Mount from host filesystem

[Brandl]

Yes, I know this is against Dockerfile best practice, but it's really required in my usecase. For backup and portability reasons all Docker container share a specific folder with the host filesystem. The approach so far was to manually create data-only-container and share them with the actual container.

I am willing to implement this feature into octohost, if you agree to one of this implementations:

1. "magic" Dockerfile comment using "-v"-argument -> # MOUNT_FROM_HOST /docker/cont1storage
2. If # VOLUMES_FROM is specified and "currentgitreponame_data" doesn't exist, spin one up

Do you agree, that this feature would be useful?
Which implementation do you prefer?

[darron]

I think the MOUNT_FROM_HOST would be best - that keeps it separate from the old VOLUMES_FROM implementation that I'm not super fond of anyways.

[Brandl]

Thats strange, it works perfectly if I leave out the echo in the following code:

    MOUNT_FROM_HOST=$(grep -i "^# MOUNT_FROM_HOST" $DOCKERFILE)
    if [ -n "$MOUNT_FROM_HOST" ]
    then
      HOST_PATH=$(grep -i "^# MOUNT_FROM_HOST" $DOCKERFILE | awk '{ print $3 }')
      CONTAINER_PATH=$(grep -i "^# MOUNT_FROM_HOST" $DOCKERFILE | awk '{ print $4 }')
      if [ -n "$CONTAINER_PATH" ]
      then
        MOUNT_PATH="$HOST_PATH:$CONTAINER_PATH"
      else
        MOUNT_PATH="$HOST_PATH:$HOST_PATH"
      fi

      RUN_OPTIONS="$RUN_OPTIONS -v $MOUNT_PATH"
      echo "Mounting at $MOUNT_PATH"
    fi

Otherwise it throws a error "Image with the name Mounting not found"(or something like that).

Any ideas?

[darron]

You shouldn't likely echo in there - it's building a bunch of command line flags for the docker run command.

[aussielunix]

I had implemented this a little while ago but only pushed it this morning.
I too learnt that you can not echo feedback.

👍 to having this merged in.

[Brandl]

Kinda confusing, because there actually is an echo, inside the "linking container"-block, which I used as a snippet. Nonetheless, it works as expected and I have been using it in Production since a week, so it could be merged:
25e8976 [#69]

For the docs:

# MOUNT_FROM_HOST /etc/data

results in -v /etc/data:/etc/data, which mounts /etc/data to the container filesystem

# MOUNT_FROM_HOST /host/data/docker-data /docker/container/data

results in -v /host/data/docker-data:/docker/container/data, which mounts/host/data/docker-data from the host filesystem to /docker/container/data on the container

(Hint: be aware, that file owner and permissions have to match in order for the container to read/write on the mounted folder!)

[NigelThorne]

This is exactly what I need to get shipyard working. Please can we get this into master? Is there anything I can do to help?

[darron]

I will merge as soon as I can. Will try to merge tomorrow.

Traveling at the moment with really crappy hotel internet.

[NigelThorne]

Thanks. I'm loving octohost.

---

"Man, I'm going to have so many chickens when this lot hatch!"

On Wed, Sep 24, 2014 at 12:21 PM, darron froese notifications@github.com
wrote:

I will merge as soon as I can. Will try to merge tomorrow.

Traveling at the moment with really crappy hotel internet.

—
Reply to this email directly or view it on GitHub
#68 (comment).