Next.js: Telemetry needs to be disabled without voodoo

[Paratron]

Bug report

We do not want to have telemetry enabled when performing a next build inside a docker container in our build pipeline. It seems like the npx command described in the documentation does not work here. Also its very opaque _what_ that command actually does and where the information that no telemetry is desired is actually stored.

It should be possible to disable telemetry by passing a flag to npm run build instead of executing a npx command beforehand.

Describe the bug

Inside our dockerfile, we try to disable telemetry, then performing the build:

...
# We do not want to be tracked
RUN npx next telemetry disable

# Building app
RUN npm run build
...

According to our pipeline logs, telemetry seems to be re-enabled when the actual build is performed:

Step 13/25 : RUN npx next telemetry disable
 ---> Running in 3cee707075fa
Attention: Next.js now collects completely anonymous telemetry regarding usage.
This information is used to shape Next.js' roadmap and prioritize features.
You can learn more, including how to opt-out if you'd not like to participate in this anonymous program, by visiting the following URL:
https://nextjs.org/telemetry

Your preference has been saved.

Status: Disabled

You have opted-out of Next.js' anonymous telemetry program.
No data will be collected from your machine.
Learn more: https://nextjs.org/telemetry

Removing intermediate container 3cee707075fa
 ---> f765f98e92b1
Step 14/25 : RUN npm run build
 ---> Running in 0c0c4f9963b2

> [email protected] build /app
> cross-env NODE_ICU_DATA=node_modules/full-icu next build

Creating an optimized production build...
Attention: Next.js now collects completely anonymous telemetry regarding usage.
This information is used to shape Next.js' roadmap and prioritize features.
You can learn more, including how to opt-out if you'd not like to participate in this anonymous program, by visiting the following URL:
https://nextjs.org/telemetry

To Reproduce

Try disabling telemetry and then build inside a docker container.

Expected behavior

I expected telemetry to be disabled.

System information

• Docker with node:12-alpine
• Gitlab CI
• nextJS 6.13.4

[Paratron]

Also related to this issue is my comment from another issue:

https://github.com/zeit/next.js/issues/8851#issuecomment-591710955

[Janpot]

According to the doc:

You may also opt-out by setting an environment variable: NEXT_TELEMETRY_DISABLED=1.

Personally I'd prefer there to be a property in next.config.js.

[timneutkens]

You can add the environment variable NEXT_TELEMETRY_DISABLED=1 as per the documentation.

The command writes a file into the home directory, I guess in docker that's not preserved in between steps 🤔

[rafaelalmeidatk]

Try to add the env var in your Dockerfile: ENV NEXT_TELEMETRY_DISABLED 1

[Timer]

Closing this as the npx next telemetry disable command is to disable collection system-wide, meaning for all Next.js projects a user works on.
Viewing your docker logs, you are throwing away the intermediate container which is why the setting is being lost.

---

To disable this in your Dockerfile, you can add the following line for each of your build stages:

ENV NEXT_TELEMETRY_DISABLED 1