Translate prestart and start scripts into Python

- This commit will refactor and translate the startup scripts from
  https://github.com/tiangolo/uvicorn-gunicorn-docker.
- prestart.py will replace prestart.sh
- start.py will replace start.sh and start-reload.sh

Author: br3ndonland

Dockerfile

@@ -4,9 +4,12 @@ COPY poetry.lock pyproject.toml inboard /app/
 WORKDIR /app/
 ENV APP_MODULE=inboard.base.main:app GUNICORN_CONF=/app/inboard/gunicorn_conf.py POETRY_VIRTUALENVS_CREATE=false
 RUN python -m pip install poetry && poetry install --no-dev --no-interaction -E fastapi
+CMD python /app/inboard/start.py
 
 FROM base as fastapi
-ENV APP_MODULE=inboard.fastapi.main:app POETRY_VIRTUALENVS_CREATE=false
+ENV APP_MODULE=inboard.fastapi.main:app
+CMD python /app/inboard/start.py
 
 FROM base as starlette
-ENV APP_MODULE=inboard.starlette.main:app POETRY_VIRTUALENVS_CREATE=false
+ENV APP_MODULE=inboard.starlette.main:app
+CMD python /app/inboard/start.py

inboard/prestart.py

@@ -0,0 +1,3 @@
+#!/usr/bin/env python3
+
+print("Running prestart.py. Add database migrations and other scripts here.")

inboard/start.py

@@ -0,0 +1,75 @@
+#!/usr/bin/env python3
+import os
+import subprocess
+from pathlib import Path, PurePath
+from typing import Tuple
+
+import uvicorn
+
+
+def set_app_module() -> str:
+    if Path("/app/app/main.py").is_file():
+        default_module_name = "app.main"
+    elif Path("/app/main.py").is_file():
+        default_module_name = "main"
+    module_name = os.getenv("MODULE_NAME", default_module_name)
+    variable_name = os.getenv("VARIABLE_NAME", "app")
+    app_module = os.getenv("APP_MODULE", f"{module_name}:{variable_name}")
+    os.environ["APP_MODULE"] = app_module
+    return app_module
+
+
+def set_gunicorn_conf() -> Tuple[str, str]:
+    if Path("/app/gunicorn_conf.py").is_file():
+        default_gunicorn_conf = "/app/gunicorn_conf.py"
+    elif Path("/app/app/gunicorn_conf.py").is_file():
+        default_gunicorn_conf = "/app/app/gunicorn_conf.py"
+    elif Path("/gunicorn_conf.py").is_file():
+        default_gunicorn_conf = "/gunicorn_conf.py"
+    gunicorn_conf = os.getenv("GUNICORN_CONF", default_gunicorn_conf)
+    os.environ["GUNICORN_CONF"] = gunicorn_conf
+    worker_class = os.getenv("WORKER_CLASS", "uvicorn.workers.UvicornWorker")
+    os.environ["WORKER_CLASS"] = worker_class
+    return gunicorn_conf, worker_class
+
+
+def run_pre_start_script(
+    pre_start_path: str = os.getenv("PRE_START_PATH", "/app/inboard/prestart.py")
+) -> None:
+    try:
+        print(f"Checking for pre-start script in {pre_start_path}.")
+        if Path(pre_start_path).is_file():
+            print(f"Running pre-start script script in {pre_start_path}.")
+            process = "python" if PurePath(pre_start_path).suffix == ".py" else "sh"
+            subprocess.run(process, pre_start_path)
+        else:
+            print("No pre-start script found.")
+    except Exception as e:
+        print(f"Error when running pre-start script: {e}")
+
+
+def start_server(
+    app_module: str = str(os.getenv("APP_MODULE", "/app/inboard.base.main:app")),
+    gunicorn_conf: str = str(
+        os.getenv("GUNICORN_CONF", "/app/inboard/gunicorn_conf.py")
+    ),
+    worker_class: str = str(os.getenv("WORKER_CLASS", "uvicorn.workers.UvicornWorker")),
+    with_reload: bool = bool(os.getenv("WITH_RELOAD", False)),
+) -> None:
+    if with_reload:
+        uvicorn.run(
+            app_module,
+            host=os.getenv("HOST", "0.0.0.0"),
+            port=int(os.getenv("PORT", "80")),
+            log_level=os.getenv("LOG_LEVEL", "info"),
+            reload=True,
+        )
+    else:
+        subprocess.run("gunicorn", "-k", worker_class, "-c", gunicorn_conf, app_module)
+
+
+if __name__ == "__main__":
+    set_app_module()
+    set_gunicorn_conf()
+    run_pre_start_script()
+    start_server()