How to find out the content of an image?

Question

Node.js

I have dockerized an angular application with the following file:

FROM node:alpine AS builder

WORKDIR /app

COPY . .

RUN npm install && \
    npm run build

FROM nginx:alpine

COPY --from=builder /app/dist/* /usr/share/nginx/html/

As a result, after starting the container with the command:
$ docker run -p 80:80 my-angular-app:v1
I have the opportunity to work with the running application through my browser using the localhost:80 address.
It turns out that the build was assembled in the container and this build was placed in the desired directory of the nginx server.
But I don’t understand where it came from in the nginx image. I downloaded the image only for nodejs. On the documentation page, I did not find any mention of nginx. Please tell me where did it come from?

Answer 1

FROM nginx:alpine

Does this line bother you at all?