Plugin baselines skip tables that already exist

plugins/tools/migrations/versions/0001_securesend_baseline.py

@@ -12,6 +12,11 @@ plugin's tables, so the foreign key to the core users table cannot resolve at
 CreateTable-compile time.
 """
 from alembic import op
+
+from shopdb.plugins.alembic_template import (
+    create_index_if_missing,
+    create_table_if_missing,
+)
 import sqlalchemy as sa
 
 
@@ -23,7 +28,7 @@ depends_on = None
 
 
 def upgrade():
-    op.create_table(
+    create_table_if_missing(
         'securesendsecrets',
         sa.Column('secretid', sa.Integer(), nullable=False),
         # 128 bits of randomness as hex. With no login on the read side this is
@@ -47,13 +52,13 @@ def upgrade():
     )
     # Unique, because the token is looked up on every read and two rows sharing
     # one would make a link ambiguous.
-    op.create_index('ixsecuresendsecretstoken', 'securesendsecrets',
-                    ['token'], unique=True)
+    create_index_if_missing('ixsecuresendsecretstoken', 'securesendsecrets',
+                            ['token'], unique=True)
     # Expiry sweeps scan on this.
-    op.create_index('ixsecuresendsecretsexpiresat', 'securesendsecrets',
-                    ['expiresat'])
-    op.create_index('ixsecuresendsecretscreatedby', 'securesendsecrets',
-                    ['createdbyuserid'])
+    create_index_if_missing('ixsecuresendsecretsexpiresat', 'securesendsecrets',
+                            ['expiresat'])
+    create_index_if_missing('ixsecuresendsecretscreatedby', 'securesendsecrets',
+                            ['createdbyuserid'])
 
 
 def downgrade():