wp_redirect not working - php

Question

I am trying to post to a page and do some wordpress insertion in post but somehow the redirect is not working and after that. I tried following three options:
wp_redirect($location);
wp_safe_redirect($location);
header('Location:http://example.com');
here is what I want to do:
posting to another page.
look for file to be uploaded and upload directory
Upload the file.
Set post thumbnail using set_post_thumbnail
redirect to desired page.
the script work till setting thumbnail and then dies.
If anyone want to use it to upload thumbnail from template front end, they can use it.
// if you have this in a file you will need to load "wp-load.php" to get access to WP functions. If you post to "self" with this code then WordPress is by default loaded
require $_SERVER['DOCUMENT_ROOT'] . "/wp-load.php";
// require two files that are included in the wp-admin but not on the front end. These give you access to some special functions below.
require $_SERVER['DOCUMENT_ROOT'] . "/wp-admin/includes/file.php";
require $_SERVER['DOCUMENT_ROOT'] . "/wp-admin/includes/image.php";
// required for wp_handle_upload() to upload the file
$upload_overrides = array( 'test_form' => FALSE );
global $current_user;
get_currentuserinfo();
$logged_in_user = $current_user->ID;
//get user POST information
global $post;
$loop = new WP_Query( array(
'posts_per_page' => 1,
'post_type' => "vet-profile",
'order' => "ASC",
'orderby' => "menu_order",
'author'=>"$logged_in_user"
)
);
while ( $loop->have_posts() ): $loop->the_post();
$current_postID = $post->ID;
$current_posttitle = get_the_title();
endwhile;
// count how many files were uploaded
$upload_files = $_FILES[ 'upload_files' ];
// load up a variable with the upload direcotry
$uploads = wp_upload_dir();
// foreach file uploaded do the upload
//foreach ( range( 0, $count_files ) as $i )
//{
// create an array of the $_FILES for each file
$file_array = array(
'name' => $_FILES['upload_files']['name'],
'type' => $_FILES['upload_files']['type'],
'tmp_name' => $_FILES['upload_files']['tmp_name'],
'error' => $_FILES['upload_files']['error'],
'size' => $_FILES['upload_files']['size'],
);
// check to see if the file name is not empty
if ( !empty( $file_array['name'] ) )
{ ?>
<?php
// upload the file to the server
$uploaded_file = wp_handle_upload( $upload_files, $upload_overrides );
if ( $uploaded_file )
{
echo '<script>alert("Image successfully uploaded.\n");</script>';
}
else
{
echo '<script>alert("Fish! some error occured. Please try again.");</script>';
}
// checks the file type and stores in in a variable
$wp_filetype = wp_check_filetype( basename( $uploaded_file['file'] ), null );
// set up the array of arguments for "wp_insert_post();"
$attachment = array(
'post_mime_type' => $wp_filetype['type'],
'post_title' => preg_replace('/\.[^.]+$/', '', basename( $uploaded_file['file'] ) ),
'post_content' => '',
'post_author' => $logged_in_user,
'post_status' => 'inherit',
'post_type' => 'attachment',
'post_parent' => $current_postID,
'guid' => $uploads['url'] . '/' . $file_array['name']
);
// insert the attachment post type and get the ID
$attachment_id = wp_insert_attachment( $attachment, $uploaded_file['file'], $current_postID );
// generate the attachment metadata
$attach_data = wp_generate_attachment_metadata( $attachment_id, $uploaded_file['file'] );
// update the attachment metadata
wp_update_attachment_metadata( $attachment_id, $attach_data);
// set thumbnail to the current post
set_post_thumbnail( $current_postID, $attachment_id );
echo '<script>alert("set thumbnail")';
$location = empty($_POST['redirect_to']) ? get_redirect_link() : $_POST['redirect_to'];
wp_safe_redirect( $location );
echo '<script>alert("End Loop");</script>';
}
Thanks in Advance

Answer 1

I've found that the only place I can reliably call wp_redirect is in a callback function to the init action hook (http://codex.wordpress.org/Plugin_API/Action_Reference/init) as it clearly states in the documentation:
Runs after WordPress has finished loading but before any headers are
sent. Useful for intercepting $_GET or $_POST triggers.
You might want to look into this. The other thing you might want to try, if this doesn't work for you, is using output buffering. Here's a neat tutorial on how to do that:
http://tommcfarlin.com/wp_redirect-headers-already-sent/

Answer 2

echo '<script>alert("set thumbnail")';
$location = empty($_POST['redirect_to']) ? get_redirect_link() : $_POST['redirect_to'];
wp_safe_redirect( $location );
echo '<script>alert("End Loop");</script>';
The above code will most surely not work. You can't redirect after you've written something to the output. I didn't check the rest of the code, but if it works as you say, removing the top and bottom row (or just the top row even) should make it all work:
$location = empty($_POST['redirect_to']) ? get_redirect_link() : $_POST['redirect_to'];
wp_safe_redirect( $location );
(If you enable debug mode in wp-config.php you should see an error message instead of just a white screen. So if this doesn't work, you can copy the error over here and we can know exactly what the problem is.)