hippofish/src/server/api/endpoints/users/get_frequently_replied_users.ts
2018-04-24 18:13:06 +09:00

99 lines
2 KiB
TypeScript

/**
* Module dependencies
*/
import $ from 'cafy'; import ID from '../../../../cafy-id';
import Note from '../../../../models/note';
import User, { pack } from '../../../../models/user';
module.exports = (params, me) => new Promise(async (res, rej) => {
// Get 'userId' parameter
const [userId, userIdErr] = $(params.userId).type(ID).$;
if (userIdErr) return rej('invalid userId param');
// Get 'limit' parameter
const [limit = 10, limitErr] = $(params.limit).optional.number().range(1, 100).$;
if (limitErr) return rej('invalid limit param');
// Lookup user
const user = await User.findOne({
_id: userId
}, {
fields: {
_id: true
}
});
if (user === null) {
return rej('user not found');
}
// Fetch recent notes
const recentNotes = await Note.find({
userId: user._id,
replyId: {
$exists: true,
$ne: null
}
}, {
sort: {
_id: -1
},
limit: 1000,
fields: {
_id: false,
replyId: true
}
});
// 投稿が少なかったら中断
if (recentNotes.length === 0) {
return res([]);
}
const replyTargetNotes = await Note.find({
_id: {
$in: recentNotes.map(p => p.replyId)
},
userId: {
$ne: user._id
}
}, {
fields: {
_id: false,
userId: true
}
});
const repliedUsers = {};
// Extract replies from recent notes
replyTargetNotes.forEach(note => {
const userId = note.userId.toString();
if (repliedUsers[userId]) {
repliedUsers[userId]++;
} else {
repliedUsers[userId] = 1;
}
});
// Calc peak
let peak = 0;
Object.keys(repliedUsers).forEach(user => {
if (repliedUsers[user] > peak) peak = repliedUsers[user];
});
// Sort replies by frequency
const repliedUsersSorted = Object.keys(repliedUsers).sort((a, b) => repliedUsers[b] - repliedUsers[a]);
// Extract top replied users
const topRepliedUsers = repliedUsersSorted.slice(0, limit);
// Make replies object (includes weights)
const repliesObj = await Promise.all(topRepliedUsers.map(async (user) => ({
user: await pack(user, me, { detail: true }),
weight: repliedUsers[user] / peak
})));
// Response
res(repliesObj);
});