docker-compose-up-remote-env

#!/bin/bash
# Starts a docker service container (with the same name as the image)
# for the CircleCI remote docker environment.
# In this environment volumes cannot be mounted from local folder
# (they can still be mounted between containers), so we need to copy files manually
# to fresh containers.
# See https://discuss.circleci.com/t/copying-files-to-docker-compose-container/12837
#
# Usage:
# $ docker-compose-up-remote-env.sh analytics
# (instead of: docker-compose up analytics)

# e: Exit immediately if a command exits with a non-zero error status.
# x: Print commands before executing them.
set -ex

readonly SERVICE=$1
readonly GIVEN_CONTAINER_ID=$2
if [ -n "$GIVEN_CONTAINER_ID" ]; then
  readonly CONTAINER_ID=$GIVEN_CONTAINER_ID
else
  readonly CONTAINER_ID="$SERVICE-$CIRCLE_BUILD_NUM"
fi
echo "Start container $CONTAINER_ID of service '$SERVICE' on the CircleCI remote docker environment"

echo '1. Alter docker-compose.yml to remove volumes and entrypoint.'
# Save which volumes should be created in the service.
cat docker-compose.yml | shyaml get-value services.$SERVICE.volumes '' > volumes-$CONTAINER_ID.txt
# Save entrypoints for the service.
readonly ENTRYPOINT="$(cat docker-compose.yml | shyaml get-value services.$SERVICE.entrypoint '')"
# Remove declared entrypoints and volumes in services.
# The original file will be saved in docker-compose.yml.bak).
sed -E '/^\ +(entrypoint:.*|volumes:|- \..*)\ *$/d' docker-compose.yml > docker-compose-altered-$CONTAINER_ID.yml

echo '2. Start service without volumes and entrypoint.'
# We run a random command (here 'ls') before running 'sleep 1000' to make sure 'sleep' doesn't get
# the pid '1' which would make it impossible to kill the process at tear down.
docker-compose -f docker-compose-altered-$CONTAINER_ID.yml run --name $CONTAINER_ID --no-deps -d $SERVICE /bin/sh -c "ls; sleep 1000"

echo '3. Copy files declared as required volumes to the new service container.'
cat volumes-$CONTAINER_ID.txt | while read line; do
  # Split ./frontend/cfg:/usr/app/cfg:ro into ./frontend/cfg and /usr/app/cfg
  if [[ "$line" =~ ^-[[:space:]]([^:]+):([^:]+) ]]; then
    SRC="${BASH_REMATCH[1]}"
    DST="${BASH_REMATCH[2]}"
    if [ -d "$SRC" ]; then
      # If the item is a directory:
      # We create the destination folder and will fill it with the content of the source folder.
      PATH_TO_CREATE="$DST"
      # docker cp needs '/.' to be added at the end of folder paths
      # in order to copy the content of the folder and not the parent folder as well.
      SRC="$SRC/."
    elif [ -f "$SRC" ]; then
      # If the item is a file:
      # We create a parent folder for the destination file
      PATH_TO_CREATE="$(dirname "$DST")"
    else
      echo "WARNING: $SRC does not exist in the source file system."
      continue
    fi
    docker exec $CONTAINER_ID mkdir -p "$PATH_TO_CREATE"
    docker cp "$SRC" "$CONTAINER_ID:$DST"
  else
    echo "ERROR: Wrong format in volumes for $SERVICE: $line"
    exit 1
  fi
done

echo "4. Run entrypoint $ENTRYPOINT."
# Our entrypoint are actually commands that we want to run before the actual commands
# (as opposed to regular entrypoints) therefore it's OK to run it here.
if [ -n "$ENTRYPOINT" ]; then
  docker exec -t $CONTAINER_ID $ENTRYPOINT
else
  echo 'No entrypoint to run.'
fi

echo '5. Clean up tmp files.'
rm volumes-$CONTAINER_ID.txt
rm docker-compose-altered-$CONTAINER_ID.yml

echo "Container $CONTAINER_ID is ready."