Function postToGroupChannel

server/src/notifications/wg-slack.ts:38–64

(
  groupId: string,
  options: SlackBlockMessage,
)

 * Returns `{ ok: false, error: 'no-channel' }` if no channel exists in the chain.
 */
export async function postToGroupChannel(
  groupId: string,
  options: SlackBlockMessage,
): Promise<PostToGroupChannelResult> {
  const { channelId, viaParent, group } = await workingGroupDb.resolveNotificationChannel(groupId);

  if (!channelId || !group) {
    logger.warn({ groupId }, 'No Slack channel resolvable for working group');
    return { ok: false, error: 'no-channel' };
  }

  // If a private subgroup is falling back to a public parent's channel, flag it —
  // posting private content to a public channel is almost certainly a leak.
  if (viaParent && group.is_private) {
    logger.warn(
      { groupId, groupSlug: group.slug, parentChannelId: channelId },
      'Private subgroup posting via parent channel — configure its own channel to keep content private',
    );
  }

  const text = viaParent && options.text
    ? `[${group.name}] ${options.text}`
    : options.text;

  const result = await sendChannelMessage(channelId, { ...options, text });
  return { ...result, via_parent: viaParent, resolved_channel_id: channelId };
}