Where does WP write headers?

  • justpetehere

    (@justpetehere)


    19 years, 11 months ago

    Hey all,

    I’m trying to figure out the best place to put the following piece of code, or how to best modify it:

    if (is_404()) {
    if (file_exists('/home/justpete/archive' . $_SERVER[REQUEST_URI])) {
    header("HTTP/1.1 301 Moved Permanently");
    header("Location: http://archive.justpetehere.com" . $_SERVER[REQUEST_URI]);
    exit();
    }
    }

    I just replaced my previous blog with WP, and decided to not import it, rather, just move it over to an “archive” hostname on the same server. This script checks if the file requested exists on the archive hostname, and if so, sends a 301 to redirect. I also want to have it check if somehow the page ALSO exists on the WP blog, so the if is_404 would be nice.

    The problem is that I can’t figure out a place in the calls before PHP defines the header for the document.

    Anyway, any ideas?

Viewing 3 replies - 1 through 3 (of 3 total)
  • Moderator Samuel Wood (Otto)

    (@otto42)

    WordPress.org Admin

    19 years, 11 months ago

    Headers are not sent until some other actual text is sent. So even though the header has been “set” as it were, you can still override it as long as no actual output has been done yet.

    Best way to do that that I can think of is to make a 404.php in your theme directory. This gets called when wordpress has a 404 error page to display.

    Thread Starter justpetehere

    (@justpetehere)

    19 years, 11 months ago

    Otto,

    Unfrotunately that’s not working. I tried just placing the header lines without the if statements in the index.php of my template with the end();. I just end up with a blank page. And I’m assuming that it does define the content-type header at some point, as there are functions specifically for the purpose.

    Any other ideas?

    geoffe

    (@geoffe)

    19 years, 11 months ago

    Not all requests for files would be going through the index.php file in your template folder. They won’t necessarily be going through a header.php template either.

    Unfortunately, making your redirect in the 404.php template file of your theme won’t be much help because it has already sent the 404 header and you want it to get a 301.

    You’ll need to get into the WP_Rewrite workings and take a look at the parse_query function and perhaps the rewrite_rules function in wp-includes/classes.php to do some root_rewrite_rules filter to get the effect you want.

    However, I’d warn that what you want to do is potentially terribly inefficient for your server.

    Edit: look into doing your function through the handle_404() in the WP object at the bottom of classes.php

Viewing 3 replies - 1 through 3 (of 3 total)

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