input validation via JMESpath in Angular 2

Question

So for example i have the following input:

<input type="text" name="field1" [(ngModel)]="rule['condition']">

in this input field is following input valid saleschannel.totalamount > 15. At the moment i test the validation with jmespath.search({ } , rule['condition']).

So i have following code part

<input type="text" name="field1" [(ngModel)]="rule['condition']"
[class.valid]="jmespath.search({ } , rule['condition'])">

The Problem with this is, if my input is not valid cause of syntax error i get an console error. So for the [class.invalid]="XXX" i need a way to catch the error, which detects for me that the input is invalid.

What can i do to achieve this or is there a better way than my attempt?

score 0 · Accepted Answer · answered Jun 27 '18 at 10:15

Got it working along time ago but forgot to answer on my own question.

component.html

<input type="text" (ngModelChange)="ValidateJMES($event)" [class.valid]="isValid">

component.ts

public jmespath = require('../../assets/jmespath.js');
public valid: bool;

ValidateJMES(newValue){
    try {
        this.jmespath.search({ } , newValue);
        valid = true;

    } catch(e) {
        valid = false;
    }
}

This way you can check if an input is a valid jmespath search expression.

input validation via JMESpath in Angular 2

1 Answers1