add "mini-tiangolo" to Dockerfile

- tiangolo/uvicorn-gunicorn is not available for ARM arch

Dockerfile

@@ -17,12 +17,31 @@ RUN yarn install --production false
 COPY ui ./
 RUN yarn build --dest /tmp/ovdashboard_ui/html
 
+######################
+# python preparation #
+######################
+
+ARG PYTHON_VERSION
+FROM python:${PYTHON_VERSION} as uvicorn-gunicorn
+
+# where credit is due ...
+LABEL maintainer="Sebastian Ramirez <tiangolo@gmail.com>"
+WORKDIR /usr/local/share/uvicorn-gunicorn
+
+# install uvicorn-gunicorn
+COPY "./install/mini-tiangolo/" "."
+
+RUN set -ex; \
+  chmod +x start.sh; \
+  python3 -m pip --no-cache-dir install gunicorn;
+
+CMD ["/usr/local/share/uvicorn-gunicorn/start.sh"]
+
 ###########
 # web app #
 ###########
 
-ARG PYTHON_VERSION
+FROM uvicorn-gunicorn AS production
-FROM tiangolo/uvicorn-gunicorn:python${PYTHON_VERSION} AS production
 
 # env setup
 WORKDIR /usr/local/src/ovdashboard_api
@@ -40,11 +59,8 @@ RUN set -ex; \
     libmagic1 \
   ; rm -rf /var/lib/apt/lists/*; \
   \
-  # remove example app
-  rm -rf /app; \
-  \
   # install ovdashboard_api
-  python -m pip --no-cache-dir install ./
+  python3 -m pip --no-cache-dir install ./
 
 # add prepared ovdashboard_ui
 COPY --from=build-ui /tmp/ovdashboard_ui /usr/local/share/ovdashboard_ui

install/mini-tiangolo/gunicorn_conf.py

@@ -0,0 +1,67 @@
+import json
+import multiprocessing
+import os
+
+workers_per_core_str = os.getenv("WORKERS_PER_CORE", "1")
+max_workers_str = os.getenv("MAX_WORKERS")
+use_max_workers = None
+if max_workers_str:
+    use_max_workers = int(max_workers_str)
+web_concurrency_str = os.getenv("WEB_CONCURRENCY", None)
+
+host = os.getenv("HOST", "0.0.0.0")
+port = os.getenv("PORT", "80")
+bind_env = os.getenv("BIND", None)
+use_loglevel = os.getenv("LOG_LEVEL", "info")
+if bind_env:
+    use_bind = bind_env
+else:
+    use_bind = f"{host}:{port}"
+
+cores = multiprocessing.cpu_count()
+workers_per_core = float(workers_per_core_str)
+default_web_concurrency = workers_per_core * cores
+if web_concurrency_str:
+    web_concurrency = int(web_concurrency_str)
+    assert web_concurrency > 0
+else:
+    web_concurrency = max(int(default_web_concurrency), 2)
+    if use_max_workers:
+        web_concurrency = min(web_concurrency, use_max_workers)
+accesslog_var = os.getenv("ACCESS_LOG", "-")
+use_accesslog = accesslog_var or None
+errorlog_var = os.getenv("ERROR_LOG", "-")
+use_errorlog = errorlog_var or None
+graceful_timeout_str = os.getenv("GRACEFUL_TIMEOUT", "120")
+timeout_str = os.getenv("TIMEOUT", "120")
+keepalive_str = os.getenv("KEEP_ALIVE", "5")
+
+# Gunicorn config variables
+loglevel = use_loglevel
+workers = web_concurrency
+bind = use_bind
+errorlog = use_errorlog
+worker_tmp_dir = "/dev/shm"
+accesslog = use_accesslog
+graceful_timeout = int(graceful_timeout_str)
+timeout = int(timeout_str)
+keepalive = int(keepalive_str)
+
+
+# For debugging and testing
+log_data = {
+    "loglevel": loglevel,
+    "workers": workers,
+    "bind": bind,
+    "graceful_timeout": graceful_timeout,
+    "timeout": timeout,
+    "keepalive": keepalive,
+    "errorlog": errorlog,
+    "accesslog": accesslog,
+    # Additional, non-gunicorn variables
+    "workers_per_core": workers_per_core,
+    "use_max_workers": use_max_workers,
+    "host": host,
+    "port": port,
+}
+print(json.dumps(log_data))

install/mini-tiangolo/start.sh

@@ -0,0 +1,20 @@
+#!/bin/sh
+set -e
+
+MODULE_NAME=${MODULE_NAME:-"app.main"}
+VARIABLE_NAME=${VARIABLE_NAME:-"app"}
+export APP_MODULE="${APP_MODULE:-"$MODULE_NAME:$VARIABLE_NAME"}"
+export GUNICORN_CONF="${GUNICORN_CONF:-"/usr/local/share/uvicorn-gunicorn/gunicorn_conf.py"}"
+export WORKER_CLASS="${WORKER_CLASS:-"uvicorn.workers.UvicornWorker"}"
+
+if [ -f "${PRE_START_PATH}" ] ; then
+    echo "Running script ${PRE_START_PATH}"
+    # shellcheck disable=SC1090
+    . "${PRE_START_PATH}"
+fi
+
+# Start Gunicorn
+exec gunicorn \
+    -k "${WORKER_CLASS}" \
+    -c "${GUNICORN_CONF}" \
+    "${APP_MODULE}"