Asymmetrik/mean2-starter

import { Component } from '@angular/core';
import { Response } from '@angular/http';

import { BsModalRef } from 'ngx-bootstrap';

import { AdminService } from '../admin.service';

@Component({
    templateUrl: 'export-users.component.html'
})
export class ExportUsersModal {

    selectedField = 'username';

    delimiter = '; ';

    value = '';

    query = '{}';

    queryValid = true;

    private valuesArray: string[] = [];

    constructor(
        private adminService: AdminService,
        public modalRef: BsModalRef
    ) {}

    static isJsonString(str: string): boolean {
        try {
            JSON.parse(str);
        } catch (e) {
            return false;
        }
        return true;
    }

    ngOnInit() {
        this.retrieveUsers();
    }

    retrieveUsers() {
        if (null != this.selectedField && this.queryValid) {
            this.adminService.getAll(JSON.parse(this.query), this.selectedField)
                .subscribe((users: string[]) => {
                    this.valuesArray = users;
                    this.updateValue();
                }, (response: Response) => {
                    if (response.status >= 400 && response.status < 500) {
                        this.value = 'Unable to retrieve field values: ' + response.json().message;
                    }
                });
        }
    }

    updateQuery() {
        this.queryValid = ExportUsersModal.isJsonString(this.query);
        if (this.queryValid) {
            this.retrieveUsers();
        }
    }

    updateValue() {
        this.value = this.valuesArray.join(this.delimiter || ';');
    }
}