# Dockerfile Basics
Encapsulate your application within a container that has a runtime environment set up correctly.
A docker image is required to create this container, and a Dockerfile is what you need to build this image.
A Dockerfile generally:
- Specifies what the runtime environment your application needs (e.g. Nodejs). A common practice is to pull an existing docker ‘base image’.
- Allows you to run shell commands
- Specifies files (source code) to copy into your container for your application to run
- Specifies which port your application is publishing to
- Includes the command required to run your app
FROM node:8-alpine
# prepare project directory within container
RUN mkdir -p /opt/nats-streaming-console/
# Specifies the current working directory. RUN or cd commands will use this directory as reference point
WORKDIR /opt/nats-streaming-console/
# Copy source code into container
COPY <insert/source/code/path> /opt/nats-streaming-console/
# install dependencies, build application
RUN npm install
RUN npm run build-css
RUN npm run build
# application will publish to this port
EXPOSE 8282
#command to run application
CMD ["node", "server"]
With the file ready, you could create a Docker image (in your directory with Dockerfile) docker build -t <insert img name> .
Posted on: Fri, 02 Nov 2018 06:21:11 GMT