How do I log in to an external website using Google Apps scripts?

Question

I'm trying to log in to a website so that I can drop data into a Google Docs table. I read various posts here, but I cannot figure out how to identify the data that I need to transfer.

The site login page has a form with the following fields.

<form action="https://fantasyfootball.telegraph.co.uk/premierleague/log-in/" method="post" id='reg-form'>
        <fieldset class='login'>

            <div class="required">
                <label for="email">Email:</label>
                <input type="text" name="email" id="email" class="input-text" size="10" maxlength="50" value="[e-mail]" />
            </div>

            <div class="required">
                <label for="pass">Password:</label>
                <input type="password" name="pass" id="pass" class="input-password" size="10" maxlength="15" value="some-password" />
            </div>
        </fieldset>
        <div id="remember-me-container">
                <input type="checkbox" checked="checked" id="remember-me" name="remember-me" value="remember-me" />
                <label for="remember-me" id="remember-lbl">Remember me</label>

        </div>

        <input type="submit" id="submit-btn" value="Login" name='Submit' class='btn'/>
    </form>

I tried the following script, but sessionDetails always returns as "Undefined."

// Returns the html of the page.
function sGetPage (sUrl) {

var url = "https://fantasyfootball.telegraph.co.uk/premierleague/log-in/";

// logging in, following http://stackoverflow.com/questions/21621019/google-apps-script-login-to-website-with-http-request
var payload =
{
 "email" : "[e-mail]",
 "pass" : "asdf123",
 "submit-btn": "Login",
 "remember-me" : "remember-me" 
};

var options =
{
 "method" : "post",
 "payload" : payload,
 "followRedirects" : false
};

var login = UrlFetchApp.fetch( url, options);
var sessionDetails = login.getAllHeaders()['Set-Cookie'];
Logger.log(sessionDetails); 

var response = UrlFetchApp.fetch ("https://fantasyfootball.telegraph.co.uk/premierleague/leagues/view/8000912/4015677/", {"headers" : {"Cookie" : sessionDetails} });
var sHtml = response.getContentText();
Logger.log(sHtml); 

}

Any advice would be appreciated.

Answer 1

sessionDetails . RegEx sessionDetails cookie . , cookie , ( ), , cookie , sessionDetails. .

var login = UrlFetchApp.fetch(url, options);
var sessionDetails = login.getAllHeaders()['Set-Cookie'];
Logger.log(sessionDetails); 
var cookie = sessionDetails.match(/Asp\.NetSessionId=[A-Z0-9]+;/)[0];  //modify this RegEx as needed

var response = UrlFetchApp.fetch(
  "https://example.com",
  {"headers" : {"Cookie" : cookie} }
);