add PHP server prepend file as codespaces uses HTTP_X_FORWARDED_X

Author: jordikroon

.devcontainer/build.sh

@@ -25,9 +25,12 @@ php -d memory_limit=512M ../phd/render.php \
 # Restart any existing server, then launch the new one in its own session so
 # Ctrl+C in the debug terminal only kills the log tail below. The server keeps
 # running until the next build replaces it (or the container shuts down).
+#
+# auto_prepend_file rewrites $_SERVER from the request's Host header so the PHP
+# format's $MYSITE-built URLs work behind Codespaces / other port forwarders.
 LOG="/tmp/php-server-${FORMAT}.log"
 pkill -f 'php -S 0.0.0.0:8080' 2>/dev/null || true
-setsid nohup php -S 0.0.0.0:8080 -t "$DOCROOT" \
+setsid nohup php -d "auto_prepend_file=$PREPEND" -S 0.0.0.0:8080 -t "$DOCROOT" \
     >"$LOG" 2>&1 </dev/null &
 SERVER_PID=$!
 

.devcontainer/server-prepend.php

@@ -0,0 +1,15 @@
+<?php
+
+// This file rewrites $_SERVER from the request's Host header so the PHP
+// format's $MYSITE-built URLs work behind Codespaces / other port forwarders.
+
+$forwardedHttps = ($_SERVER['HTTP_X_FORWARDED_PROTO'] ?? '') === 'https';
+$hostHeader = $_SERVER['HTTP_X_FORWARDED_HOST'] ?? $_SERVER['HTTP_HOST'] ?? '';
+
+if ($hostHeader !== '') {
+    $_SERVER['HTTP_HOST'] = $hostHeader;
+}
+
+if ($forwardedHttps) {
+    $_SERVER['HTTPS'] = 'on';
+}