Rearrange code (self-review)

m2d/actions/emoji-sheet.js

@@ -0,0 +1,36 @@
+// @ts-check
+
+const assert = require("assert")
+const fetch = require("node-fetch").default
+
+const utils = require("../converters/utils")
+const {sync} = require("../../passthrough")
+
+/** @type {import("../converters/emoji-sheet")} */
+const emojiSheetConverter = sync.require("../converters/emoji-sheet")
+
+/**
+ * Downloads the emoji from the web and converts to uncompressed PNG data.
+ * @param {string} mxc a single mxc:// URL
+ * @returns {Promise<Buffer | undefined>} uncompressed PNG data, or undefined if the downloaded emoji is not valid
+ */
+async function getAndConvertEmoji(mxc) {
+	const abortController = new AbortController()
+
+	const url = utils.getPublicUrlForMxc(mxc)
+	assert(url)
+
+	/** @type {import("node-fetch").Response} */
+	// If it turns out to be a GIF, we want to abandon the connection without downloading the whole thing.
+	// If we were using connection pooling, we would be forced to download the entire GIF.
+	// So we set no agent to ensure we are not connection pooling.
+	// @ts-ignore the signal is slightly different from the type it wants (still works fine)
+	const res = await fetch(url, {agent: false, signal: abortController.signal})
+	return emojiSheetConverter.convertImageStream(res.body, () => {
+		abortController.abort()
+		res.body.pause()
+		res.body.emit("end")
+	})
+}
+
+module.exports.getAndConvertEmoji = getAndConvertEmoji

m2d/actions/send-event.js

@@ -17,8 +17,8 @@ const eventToMessage = sync.require("../converters/event-to-message")
 const api = sync.require("../../matrix/api")
 /** @type {import("../../d2m/actions/register-user")} */
 const registerUser = sync.require("../../d2m/actions/register-user")
-/** @type {import("../converters/emoji-sheet")} */
-const emojiSheet = sync.require("../converters/emoji-sheet")
+/** @type {import("../actions/emoji-sheet")} */
+const emojiSheet = sync.require("../actions/emoji-sheet")
 
 /**
  * @param {DiscordTypes.RESTPostAPIWebhookWithTokenJSONBody & {files?: {name: string, file: Buffer | Readable}[], pendingFiles?: ({name: string, url: string} | {name: string, url: string, key: string, iv: string} | {name: string, buffer: Buffer | Readable})[]}} message