drush script to export content from a Drupal book module: http://drupal.org/documentation/modules/book

drupal-book-module-export.php

<?php

$outdir = '/home/pdurbin/drupal/exported';
$old_base_url = 'http://www.example.com';
$limit_post_count_for_testing = 0;
$post_limit = 20;

$formats["4"] = 'txtl';

#$nid = 7; // About
$nid = 88; // Internal Documentation
$node = node_load($nid);
# handy for checking which books are visible to drush
#$books = book_get_books();
#print_r($books);
$tree = book_menu_subtree_data($node->book);
$it = new RecursiveIteratorIterator(new RecursiveArrayIterator($tree));
$count = 0;
foreach ($it as $el) {
        $depth = $it->getDepth();
        $half = $depth / 2;

        #print_r($el);

        $key = $it->key();
        $mod = $depth % 2;
        if ($mod == 1)  {
            continue;
        }
        $indent = str_repeat('-', $half);
        if ($key != 'nid') {
            continue;
        }
        $mynode = node_load($el);


        $title = $mynode->title;
        $title = str_replace(':', '-', $title);
        # for... title: "Static" site
        $title = str_replace('"', '', $title);
        # for... title: *Expense Code Editing (for lab admins)
        $title = str_replace('*', '', $title);
        $body = $mynode->body;
        $nid = $mynode->nid;
        $format = $mynode->format;
        $created = $mynode->created;
        $changed = $mynode->changed;
        $author = $mynode->name;
        $old_url_path = $mynode->path;
        $drupal_info = "\n----\n\nThis page was imported from Drupal, where it was known as:\n\n";
        if ($old_url_path) {
            $drupal_info .= "* $old_base_url/$old_url_path\n";
        }
        $drupal_info .= "* $old_base_url/node/$nid\n";
        $drupal_info .= "* created: " . date("Y-m-d", $created) . "\n";
        $drupal_info .= "* changed: " . date("Y-m-d", $changed) . " by $author\n";
        #print "$drupal_info\n";

        #if ($nid != 90) {
        #if ($nid != 132) {
        #    continue;
        #}

        $files = $mynode->files;
        #print_r($files);
        if ($files) {
           $drupal_info .= "\nThis page had attached files (". count($files) . " of them):\n\n";
        }
        $filecount = 1;
        foreach ($files as $file) {
            #print_r($file);
            $drupal_info .= "File $filecount:\n\n";
            #[filepath] => sites/default/files/Proteomics_project_ProteomeDiscoverer_risks_1.xls
            $filepath = $file->filepath;
            $drupal_info .= "* former url: $old_base_url/$filepath\n";

            #[filemime] => application/vnd.ms-excel
            $filemime = $file->filemime;
            $drupal_info .= "* type: $filemime\n";

            #[timestamp] => 1271783235
            $filetime = $file->timestamp;
            $drupal_info .= "* uploaded: " . date("Y-m-d", $filetime) . "\n";
            $drupal_info .= "* saved to: /redacted/drupal_old_internal/snapshots/2012-03-07/rc/$filepath\n";
            $drupal_info .= "\n";


            #[status] => 1
            #[filename] => Proteomics_project_ProteomeDiscoverer_risks.xls
            #[description] => Proteomics_project_ProteomeDiscoverer_risks.xls
            $filecount++;

        }

        #if ($nid == 646) {
        #    print_r($mynode);
        #}

        if ($limit_post_count_for_testing) {
            #print_r($mynode);
            if ($count > $post_limit ) {
                break;
            }
            $count++;
        }

        $dir;

        $dir[$half] = $nid;
        $path = '';
        for ($i = 1; $i <= $half; $i++) {
            $path .= "/$dir[$i]";
        }
        printf("%-23s %s ($format)\n", $path, $title);
        #print_r($dir);
        system("mkdir -p $outdir/$path", $retval);
        if ($retval !== 0) {
            print "ERROR! couldn't mkdir $outdir/$path\n";
            break;
        }

        $title = preg_replace('/\r/', '', $title);
        $body = preg_replace('/\r/', '', $body);

        $content = "[[!meta title=\"$title\"]]\n\n$body\n$drupal_info";
        $ext = 'mdwn';
        if ($format == 4) {
            $ext = $formats["4"];
        }

        $file = "$outdir/$path.$ext";
        print "$file\n";
        $fh = fopen($file, 'w') or die("can't open $file");
        fwrite($fh, $content);
        fclose($fh);
}