Function resolveSlackUserDisplayNames

server/src/slack/client.ts:316–341

(
  slackUserIds: string[],
  concurrency = 5
)

 * Returns a map of user ID -> display name.
 */
export async function resolveSlackUserDisplayNames(
  slackUserIds: string[],
  concurrency = 5
): Promise<Record<string, string>> {
  const results: Record<string, string> = {};
  const uniqueIds = [...new Set(slackUserIds)];

  // Process in batches to avoid rate limiting
  for (let i = 0; i < uniqueIds.length; i += concurrency) {
    const batch = uniqueIds.slice(i, i + concurrency);
    const batchResults = await Promise.all(
      batch.map(async (userId) => {
        const resolved = await resolveSlackUserDisplayName(userId);
        return { userId, displayName: resolved?.display_name };
      })
    );

    for (const { userId, displayName } of batchResults) {
      if (displayName) {
        results[userId] = displayName;
      }
    }
  }

  return results;
}

/**
 * Look up a user by email address