feat: only allow voting once

Author: eug-vs

models/polls/poll.model.ts

@@ -1,5 +1,18 @@
 import { Model, model } from 'mongoose';
 import { PollSchema, pollSchema } from './poll.schema';
 
+pollSchema.methods.vote = function(userId: string, which: 'left' | 'right'): PollSchema {
+  const participants = ['left', 'right'].reduce((acc, option) => {
+    const { votes } = this.contents[option];
+    return acc.concat(votes);
+  }, []);
+
+  if (!participants.indexOf(userId) === -1) {
+    this.contents[which].votes.push(userId);
+  }
+
+  return this.save();
+}
+
 export default model<PollSchema, Model<PollSchema>>('Poll', pollSchema);
 

models/polls/poll.schema.ts

@@ -11,7 +11,7 @@ export interface PollSchema extends Document {
     right: ImageDataSchema;
   };
   authorId: string;
-  vote: (userId: string, which: 'left' | 'right') => void;
+  vote: (userId: string, which: 'left' | 'right') => PollSchema;
 }
 
 export const imageDataSchema = {

services/votes/votes.class.ts

@@ -5,11 +5,8 @@ export default class Votes {
   async create(data: any, params: any): Promise<PollSchema | null> {
     const poll = await PollModel.findById(params.route.id);
     if (poll) {
-      const which: 'left' | 'right' = data.which;
-      const { user } = params;
-      poll.contents[which].votes.push(user._id);
-      poll.save();
-      return poll.toObject();
+      const updatedPoll = await poll.vote(params.user._id, data.which);
+      return updatedPoll.toObject();
     }
     return null;
   }