Add check for a missing make extract_translations

Forgetting to run that causes weblate (or other translation tools) to
show outdated strings and not import new strings, which is bad for the
collaboration.

Fixes #118.

.github/workflows/main.yaml

@@ -50,6 +50,29 @@ jobs:
         run: |
           python -m flake8 snikket_web
 
+  translation-check:
+    runs-on: ubuntu-latest
+
+    name: 'lint: i18n'
+
+    steps:
+      - uses: actions/checkout@v2
+      - uses: actions/setup-python@v2
+        with:
+          python-version: '3.9'
+      - name: Install
+        run: |
+          set -euo pipefail
+          pip install flask-babel
+      - name: Linting
+        run: |
+          sed -ri '/^"POT-Creation-Date: /d' snikket_web/translations/messages.pot
+          git add snikket_web/translations/messages.pot
+          make extract_translations
+          sed -ri '/^"POT-Creation-Date: /d' snikket_web/translations/messages.pot
+          git diff --exit-code --color -- snikket_web/translations/messages.pot
+
+
   build:
     runs-on: ubuntu-latest
 

Dockerfile

@@ -17,8 +17,7 @@ COPY babel.cfg /opt/snikket-web-portal/babel.cfg
 
 WORKDIR /opt/snikket-web-portal
 
-RUN set -eu; \
-    pip3 install -r requirements.txt; \
+RUN pip3 install -r requirements.txt; \
     pip3 install -r build-requirements.txt; \
     make;
 
@@ -36,21 +35,20 @@ ENV SNIKKET_WEB_PROSODY_ENDPOINT=http://127.0.0.1:5280/
 
 HEALTHCHECK CMD nc -zv ${SNIKKET_TWEAK_PORTAL_INTERNAL_HTTP_INTERFACE:-127.0.0.1} ${SNIKKET_TWEAK_PORTAL_INTERNAL_HTTP_PORT:-5765}
 
-COPY requirements.txt /opt/snikket-web-portal/requirements.txt
-
-WORKDIR /opt/snikket-web-portal
-
 RUN set -eu; \
     export DEBIAN_FRONTEND=noninteractive ; \
     apt-get update ; \
     apt-get install -y --no-install-recommends \
-        python3 python3-pip python3-setuptools python3-wheel build-essential libpython3-dev; \
-    pip3 install -r requirements.txt; \
-    apt-get remove -y --autoremove build-essential libpython3-dev; \
+        python3 python3-pip python3-setuptools python3-wheel; \
     apt-get clean ; rm -rf /var/lib/apt/lists; \
     pip3 install hypercorn; \
     rm -rf /root/.cache;
 
+WORKDIR /opt/snikket-web-portal
+
+COPY requirements.txt /opt/snikket-web-portal/requirements.txt
+RUN pip3 install -r requirements.txt; rm -rf /root/.cache;
+
 COPY --from=build /opt/snikket-web-portal/snikket_web/ /opt/snikket-web-portal/snikket_web
 COPY babel.cfg /opt/snikket-web-portal/babel.cfg