Added an entrypoint to Dockerfile that ensures mermaid is part of the

container.

Dockerfile

@@ -12,7 +12,7 @@ RUN pip install mkdocs>=1.1.2 mkdocs-material>=7.1.0 mkdocs-mermaid2-plugin>=0.5
 # Linter #
 ##########
 
-RUN apt update && apt install -y nodejs npm aspell git
+RUN apt-get update && apt-get install -y nodejs npm aspell git
 
 RUN npm install -g markdownlint-cli markdown-link-check
 
@@ -29,6 +29,14 @@ RUN echo $'# gitlab.hrz.tu-chemnitz.de:22 SSH-2.0-OpenSSH_7.4\n\
 gitlab.hrz.tu-chemnitz.de ssh-rsa AAAAB3NzaC1yc2EAAAADAQABAAABAQDNixJ1syD506jOtiLPxGhAXsNnVfweFfzseh9/WrNxbTgIhi09fLb5aZI2CfOOWIi4fQz07S+qGugChBs4lJenLYAu4b0IAnEv/n/Xnf7wITf/Wlba2VSKiXdDqbSmNbOQtbdBLNu1NSt+inFgrreaUxnIqvWX4pBDEEGBAgG9e2cteXjT/dHp4+vPExKEjM6Nsxw516Cqv5H1ZU7XUTHFUYQr0DoulykDoXU1i3odJqZFZQzcJQv/RrEzya/2bwaatzKfbgoZLlb18T2LjkP74b71DeFIQWV2e6e3vsNwl1NsvlInEcsSZB1TZP+mKke7JWiI6HW2IrlSaGqM8n4h\n\
 gitlab.hrz.tu-chemnitz.de ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAIJ/cSNsKRPrfXCMjl+HsKrnrI3HgbCyKWiRa715S99BR\n' > ~/.ssh/known_hosts
 
+#Make sure that mermaid is integrated...
+RUN echo '#!/bin/bash' > /entrypoint.sh
+RUN echo 'test \! -e /docs/tud_theme/javascripts/mermaid.min.js && test -x /docs/util/download-newest-mermaid.js.sh && /docs/util/download-newest-mermaid.js.sh' >> /entrypoint.sh
+RUN echo 'exec "$@"' >> /entrypoint.sh
+RUN chmod u+x /entrypoint.sh
+
 WORKDIR /docs
 
 CMD ["mkdocs", "build", "--verbose", "--strict"]
+
+ENTRYPOINT ["/entrypoint.sh"]