLUMN_MAX_LENGTH = 32
 SQL_INTEGER_MAX = 2147483647
@@ -97,8 +87,7 @@ def make_create_table_statement(sql_table, dialect=None):
     Generates a CREATE TABLE statement for a sqlalchemy table.
     """
     if dialect:
-        module = __import__('sqlalchemy.dialects.%s' % DIALECTS[dialect], fromlist=['dialect'])
-        sql_dialect = module.dialect()
+        sql_dialect = dialects.registry.load(dialect)()
     else:
         sql_dialect = None
 

tests/test_sql.py

@@ -115,6 +115,11 @@ def test_make_create_table_statement_with_schema(self):
 \tempty_column VARCHAR(32)
 );""")
 
+    def test_make_create_table_statement_with_dialects(self):
+        for dialect in sql.DIALECTS:
+            sql_table = sql.make_table(self.csv_table, 'csvsql', db_schema='test_schema')
+            statement = sql.make_create_table_statement(sql_table, dialect)
+
     def make_insert_statement(self):
         sql_table = sql.make_table(self.csv_table, 'csvsql')
         statement = sql.make_insert_statement(sql_table, self.csv_table._prepare_rows_for_serialization()[0])