Hello,

I get this error in the reports-log:

Location: http://xxx/boost-crawler?nocache=1&key=419bd7c94e292f4a5a499d36ca2dd1eb&...
Message: Cannot modify header information - headers already sent by (output started at /xxx/sites/all/modules/boost/boost.module:4238) in /usr/share/phpbb3/www/includes/session.php on line 1007.

This error is thrown by the cron_crawler, not for normal page views. I have installed the module "phpBBforum Integration module", which integrates the forum directly in the site. It seems to be a compatibility issue. It seems to be similar to the issue #657960: Cannot modify header information - headers already sent .

When I call the URL as in the error message, the header is written by boost with the output "async". After that the phpbb module tries to write another header and the error is thrown. The phpbb module sets another cookie and writes an own header using the header() function from php. I already exluded the phpbbforum pages from the boost caching, but the blocks from the ppbb module are in every page.

How can this problem be solved or the error prevented?

Comments

mikeytown2’s picture

try the latest dev version of boost

florians’s picture

I tried it, but the message still appears. The message changed to:

http://xxx/boost-crawler?nocache=1&key=419bd7c94e292f4a5a499d36ca2dd1eb&thread=1&total=-350&expire=0
Cannot modify header information - headers already sent by (output started at /xxx/sites/all/modules/boost/boost.module:5352) in /usr/share/phpbb3/www/includes/session.php on line 1007.

Do you have an idea, what the problem might be?

mikeytown2’s picture

I see the source of the error... try disabling this setting under Boost advanced settings
"Asynchronous Operation: output HTML, close connection, then store static file."

florians’s picture

Thank you for the hint. I deactivated the function, but the message still appears. So it does not change the error. I think the phpbb3 module also modifies the header, which creates this conflict. Is there another way, how I can circumvent this error or solve this problem? Thx.

mikeytown2’s picture

Does it still say (output started at /xxx/sites/all/modules/boost/boost.module:5352)?

florians’s picture

You're right, the line changed. Now I get this message:

Cannot modify header information - headers already sent by (output started at /.../sites/all/modules/boost/boost.module:5399) in /usr/share/phpbb3/www/includes/session.php on line 1007.
mikeytown2’s picture

It appears that the crawler is not compatible with phpBBforum. In order for the crawler to work it has to send out its own headers.

florians’s picture

ok. Can I prevent somehow the crawler from crawling the pages with the phpbbforum? I already excluded the sites from the boost cache, however the crawler still requests these pages.

mikeytown2’s picture

it's the crawler url that is the issue. for some reason phpbbforum is wanting to intercept the calls the crawler makes to its self.

florians’s picture

Why is the crawler calling itsself? I hope you can give me a short answer or a hint, where I can find this information to understand the functionality of the crawler.

When I understand it right, the phpbbforum module has to ignore the calls to the crawler and then everything should work? Then I can have a look to the phpbb module to solve the problem.

Thank you.

mikeytown2’s picture

Crawler hits its self to get around restrictions setup by shared hosts for php runtime and so it can be multi-threaded. It's the best way to accomplish these two goals and have it work on all hosts across 4.x and 5.x php running on any environment.

So yes ignore that URL /boost-crawler and everything should work

florians’s picture

Thank you very much for the information and the fast replies! I'll have a look at the phpbb module to check its compatibility to boost.

mrfelton’s picture

I have the same issue, and I don't have phpbbforum installed.

After updating to the latest boost from CVS, my error has changes to the following:

http://www.example.com/boost-crawler?nocache=1&key=ffe0834d5031c60794733ee1a9a5ffdb&thread=1&total=1&expire=

Warning: session_start() [<a href='function.session-start'>function.session-start</a>]: Cannot send session cache limiter - headers already sent (output started at /var/aegir/platforms/msf/msf-build-dev-2010101601/profiles/msf/modules/contrib/boost/boost.module:5629) in drupal_session_start() (line 1734 of /var/aegir/platforms/msf/msf-build-dev-2010101601/includes/bootstrap.in
chingis’s picture

I have the same problem, turning off "Asynchronous Operation: output HTML, close connection, then store static file." option didn't help.

Location:
/boost_views.php?new_nodes[344794]=344794&rand=1710176642&key=c705c5f1ee8c7dc543f1450e371abb5c

Warning: session_start() [function.session-start]: Cannot send session cache limiter - headers already sent (output started at /boost/boost.module:6055) in drupal_session_start() (line 1745 of /includes/bootstrap.inc).