Gunicorn is replaced with nginx-unit

We now serve Netbox with an nginx-unit instance instead of Gunicorn.
This allows us to get rid of the extra Nginx container because Unit is
also serving the static files. The static files are now collected at container
buildtime instead of every startup.

Dockerfile

@@ -12,27 +12,15 @@ RUN apk add --no-cache \
       libffi-dev \
       libxslt-dev \
       openldap-dev \
-      postgresql-dev
-
-WORKDIR /install
-
-RUN pip install --prefix="/install" --no-warn-script-location \
-# gunicorn is used for launching netbox
-      gunicorn \
-      greenlet \
-      eventlet \
-# napalm is used for gathering information from network devices
-      napalm \
-# ruamel is used in startup_scripts
-      'ruamel.yaml>=0.15,<0.16' \
-# django_auth_ldap is required for ldap
-      django_auth_ldap \
-# django-storages was introduced in 2.7 and is optional
-      django-storages
+      postgresql-dev \
+      py3-pip \
+      python3-dev \
+      && python3 -m venv /opt/netbox/venv \
+      && /opt/netbox/venv/bin/python3 -m pip install --upgrade pip setuptools
 
 ARG NETBOX_PATH
-COPY ${NETBOX_PATH}/requirements.txt /
-RUN pip install --prefix="/install" --no-warn-script-location -r /requirements.txt
+COPY ${NETBOX_PATH}/requirements.txt requirements-container.txt /
+RUN /opt/netbox/venv/bin/pip install -r /requirements.txt -r /requirements-container.txt
 
 ###
 # Main stage
@@ -44,6 +32,7 @@ FROM ${FROM} as main
 RUN apk add --no-cache \
       bash \
       ca-certificates \
+      curl \
       graphviz \
       libevent \
       libffi \
@@ -51,35 +40,38 @@ RUN apk add --no-cache \
       libressl \
       libxslt \
       postgresql-libs \
-      ttf-ubuntu-font-family
+      python3 \
+      py3-pip \
+      ttf-ubuntu-font-family \
+      unit \
+      unit-python3
 
 WORKDIR /opt
 
-COPY --from=builder /install /usr/local
+COPY --from=builder /opt/netbox/venv /opt/netbox/venv
 
 ARG NETBOX_PATH
 COPY ${NETBOX_PATH} /opt/netbox
 
 COPY docker/configuration.docker.py /opt/netbox/netbox/netbox/configuration.py
-COPY docker/gunicorn_config.py /etc/netbox/
-COPY docker/nginx.conf /etc/netbox-nginx/nginx.conf
 COPY docker/docker-entrypoint.sh /opt/netbox/docker-entrypoint.sh
+COPY docker/launch-netbox.sh /opt/netbox/launch-netbox.sh
 COPY startup_scripts/ /opt/netbox/startup_scripts/
 COPY initializers/ /opt/netbox/initializers/
 COPY configuration/ /etc/netbox/config/
+COPY docker/nginx-unit.json /etc/unit/
 
 WORKDIR /opt/netbox/netbox
 
-# Must set permissions for '/opt/netbox/netbox/static' directory
-# to g+w so that `./manage.py collectstatic` can be executed during
-# container startup.
 # Must set permissions for '/opt/netbox/netbox/media' directory
 # to g+w so that pictures can be uploaded to netbox.
-RUN mkdir static && chmod -R g+w static media
+RUN mkdir -p static /opt/unit/state/ /opt/unit/tmp/ \
+      && chmod -R g+w media /opt/unit/ \
+      && SECRET_KEY="dummy" /opt/netbox/venv/bin/python /opt/netbox/netbox/manage.py collectstatic --no-input
 
 ENTRYPOINT [ "/opt/netbox/docker-entrypoint.sh" ]
 
-CMD ["gunicorn", "-c /etc/netbox/gunicorn_config.py", "netbox.wsgi"]
+CMD [ "/opt/netbox/launch-netbox.sh" ]
 
 LABEL ORIGINAL_TAG="" \
       NETBOX_GIT_BRANCH="" \