How do you expose port 3000 using an Azure Web App Container?

Question

I'm running a react boilerplate app within a docker container, hosted Azure Web App Containers.

Locally, I spin the app up with:

docker run -p 3000:3000 431e522f8a87

My docker file looks like this:

FROM node:8.9.3
EXPOSE 3000
RUN mkdir -p src
WORKDIR /src
ADD . /src
RUN yarn install
RUN yarn build 
CMD ["yarn", "run", "start:prod"]

APPLICATION SETTINGS

I've tried editing the Application Settings, to no avail, with the key/value pair: WEBSITES_PORT=3000

Apparently Azure only exposes ports 80 and 443 for inbound traffic:

80: Default port for inbound HTTP traffic to apps running in App Service Plans in an App Service Environment. On an ILB-enabled ASE, this port is bound to the ILB address of the ASE.

443: Default port for inbound SSL traffic to apps running in App Service Plans in an App Service Environment. On an ILB-enabled ASE, this port is bound to the ILB address of the ASE.

How do I expose port 3000 in an Azure App Service?

Solution

User 4c74356b41 is correct.

In APPLICATION SETTINGS you need to set the key / value pair WEBSITES_PORT.

For some reason it's not working on this image, but I went through another example and did it all through the command line, and it worked fine.

Comments

[4c74356b41]

website_port is indeed the proper setting for this. docs.microsoft.com/en-us/azure/app-service/containers/…

[Dave Voyles]

You may be right. The docs say you can, but some reason I'm not able to. Hmmm... "My custom container listens to a port other than port 80. How can I configure my app to route requests to that port? We have automatic port detection. You can also specify an app setting called WEBSITES_PORT and give it the value of the expected port number. Previously, the platform used the PORT app setting. We are planning to deprecate this app setting and to use WEBSITES_PORT exclusively."

[Dave Voyles]

@RıfatErdemSahin I am not sure. I never understood why it did not work in this instance unfortunately.

[Rıfat Erdem Sahin]

also created another thread related to this one.I am unable to run the containers in Azure. devops.stackexchange.com/questions/4543/…

[Rıfat Erdem Sahin]

WEBSITES_PORT worked in my case. The external port is still 80.

[Phil]

after setting websites_port how do you trigger it to restart, just restart web app?

[TorstenS]

Where would I find those APPLICATION SETTINGS?

[Dave Voyles]

@TorstenS in the Azure Portal, you can find it here: docs.microsoft.com/en-us/azure/app-service/web-sites-configu‌​re