feat: add Alembic migration setup and initial hero table creation

Author: umbertogriffo

README.md

@@ -70,7 +70,11 @@ Copy .𝐞𝐧𝐯.𝐞𝐱𝐚𝐦𝐩𝐥𝐞 → .𝐞𝐧𝐯 and fill it in
 ### Run the application
 
 ```shell
-python app/main.py
+cd src
+# Set up the database schema (Optional, if using database)
+migrate-db migrate
+# Run the application
+python main.py
 ```
 
 ## Docker
@@ -103,6 +107,33 @@ To stop it:
 docker compose down
 ```
 
+## Database Setup (Optional, if using database)
+
+The blueprint uses SQLModel (SQLAlchemy) with support for SQLite.
+
+### Perform migrations
+
+```bash
+# Set up the database schema
+cd src
+migrate-db
+# or directly with alembic
+uv run alembic --config alembic.ini upgrade head
+```
+
+The code migrate-db can be found in [migration_cli.py](src/migration_cli.py)
+
+### Generate migrations
+
+To generate new migration after adding fields to [SQLModel](src/models.py):
+
+```bash
+cd src
+uv run alembic --config alembic.ini revision --autogenerate -m "your text"
+```
+
+Has to be thoroughly tested, e.g adding a non-nullable column will not be flagged by Alembic!!
+
 ## Example of requests
 
 ```shell
@@ -137,3 +168,4 @@ curl -X POST \
 - [Using uv with FastAPI](https://docs.astral.sh/uv/guides/integration/fastapi/#using-uv-with-fastapi)
 - [Deployments Concepts](https://fastapi.tiangolo.com/deployment/concepts/)
 - [How to secure APIs built with FastAPI: A complete guide](https://escape.tech/blog/how-to-secure-fastapi-api/)
+- [Alembic](https://alembic.sqlalchemy.org/en/latest/front.html#installation)

pyproject.toml

@@ -9,17 +9,25 @@ dependencies = [
     "uvicorn==0.38.0",
     "pydantic-settings==2.12.0",
     "sqlmodel~=0.0.27",
+    "alembic>=1.17.2,<2.0.0",
 ]
 
 [dependency-groups]
 dev = [
     "pytest>=8.3.4",
     "ruff>=0.8.4",
-    "pre-commit~=4.2.0"
+    "pre-commit~=4.2.0",
+    "fire>=0.7.1",
 ]
 
 [tool.pytest.ini_options]
 pythonpath = [
     "src",
     "tests"
 ]
+
+[tool.uv]
+package = true
+
+[project.scripts]
+migrate-db = "migration_cli:main"

src/alembic.ini

@@ -0,0 +1,147 @@
+# A generic, single database configuration.
+
+[alembic]
+# path to migration scripts.
+# this is typically a path given in POSIX (e.g. forward slashes)
+# format, relative to the token %(here)s which refers to the location of this
+# ini file
+script_location = %(here)s/alembic
+
+# template used to generate migration file names; The default value is %%(rev)s_%%(slug)s
+# Uncomment the line below if you want the files to be prepended with date and time
+# see https://alembic.sqlalchemy.org/en/latest/tutorial.html#editing-the-ini-file
+# for all available tokens
+file_template = %%(year)d_%%(month).2d_%%(day).2d_%%(hour).2d%%(minute).2d-%%(rev)s_%%(slug)s
+
+# sys.path path, will be prepended to sys.path if present.
+# defaults to the current working directory.  for multiple paths, the path separator
+# is defined by "path_separator" below.
+prepend_sys_path = .
+
+
+# timezone to use when rendering the date within the migration file
+# as well as the filename.
+# If specified, requires the tzdata library which can be installed by adding
+# `alembic[tz]` to the pip requirements.
+# string value is passed to ZoneInfo()
+# 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 <script_location>/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 "path_separator"
+# below.
+# version_locations = %(here)s/bar:%(here)s/bat:%(here)s/alembic/versions
+
+# path_separator; This indicates what character is used to split lists of file
+# paths, including version_locations and prepend_sys_path within configparser
+# files such as alembic.ini.
+# The default rendered in new alembic.ini files is "os", which uses os.pathsep
+# to provide os-dependent path splitting.
+#
+# Note that in order to support legacy alembic.ini files, this default does NOT
+# take place if path_separator is not present in alembic.ini.  If this
+# option is omitted entirely, fallback logic is as follows:
+#
+# 1. Parsing of the version_locations option falls back to using the legacy
+#    "version_path_separator" key, which if absent then falls back to the legacy
+#    behavior of splitting on spaces and/or commas.
+# 2. Parsing of the prepend_sys_path option falls back to the legacy
+#    behavior of splitting on spaces, commas, or colons.
+#
+# Valid values for path_separator are:
+#
+# path_separator = :
+# path_separator = ;
+# path_separator = space
+# path_separator = newline
+#
+# Use os.pathsep. Default configuration used for new projects.
+path_separator = os
+
+# set to 'true' to search source files recursively
+# in each "version_locations" directory
+# new in Alembic version 1.10
+# recursive_version_locations = false
+
+# the output encoding used when revision files
+# are written from script.py.mako
+# output_encoding = utf-8
+
+# database URL.  This is consumed by the user-maintained env.py script only.
+# other means of configuring database URLs may be customized within the env.py
+# file.
+# sqlalchemy.url = sqlite:///database.db
+
+
+[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
+
+# lint with attempts to fix using "ruff" - use the module runner, against the "ruff" module
+# hooks = ruff
+# ruff.type = module
+# ruff.module = ruff
+# ruff.options = check --fix REVISION_SCRIPT_FILENAME
+
+# Alternatively, use the exec runner to execute a binary found on your PATH
+# hooks = ruff
+# ruff.type = exec
+# ruff.executable = ruff
+# ruff.options = check --fix REVISION_SCRIPT_FILENAME
+
+# Logging configuration.  This is also consumed by the user-maintained
+# env.py script only.
+[loggers]
+keys = root,sqlalchemy,alembic
+
+[handlers]
+keys = console
+
+[formatters]
+keys = generic
+
+[logger_root]
+level = WARNING
+handlers = console
+qualname =
+
+[logger_sqlalchemy]
+level = WARNING
+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

src/alembic/README

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

src/alembic/env.py

@@ -0,0 +1,90 @@
+from logging.config import fileConfig
+
+from alembic import context
+from config import settings
+from models import SQLModel  # noqa
+from sqlalchemy import engine_from_config, pool
+from utils.log import get_logger
+
+logger = get_logger()
+
+# 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.
+if config.config_file_name is not None:
+    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() -> None:
+    """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")
+    logger.info(f"DATABASE_URL {url}")
+    context.configure(
+        url=url,
+        target_metadata=target_metadata,
+        literal_binds=True,
+        dialect_opts={"paramstyle": "named"},
+    )
+
+    with context.begin_transaction():
+        context.run_migrations()
+
+
+def run_migrations_online() -> None:
+    """Run migrations in 'online' mode.
+
+    In this scenario we need to create an Engine
+    and associate a connection with the context.
+
+    """
+    # Get database URL from environment variable
+    if settings.DATABASE_URL is None:
+        logger.info(
+            "DATABASE_URL environment variable is not set. "
+            "Applying migrations Using sqlalchemy.url from alembic.ini."
+        )
+    else:
+        logger.info("Applying migrations Using DATABASE_URL from environment variable.")
+        config.set_main_option("sqlalchemy.url", settings.DATABASE_URL)
+
+    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()

src/alembic/script.py.mako

@@ -0,0 +1,28 @@
+"""${message}
+
+Revision ID: ${up_revision}
+Revises: ${down_revision | comma,n}
+Create Date: ${create_date}
+
+"""
+from typing import Sequence, Union
+
+from alembic import op
+import sqlalchemy as sa
+${imports if imports else ""}
+
+# revision identifiers, used by Alembic.
+revision: str = ${repr(up_revision)}
+down_revision: Union[str, Sequence[str], None] = ${repr(down_revision)}
+branch_labels: Union[str, Sequence[str], None] = ${repr(branch_labels)}
+depends_on: Union[str, Sequence[str], None] = ${repr(depends_on)}
+
+
+def upgrade() -> None:
+    """Upgrade schema."""
+    ${upgrades if upgrades else "pass"}
+
+
+def downgrade() -> None:
+    """Downgrade schema."""
+    ${downgrades if downgrades else "pass"}

src/alembic/versions/2025_12_16_1334-b1b12308dd01_init.py

@@ -0,0 +1,40 @@
+"""init
+
+Revision ID: b1b12308dd01
+Revises:
+Create Date: 2025-12-16 13:34:13.358560
+
+"""
+
+from typing import Sequence, Union
+
+import sqlalchemy as sa
+import sqlmodel.sql.sqltypes
+from alembic import op
+
+# revision identifiers, used by Alembic.
+revision: str = "b1b12308dd01"
+down_revision: Union[str, Sequence[str], None] = None
+branch_labels: Union[str, Sequence[str], None] = None
+depends_on: Union[str, Sequence[str], None] = None
+
+
+def upgrade() -> None:
+    """Upgrade schema."""
+    # ### commands auto generated by Alembic - please adjust! ###
+    op.create_table(
+        "hero",
+        sa.Column("name", sqlmodel.sql.sqltypes.AutoString(), nullable=False),
+        sa.Column("age", sa.Integer(), nullable=True),
+        sa.Column("id", sa.Integer(), nullable=False),
+        sa.Column("secret_name", sqlmodel.sql.sqltypes.AutoString(), nullable=False),
+        sa.PrimaryKeyConstraint("id"),
+    )
+    # ### end Alembic commands ###
+
+
+def downgrade() -> None:
+    """Downgrade schema."""
+    # ### commands auto generated by Alembic - please adjust! ###
+    op.drop_table("hero")
+    # ### end Alembic commands ###