nixos/olivetin: use yq-go to merge config files (#415106)

      inherit (cfg) path;

      preStart = ''

        tmp="$(mktemp -d)"

        trap 'rm -rf "$tmp"' EXIT

        cd "$tmp"

        cp ${settingsFormat.generate "olivetin-config.yaml" cfg.settings} config.yaml

        chmod +w config.yaml

        for ((i=0; i < ${toString (lib.length cfg.extraConfigFiles)}; i++)); do

          ${lib.getExe pkgs.yq} -yi '

            def merge($y):

              . as $x |

              if ($x | type == "object") and ($y | type == "object") then

                $x + $y + with_entries(select(.key | in($y)) | .key as $key | .value |= merge($y[$key]))

              elif ($x | type == "array") and ($y | type == "array") then

                $x + $y

              else

                $y

              end;

            merge($f | fromjson)

          ' config.yaml --rawfile f <(${lib.getExe pkgs.yq} -c . "$CREDENTIALS_DIRECTORY/config-$i.yaml")

        done

        chmod -w config.yaml

        shopt -s nullglob

        tmp="$(mktemp)"

        ${lib.getExe pkgs.yq-go} eval-all '. as $item ireduce ({}; . *+ $item)' \

          ${settingsFormat.generate "olivetin-config.yaml" cfg.settings} \

          $CREDENTIALS_DIRECTORY/config-*.yaml > "$tmp"

        chmod -w "$tmp"

        mkdir -p /run/olivetin/config

        mv config.yaml /run/olivetin/config/config.yaml

        mv "$tmp" /run/olivetin/config/config.yaml

      '';

      serviceConfig = {