add: wait for alembic to apply changes

docker/Dockerfile

@@ -8,14 +8,19 @@ RUN pip install wheel
 RUN pip install -r /app/geodata/requirements.txt
 RUN pip install gunicorn uvicorn
 
+RUN curl --location https://raw.githubusercontent.com/vishnubob/wait-for-it/81b1373f17855a4dc21156cfe1694c31d7d1792e/wait-for-it.sh > /usr/bin/wait-for-it \
+    && chmod +x  /usr/bin/wait-for-it
+
 EXPOSE 8000
 
 WORKDIR /app
 
 CMD [ \
-    "gunicorn", \
+    "/usr/bin/wait-for-it", "postgres:5432", "--timeout=45", "--strict", \
-    "--workers=2", \
+    "--", \
-    "--worker-class=uvicorn.workers.UvicornWorker", \
+    # might use exact migration hash here instead of upgrading to the latest "heads"
-    "--bind=0.0.0.0:8000", \
+    "alembic", "upgrade", "heads", \ 
+    "&&", \
+    "gunicorn", "--workers=2", "--worker-class=uvicorn.workers.UvicornWorker", "--bind=0.0.0.0:8000", \
     "geodata.main:app" \
 ]