Docker: Listen on port 80

Hi there,

I'm using the stock NodeRed docker image and I need it to listen to port 80.
The container is running on Azure container instance. On my localhost I could simply run docker run -d -p 80:8080 nodered to map the internal port to 80.
Though this option is not provided by the azure equivalent command.
If I set the port 80 in the settings.js, I get the following error:

[error] Error: listen EACCES: permission denied 0.0.0.0:80
    at Server.setupListenHandle [as _listen2] (net.js:1262:19)
    at listenInCluster (net.js:1327:12)
    at doListen (net.js:1460:7)
    at process._tickCallback (internal/process/next_tick.js:63:19)

I think I get this error since nodered has no access to listen to port 80. Is there a good way to get this to work.
Thanks in advance for your answer.
Cheers
Timo

Just if someone might end up here while using a search engine:

I ended up using an Azure App Service with the official Docker Image from Docker Hub (nodered/node-red) and used a FileShare pointing to /data inside the container.

But to accomplish the task I asked here originally I used the following Dockerfile

FROM nodered/node-red
USER root
RUN apk add iptables --no-cache
USER root
COPY ./sites-enabled /etc/nginx/sites-enabled/
RUN apk add nginx --no-cache
EXPOSE 80/tcp
COPY ./data /data

with ./sites-enabled/node:

server {
listen 80;
server_name example.com;
    location /ui {
    proxy_set_header X-Forwarded-For $remote_addr;
    proxy_set_header Host $http_host;
    proxy_pass "http://127.0.0.1:1880";
    }
}

and a directory ./data containing all the npm modules, flows and configuration.