Docker在生产中撰写

Question

Trying to use docker-compose to build and up a simple Node.js application. Although I ran into the same problem with a Django application so I think I'm just missing some sort of vital step. Here is my Dockerfile:

FROM node:4.2.1
CMD mkdir -p /var/app
COPY . /var/app
EXPOSE 3000
CMD node /var/app/index.js

When I run docker compose up pointed towards a digital ocean machine it throws a node error suggesting it can't find the code in /var/app. Is there some other mechanism I am supposed to use to get my code onto the machine other than docker?

Answer 1

The line CMD mkdir -p /var/app is wrong. It should be only one CMD in a Dockerfile, usually at the end.

Only the last CMD directive in a chain of inherited docker images will be executed.

You should use RUN instead

From Dockerfile reference

There can only be one CMD instruction in a Dockerfile. If you list more than one CMD then only the last CMD will take effect.

The main purpose of a CMD is to provide defaults for an executing container.

Answer 2

Try taking out the mkdir step. You also need to set the working directory.