Comments Getting Added Twice

import { Component, Input } from '@angular/core';
import { Entry } from '../shared/entry.model';

@Component({
    selector: 'app-entry',
    templateUrl: 'entry.component.html',
    styleUrls: ['entry.component.css']
})

export class EntryComponent {
    @Input() entry: Entry;

    onCommentAdded(comment: {name: string; comment: string;}) {
        this.entry.comments.push(comment);
    }
}

import { Component, EventEmitter, Input, Output, ViewChild } from '@angular/core';
import { NgForm } from '@angular/forms';
import { EntryService } from '../shared/entry.service';

@Component({
    selector: 'app-entry-comment-form',
    templateUrl: 'entry-comment-form.component.html' 
})

export class EntryCommentFormComponent {
    name: string;
    comment: string;
    @Input() entryId: number;
    @Output() onCommentAdded = new EventEmitter<{name: string; comment: string;}>();
    @ViewChild('commentForm') commentForm: NgForm;

    constructor(private entryService: EntryService) {

    }

    onSubmit(commentForm: NgForm) {
        let comment = { name: this.name, comment: this.comment};
        this.entryService.addComment(this.entryId, comment)
        .then(() => {
            this.onCommentAdded.emit(comment);
            this.commentForm.resetForm();
        })
        this.onCommentAdded.emit(comment);
        this.commentForm.resetForm();
    }
}

import { Entry } from './entry.model';
import { Injectable } from '@angular/core';
import { Http } from '@angular/http';

@Injectable()
export class EntryService {

    constructor(private http: Http) {

    }

    addComment(entryId: number, comment: {name: string; comment: string;}) {
        return this.http.post(`app/entries/${entryId}/comments`, comment)
            .toPromise();
    }

    getEntries(): Promise<Entry[]> {
        return this.http.get('app/entries')
            .toPromise()
            .then(response => response.json().data as Entry[]);
    }
}