await page.fill('input[name=title]', 'Title');
        await page.fill('input[name=author]', 'Author');

        const [request] = await Promise.all([
            page.waitForRequest(request => request.method() === 'POST'),
            page.click('text=Submit'),
        ]);
        const data = JSON.parse(request.postData());

        expect(data.title).to.be.equal('Title');
        expect(data.author).to.be.equal('Author');