Basic error checking

src/lib/collectors.js

@@ -10,13 +10,16 @@ const timelineEntryCache = new TtlCache(constants.resource_cache_time)
 
 function fetchUser(username) {
 	return requestCache.getOrFetch("user/"+username, () => {
-		return request(`https://www.instagram.com/${username}/`).then(res => res.text()).then(text => {
-			// require down here or have to deal with require loop. require cache will take care of it anyway.
-			// User -> Timeline -> TimelineImage -> collectors -/> User
-			const User = require("./structures/User")
-			const sharedData = extractSharedData(text)
-			const user = new User(sharedData.entry_data.ProfilePage[0].graphql.user)
-			return user
+		return request(`https://www.instagram.com/${username}/`).then(res => {
+			if (res.status === 404) throw constants.symbols.NOT_FOUND
+			else return res.text().then(text => {
+				// require down here or have to deal with require loop. require cache will take care of it anyway.
+				// User -> Timeline -> TimelineImage -> collectors -/> User
+				const User = require("./structures/User")
+				const sharedData = extractSharedData(text)
+				const user = new User(sharedData.entry_data.ProfilePage[0].graphql.user)
+				return user
+			})
 		})
 	})
 }
@@ -24,7 +27,7 @@ function fetchUser(username) {
 /**
  * @param {string} userID
  * @param {string} after
- * @returns {Promise<import("./types").PagedEdges<import("./types").GraphImage>>}
+ * @returns {Promise<import("./types").PagedEdges<import("./types").TimelineEntryN2>>}
  */
 function fetchTimelinePage(userID, after) {
 	const p = new URLSearchParams()
@@ -36,7 +39,7 @@ function fetchTimelinePage(userID, after) {
 	}))
 	return requestCache.getOrFetchPromise("page/"+after, () => {
 		return request(`https://www.instagram.com/graphql/query/?${p.toString()}`).then(res => res.json()).then(root => {
-			/** @type {import("./types").PagedEdges<import("./types").GraphImage>} */
+			/** @type {import("./types").PagedEdges<import("./types").TimelineEntryN2>} */
 			const timeline = root.data.user.edge_owner_to_timeline_media
 			return timeline
 		})
@@ -86,7 +89,12 @@ function fetchShortcodeData(shortcode) {
 		return request(`https://www.instagram.com/graphql/query/?${p.toString()}`).then(res => res.json()).then(root => {
 			/** @type {import("./types").TimelineEntryN3} */
 			const data = root.data.shortcode_media
-			return data
+			if (data == null) {
+				// the thing doesn't exist
+				throw constants.symbols.NOT_FOUND
+			} else {
+				return data
+			}
 		})
 	})
 }

src/lib/constants.js

@@ -16,6 +16,8 @@ module.exports = {
 		TYPE_VIDEO: Symbol("TYPE_VIDEO"),
 		TYPE_GALLERY: Symbol("TYPE_GALLERY"),
 		TYPE_GALLERY_IMAGE: Symbol("TYPE_GALLERY_IMAGE"),
-		TYPE_GALLERY_VIDEO: Symbol("TYPE_GALLERY_VIDEO")
+		TYPE_GALLERY_VIDEO: Symbol("TYPE_GALLERY_VIDEO"),
+		NOT_FOUND: Symbol("NOT_FOUND"),
+		NO_SHARED_DATA: Symbol("NO_SHARED_DATA")
 	}
 }

src/lib/structures/TimelineEntry.js

@@ -19,8 +19,9 @@ class TimelineEntry extends TimelineBaseMethods {
 		/** @type {import("../types").TimelineEntryAll} some properties may not be available yet! */
 		// @ts-ignore
 		this.data = {}
+		const error = new Error("TimelineEntry data was not initalised in same event loop (missing __typename)") // initialise here for a useful stack trace
 		setImmediate(() => { // next event loop
-			if (!this.data.__typename) throw new Error("TimelineEntry data was not initalised in same event loop (missing __typename)")
+			if (!this.data.__typename) throw error
 		})
 		/** @type {string} Not available until fetchExtendedOwnerP is called */
 		this.ownerPfpCacheP = null
@@ -29,8 +30,12 @@ class TimelineEntry extends TimelineBaseMethods {
 	}
 
 	async update() {
-		const data = await collectors.fetchShortcodeData(this.data.shortcode)
-		this.applyN3(data)
+		return collectors.fetchShortcodeData(this.data.shortcode).then(data => {
+			this.applyN3(data)
+		}).catch(error => {
+			console.error("TimelineEntry could not self-update; trying to continue anyway...")
+			console.error("E:", error)
+		})
 	}
 
 	/**

src/lib/utils/body.js

@@ -1,3 +1,4 @@
+const constants = require("../constants")
 const {Parser} = require("./parser/parser")
 
 /**
@@ -5,7 +6,8 @@ const {Parser} = require("./parser/parser")
  */
 function extractSharedData(text) {
 	const parser = new Parser(text)
-	parser.seek("window._sharedData = ", {moveToMatch: true, useEnd: true})
+	const index = parser.seek("window._sharedData = ", {moveToMatch: true, useEnd: true})
+	if (index === -1) throw constants.symbols.NO_SHARED_DATA
 	parser.store()
 	const end = parser.seek(";</script>")
 	parser.restore()