If you update the image for a docker-compose config, you can restart each of the containers by running

docker-compose down
docker-compose up -d

Assuming you have a directory structure like the following:

|--- docker-compose-directory
     |--- docker_container1
          |- docker-compose.yml
     |--- docker_container2
          |- docker-compose.yml
     |--- docker_container3
          |- docker-compose.yml

You can write a simple script to traverse each of the directories and restart the container

if [ "$#" -eq 0 ];

        dirlist=$(find $1 -mindepth 1 -maxdepth 1 -type d)

        for dir in $dirlist
                cd $dir
                echo $dir
                docker-compose down
                docker-compose up -d
        cd $1
        echo $1
        docker-compose down
        docker-compose up -d

Save the script as something like restart.sh in the root directory of your docker-compose directory, make the file executable, and run.

This also works if you want to restart just a single docker-compose YML.

#restart all containers
$ ./restart.sh 

#restart a single container
$ ./restart.sh docker_container1