From c6ea47c0208747926edb8adaf9f5ff30c38fa21b Mon Sep 17 00:00:00 2001
From: Even Rouault <even.rouault@spatialys.com>
Date: Mon, 9 Dec 2024 17:16:53 +0100
Subject: [PATCH] Document MS_WMS_ERROR_STATUS_CODE

added in https://github.com/MapServer/MapServer/pull/7191
---
 en/mapfile/config.txt |  1 +
 en/ogc/wms_server.txt | 31 +++++++++++++++++++++++++++++++
 2 files changed, 32 insertions(+)

diff --git a/en/mapfile/config.txt b/en/mapfile/config.txt
index 7e2092f1646..f851ccc9edd 100644
--- a/en/mapfile/config.txt
+++ b/en/mapfile/config.txt
@@ -154,6 +154,7 @@ A full sample config file is shown below:
       # MS_OPENLAYERS_JS_URL "http://openlayers.org/api/OpenLayers.js"
       # MS_TEMPPATH "/tmp"
       # MS_MAX_OPEN_FILES 200 # maximum number of open files allowed on Windows
+      # MS_WMS_ERROR_STATUS_CODE "ON"  # enable HTTP status code 4xx and 5xx in case of errors on WMS requests
     END
 
     #
diff --git a/en/ogc/wms_server.txt b/en/ogc/wms_server.txt
index a9095373710..20967758377 100644
--- a/en/ogc/wms_server.txt
+++ b/en/ogc/wms_server.txt
@@ -2165,6 +2165,37 @@ Vendor specific WMS parameters
 .. index::
    pair: WMS; Cascading requests
 
+HTTP status error codes
+-----------------------
+
+The OGC WMS specification is not explicit about which HTTP status error code
+servers should return in case of errors. Traditionaly most WMS implementation
+return "200 OK" in those situations. Starting with MapServer 8.4, it is
+possible to define the ``MS_WMS_ERROR_STATUS_CODE`` configuration option to ``ON``
+in the CONFIG.ENV section of the MapServer configuration file to ask MapServer
+to return HTTP 4xx or 5xx status codes in case of error.
+
+
+.. code-block:: mapfile
+
+
+  CONFIG
+    #
+    # Environment variables
+    #
+    ENV
+      #
+      # Limit Mapfile Access
+      #
+      # MS_MAP_NO_PATH "1"
+      MS_MAP_PATTERN "^/opt/mapserver" ## required when referencing mapfiles by path
+      # MS_MAP_BAD_PATTERN "[/\\]{2}|[/\\]?\\.+[/\\]|,"
+
+      # Enable HTTP status code 4xx and 5xx in case of errors on WMS requests
+      MS_WMS_ERROR_STATUS_CODE "ON"
+    END
+  END
+
 Cascading WMS Requests
 ----------------------