Release 0.2.0 — Security, Performance & Architecture Improvements

AGENTS.md

@@ -6,7 +6,7 @@ Guide for AI coding agents working on the Commerce System Demo project.
 
 Commerce System Demo is a FastAPI-based commerce service that provides RESTful APIs for managing products, categories, and implementing search functionality. The project includes built-in observability with OpenTelemetry metrics, logging, and distributed tracing.
 
-**Current Version**: 0.1.5 (following [Semantic Versioning](https://semver.org/))
+**Current Version**: 0.2.0 (following [Semantic Versioning](https://semver.org/))
 
 ## Setup Commands
 
@@ -109,7 +109,7 @@ app/
 
 ### Docker
 
-- **Build image**: `docker build -t commerce-system-demo:0.1.5 .`
+- **Build image**: `docker build -t commerce-system-demo:0.2.0 .`
 - **View Dockerfile**: Includes Python dependencies, migration scripts, and app code
 - **Build context**: Includes `scripts/`, `app/`, and `observability/` directories
 
@@ -192,7 +192,7 @@ This project follows [Semantic Versioning 2.0.0](https://semver.org/):
 - **MINOR**: Backward-compatible new features
 - **PATCH**: Backward-compatible bug fixes
 
-Current version is **0.1.5** (initial development). Version is defined in:
+Current version is **0.2.0** (initial development). Version is defined in:
 - `pyproject.toml` (project metadata)
 - `app/main.py` (FastAPI version)
 - `app/observability/metrics.py` (meter version)

CHANGELOG.md

@@ -11,10 +11,44 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 - Enhanced search with full-text indexing support
 - Bulk import/export endpoints for products and categories
-- Rate limiting and request throttling
 - Advanced filtering options for product search
 - Product images storage optimization
 
+## [0.2.0] - 2026-03-22
+
+### Added
+
+- Rate limiting with slowapi — IP-based throttling on search endpoint with configurable default and per-route limits
+- `rate_limit_default` and `rate_limit_search` settings in `app/core/config.py`
+- Alembic migration framework with async PostgreSQL support (`alembic/` directory, `alembic.ini`)
+- Initial Alembic migration (`001_initial_schema.py`) matching the existing `create_all` schema
+- `timed_execute_all`, `timed_execute_one` helpers in `app/observability/db_timing.py` for instrumented query execution
+- `_escape_like()` utility in `app/services/product_service.py` for sanitizing LIKE metacharacters
+- `field_serializer` on `ProductUpdate.image_url` to serialize `AnyHttpUrl` to plain `str`
+- Integration tests for category depth limits, cycle detection, self-reference rejection, and LIKE injection
+- Documentation in README clarifying `.env` setup steps with a table of key variables and defaults
+
+### Changed
+
+- Search query uses `COUNT(*) OVER()` window function instead of a separate count query, eliminating a second database roundtrip
+- Category depth validation (`validate_category_parent`) consolidated from N+1 sequential queries to a single recursive CTE
+- Category reparent validation (`validate_category_reparent`) consolidated from 4 sequential queries to a single combined CTE query
+- `get_session` dependency now reads from `request.app.state.session_factory` (proper DI via app state) instead of module-level globals
+- Application lifespan stores `engine` and `session_factory` on `app.state`
+- Health endpoint reads engine from `request.app.state.engine` instead of importing `get_engine()`
+- `create_schema()` / `drop_schema()` accept an optional `engine` parameter
+- Test fixtures set `app.state.engine` and `app.state.session_factory` explicitly (httpx ASGITransport skips ASGI lifespan)
+
+### Fixed
+
+- LIKE metacharacters (`%`, `_`, `\`) in search queries are now escaped, preventing wildcard injection
+- `ProductUpdate.image_url` now serializes correctly from `AnyHttpUrl` to `str` for database persistence
+
+### Security
+
+- Added IP-based rate limiting to protect against request flooding
+- Escaped LIKE wildcards in user-supplied search input to prevent pattern injection
+
 ## [0.1.5] - 2026-03-22
 
 ### Fixed

README.md

@@ -496,12 +496,23 @@ python3 -m venv .venv
 pip install -e '.[dev]'
 ```
 
-3. Copy environment config and adjust DB credentials if needed:
+3. Copy environment config and adjust as needed:
 
 ```bash
 cp .env.example .env
 ```
 
+The `.env` file is **not** committed to the repository (it is listed in `.gitignore`). The provided `.env.example` contains sensible defaults for local development. Key variables you may want to review:
+
+| Variable | Default | Purpose |
+|---|---|---|
+| `DATABASE_URL` | `postgresql+asyncpg://postgres:postgres@localhost:5432/commerce_demo` | PostgreSQL connection string. Change host/port/credentials to match your local setup, or leave as-is when using Docker Compose (it provisions the DB automatically). |
+| `TELEMETRY_ENABLED` | `true` | Set to `false` if you are not running the observability stack. |
+| `API_PREFIX` | `/api/v1` | URL prefix for all API routes. |
+| `AUTO_CREATE_SCHEMA` | `true` | Creates tables on startup when no Alembic migration has been run yet. |
+
+> **Tip:** When using **Docker Compose** (Option A below), the compose file passes its own `DATABASE_URL` pointing at the containerized PostgreSQL, so the value in `.env` is only used if you run the dev server directly on the host (Option C).
+
 ### 8.2. Development Server
 
 #### Option A: Run full stack with Docker Compose (recommended)

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
+# Or organize into date-based subdirectories (requires recursive_version_locations = true)
+# file_template = %%(year)d/%%(month).2d/%%(day).2d_%%(hour).2d%%(minute).2d_%%(second).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.  Overridden at runtime by env.py from DATABASE_URL env var.
+sqlalchemy.url =
+
+
+[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

alembic/README

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

alembic/env.py

@@ -0,0 +1,73 @@
+"""Alembic environment configuration for async migrations."""
+
+import asyncio
+from logging.config import fileConfig
+
+from sqlalchemy import pool
+from sqlalchemy.engine import Connection
+from sqlalchemy.ext.asyncio import async_engine_from_config
+
+from alembic import context
+
+# Import all models so that Base.metadata is fully populated.
+import app.models  # noqa: F401
+from app.core.config import get_settings
+from app.db.base import Base
+
+config = context.config
+
+# Interpret the config file for Python logging.
+if config.config_file_name is not None:
+    fileConfig(config.config_file_name)
+
+# Point autogenerate at the project's declarative metadata.
+target_metadata = Base.metadata
+
+# Override sqlalchemy.url from the application settings (DATABASE_URL env var).
+config.set_main_option("sqlalchemy.url", get_settings().database_url)
+
+
+def run_migrations_offline() -> None:
+    """Run migrations in 'offline' mode (emit SQL to stdout)."""
+    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: Connection) -> None:
+    context.configure(connection=connection, target_metadata=target_metadata)
+
+    with context.begin_transaction():
+        context.run_migrations()
+
+
+async def run_async_migrations() -> None:
+    """Create an async engine and run migrations."""
+    connectable = async_engine_from_config(
+        config.get_section(config.config_ini_section, {}),
+        prefix="sqlalchemy.",
+        poolclass=pool.NullPool,
+    )
+
+    async with connectable.connect() as connection:
+        await connection.run_sync(do_run_migrations)
+
+    await connectable.dispose()
+
+
+def run_migrations_online() -> None:
+    """Run migrations in 'online' mode."""
+    asyncio.run(run_async_migrations())
+
+
+if context.is_offline_mode():
+    run_migrations_offline()
+else:
+    run_migrations_online()

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"}