Zero-downtime mise upgrade

mise-safe-upgrade

#!/bin/sh

set -e

config=$HOME/.config/mise/config.toml
config_bak=${config%.toml}.bak.toml

while getopts "f:" opt; do
    case $opt in
        f)
            config=$OPTARG
            ;;
        \?)
            echo "Usage: $0 [-c config] [tool...]"
            exit 1
            ;;
    esac
done

shift $((OPTIND - 1))

if [ -f "$config_bak" ]; then
    echo "$config_bak exists; upgrade seems to be in progress."
    exit 1
fi

cd "$(dirname "$config")"

# Get outdated tools.
outdated=$(mise outdated --json "$@")
if [ "$outdated" = '{}' ]; then
    echo Nothing to upgrade.
    exit
fi

# Pin the tools to the currently installed versions while new versions are being installed.
cp -p "$config" "$config_bak"
mise use --path "$config" \
     $(printf %s "$outdated" | jq -r 'to_entries | map("\(.key)@\(.value.current // .value.latest)") | .[]')

# Install the latest versions.
mise install \
     $(printf %s "$outdated" | jq -r 'to_entries | map("\(.key)@\(.value.latest)") | .[]')

mv "$config_bak" "$config"