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ERROR:

core.es5.js?0445:1084 ERROR SyntaxError: Unexpected token < in JSON at position 0
    at JSON.parse (<anonymous>

---

SITUATION:

What I am trying to achieve is to pre-select the choice the user already made previously and prevent him from voting twice.

---

CODE:

ponent.html

<article class="panel panel-default">
    <div class="panel-body">
      {{ poll.title }}
      <br>
      <br>
      <form #form="ngForm">
        <fieldset [disabled]="alreadyVotedFor(-1)">
          {{ poll.counter1 }} votes <input type="radio" id="{{ poll.choice1 }}" name="my_radio" value="{{ poll.choice1 }}" (click)="onChoice1(form)" [checked]="alreadyVotedFor(1)">  {{ poll.choice1 }}
          <br>
          {{ poll.counter2 }} votes <input type="radio" id="{{ poll.choice2  }}" name="my_radio" value="{{ poll.choice2 }}" (click)="onChoice2(form)" [checked]="alreadyVotedFor(2)">  {{ poll.choice2 }}
        </fieldset>
      </form>

    </div>
    <footer class="panel-footer">
        <div class="author">
            {{ poll.username }}
        </div>
        <div class="config" *ngIf="belongsToUser()">
            <a (click)="onEdit()">Edit</a>
            <a (click)="onDelete()">Delete</a>
        </div>
    </footer>
</article>

ponent.ts

votes: any;

    ngOnInit() {
        this.pollService.voted(this.poll, localStorage.getItem('userId')).subscribe(
            data => {
                this.votes = data.votes;
                console.log("NGONINIT this.votes: "+ this.votes);
            },
            err => { console.log("NGONINIT ERROR: "+ err) },
            () => { console.log("SUBSCRIBE COMPLETE this.votes: "+ this.votes); }
        );
    }

    alreadyVotedFor(choice: number) {
      let result = "";
      if (this.votes) {
          console.log("THIS.VOTES: "+this.votes);
          for (var i = 0; i < this.votes.length; i ++) {
              if (this.votes[i].poll == this.poll.pollId) {
                  result = "disabled";
                  if (this.votes[i].choice == choice) {
                      result =  "selected";
                  }
              }
          }
      }
      return result;
  }

service

voted(poll: Poll, userID: string) {
    return this.http.get('http://localhost:3000/'+userID)
                    .map(response => response.json());
}

routes/user.js

router.get('/:userid', function (req, res, next) {
  var userId = req.params.userid;
  User.findById(userID, function (err, user) {
    console.log("USER JSON? :"+user.json());
    return res.send(user.json());
  });
});

models/user

var mongoose = require('mongoose');
var Schema = mongoose.Schema;
var mongooseUniqueValidator = require('mongoose-unique-validator');

var schema = new Schema({
    firstName: {type: String, required: true},
    lastName: {type: String, required: true},
    password: {type: String, required: true},
    email: {type: String, required: true, unique: true},
    polls: [{type: Schema.Types.ObjectId, ref: 'Poll'}],
    votes: [{
      poll: {type: Schema.Types.ObjectId, ref: 'Poll'},
      choice: {type: Number},
    }],
});

schema.plugin(mongooseUniqueValidator);

module.exports = mongoose.model('User', schema);

ERROR:

core.es5.js?0445:1084 ERROR SyntaxError: Unexpected token < in JSON at position 0
    at JSON.parse (<anonymous>

---

SITUATION:

What I am trying to achieve is to pre-select the choice the user already made previously and prevent him from voting twice.

---

CODE:

ponent.html

<article class="panel panel-default">
    <div class="panel-body">
      {{ poll.title }}
      <br>
      <br>
      <form #form="ngForm">
        <fieldset [disabled]="alreadyVotedFor(-1)">
          {{ poll.counter1 }} votes <input type="radio" id="{{ poll.choice1 }}" name="my_radio" value="{{ poll.choice1 }}" (click)="onChoice1(form)" [checked]="alreadyVotedFor(1)">  {{ poll.choice1 }}
          <br>
          {{ poll.counter2 }} votes <input type="radio" id="{{ poll.choice2  }}" name="my_radio" value="{{ poll.choice2 }}" (click)="onChoice2(form)" [checked]="alreadyVotedFor(2)">  {{ poll.choice2 }}
        </fieldset>
      </form>

    </div>
    <footer class="panel-footer">
        <div class="author">
            {{ poll.username }}
        </div>
        <div class="config" *ngIf="belongsToUser()">
            <a (click)="onEdit()">Edit</a>
            <a (click)="onDelete()">Delete</a>
        </div>
    </footer>
</article>

ponent.ts

votes: any;

    ngOnInit() {
        this.pollService.voted(this.poll, localStorage.getItem('userId')).subscribe(
            data => {
                this.votes = data.votes;
                console.log("NGONINIT this.votes: "+ this.votes);
            },
            err => { console.log("NGONINIT ERROR: "+ err) },
            () => { console.log("SUBSCRIBE COMPLETE this.votes: "+ this.votes); }
        );
    }

    alreadyVotedFor(choice: number) {
      let result = "";
      if (this.votes) {
          console.log("THIS.VOTES: "+this.votes);
          for (var i = 0; i < this.votes.length; i ++) {
              if (this.votes[i].poll == this.poll.pollId) {
                  result = "disabled";
                  if (this.votes[i].choice == choice) {
                      result =  "selected";
                  }
              }
          }
      }
      return result;
  }

service

voted(poll: Poll, userID: string) {
    return this.http.get('http://localhost:3000/'+userID)
                    .map(response => response.json());
}

routes/user.js

router.get('/:userid', function (req, res, next) {
  var userId = req.params.userid;
  User.findById(userID, function (err, user) {
    console.log("USER JSON? :"+user.json());
    return res.send(user.json());
  });
});

models/user

var mongoose = require('mongoose');
var Schema = mongoose.Schema;
var mongooseUniqueValidator = require('mongoose-unique-validator');

var schema = new Schema({
    firstName: {type: String, required: true},
    lastName: {type: String, required: true},
    password: {type: String, required: true},
    email: {type: String, required: true, unique: true},
    polls: [{type: Schema.Types.ObjectId, ref: 'Poll'}],
    votes: [{
      poll: {type: Schema.Types.ObjectId, ref: 'Poll'},
      choice: {type: Number},
    }],
});

schema.plugin(mongooseUniqueValidator);

module.exports = mongoose.model('User', schema);

• javascript
• node.js
• mongodb
• angular
• typescript

Share Improve this question Follow edited May 28, 2017 at 20:09 Coder1000 asked May 21, 2017 at 10:29 Coder1000Coder1000 4,4911010 gold badges3737 silver badges8787 bronze badges 22

• usually this error is result of wrong formatted json that javascript trying to load through ajax request. for example: {'name':'shlomo'} instead of {"name":"shlomo"} – happyZZR1400 Commented May 21, 2017 at 10:31
• @happyZZR1400 Thanks for the insight ! But I really don't understand where or how my json could be incorrectly formatted :/ – Coder1000 Commented May 21, 2017 at 10:32
• I don't have to look any further than "Unexpected token <" to know that the response is getting HTML and not JSON. Note that < is the opening of a tag. Easily debugged by simply doing .do( response => console.log(response.text()) – Neil Lunn Commented May 21, 2017 at 10:32
• @NeilLunn I agree, I just don't see how or why that happens :/ I googled for a lot of time but could not find what was wrong in my code. There are already plenty of similar questions on SO but each have a different solution. – Coder1000 Commented May 21, 2017 at 10:33
• @Coder1000 you can check the Network tab of browser to see the response & verify which api is getting HTML response – Agam Banga Commented May 21, 2017 at 10:35

 |  Show 17 more ments

1 Answer 1

Sorted by: Reset to default 5

This error happens when server responds with HTML instead of JSON, particularly when a route is not found and the response is 404 page.

It's unlikely that API has the only route which is mounted at root and available as http://localhost:3000/'+userID, just because it's not possible for the server to do anything else in this case.

If the route is mounted to some path, like

app.use('/user', userRoutes);

then the requests should be performed to this path as well

return this.http.get('http://localhost:3000/user/'+userID)

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