trying new Dockerfile

Dockerfile

@@ -1,5 +1,6 @@
 FROM python:3.8-alpine
 
+# install required packages
 RUN apk add --no-cache gcc
 RUN apk add --no-cache python3-dev
 RUN apk add --no-cache libc-dev
@@ -7,7 +8,10 @@ RUN apk add --no-cache libffi-dev
 RUN apk add --no-cache openssl
 RUN apk add --no-cache openssl-dev
 
+# add user that will be used to install and run the application
 RUN adduser -D deploy
+
+# switch to the created user and install the application
 USER deploy
 ENV PATH "$PATH:/home/deploy/.local/bin"
 
@@ -21,4 +25,12 @@ RUN pip install wheel
 RUN pip install -r requirements.txt
 RUN flit install --pth-file
 
+# switch back to root to remove header files
+USER root
+RUN apk delete python3-dev
+RUN apk delete libffi-dev
+RUN apk delete openssl-dev
+
+# switch to the created user to run the application
+USER deploy
 CMD ["gunicorn", "--paster", "/app/production.ini", "-b", "0.0.0.0:8000"]

flit_freeze.py

@@ -0,0 +1,51 @@
+import re
+import subprocess
+import sys
+import toml
+
+
+REGEX_PKG = re.compile("^([\w\.\[\],_-]+)")
+REGEX_SINGLE = re.compile("([\w\._-]+)")
+
+
+def get_pip_freeze_list():
+    freeze_text = subprocess.check_output(
+        [sys.executable, '-m', 'pip', 'list', '-l', '--format=freeze']
+    )
+    freeze_text = freeze_text.decode("utf-8")
+    return freeze_text.strip().splitlines()
+
+def get_raw_packages_from_pyproject_file(filename="pyproject.toml"):
+    pyproject = toml.load(filename)
+    _flit = pyproject["tool"]["flit"]["metadata"]
+    pyproject_pkgs = _flit["requires"]
+    pyproject_pkgs += _flit["requires-extra"]["test"]
+    pyproject_pkgs += _flit["requires-extra"]["dev"]
+    return pyproject_pkgs
+
+
+def _parse_package_names(toml_pkgs):
+    for pkg in toml_pkgs:
+        group = REGEX_PKG.match(pkg)[0]
+        yield from REGEX_SINGLE.finditer(group)
+
+def get_package_names(filename="pyproject.toml"):
+    toml_pkgs = get_raw_packages_from_pyproject_file(filename)
+    as_string = (m.group() for m in _parse_package_names(toml_pkgs))
+    lowercased = (item.lower() for item in as_string)
+    return {item.replace("_", "-") for item in lowercased}
+
+def filter_toml_pkgs_from_freeze_list(freeze_list, toml_pkgs):
+    for line in freeze_list:
+        freeze_pkg, _ = line.split("=", 1)
+        if freeze_pkg.lower() in toml_pkgs:
+            yield line
+
+def main(toml_file="pyproject.toml"):
+    freeze_list = get_pip_freeze_list()
+    toml_pkgs = get_package_names(toml_file)
+    return filter_toml_pkgs_from_freeze_list(freeze_list, toml_pkgs)
+
+
+if __name__ == "__main__":
+    print("\n".join(sorted(main(), key=lambda x: x.lower())))