database

app/__init__.py

@@ -1,6 +1,9 @@
 from flask import Flask
+from flask.ext.sqlalchemy import SQLAlchemy
 
 app = Flask(__name__)
 app.config.from_object('config')
+db = SQLAlchemy(app)
+
+from app import views, models
 
-from app import views

app/models.py

@@ -0,0 +1,23 @@
+from app import db
+
+ROLE_USER = 0
+ROLE_ADMIN = 1
+
+class User(db.Model):
+    id = db.Column(db.Integer, primary_key = True)
+    nickname = db.Column(db.String(64), index = True, unique = True)
+    email = db.Column(db.String(120), index = True, unique = True)
+    role = db.Column(db.SmallInteger, default = ROLE_USER)
+    posts = db.relationship('Post', backref = 'author', lazy = 'dynamic')
+    
+    def __repr__(self):
+        return '<User %r>' % (self.nickname)    
+        
+class Post(db.Model):
+    id = db.Column(db.Integer, primary_key = True)
+    body = db.Column(db.String(140))
+    timestamp = db.Column(db.DateTime)
+    user_id = db.Column(db.Integer, db.ForeignKey('user.id'))
+
+    def __repr__(self):
+        return '<Post %r>' % (self.body)

config.py

@@ -1,3 +1,6 @@
+import os
+basedir = os.path.abspath(os.path.dirname(__file__))
+
 CSRF_ENABLED = True
 SECRET_KEY = 'you-will-never-guess'
 
@@ -7,3 +10,6 @@ OPENID_PROVIDERS = [
     { 'name': 'AOL', 'url': 'http://openid.aol.com/<username>' },
     { 'name': 'Flickr', 'url': 'http://www.flickr.com/<username>' },
     { 'name': 'MyOpenID', 'url': 'https://www.myopenid.com' }]
+    
+SQLALCHEMY_DATABASE_URI = 'sqlite:///' + os.path.join(basedir, 'app.db')
+SQLALCHEMY_MIGRATE_REPO = os.path.join(basedir, 'db_repository')

db_create.py

@@ -0,0 +1,12 @@
+#!flask/bin/python
+from migrate.versioning import api
+from config import SQLALCHEMY_DATABASE_URI
+from config import SQLALCHEMY_MIGRATE_REPO
+from app import db
+import os.path
+db.create_all()
+if not os.path.exists(SQLALCHEMY_MIGRATE_REPO):
+    api.create(SQLALCHEMY_MIGRATE_REPO, 'database repository')
+    api.version_control(SQLALCHEMY_DATABASE_URI, SQLALCHEMY_MIGRATE_REPO)
+else:
+    api.version_control(SQLALCHEMY_DATABASE_URI, SQLALCHEMY_MIGRATE_REPO, api.version(SQLALCHEMY_MIGRATE_REPO))

db_downgrade.py

@@ -0,0 +1,7 @@
+#!flask/bin/python
+from migrate.versioning import api
+from config import SQLALCHEMY_DATABASE_URI
+from config import SQLALCHEMY_MIGRATE_REPO
+v = api.db_version(SQLALCHEMY_DATABASE_URI, SQLALCHEMY_MIGRATE_REPO)
+api.downgrade(SQLALCHEMY_DATABASE_URI, SQLALCHEMY_MIGRATE_REPO, v - 1)
+print 'Current database version: ' + str(api.db_version(SQLALCHEMY_DATABASE_URI, SQLALCHEMY_MIGRATE_REPO))

db_migrate.py

@@ -0,0 +1,15 @@
+#!flask/bin/python
+import imp
+from migrate.versioning import api
+from app import db
+from config import SQLALCHEMY_DATABASE_URI
+from config import SQLALCHEMY_MIGRATE_REPO
+migration = SQLALCHEMY_MIGRATE_REPO + '/versions/%03d_migration.py' % (api.db_version(SQLALCHEMY_DATABASE_URI, SQLALCHEMY_MIGRATE_REPO) + 1)
+tmp_module = imp.new_module('old_model')
+old_model = api.create_model(SQLALCHEMY_DATABASE_URI, SQLALCHEMY_MIGRATE_REPO)
+exec old_model in tmp_module.__dict__
+script = api.make_update_script_for_model(SQLALCHEMY_DATABASE_URI, SQLALCHEMY_MIGRATE_REPO, tmp_module.meta, db.metadata)
+open(migration, "wt").write(script)
+api.upgrade(SQLALCHEMY_DATABASE_URI, SQLALCHEMY_MIGRATE_REPO)
+print 'New migration saved as ' + migration
+print 'Current database version: ' + str(api.db_version(SQLALCHEMY_DATABASE_URI, SQLALCHEMY_MIGRATE_REPO))

db_repository/README

@@ -0,0 +1,4 @@
+This is a database migration repository.
+
+More information at
+http://code.google.com/p/sqlalchemy-migrate/

db_repository/manage.py

@@ -0,0 +1,5 @@
+#!/usr/bin/env python
+from migrate.versioning.shell import main
+
+if __name__ == '__main__':
+    main()

db_repository/migrate.cfg

@@ -0,0 +1,25 @@
+[db_settings]
+# Used to identify which repository this database is versioned under.
+# You can use the name of your project.
+repository_id=database repository
+
+# The name of the database table used to track the schema version.
+# This name shouldn't already be used by your project.
+# If this is changed once a database is under version control, you'll need to 
+# change the table name in each database too. 
+version_table=migrate_version
+
+# When committing a change script, Migrate will attempt to generate the 
+# sql for all supported databases; normally, if one of them fails - probably
+# because you don't have that database installed - it is ignored and the 
+# commit continues, perhaps ending successfully. 
+# Databases in this list MUST compile successfully during a commit, or the 
+# entire commit will fail. List the databases your application will actually 
+# be using to ensure your updates to that database work properly.
+# This must be a list; example: ['postgres','sqlite']
+required_dbs=[]
+
+# When creating new change scripts, Migrate will stamp the new script with
+# a version number. By default this is latest_version + 1. You can set this
+# to 'true' to tell Migrate to use the UTC timestamp instead.
+use_timestamp_numbering=False

db_repository/versions/001_migration.py

@@ -0,0 +1,28 @@
+from sqlalchemy import *
+from migrate import *
+
+
+from migrate.changeset import schema
+pre_meta = MetaData()
+post_meta = MetaData()
+user = Table('user', post_meta,
+    Column('id', Integer, primary_key=True, nullable=False),
+    Column('nickname', String(length=64)),
+    Column('email', String(length=120)),
+    Column('role', SmallInteger, default=ColumnDefault(0)),
+)
+
+
+def upgrade(migrate_engine):
+    # Upgrade operations go here. Don't create your own engine; bind
+    # migrate_engine to your metadata
+    pre_meta.bind = migrate_engine
+    post_meta.bind = migrate_engine
+    post_meta.tables['user'].create()
+
+
+def downgrade(migrate_engine):
+    # Operations to reverse the above upgrade go here.
+    pre_meta.bind = migrate_engine
+    post_meta.bind = migrate_engine
+    post_meta.tables['user'].drop()

db_repository/versions/002_migration.py

@@ -0,0 +1,28 @@
+from sqlalchemy import *
+from migrate import *
+
+
+from migrate.changeset import schema
+pre_meta = MetaData()
+post_meta = MetaData()
+post = Table('post', post_meta,
+    Column('id', Integer, primary_key=True, nullable=False),
+    Column('body', String(length=140)),
+    Column('timestamp', DateTime),
+    Column('user_id', Integer),
+)
+
+
+def upgrade(migrate_engine):
+    # Upgrade operations go here. Don't create your own engine; bind
+    # migrate_engine to your metadata
+    pre_meta.bind = migrate_engine
+    post_meta.bind = migrate_engine
+    post_meta.tables['post'].create()
+
+
+def downgrade(migrate_engine):
+    # Operations to reverse the above upgrade go here.
+    pre_meta.bind = migrate_engine
+    post_meta.bind = migrate_engine
+    post_meta.tables['post'].drop()

db_upgrade.py

@@ -0,0 +1,6 @@
+#!flask/bin/python
+from migrate.versioning import api
+from config import SQLALCHEMY_DATABASE_URI
+from config import SQLALCHEMY_MIGRATE_REPO
+api.upgrade(SQLALCHEMY_DATABASE_URI, SQLALCHEMY_MIGRATE_REPO)
+print 'Current database version: ' + str(api.db_version(SQLALCHEMY_DATABASE_URI, SQLALCHEMY_MIGRATE_REPO))