How to Find All Image Tags of a Running Docker Container

How can I list all tags for a Docker image on a remote registry?

Update: sadly this solution will no longer work because Docker has deprecated the v1 API.

I got the answer from here . Thanks a lot! :)

Just one-line-script:(find all the tags of debian)

wget -q https://registry.hub.docker.com/v1/repositories/debian/tags -O -  | sed -e 's/[][]//g' -e 's/"//g' -e 's/ //g' | tr '}' '\n'  | awk -F: '{print $3}'

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UPDATE
Thanks for @degelf's advice.
Here is the shell script.

#!/bin/bash

if [ $# -lt 1 ]
then
cat << HELP

dockertags  --  list all tags for a Docker image on a remote registry.

EXAMPLE: 
    - list all tags for ubuntu:
       dockertags ubuntu

    - list all php tags containing apache:
       dockertags php apache

HELP
fi

image="$1"
tags=`wget -q https://registry.hub.docker.com/v1/repositories/${image}/tags -O -  | sed -e 's/[][]//g' -e 's/"//g' -e 's/ //g' | tr '}' '\n'  | awk -F: '{print $3}'`

if [ -n "$2" ]
then
    tags=` echo "${tags}" | grep "$2" `
fi

echo "${tags}"

You can just create a new file name, dockertags, under /usr/local/bin (or add a PATH env to your .bashrc/.zshrc), and put that code in it.
Then add the executable permissions(chmod +x dockertags).

Usage:

dockertags ubuntu ---> list all tags of ubuntu

dockertags php apache ---> list all php tags php containing 'apache'

How to get the image name of a docker container from inside the container

This type of information/metadata is not passed into the container by default. There are 2 reasons for this.

1. if every metadata about the container was passed into the container, it could potentially pose a security risk when someone breaks into it
2. container shouldn't need this kind of information anyway

The reason why you can get access to container's ID from within the container is simply because it is used as the container's hostname by default. If you would specify hostname when running the container with container run --hostname ..., you wouldn't have access to the ID either.

I don't know why you need this information but the only way to get it when you are inside of the container is to first pass it to the container in one way or another. For example via an environment variable.

If you don't have access to this information from the outside of the container (which seems strange if you are able to use docker exec), you will not get it from the running container.

How to see docker image contents

If the image contains a shell, you can run an interactive shell container using that image and explore whatever content that image has. If sh is not available, the busybox ash shell might be.

For instance:

docker run -it image_name sh

Or following for images with an entrypoint

docker run -it --entrypoint sh image_name

Or if you want to see how the image was built, meaning the steps in its Dockerfile, you can:

docker image history --no-trunc image_name > image_history

The steps will be logged into the image_history file.

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