Headers already sent error in CakePHP app

Question

            function new_photo()
            {

                if( !empty($this->data))
                {
                        $this->data['Photo']['showcase_id'] = $this->Session->read('CurrShowcase.id');
                        $this->data['Photo']['added'] = date("Y-m-d H:i:s");
                        $this->Showcase->Photo->save($this->data);

                        $flasher = 'Photo uploaded successfully';
                        $flasher .= '<br/><img src="' . $this->data['Photo']['thumbnail_url'] . '"/>';
                        $this->Session->setFlash($flasher);
                        //$this->redirect(array('action'=>'sc',));
                }
            }

I have a Showcase Controller in my CakePHP app, and a new photo form to submit new photos. Whenever I uncomment the last line that redirects after the data is saved, I get this error:

Warning (2): Cannot modify header information - headers already
sent by (output started at D:\.....

Even if I get this error, $this->data still gets saved properly in the database. However, if I comment the redirect line as shown above, everything works fine and error-free. I HAVE checked for blank spaces around the tags, so I'm pretty sure it's not that.

Any ideas?

Edit: commenting out the setFlash statement does not fix the problem.

Have you tried to redirect to another action? Why would you not remove the comma after 'sc'? — bancer, Jun 21 '10 at 23:19
The comma was one of the problems. I actually had a print_r($this->Session->read('CurrUser.username')); print_r($this->Session->read('CurrShowcase.id')); before the if statement which caused some issues. — vette982, Jun 23 '10 at 04:00

score 3 · Accepted Answer · answered Jun 25 '10 at 12:57

Change your debug mode to 0 to make sure it's not a notice/warning being generated prior to the redirect. Also, you might want to tighten up your processing section to (be paranoid and) ensure that it's not using invalid indexes, as well as anywhere else throughout the application flow for that action to make sure you're not getting any ouput (if it works when you change debug to 0).

score 1 · Answer 2 · answered Jun 21 '10 at 10:05

1

Is there a debug statement somewhere that you're not showing us?

answered Jun 21 '10 at 10:05

Leo

6,553
2
29
48

score 1 · Answer 3 · edited May 23 '17 at 11:46

1

You may be up against an invisible UTF-8 BOM character somewhere. Check your text editor settings whether it saves your files with BOM or without.

edited May 23 '17 at 11:46

Community

1
1

answered Jun 22 '10 at 01:22

deceze

510,633
85
743
889

score 1 · Answer 4 · answered Aug 05 '10 at 16:13

1

I'd check for whitespace in the models. Anyone of them. That was one of the gotchas I hit.

answered Aug 05 '10 at 16:13

Nigel

1,695
1
13
22

Matt Mitchell · Answer 5 · 2010-06-21T04:17:58.367

0

I'm assuming setFlash outputs something to the browser?

If whitespace before or after your <?php ?> tags isn't your issue you might have to try passing 'null' for the 'layout' parameter of setFlash();

i.e.

$this->Session->setFlash($flasher, null);

edited Jun 21 '10 at 04:17

answered Jun 21 '10 at 01:03

Matt Mitchell

40,943
35
118
185

Yes it just flashes a message (in this case, $flasher) on the next page loaded – vette982 Jun 21 '10 at 01:29
If you comment out setFlash and then redirect does it work? – Matt Mitchell Jun 21 '10 at 04:12
Answer updated with a possible solution. – Matt Mitchell Jun 21 '10 at 04:18
If I comment out setFlash it still does the same thing. – vette982 Jun 21 '10 at 21:08
Then it's probably outside the code we can see. Either you have an invisible character (try copying the code within your PHP tags into a new file with new php tags and using a new text editor) or you are calling another function that is sending either text or a header. – Matt Mitchell Jun 22 '10 at 04:10
Actually it tells you what file is sending the output anyway right? Is it the same file? – Matt Mitchell Jun 22 '10 at 04:10

score 0 · Answer 6 · answered Jun 21 '10 at 01:10

0

Either this code outputs something to the browser, or you have a whitespace after ?> in the end of the file (or any other included file). The whitespace is sent to the user thus sending http header.

answered Jun 21 '10 at 01:10

cypher

6,822
4
31
48

Headers already sent error in CakePHP app

6 Answers6