ENH: Adding exchange_full to equity asset column

tests/test_assets.py

@@ -1313,6 +1313,15 @@ class TestAssetDBVersioning(ZiplineTestCase):
     def test_downgrade(self):
         # Attempt to downgrade a current assets db all the way down to v0
         conn = self.engine.connect()
+
+        # first downgrade to v3
+        downgrade(self.engine, 3)
+        metadata = sa.MetaData(conn)
+        metadata.reflect(bind=self.engine)
+        check_version_info(metadata.tables['version_info'], 3)
+        self.assertFalse('exchange_full' in metadata.tables)
+
+        # now go all the way to v0
         downgrade(self.engine, 0)
 
         # Verify that the db version is now 0

zipline/assets/asset_db_migrations.py

@@ -148,7 +148,6 @@ def _downgrade_v2(op):
 
     # Execute batch op to allow column modification in SQLite
     with op.batch_alter_table('equities') as batch_op:
-
         batch_op.drop_column('auto_close_date')
 
     # Recreate indices after batch
@@ -195,7 +194,7 @@ def _downgrade_v3(op):
     )
     op.drop_table('equities')
     op.rename_table('_new_equities', 'equities')
-    # we need to make sure the indicies have the proper names after the rename
+    # we need to make sure the indices have the proper names after the rename
     op.create_index(
         'ix_equities_company_symbol',
         'equities',
@@ -206,3 +205,25 @@ def _downgrade_v3(op):
         'equities',
         ['fuzzy_symbol'],
     )
+
+
+@downgrades(4)
+def _downgrade_v4(op):
+    """
+    Downgrades assets db by copying the `exchange_full` column to `exchange`,
+    then dropping the `exchange_full` column.
+    """
+    op.drop_index('ix_equities_fuzzy_symbol')
+    op.drop_index('ix_equities_company_symbol')
+
+    op.execute("UPDATE equities SET exchange = exchange_full")
+
+    with op.batch_alter_table('equities') as batch_op:
+        batch_op.drop_column('exchange_full')
+
+    op.create_index('ix_equities_fuzzy_symbol',
+                    table_name='equities',
+                    columns=['fuzzy_symbol'])
+    op.create_index('ix_equities_company_symbol',
+                    table_name='equities',
+                    columns=['company_symbol'])

zipline/assets/asset_db_schema.py

@@ -6,7 +6,7 @@ import sqlalchemy as sa
 # assets database
 # NOTE: When upgrading this remember to add a downgrade in:
 # .asset_db_migrations
-ASSET_DB_VERSION = 3
+ASSET_DB_VERSION = 4
 
 
 def generate_asset_db_metadata(bind=None):
@@ -55,6 +55,7 @@ def _equities_table_schema(metadata):
         sa.Column('first_traded', sa.Integer),
         sa.Column('auto_close_date', sa.Integer),
         sa.Column('exchange', sa.Text),
+        sa.Column('exchange_full', sa.Text)
     )
 
 

zipline/assets/asset_writer.py

@@ -41,7 +41,10 @@ _equities_defaults = {
     'end_date': 2 ** 62 - 1,
     'first_traded': None,
     'auto_close_date': None,
+    # the canonical exchange name, like "NYSE"
     'exchange': None,
+    # optional, something like "New York Stock Exchange"
+    'exchange_full': None,
 }
 
 # Default values for the futures DataFrame