refactor(docker): multi-stage app image build

fixes issue with version calculation from a dirty git index during
Docker build time / pip install time

there's no reason to have the .git directory in the app image, same with
all the extra files, tests, .devcontainer, etc.

copies the approach from eligibility-server

.dockerignore

@@ -1,7 +1,10 @@
-.github/
-.vscode/
 **/__pycache__/
-.flake8
-.*ignore
+node_modules/
+static/
+.coverage
 *.db
 *.egg-info
+*.log
+*.mo
+.DS_Store
+.env

.gitignore

@@ -2,6 +2,7 @@
 *.env
 *fixtures.json
 !benefits/core/migrations/local_fixtures.json
+*.log
 *.mo
 *.tfbackend
 *.tmp

appcontainer/Dockerfile

@@ -1,25 +1,37 @@
-FROM ghcr.io/cal-itp/docker-python-web:main
+FROM ghcr.io/cal-itp/docker-python-web:main AS build_wheel
+
+WORKDIR /build
 
 # upgrade pip
-RUN python -m pip install --upgrade pip
+RUN python -m pip install --upgrade pip && \
+    pip install build
+
+# copy source files
+COPY . .
+RUN git config --global --add safe.directory /build
+
+# build package
+RUN python -m build
+
+FROM ghcr.io/cal-itp/docker-python-web:main AS appcontainer
 
 # overwrite default nginx.conf
 COPY appcontainer/nginx.conf /etc/nginx/nginx.conf
 COPY appcontainer/proxy.conf /calitp/run/proxy.conf
 
-# copy files needed for version metadata
-COPY .git .git
-
-# copy source files
+# copy runtime files
+COPY --from=build_wheel /build/dist /build/dist
 COPY manage.py manage.py
 COPY bin bin
 COPY benefits benefits
-COPY pyproject.toml pyproject.toml
 
-RUN pip install -e .
+RUN echo "$(find /build/dist -name benefits*.whl)"
+# install source as a package
+RUN pip install $(find /build/dist -name benefits*.whl)
 
-# ensure $USER can compile messages in the locale directories
 USER root
+COPY LICENSE LICENSE
+#ensure $USER can compile messages in the locale directories
 RUN chmod -R 777 benefits/locale
 USER $USER
 

pyproject.toml

@@ -43,7 +43,7 @@ Documentation = "https://docs.calitp.org/benefits"
 Issues = "https://github.com/cal-itp/benefits/issues"
 
 [build-system]
-requires = ["setuptools>=65", "wheel", "setuptools-scm>=8"]
+requires = ["setuptools>=65", "setuptools-scm>=8"]
 build-backend = "setuptools.build_meta"
 
 [tool.black]
@@ -78,8 +78,9 @@ markers = [
     "request_path: use with session_request to initialize with the given path",
 ]
 
-[tool.setuptools]
-packages = ["benefits"]
+[tool.setuptools.packages.find]
+include = ["benefits*"]
+namespaces = false
 
 [tool.setuptools_scm]
 # intentionally left blank, but we need the section header to activate the tool