Docker Musings

## Tagging an image
docker tage <image_id> name_of_the_image

#real time logs
docker logs --tail 1 --follow cbceaaea0ef5

# Forcing a rebuild
docker build --no-cache

# publish a port even if it was not expose in the dockerfile
docker run -p <port>

# publish all ports that were explosed in the docker file
docker run -P

# Setting up environment variables
docker run -e WEBAPP_PORT=8000 -e WEBAPP_HOST=www.example.com

# Renaming a container
docker rename <old_name> <new_name>

## using jq with Docker
docker inspect <container_name> | jq .[0] | jq keys

[
  "Architecture",
  "Author",
  "Comment",
  "Config",
  "Container",
  "ContainerConfig",
  "Created",
  "DockerVersion",
  "GraphDriver",
  "Id",
  "Os",
  "Parent",
  "RepoDigests",
  "RepoTags",
  "RootFS",
  "Size",
  "VirtualSize"
]

docker inspect <container_name> | jq .[0] | jq .DockerVersion
"1.12.3"

# using format with docker
docker inspect --format '{{ json .Created }}' <container_id>

# find the port mapping for a container e.g. port 80
docker port <containerID> 80

# manual allocation of port
docker run -d -p host_port:container_port <container>

# Finding the container IP address using format (you can use jq)
docker inspect --format '{{ .NetworkSettings.IPAddress }}' <ContainerID>

docker inspect <ContainerID> | jq .[0] | jq .NetworkSetting.IPAddress

# Removing a docker container
docker rm -f <container_name>

# Create a custm network
docker network create <network name>

##some useful options
--internal # no communication with the outside worlds
--gateway # specify the gateway of choice
--subnet # choose the subnet to use e.g., --subnet 192.168.1.0/24
--ip-range # specify which IPs from the subnet to use
--aux-address # specify reserved addresses not to be used by the network

# Create an Overlay network
docker network create mynet --driver overlay

# Create a container link
docker run -it --link datastore:redis alpine ping redis

# connecting a volume on the host to the container
docker run -d -v $(pwd):/src username/application_name

# create  a volume from anothe container (data-containers usecase)
docker run --volumes-from <source_container> <destination_container> <commands>
# list available volume
docker volumes ls

# craete named volumes
docker volume create --name <volume_name>

# Fetch an image called node
FROM node
# Maintainer
MAINTAINER maintainer@email.com
# Run commands inside the container (typicall used for installing packages)
# Each RUN command adds a new Docker layer, so make sure to use them wisely (use RUN Command1 && Command2 && .. CommandN to save layers and storage)
RUN git clone -q https://github.com/docker-practice/test.git && npm install > /dev/null
# Change to a directory called test (this is where CMD commands will be executed )
WORKDIR ~/test
# Expose port 8000 inside the container (that will be mapped by default to another host port)
EXPOSE 8000
# CMD defines the command to be executed when the container is started
CMD ["start"]
# ENTRY point sets the default container command
ENTRYPOINT ["npm"]

#Note_1: Use ENTRY Point when you need to run your container as an executable and use CMD to provide arguments to ENTRYPOINT commands.

#Note_2: you can only use one CMD and one ENTRYPOINT per Dockerfile

version: '2'
services:
  web:
    build: .
    ports:
    - "5000:5000"
    volumes:
    - .:/code
    - logvolume01:/var/log
    links:
    - redis
  redis:
    image: redis
volumes:
  logvolume01: {}

sudo curl -L https://github.com/docker/compose/releases/download/1.11.1/docker-compose-`uname -s`-`uname -m` > /usr/local/bin/docker-compose

chmod +x /usr/local/bin/docker-compose

##Build your compose setup
docker-compose build

## Run it
docker-compose up

## Run it in detached mode
docker-compose up -d

## Check the status of the compose containers
docker-compose ps

## kill / remove your compose setup
docker-compose kill
docker-compose rm

docker run -it --link datastore:redis alpine ping redis

# Creating Network Alias
docker run -d --name prod-es-1 --net-alias search --net prod elasticsearch
docker run -d --name prod-es-2 --net-alias search --net prod elasticsearch

docker network create mynet --driver overlay