.gitignore

@@ -2,5 +2,5 @@ gitea/
 .env
 pmb-pf/
 venv
-
+zapp.db
 

backend/README.md

@@ -1,8 +1,23 @@
 
-*pip:\
+pip:
+
 
 ```
 pip install flask
 pip install python-dotenv
 pip install flask-wtf
+pip install flask-sqlalchemy
+pip install flask-migrate
+pip freeze > requirements.txt
 ```
+
+db:
+
+```
+flask db migrate -m "users table"
+flask db upgrade
+
+flask db downgrade [base]
+flask db upgrade
+```
+

backend/app/__init__.py

@@ -1,8 +1,12 @@
 from flask import Flask
 from config import Config
+from flask_sqlalchemy import SQLAlchemy
+from flask_migrate import Migrate
 
 app = Flask(__name__)
 app.config.from_object(Config)
+db = SQLAlchemy(app)
+migrate = Migrate(app, db)
 
-from app import routes
+from app import routes, models
 

backend/app/models.py

@@ -0,0 +1,27 @@
+from datetime import datetime, timezone
+from typing import Optional
+import sqlalchemy as sa
+import sqlalchemy.orm as so
+from app import db
+
+class User(db.Model):
+    id: so.Mapped[int] = so.mapped_column(primary_key=True)
+    username: so.Mapped[str] = so.mapped_column(sa.String(64), index=True, unique=True)
+    email: so.Mapped[str] = so.mapped_column(sa.String(120), index=True, unique=True)
+    password_hash: so.Mapped[Optional[str]] = so.mapped_column(sa.String(256))
+    posts: so.WriteOnlyMapped['Post'] = so.relationship(back_populates='author')
+
+    def __repr__(self):
+        return '<User {}>'.format(self.username)
+
+class Post(db.Model):
+    id: so.Mapped[int] = so.mapped_column(primary_key=True)
+    body: so.Mapped[str] = so.mapped_column(sa.String(140))
+    timestamp: so.Mapped[datetime] = so.mapped_column(index=True, default=lambda: datetime.now(timezone.utc))
+    user_id: so.Mapped[int] = so.mapped_column(sa.ForeignKey(User.id), index=True)
+    author: so.Mapped[User] = so.relationship(back_populates='posts')
+
+    def __repr__(self):
+        return '<Post {}>'.format(self.body)
+
+

backend/config.py

@@ -1,7 +1,11 @@
 import os
+basedir = os.path.abspath(os.path.dirname(__file__))
 
 # Remove or fallbacks for prod
 
 class Config:
     SECRET_KEY = os.environ.get('FLASK_SECRET_KEY') or 'flasksk'
+    SQLALCHEMY_DATABASE_URI = 'sqlite:///' + os.path.join(basedir, 'zapp.db')
+    #SQLALCHEMY_DATABASE_URI = 'db'
+
 

backend/microblog.py

@@ -1,2 +1,10 @@
-from app import app
+import sqlalchemy as sa
+import sqlalchemy.orm as so
+from app import app, db
+from app.models import User, Post
+
+@app.shell_context_processor
+def make_shell_context():
+    return {'sa': sa, 'so': so, 'db': db, 'User': User, 'Post': Post}
+
 

backend/migrations/README

@@ -0,0 +1 @@
+Single-database configuration for Flask.

backend/migrations/alembic.ini

@@ -0,0 +1,50 @@
+# A generic, single database configuration.
+
+[alembic]
+# template used to generate migration files
+# file_template = %%(rev)s_%%(slug)s
+
+# set to 'true' to run the environment during
+# the 'revision' command, regardless of autogenerate
+# revision_environment = false
+
+
+# Logging configuration
+[loggers]
+keys = root,sqlalchemy,alembic,flask_migrate
+
+[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
+
+[logger_flask_migrate]
+level = INFO
+handlers =
+qualname = flask_migrate
+
+[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

backend/migrations/env.py

@@ -0,0 +1,113 @@
+import logging
+from logging.config import fileConfig
+
+from flask import current_app
+
+from alembic import context
+
+# 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)
+logger = logging.getLogger('alembic.env')
+
+
+def get_engine():
+    try:
+        # this works with Flask-SQLAlchemy<3 and Alchemical
+        return current_app.extensions['migrate'].db.get_engine()
+    except (TypeError, AttributeError):
+        # this works with Flask-SQLAlchemy>=3
+        return current_app.extensions['migrate'].db.engine
+
+
+def get_engine_url():
+    try:
+        return get_engine().url.render_as_string(hide_password=False).replace(
+            '%', '%%')
+    except AttributeError:
+        return str(get_engine().url).replace('%', '%%')
+
+
+# add your model's MetaData object here
+# for 'autogenerate' support
+# from myapp import mymodel
+# target_metadata = mymodel.Base.metadata
+config.set_main_option('sqlalchemy.url', get_engine_url())
+target_db = current_app.extensions['migrate'].db
+
+# 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.
+
+
+def get_metadata():
+    if hasattr(target_db, 'metadatas'):
+        return target_db.metadatas[None]
+    return target_db.metadata
+
+
+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=get_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.
+
+    """
+
+    # this callback is used to prevent an auto-migration from being generated
+    # when there are no changes to the schema
+    # reference: http://alembic.zzzcomputing.com/en/latest/cookbook.html
+    def process_revision_directives(context, revision, directives):
+        if getattr(config.cmd_opts, 'autogenerate', False):
+            script = directives[0]
+            if script.upgrade_ops.is_empty():
+                directives[:] = []
+                logger.info('No changes in schema detected.')
+
+    conf_args = current_app.extensions['migrate'].configure_args
+    if conf_args.get("process_revision_directives") is None:
+        conf_args["process_revision_directives"] = process_revision_directives
+
+    connectable = get_engine()
+
+    with connectable.connect() as connection:
+        context.configure(
+            connection=connection,
+            target_metadata=get_metadata(),
+            **conf_args
+        )
+
+        with context.begin_transaction():
+            context.run_migrations()
+
+
+if context.is_offline_mode():
+    run_migrations_offline()
+else:
+    run_migrations_online()

backend/migrations/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"}

backend/migrations/versions/938ae2fee021_posts_table.py

@@ -0,0 +1,43 @@
+"""posts table
+
+Revision ID: 938ae2fee021
+Revises: e42cf202d424
+Create Date: 2024-08-01 06:11:07.414657
+
+"""
+from alembic import op
+import sqlalchemy as sa
+
+
+# revision identifiers, used by Alembic.
+revision = '938ae2fee021'
+down_revision = 'e42cf202d424'
+branch_labels = None
+depends_on = None
+
+
+def upgrade():
+    # ### commands auto generated by Alembic - please adjust! ###
+    op.create_table('post',
+    sa.Column('id', sa.Integer(), nullable=False),
+    sa.Column('body', sa.String(length=140), nullable=False),
+    sa.Column('timestamp', sa.DateTime(), nullable=False),
+    sa.Column('user_id', sa.Integer(), nullable=False),
+    sa.ForeignKeyConstraint(['user_id'], ['user.id'], ),
+    sa.PrimaryKeyConstraint('id')
+    )
+    with op.batch_alter_table('post', schema=None) as batch_op:
+        batch_op.create_index(batch_op.f('ix_post_timestamp'), ['timestamp'], unique=False)
+        batch_op.create_index(batch_op.f('ix_post_user_id'), ['user_id'], unique=False)
+
+    # ### end Alembic commands ###
+
+
+def downgrade():
+    # ### commands auto generated by Alembic - please adjust! ###
+    with op.batch_alter_table('post', schema=None) as batch_op:
+        batch_op.drop_index(batch_op.f('ix_post_user_id'))
+        batch_op.drop_index(batch_op.f('ix_post_timestamp'))
+
+    op.drop_table('post')
+    # ### end Alembic commands ###

backend/migrations/versions/e42cf202d424_users_table.py

@@ -0,0 +1,42 @@
+"""users table
+
+Revision ID: e42cf202d424
+Revises: 
+Create Date: 2024-08-01 05:46:32.176166
+
+"""
+from alembic import op
+import sqlalchemy as sa
+
+
+# revision identifiers, used by Alembic.
+revision = 'e42cf202d424'
+down_revision = None
+branch_labels = None
+depends_on = None
+
+
+def upgrade():
+    # ### commands auto generated by Alembic - please adjust! ###
+    op.create_table('user',
+    sa.Column('id', sa.Integer(), nullable=False),
+    sa.Column('username', sa.String(length=64), nullable=False),
+    sa.Column('email', sa.String(length=120), nullable=False),
+    sa.Column('password_hash', sa.String(length=256), nullable=True),
+    sa.PrimaryKeyConstraint('id')
+    )
+    with op.batch_alter_table('user', schema=None) as batch_op:
+        batch_op.create_index(batch_op.f('ix_user_email'), ['email'], unique=True)
+        batch_op.create_index(batch_op.f('ix_user_username'), ['username'], unique=True)
+
+    # ### end Alembic commands ###
+
+
+def downgrade():
+    # ### commands auto generated by Alembic - please adjust! ###
+    with op.batch_alter_table('user', schema=None) as batch_op:
+        batch_op.drop_index(batch_op.f('ix_user_username'))
+        batch_op.drop_index(batch_op.f('ix_user_email'))
+
+    op.drop_table('user')
+    # ### end Alembic commands ###

backend/requirements.txt

@@ -1,10 +1,17 @@
+alembic==1.13.2
 blinker==1.8.2
 click==8.1.7
 Flask==3.0.3
+Flask-Migrate==4.0.7
+Flask-SQLAlchemy==3.1.1
 Flask-WTF==1.2.1
+greenlet==3.0.3
 itsdangerous==2.2.0
 Jinja2==3.1.4
+Mako==1.3.5
 MarkupSafe==2.1.5
 python-dotenv==1.0.1
+SQLAlchemy==2.0.31
+typing_extensions==4.12.2
 Werkzeug==3.0.3
 WTForms==3.1.2