add sqlmodel and alembic

docker-compose.yml

@@ -10,7 +10,7 @@ services:
     ports:
       - 8004:8000
     environment:
-      - DATABASE_URL=postgresql://postgres:postgres@db:5432/foo
+      - DATABASE_URL=postgresql+asyncpg://postgres:postgres@db:5432/foo
     depends_on:
       - db
 

project/alembic.ini

@@ -0,0 +1,100 @@
+# A generic, single database configuration.
+
+[alembic]
+# path to migration scripts
+script_location = migrations
+
+# template used to generate migration files
+# file_template = %%(rev)s_%%(slug)s
+
+# sys.path path, will be prepended to sys.path if present.
+# defaults to the current working directory.
+prepend_sys_path = .
+
+# timezone to use when rendering the date within the migration file
+# as well as the filename.
+# If specified, requires the python-dateutil library that can be
+# installed by adding `alembic[tz]` to the pip requirements
+# 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 migrations/versions.  When using multiple version
+# directories, initial revisions must be specified with --version-path.
+# The path separator used here should be the separator specified by "version_path_separator"
+# version_locations = %(here)s/bar:%(here)s/bat:migrations/versions
+
+# version path separator; As mentioned above, this is the character used to split
+# version_locations. Valid values are:
+#
+# version_path_separator = :
+# version_path_separator = ;
+# version_path_separator = space
+version_path_separator = os  # default: use os.pathsep
+
+# the output encoding used when revision files
+# are written from script.py.mako
+# output_encoding = utf-8
+
+sqlalchemy.url = postgresql+asyncpg://postgres:postgres@db:5432/foo
+
+
+[post_write_hooks]
+# post_write_hooks defines scripts or Python functions that are run
+# on newly generated revision scripts.  See the documentation for further
+# detail and examples
+
+# format using "black" - use the console_scripts runner, against the "black" entrypoint
+# hooks = black
+# black.type = console_scripts
+# black.entrypoint = black
+# black.options = -l 79 REVISION_SCRIPT_FILENAME
+
+# 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

project/app/db.py

@@ -0,0 +1,25 @@
+import os
+
+from sqlmodel import SQLModel
+
+from sqlalchemy.ext.asyncio import AsyncSession, create_async_engine
+from sqlalchemy.orm import sessionmaker
+
+
+DATABASE_URL = os.environ.get("DATABASE_URL")
+
+engine = create_async_engine(DATABASE_URL, echo=True, future=True)
+
+
+async def init_db():
+    async with engine.begin() as conn:
+        # await conn.run_sync(SQLModel.metadata.drop_all)
+        await conn.run_sync(SQLModel.metadata.create_all)
+
+
+async def get_session() -> AsyncSession:
+    async_session = sessionmaker(
+        engine, class_=AsyncSession, expire_on_commit=False
+    )
+    async with async_session() as session:
+        yield session

project/app/main.py

@@ -1,4 +1,9 @@
-from fastapi import FastAPI
+from fastapi import Depends, FastAPI
+from sqlalchemy.future import select
+from sqlalchemy.ext.asyncio import AsyncSession
+
+from app.db import get_session, init_db
+from app.models import Song, SongCreate
 
 app = FastAPI()
 
@@ -6,3 +11,19 @@ app = FastAPI()
 @app.get("/ping")
 async def pong():
     return {"ping": "pong!"}
+
+
+@app.get("/songs", response_model=list[Song])
+async def get_songs(session: AsyncSession = Depends(get_session)):
+    result = await session.execute(select(Song))
+    songs = result.scalars().all()
+    return [Song(name=song.name, artist=song.artist, year=song.year, id=song.id) for song in songs]
+
+
+@app.post("/songs")
+async def add_song(song: SongCreate, session: AsyncSession = Depends(get_session)):
+    song = Song(name=song.name, artist=song.artist, year=song.year)
+    session.add(song)
+    await session.commit()
+    await session.refresh(song)
+    return song

project/app/models.py

@@ -0,0 +1,17 @@
+from typing import Optional
+
+from sqlmodel import SQLModel, Field
+
+
+class SongBase(SQLModel):
+    name: str
+    artist: str
+    year: Optional[int] = None
+
+
+class Song(SongBase, table=True):
+    id: int = Field(default=None, primary_key=True)
+
+
+class SongCreate(SongBase):
+    pass

project/migrations/README

@@ -0,0 +1 @@
+Generic single-database configuration with an async dbapi.

project/migrations/env.py

@@ -0,0 +1,87 @@
+import asyncio
+from logging.config import fileConfig
+
+from sqlalchemy import engine_from_config
+from sqlalchemy import pool
+from sqlalchemy.ext.asyncio import AsyncEngine
+from sqlmodel import SQLModel
+
+from alembic import context
+
+from app.models import Song
+
+# 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
+target_metadata = SQLModel.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.
+
+
+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,
+        dialect_opts={"paramstyle": "named"},
+    )
+
+    with context.begin_transaction():
+        context.run_migrations()
+
+
+def do_run_migrations(connection):
+    context.configure(connection=connection, target_metadata=target_metadata)
+
+    with context.begin_transaction():
+        context.run_migrations()
+
+
+async 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 = AsyncEngine(
+        engine_from_config(
+            config.get_section(config.config_ini_section),
+            prefix="sqlalchemy.",
+            poolclass=pool.NullPool,
+            future=True,
+        )
+    )
+
+    async with connectable.connect() as connection:
+        await connection.run_sync(do_run_migrations)
+
+
+if context.is_offline_mode():
+    run_migrations_offline()
+else:
+    asyncio.run(run_migrations_online())

project/migrations/script.py.mako

@@ -0,0 +1,25 @@
+"""${message}
+
+Revision ID: ${up_revision}
+Revises: ${down_revision | comma,n}
+Create Date: ${create_date}
+
+"""
+from alembic import op
+import sqlalchemy as sa
+import sqlmodel
+${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"}

project/migrations/versions/53754b2c08a4_add_year.py

@@ -0,0 +1,31 @@
+"""add year
+
+Revision ID: 53754b2c08a4
+Revises: f9c634db477d
+Create Date: 2021-09-10 00:52:38.668620
+
+"""
+from alembic import op
+import sqlalchemy as sa
+import sqlmodel
+
+
+# revision identifiers, used by Alembic.
+revision = '53754b2c08a4'
+down_revision = 'f9c634db477d'
+branch_labels = None
+depends_on = None
+
+
+def upgrade():
+    # ### commands auto generated by Alembic - please adjust! ###
+    op.add_column('song', sa.Column('year', sa.Integer(), nullable=True))
+    op.create_index(op.f('ix_song_year'), 'song', ['year'], unique=False)
+    # ### end Alembic commands ###
+
+
+def downgrade():
+    # ### commands auto generated by Alembic - please adjust! ###
+    op.drop_index(op.f('ix_song_year'), table_name='song')
+    op.drop_column('song', 'year')
+    # ### end Alembic commands ###

project/migrations/versions/f9c634db477d_init.py

@@ -0,0 +1,40 @@
+"""init
+
+Revision ID: f9c634db477d
+Revises: 
+Create Date: 2021-09-10 00:24:32.718895
+
+"""
+from alembic import op
+import sqlalchemy as sa
+import sqlmodel
+
+
+# revision identifiers, used by Alembic.
+revision = 'f9c634db477d'
+down_revision = None
+branch_labels = None
+depends_on = None
+
+
+def upgrade():
+    # ### commands auto generated by Alembic - please adjust! ###
+    op.create_table('song',
+    sa.Column('name', sqlmodel.sql.sqltypes.AutoString(), nullable=False),
+    sa.Column('artist', sqlmodel.sql.sqltypes.AutoString(), nullable=False),
+    sa.Column('id', sa.Integer(), nullable=True),
+    sa.PrimaryKeyConstraint('id')
+    )
+    op.create_index(op.f('ix_song_artist'), 'song', ['artist'], unique=False)
+    op.create_index(op.f('ix_song_id'), 'song', ['id'], unique=False)
+    op.create_index(op.f('ix_song_name'), 'song', ['name'], unique=False)
+    # ### end Alembic commands ###
+
+
+def downgrade():
+    # ### commands auto generated by Alembic - please adjust! ###
+    op.drop_index(op.f('ix_song_name'), table_name='song')
+    op.drop_index(op.f('ix_song_id'), table_name='song')
+    op.drop_index(op.f('ix_song_artist'), table_name='song')
+    op.drop_table('song')
+    # ### end Alembic commands ###

project/requirements.txt

@@ -1,2 +1,5 @@
+alembic==1.7.1
+asyncpg==0.24.0
 fastapi==0.68.1
+sqlmodel==0.0.4
 uvicorn==0.15.0