[fix] Safari cors error

[guest363]

[client][parser] When you use in iframe on Safari vastClient can't get VAST. Request is block by CORS.

Description

• Migrate from xmlhttprequest to fetch. Fetch select between 2 modes: 'cors' : 'no-cors' depends on options.withCredentials
• To macros added support pattern %5B{key}%5D

Issue

Issue Link [Optional]

Type

• [ ] Breaking change
• [ ✔️ ] Enhancement
• [ ✔️ ] Fix
• [ ] Documentation
• [ ] Tooling

[ZacharieTFR]

Hello, Thanks for the contribution, but I think that using a custom urlHandler is more appropriate to your need. VASTClient's get method accepts a custom URLHandler as an optional parameter https://github.com/dailymotion/vast-client-js/blob/master/docs/api/vast-client.md#parameters-1

const customUrlHandler = {
  get(url, options, cb) {    
     // Add your fetch code with your CORS handling here 
  }
}
const vastClient = new VASTClient();
vastClient.get('http://example.dailymotion.com/vast.xml', options)
  .then(res => {
    // Do something with the parsed VAST response
  })
  .catch(err => {
    // Deal with the error
  });

Also I'm not sure to understand the need for %5B{key}%5D macro pattern.

[guest363]

Macro pattern %5B and %5D is for support [ and ] in url encode. That's actualy a not common case, but i faced this problem. Custom URLHandler is a good desigion, thats will fix my broblem, thanks.

[ZacharieTFR]

Got it 👍 I will close this PR, but feel free to open an issue if you face any other problem !