Docker bits and pieces

Docker & localhost

# Access to localhost through docker.for.win.localhost

# A hack to hit that IP as localhost 
# note that ip may change so could be fragile? 
docker run --add-host localhost:192.168.65.2 ... etc

#dynamically as part of dockerfile
#Ugly but working for local stuff. 
ENTRYPOINT echo "$(dig +short docker.for.win.host.internal) localhost" >> /etc/hosts && exec python ./end2end_dev.py

Docker cmd line

#Docker output , no wrap, less allows horizontal scrolling
λ: docker ps -a | less -S

#follow logs
λ: docker logs x1y2z3 -f

#bash in an image 
λ: docker exec -it 1103e bash

Docker.Debug

# various ways to debug a container, but this is useful to keep it running: 
ENTRYPOINT ["/bin/bash", "-c", "while true; do sleep 10; date; done"]
# or 
ENTRYPOINT ["bash", "-c", "sleep 1d"]

Docker.Timezones

# set NZ timezone for jenkins container
# This assumes the image has TZ info in /usr/share/zoneinfo/
ENV TZ=Pacific/Auckland
RUN ln -snf /usr/share/zoneinfo/$TZ /etc/localtime && echo $TZ > /etc/timezone

# Though maybe this is a fuller solution
ENV TZ Asia/Kuala_Lumpur

RUN echo $TZ > /etc/timezone && \
    apt-get update && apt-get install -y tzdata && \
    rm /etc/localtime && \
    ln -snf /usr/share/zoneinfo/$TZ /etc/localtime && \
    dpkg-reconfigure -f noninteractive tzdata && \
    apt-get clean

# OR, mount at runtime 
# docker run -v /etc/localtime:/etc/localtime ...

# Also at runtime, (for vanilla unix) just set TZ env variable? 
# sudo docker run -i -t -e TZ=Europe/London centos /bin/bash