Forum Discussion

haamro's avatar
haamro
Visitor
11 years ago

AsyncPostFromSTring / GetString only getting 2 Character

Hello All, I am anewbie, in a process of making my first roku app which fetches data from another website after Logging in. I have attached all the necessary headers and using AsyncPostFromSTring to post the data. I am getting a msg.GetResponseHeadersr but with msg.GetString() it only revelas two character "< []" (small box).

I don't know what I am doing wrong. GetResponseHeader says "transfer-encoding: chunked" , is this where the issue is ?

this is my code

    loginURL="http://www.example.com/members/logmein.php"
    username="uname"
    password="pword"
    postContent="username="+username+"&password="+password
    
    
    request = CreateObject("roURLTransfer")
    xport=CreateObject("RoMessagePort")
    request.InitClientCertificates()
    request.SetCertificatesFile("common:/certs/ca-bundle.crt")
    request.setUrl(loginURL)
    request.SetMessagePort(xport)
    request.RetainBodyOnError(true)
    
     REM **** THIS headers works fine in PHP Curl ****
    request.AddHeader("Accept","text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,*/*;q=0.8")
    request.AddHeader("Accept-Encoding","gzip, deflate")
    request.AddHeader("Accept-Language","en-US,en;q=0.8,hi;q=0.6,ne;q=0.4")
    request.AddHeader("Cache-Control","max-age=0")
    request.AddHeader("Connection","keep-alive")
    request.AddHeader("Content-Type","application/x-www-form-urlencoded")
    request.AddHeader("Host","www.example.com")
    request.AddHeader("Origin","http://www.example.com")
    request.AddHeader("Referer","http://www.example.com/logmein.php")
    request.AddHeader("User-Agent","Mozilla/5.0 (Windows NT 6.3; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/40.0.2214.115 Safari/537.36")
    request.EnableCookies()
    
    
     if (request.asyncPostFromSTring(postContent))
    
     msg = wait(0,xport)

      if type(msg) = "roUrlEvent"
       Print "we are getting some input"
       Print msg.GetResponseHeaders()   ' This prints header
        print msg.GetString()                  ' this doesn't work
        
   
        end if

        
      end if


Any help is appreciated. Thank you
Roku Developer Program

8 Replies

  • RokuMarkn's avatar
    RokuMarkn
    Visitor
    11 years ago
    My first guess is your document contains non-ASCII characters (maybe a null?) that cause the print to fail. Try printing msg.GetString().Len() and see if it really contains two characters or if there are more that aren't getting printed.

    --Mark
  • haamro's avatar
    haamro
    Visitor
    11 years ago
    Thanx for the prompt reply,

    msg.GetString().Len() => 2 . So it is indeed two character

    I have a similar script written in PHP, which gets the entire content. So I know all headers/login process/request I am making are valid. The only thing I can think of is roku not handling "transfer-encoding: chunked".
  • belltown's avatar
    belltown
    Roku Guru
    11 years ago
    At the very least you should check your HTTP response code:

    print "Response Code: "; msg.GetResponseCode ()


    after your roUrlEvent completes.
  • haamro's avatar
    haamro
    Visitor
    11 years ago
    "belltown" wrote:
    At the very least you should check your HTTP response code:

    print "Response Code: "; msg.GetResponseCode ()


    after your roUrlEvent completes.
    it is 200
  • haamro's avatar
    haamro
    Visitor
    11 years ago
    looks like roku cannot handle "gzip"

    changed to

       request.AddHeader("Accept-Encoding","deflate")

    Its working now 🙂
  • belltown's avatar
    belltown
    Roku Guru
    11 years ago
    "haamro" wrote:
    looks like roku cannot handle "gzip"

    It can handle gzip encoding, but you have to tell it to do so:


    request.EnableEncodings (True)
  • haamro's avatar
    haamro
    Visitor
    11 years ago
    Thanx. Encoding enabled.

    I am getting the entire body but I didn't realized that my form with username and password was not posted. It didn't log me in. Any thoughts ? Also, is there any examples on working with Cookies ?

    Once logged in, I need a session / Cookie to fetch multiple files. I couldn't find proper way of dealing with cookies. If the Cookies are enabled, do I need to call them while fetching the next file ?
  • belltown's avatar
    belltown
    Roku Guru
    11 years ago
    I'm not quite sure why your form wasn't posted.

    One thing to note, however, is that you should be Url-Encoding your form fields if you're submitting it with a Content Type of "application/x-www-form-urlencoded":


    ut = CreateObject ("roUrlTransfer")
    postContent = "username=" + ut.Escape (username) + "&password= " + ut.Escape (password)


    Also, you have a lot of AddHeader statements, not all of which are necessary, as the Roku will provide many of the headers itself. I do know that it's safe to change the User-Agent header, but I'd try leaving out the others unless you find a compelling reason to include any of them.

    As far as the cookies are concerned, in most of the work I did with cookies I handled them manually. I didn't use EnableCookies, etc. because I wanted my code to run on the older 3.1 firmware. I would assume though that if you use EnableCookies then the "cookie cache" should be able to handle sending the Cookies back to the server, although I can't confirm that.

    Another issue with logging in with a username and password is the authentication mechanism used by the server. I've not come across many servers that send plain text usernames/passwords over an unencrypted Http connection. Even many servers that use encrypted Http will use some form of authentication (Basic, Digest, etc.) You should make sure that you are using the same form of authentication that your server requires.