discordeno/src/helpers/channels/follow_channel.ts

import { rest } from "../../rest/rest.ts";
import { DiscordFollowedChannel } from "../../types/channels/followed_channel.ts";
import { endpoints } from "../../util/constants.ts";
import { requireBotChannelPermissions } from "../../util/permissions.ts";

/** Follow a News Channel to send messages to a target channel. Requires the `MANAGE_WEBHOOKS` permission in the target channel. Returns the webhook id. */
export async function followChannel(
  sourceChannelId: string,
  targetChannelId: string,
) {
  await requireBotChannelPermissions(targetChannelId, ["MANAGE_WEBHOOKS"]);

  const data =
    (await rest.runMethod("post", endpoints.CHANNEL_FOLLOW(sourceChannelId), {
      webhook_channel_id: targetChannelId,
    })) as DiscordFollowedChannel;

  return data.webhook_id;
}