Is there a way to combine Docker images into 1 container?

Question

I have a few Dockerfiles right now.

One is for Cassandra 3.5, and it is FROM cassandra:3.5

I also have a Dockerfile for Kafka, but t is quite a

Answer 1

The following answer applies to docker 1.7 and above:

I would prefer to use --from=NAME and from image as NAME Why? You can use --from=0 and above but this might get little hard to manage when you have many docker stages in dockerfile.

sample example:

FROM golang:1.7.3 as backend
WORKDIR /backend
RUN go get -d -v golang.org/x/net/html  
COPY app.go .
RUN  #install some stuff, compile assets....

FROM golang:1.7.3 as assets
WORKDIR /assets
RUN ./getassets.sh

FROM nodejs:latest as frontend 
RUN npm install
WORKDIR /assets
COPY --from=assets /asets .
CMD ["./app"] 

FROM alpine:latest as mergedassets
WORKDIR /root/
COPY --from=merge ./
COPY --from=backend ./backend .
CMD ["./app"]

Note: Managing dockerfile properly will help to build a docker image must faster. Internally docker usings docker layer caching to help with this process, incase the image have to be rebuilt.