From 11190f56ad85a12faaa3653f8743dd75948ff11e Mon Sep 17 00:00:00 2001
From: otofune <otofune@gmail.com>
Date: Sun, 5 Nov 2017 22:13:28 +0900
Subject: [PATCH] serializers/post - run promises in parallel

now w/ opts.detail, returns my_reaction field as 'null' w/ no reaction
(before: field appears w/ some reaction)
---
 package.json                |   1 +
 src/api/serializers/post.ts | 122 ++++++++++++++++++++----------------
 2 files changed, 70 insertions(+), 53 deletions(-)

diff --git a/package.json b/package.json
index 051eb1cb8..1e6e8d813 100644
--- a/package.json
+++ b/package.json
@@ -95,6 +95,7 @@
     "webpack": "3.8.1"
   },
   "dependencies": {
+    "@prezzemolo/rap": "^0.1.0",
     "accesses": "2.5.0",
     "animejs": "2.2.0",
     "autwh": "0.0.1",
diff --git a/src/api/serializers/post.ts b/src/api/serializers/post.ts
index b2c54e9df..352932acf 100644
--- a/src/api/serializers/post.ts
+++ b/src/api/serializers/post.ts
@@ -12,6 +12,7 @@ import serializeChannel from './channel';
 import serializeUser from './user';
 import serializeDriveFile from './drive-file';
 import parse from '../common/text';
+import rap from '@prezzemolo/rap'
 
 /**
  * Serialize a post
@@ -70,21 +71,21 @@ const self = (
 	}
 
 	// Populate user
-	_post.user = await serializeUser(_post.user_id, meId);
+	_post.user = serializeUser(_post.user_id, meId);
 
 	// Populate app
 	if (_post.app_id) {
-		_post.app = await serializeApp(_post.app_id);
+		_post.app = serializeApp(_post.app_id);
 	}
 
 	// Populate channel
 	if (_post.channel_id) {
-		_post.channel = await serializeChannel(_post.channel_id);
+		_post.channel = serializeChannel(_post.channel_id);
 	}
 
 	// Populate media
 	if (_post.media_ids) {
-		_post.media = await Promise.all(_post.media_ids.map(fileId =>
+		_post.media = Promise.all(_post.media_ids.map(fileId =>
 			serializeDriveFile(fileId)
 		));
 	}
@@ -92,82 +93,97 @@ const self = (
 	// When requested a detailed post data
 	if (opts.detail) {
 		// Get previous post info
-		const prev = await Post.findOne({
-			user_id: _post.user_id,
-			_id: {
-				$lt: id
-			}
-		}, {
-			fields: {
-				_id: true
-			},
-			sort: {
-				_id: -1
-			}
-		});
-		_post.prev = prev ? prev._id : null;
+		_post.prev = (async () => {
+			const prev = Post.findOne({
+				user_id: _post.user_id,
+				_id: {
+					$lt: id
+				}
+			}, {
+				fields: {
+					_id: true
+				},
+				sort: {
+					_id: -1
+				}
+			});
+			return prev ? prev._id : null;
+		})()
 
 		// Get next post info
-		const next = await Post.findOne({
-			user_id: _post.user_id,
-			_id: {
-				$gt: id
-			}
-		}, {
-			fields: {
-				_id: true
-			},
-			sort: {
-				_id: 1
-			}
-		});
-		_post.next = next ? next._id : null;
+		_post.next = (async () => {
+			const next = await Post.findOne({
+				user_id: _post.user_id,
+				_id: {
+					$gt: id
+				}
+			}, {
+				fields: {
+					_id: true
+				},
+				sort: {
+					_id: 1
+				}
+			});
+			return next ? next._id : null;
+		})()
 
 		if (_post.reply_id) {
 			// Populate reply to post
-			_post.reply = await self(_post.reply_id, meId, {
+			_post.reply = self(_post.reply_id, meId, {
 				detail: false
 			});
 		}
 
 		if (_post.repost_id) {
 			// Populate repost
-			_post.repost = await self(_post.repost_id, meId, {
+			_post.repost = self(_post.repost_id, meId, {
 				detail: _post.text == null
 			});
 		}
 
 		// Poll
 		if (meId && _post.poll) {
-			const vote = await Vote
-				.findOne({
-					user_id: meId,
-					post_id: id
-				});
+			_post.poll = (async (poll) => {
+				const vote = await Vote
+					.findOne({
+						user_id: meId,
+						post_id: id
+					});
 
-			if (vote != null) {
-				const myChoice = _post.poll.choices
-					.filter(c => c.id == vote.choice)[0];
+				if (vote != null) {
+					const myChoice = poll.choices
+						.filter(c => c.id == vote.choice)[0];
 
-				myChoice.is_voted = true;
-			}
+					myChoice.is_voted = true;
+				}
+
+				return poll
+			})(_post.poll)
 		}
 
 		// Fetch my reaction
 		if (meId) {
-			const reaction = await Reaction
-				.findOne({
-					user_id: meId,
-					post_id: id,
-					deleted_at: { $exists: false }
-				});
+			_post.my_reaction = (async () => {
+				const reaction = await Reaction
+					.findOne({
+						user_id: meId,
+						post_id: id,
+						deleted_at: { $exists: false }
+					});
 
-			if (reaction) {
-				_post.my_reaction = reaction.reaction;
-			}
+				if (reaction) {
+					return reaction.reaction;
+				}
+
+				return null
+			})();
 		}
 	}
 
+	// resolve promises in _post object
+	_post = await rap(_post)
+
 	resolve(_post);
 });