Import PGP keys in a Git repository from GitHub

gpghub.sh

#!/usr/bin/env bash

OWNER="$1"
REPO="$2"

declare -A PROCESSED

function import_github_pgp() {
    local github_login="$1"
    printf 'Importing PGP key of GitHub user %s\n' "$github_login"
    curl "https://github.com/$github_login.gpg" | gpg --import
}

function github_login_from_commit() {
    local commit_hash="$1"
    local response
    if ! response="$(gh api "repos/$OWNER/$REPO/commits/$commit_hash")"; then
        printf 'Failed to retrieve info of commit %s\n' "$commit_hash"
        return 1
    fi
    local verified
    verified="$(jq -r .commit.verification.verified <<<"$response")"
    if [[ "$verified" != "true" ]]; then
        printf 'Commit %s is not verified\n' "$commit_hash"
        return 1
    fi
    local github_login
    github_login="$(jq -r .author.login <<<"$response")"
    printf '%s' "$github_login"
}

if [[ -z "$OWNER" ]] || [[ -z "$REPO" ]]; then
    owner_repo="$(git remote get-url --no-push origin | sed -n 's/.*[:\/]\([-_a-zA-Z0-9]\+\)\/\([-_a-zA-Z0-9]\+\)\(\.git\)\?$/\1 \2/p')"
    if [[ -z "$owner_repo" ]]; then
        printf 'Please provide owner and repository name\n'
        exit 1
    fi
    OWNER="$(cut -d ' ' -f 1 <<<"$owner_repo")"
    REPO="$(cut -d ' ' -f 2 <<<"$owner_repo")"
    printf 'Detected repository https://github.com/%s/%s, continue? [y/n] ' "$OWNER" "$REPO"
    read -n1 -r
    printf '\n'
    if [[ "$REPLY" != 'y' ]]; then
        exit 0
    fi
fi

while read -r commit_hash; do
    printf 'Processing commit %s\n' "$commit_hash"
    email="$(git show -s --format='%ae' "$commit_hash")"
    primary_key="$(git show -s --format='%GP' "$commit_hash")"
    if [[ -n "${PROCESSED[$primary_key]}" ]]; then
        printf 'Skipping commit %s since key %s for author email %s has been processed\n' "$commit_hash" "$primary_key" "$email"
        continue
    fi
    PROCESSED["$primary_key"]=1
    if github_login="$(github_login_from_commit "$commit_hash")" && [[ -n "$github_login" ]]; then
        import_github_pgp "$github_login"
    fi
done < <(git log --format='%H %G?' | sed -u -n 's/ E$//p')