• Emanuele Aina's avatar
    docker-compose: Move PGDATA to a subdir to make permissions work out-of-the-box · 9cf9983c
    Emanuele Aina authored
    We currently bind mount `/var/lib/postgresql/data` to a local folder
    which is assumed to exist with the right permissions, owned by the user
    under which the `postgres` container is run (uid 1000 or the one
    configured with the `RUN_USER` environment variable).
    
    If that's not the case (on a fresh checkout, for instance), you'll
    be left staring at the following error, after the container failed
    to start:
    
        fixing permissions on existing directory /var/lib/postgresql/data ... initdb: could not change permissions of directory "/var/lib/postgresql/data": Operation not permitted
    
    Having things not work out of the box with weird errors is annoying and
    can easily lead to a non-trivial amount of wasted time (hello!).
    
    This is because Docker creates the mount point directories as owned by
    root, so when the Postgres' `initdb` runs as the `postgres` user it
    fails to change the ownership of the directory.
    
    Shipping the empty directory in the repository would work, but git does
    not really understand empty directories.
    
    Sadly, even only putting a `.gitignore` there would make `initdb` complain:
    
        initdb: directory "/var/lib/postgresql/data" exists but is not empty
        It contains a dot-prefixed/invisible file, perhaps due to it being a mount point.
        Using a mount point directly as the data directory is not recommended.
        Create a subdirectory under the mount point.
    
    A solution avoiding the above issues is to ship some files to
    ensure the mount point directory is created with the user permissions
    (assuming the user doing the checkout is uid 1000 or `RUN_USER` is set
    to the right uid) and then set `PGDATA` to point to a subdirectory of
    the user-writable volume mount point, making `initdb` happy.
    Signed-off-by: Emanuele Aina's avatarEmanuele Aina <emanuele.aina@collabora.com>
    9cf9983c
Name
Last commit
Last update
..
data Loading commit data...