add --declarative option to create_model to generate new declarative style

migrate/versioning/api.py

@@ -284,7 +284,8 @@ def create_model(url,repository,**opts):
     NOTE: This is EXPERIMENTAL.
     """  # TODO: get rid of EXPERIMENTAL label
     engine=create_engine(url)
-    print cls_schema.create_model(engine,repository)
+    declarative = opts.get('declarative', False)
+    print cls_schema.create_model(engine,repository,declarative)
 
 def make_update_script_for_model(url,oldmodel,model,repository,**opts):
     """%prog make_update_script_for_model URL OLDMODEL MODEL REPOSITORY_PATH

migrate/versioning/genmodel.py

@@ -13,10 +13,20 @@ from sqlalchemy import *
 meta = MetaData()
 """
 
+DECLARATIVE_HEADER = """
+## File autogenerated by genmodel.py
+
+from sqlalchemy import *
+from sqlalchemy.ext import declarative
+
+Base = declarative.declarative_base()
+"""
+
 class ModelGenerator(object):
 
-    def __init__(self, diff):
+    def __init__(self, diff, declarative=False):
         self.diff = diff
+        self.declarative = declarative
         dialectModule = sys.modules[self.diff.conn.dialect.__module__]  # is there an easier way to get this?
         self.colTypeMappings = dict( (v,k) for k,v in dialectModule.colspecs.items() )
     
@@ -59,21 +69,36 @@ class ModelGenerator(object):
         else:
             data['maybeComma'] = ''
 
-        return """Column(%(name)r, %(type)r %(maybeComma)s %(constraints)s %(args)s)""" % data
+        commonStuff = " %(maybeComma)s %(constraints)s %(args)s)""" % data
+        commonStuff = commonStuff.strip()
+        data['commonStuff'] = commonStuff
+        if self.declarative:
+            return """%(name)s = Column(%(type)r%(commonStuff)s""" % data
+        else:
+            return """Column(%(name)r, %(type)r%(commonStuff)s""" % data
     
     def getTableDefn(self, table):
         out = []
         tableName = table.name
-        out.append("%(table)s = Table('%(table)s', meta," % {'table': tableName})
-        for col in table.columns:
-            out.append("  %s," % self.column_repr(col))
-        out.append(")")
+        if self.declarative:
+            out.append("class %(table)s(Base):" % {'table': tableName})
+            out.append("  __tablename__ = '%(table)s'" % {'table': tableName})
+            for col in table.columns:
+                out.append("  %s" % self.column_repr(col))
+        else:
+            out.append("%(table)s = Table('%(table)s', meta," % {'table': tableName})
+            for col in table.columns:
+                out.append("  %s," % self.column_repr(col))
+            out.append(")")
         return out
         
     def toPython(self):
         ''' Assume database is current and model is empty. '''
         out = []
-        out.append(HEADER)
+        if self.declarative:
+            out.append(DECLARATIVE_HEADER)
+        else:
+            out.append(HEADER)
         out.append("")
         for table in self.diff.tablesMissingInModel:
             out.extend(self.getTableDefn(table))

migrate/versioning/schema.py

@@ -112,13 +112,13 @@ class ControlledSchema(object):
         return diff
 
     @classmethod
-    def create_model(cls,engine,repository):
+    def create_model(cls,engine,repository,declarative=False):
         """Dump the current database as a Python model."""
 
         if isinstance(repository, basestring):
             repository=Repository(repository)
         diff = schemadiff.getDiffOfModelAgainstDatabase(MetaData(), engine, excludeTables=[repository.version_table])
-        return genmodel.ModelGenerator(diff).toPython()
+        return genmodel.ModelGenerator(diff, declarative).toPython()
     
     def update_db_from_model(self,model):
         """Modify the database to match the structure of the current Python model."""