A gpgparticipants(1) helper script. The idea is to not import the keys you have initially, but only after the ksp-file.txt has been verified as correct.

ksphelper

#!/usr/bin/env bash

set -euo pipefail

help() {
    cat<<HELP 2>&1
USAGE:
    ksphelper <party name> <keymaster> <keysfile>

    ksphelper helps create a gpgparticipants file from a list of keys.
    Outputs a ksp-text.txt in the current directory from gpgparticipants
    and won't mess with your normal gpg keyring to do it.

OPTIONS:
    <party name>    Name for your keysigning party, passed as title to
                    gpgparticipants(1)
    <keymaster>     KSP organizer in the format: "Name <email@domain.tld>",
                    passed as organizer to gpgparticipants(1)
    <keysfile>      Path to text file that contains the keys of all
                    participants, one per line, comments and blank lines
                    are ignored.

EXAMPLE:

    ksphelper "WMFRelEng" "Tyler Cipriani <tcipriani@wikimedia.org>" keys
HELP
}

if (( $# < 3 )); then
    help
    exit 1
fi

KSP_NAME="$1"
KEYMASTER="$2"
KEYS_FILE="$3"
KEYRING_DIR="$(mktemp -d -q --suffix=_ksphelper)"
KEYRING="pubring.kbx"

touch "${KEYRING_DIR}/${KEYRING}"

# Grab all the keys into a local keychain
grep -v '^#' keys | \
grep -v '^\s*$' | xargs gpg \
    --no-options \
    --no-default-keyring \
    --keyring="${KEYRING_DIR}/${KEYRING}" \
    --recv-keys

grep -v '^#' keys | \
grep -v '^\s*$' | GNUPGHOME="$KEYRING_DIR" gpgparticipants \
    - ksp-file.txt "$(date --iso=seconds)" "$KEYMASTER" "$KSP_NAME"

rm -rf "$KEYRING_DIR"