Puppeteer page.evaluate querySelectorAll return empty objects

Question

I am trying out Puppeteer. This is a sample code that you can run on: https://try-puppeteer.appspot.com/

The problem is this code is returning an array of empty obje

Answer 1

The values returned from evaluate function should be json serializeable. https://github.com/GoogleChrome/puppeteer/issues/303#issuecomment-322919968

the solution is to extract the href values from the elements and return it.

 await this.page.evaluate((sel) => {
        let elements = Array.from(document.querySelectorAll(sel));
        let links = elements.map(element => {
            return element.href
        })
        return links;
    }, sel);