Add database setup with SQLalchemy, alembic

piket_server/database/alembic.ini

@@ -0,0 +1,74 @@
+# A generic, single database configuration.
+
+[alembic]
+# path to migration scripts
+script_location = alembic
+
+# template used to generate migration files
+# file_template = %%(rev)s_%%(slug)s
+
+# timezone to use when rendering the date
+# within the migration file as well as the filename.
+# string value is passed to dateutil.tz.gettz()
+# leave blank for localtime
+# timezone =
+
+# max length of characters to apply to the
+# "slug" field
+#truncate_slug_length = 40
+
+# set to 'true' to run the environment during
+# the 'revision' command, regardless of autogenerate
+# revision_environment = false
+
+# set to 'true' to allow .pyc and .pyo files without
+# a source .py file to be detected as revisions in the
+# versions/ directory
+# sourceless = false
+
+# version location specification; this defaults
+# to alembic/versions.  When using multiple version
+# directories, initial revisions must be specified with --version-path
+# version_locations = %(here)s/bar %(here)s/bat alembic/versions
+
+# the output encoding used when revision files
+# are written from script.py.mako
+# output_encoding = utf-8
+
+sqlalchemy.url = driver://user:pass@localhost/dbname
+
+
+# Logging configuration
+[loggers]
+keys = root,sqlalchemy,alembic
+
+[handlers]
+keys = console
+
+[formatters]
+keys = generic
+
+[logger_root]
+level = WARN
+handlers = console
+qualname =
+
+[logger_sqlalchemy]
+level = WARN
+handlers =
+qualname = sqlalchemy.engine
+
+[logger_alembic]
+level = INFO
+handlers =
+qualname = alembic
+
+[handler_console]
+class = StreamHandler
+args = (sys.stderr,)
+level = NOTSET
+formatter = generic
+
+[formatter_generic]
+format = %(levelname)-5.5s [%(name)s] %(message)s
+datefmt = %H:%M:%S

piket_server/database/alembic/README

@@ -0,0 +1 @@
+Generic single-database configuration.

piket_server/database/alembic/env.py

@@ -0,0 +1,79 @@
+from __future__ import with_statement
+import os
+from alembic import context
+from sqlalchemy import engine_from_config, pool
+from logging.config import fileConfig
+
+# this is the Alembic Config object, which provides
+# access to the values within the .ini file in use.
+config = context.config
+
+# Interpret the config file for Python logging.
+# This line sets up loggers basically.
+fileConfig(config.config_file_name)
+
+# add your model's MetaData object here
+# for 'autogenerate' support
+# from myapp import mymodel
+# target_metadata = mymodel.Base.metadata
+import piket_server.database.schema
+target_metadata = piket_server.database.schema.BASE.metadata
+
+# other values from the config, defined by the needs of env.py,
+# can be acquired:
+# my_important_option = config.get_main_option("my_important_option")
+# ... etc.
+data_home = os.environ.get('XDG_DATA_HOME', '~/.local/share')
+config_dir = os.path.join(data_home, 'piket_server')
+os.makedirs(os.path.expanduser(config_dir), mode=0o744, exist_ok=True)
+db_path = os.path.expanduser(os.path.join(config_dir, 'database.sqlite3'))
+
+config.file_config['alembic']['sqlalchemy.url'] = f'sqlite:///{db_path}'
+print(config.get_main_option('sqlalchemy.url'))
+
+
+def run_migrations_offline():
+    """Run migrations in 'offline' mode.
+
+    This configures the context with just a URL
+    and not an Engine, though an Engine is acceptable
+    here as well.  By skipping the Engine creation
+    we don't even need a DBAPI to be available.
+
+    Calls to context.execute() here emit the given string to the
+    script output.
+
+    """
+    url = config.get_main_option("sqlalchemy.url")
+    context.configure(
+        url=url, target_metadata=target_metadata, literal_binds=True)
+
+    with context.begin_transaction():
+        context.run_migrations()
+
+
+def run_migrations_online():
+    """Run migrations in 'online' mode.
+
+    In this scenario we need to create an Engine
+    and associate a connection with the context.
+
+    """
+    connectable = engine_from_config(
+        config.get_section(config.config_ini_section),
+        prefix='sqlalchemy.',
+        poolclass=pool.NullPool)
+
+    with connectable.connect() as connection:
+        context.configure(
+            connection=connection,
+            target_metadata=target_metadata
+        )
+
+        with context.begin_transaction():
+            context.run_migrations()
+
+if context.is_offline_mode():
+    run_migrations_offline()
+else:
+    run_migrations_online()

piket_server/database/alembic/script.py.mako

@@ -0,0 +1,24 @@
+"""${message}
+
+Revision ID: ${up_revision}
+Revises: ${down_revision | comma,n}
+Create Date: ${create_date}
+
+"""
+from alembic import op
+import sqlalchemy as sa
+${imports if imports else ""}
+
+# revision identifiers, used by Alembic.
+revision = ${repr(up_revision)}
+down_revision = ${repr(down_revision)}
+branch_labels = ${repr(branch_labels)}
+depends_on = ${repr(depends_on)}
+
+
+def upgrade():
+    ${upgrades if upgrades else "pass"}
+
+
+def downgrade():
+    ${downgrades if downgrades else "pass"}

piket_server/database/alembic/versions/a09086bfe84c_create_persons_table.py

@@ -0,0 +1,28 @@
+"""Create persons table
+
+Revision ID: a09086bfe84c
+Revises: 
+Create Date: 2018-08-19 21:03:55.857085
+
+"""
+from alembic import op
+import sqlalchemy as sa
+
+
+# revision identifiers, used by Alembic.
+revision = 'a09086bfe84c'
+down_revision = None
+branch_labels = None
+depends_on = None
+
+
+def upgrade():
+    op.create_table(
+        'people',
+        sa.Column('person_id', sa.Integer, primary_key=True),
+        sa.Column('name', sa.String, nullable=False)
+    )
+
+
+def downgrade():
+    op.drop_table('people')

piket_server/database/schema.py

@@ -0,0 +1,20 @@
+"""
+Defines the database schema for the backend.
+"""
+
+from sqlalchemy import Column, Integer, String
+from sqlalchemy.ext.declarative import declarative_base
+
+
+BASE = declarative_base()
+
+
+class Person(BASE):
+    ''' Represents a person to be shown on the lists. '''
+    __tablename__ = 'people'
+
+    person_id = Column(Integer, primary_key=True)
+    name = Column(String, nullable=False)
+
+    def __repr__(self):
+        return f"<Person(id={self.person_id}, name={self.name})>"

setup.py

@@ -19,10 +19,6 @@ setup(
         packages=['piket_client', 'piket_server'],
 
         install_requires=[
-            'PySide2',
-            'simpleaudio',
-            'requests',
-            'Flask',
         ],
 
         extras_require={
@@ -30,6 +26,16 @@ setup(
                 'black',
                 'pylint',
             ],
+            'server': [
+                'Flask',
+                'SQLAlchemy',
+                'alembic',
+            ],
+            'client': [
+                'PySide2',
+                'simpleaudio',
+                'requests',
+            ],
         },
 
         include_package_data=True,