#!/bin/sh -e

if [ $# -lt 2 ] || [ $# -gt 3 ]; then

    cat >&2 <<EOD

usage: $0 CONFIG_FILE FROM_REV [TO_REV]

Runs a database migration from FROM_REV to TO_REV (default: current

working directory parent), using the specified CONFIG_FILE (.ini file).

Test is run using a clean Kallithea install, in a temporary virtual

environment. FROM_REV and (optional) TO_REV should be Mercurial revision

identifiers (e.g. changeset hash or a version number tag). The working

directory is not touched, but the database referenced in the config file

will be (re)created.

Only SQLite is available out of the box; for MySQL or PostgreSQL, set

the EXTRA environment variable to the required package(s), and it'll

be installed in the virtual environment. (E.g. EXTRA=MySQL-python or

EXTRA=psycopg2.)

The temporary directory is not removed, allowing follow-up examination

of the upgrade results. It is, however, created in /tmp by default,

which many Linux distributions automatically clean at regular intervals.

EOD

    exit 1

fi

config_file=$(readlink -f "$1")

from_rev=$2

to_rev=$3

source_repo=$(dirname "$(dirname "$(readlink -f "$0")")")

announce() {

    echo

    echo "$1"

    echo

}

quiet_if_ok() (

    local output

    local st

    set +e

    output=$("$@" < /dev/null 2>&1)

    st=$?

    if [ $st -ne 0 ]; then

        echo "$output" >&2

        echo "Command $@ returned exit status $st." >&2

        exit 1

    fi

)

HG() {

    "${HG:-hg}" --repository "$source_repo" "$@"

}

# If upgrading to "current revision", warn if working directory is dirty.

if [ ! "$to_rev" ] && [ "$(HG status -mard)" ]; then

    announce "Warning: Uncommitted changes in working directory will be ignored!"

fi

from_rev_hash=$(HG id --id --rev "${from_rev:-.}")

to_rev_hash=$(HG id --id --rev "${to_rev:-.}")

temp=$(readlink -f "$(mktemp --tmpdir -d 'dbmigrate-test.XXXXXX')")

cat <<EOD

Config file:    $config_file

EOD

sed -n -e 's/^sqlalchemy\.db1\.url *= */Database URL:   /p' "$config_file"

cat <<EOD

Working dir:    $temp

Repository:     $source_repo

Upgrade from:   $from_rev_hash (${from_rev:-current})

Upgrade to:     $to_rev_hash (${to_rev:-current})

Extra packages: ${EXTRA:-(none)}

EOD

mkdir "$temp/repos" # empty

# Enable caching for old pip versions (this will cache the pip upgrade)

# Newer pip versions cache automatically, and don't use this variable.

if [ ! "$PIP_DOWNLOAD_CACHE" ]; then

    export PIP_DOWNLOAD_CACHE=$HOME/.cache/pip/legacy

fi

install_kallithea() {

    local prefix=$1

    local rev=$2

    announce "Installing Kallithea $rev in $prefix..."

    "${VIRTUALENV:-virtualenv}" --quiet "$prefix-env"

    HG archive --rev "$rev" "$prefix"

    (

        cd "$prefix"

        . "$prefix-env/bin/activate"

        pip install --quiet --upgrade pip setuptools mercurial $EXTRA

        pip install --quiet -e .

    )

}

install_kallithea "$temp/from" "$from_rev_hash"

(

    cd "$temp/from"

    . "$temp/from-env/bin/activate"

    announce "Initializing database..."

    quiet_if_ok paster setup-db "$config_file" --repos="$temp/repos" --user=doe --email=doe@example.com --password=123456 --no-public-access --force-yes

    alembic -c "$config_file" current -v

)

install_kallithea "$temp/to" "$to_rev_hash"

(

    cd "$temp/to"

    . "$temp/to-env/bin/activate"

    announce "Commencing database upgrade from shown Alembic revision to head..."

    alembic -c "$config_file" current -v

    alembic -c "$config_file" upgrade head

    announce "Upgrade complete, now at the shown Alembic revision:"

    alembic -c "$config_file" current -v

)