commit a3f3b143f4fe5221158125be67ba5e877653e525
Author: hladu357 <ondrej.hladuvka@gmail.com>
Date:   Wed May 15 13:41:57 2024 +0200

    compilable

diff --git a/config b/config
new file mode 100644
index 0000000..13da777
--- /dev/null
+++ b/config
@@ -0,0 +1,7 @@
+ngx_module_type=HTTP_AUX_FILTER
+ngx_module_name=ngx_http_key_header_module
+ngx_module_srcs="$ngx_addon_dir/http_key_header_module.c"
+
+. auto/module
+
+ngx_addon_name=$ngx_module_name
\ No newline at end of file
diff --git a/http_key_header_module.c b/http_key_header_module.c
new file mode 100644
index 0000000..b03cf75
--- /dev/null
+++ b/http_key_header_module.c
@@ -0,0 +1,108 @@
+#include <ngx_config.h>
+#include <ngx_core.h>
+#include <ngx_http.h>
+
+
+static ngx_http_output_header_filter_pt  ngx_http_next_header_filter;
+
+static ngx_int_t ngx_http_key_header_filter(ngx_http_request_t*);
+
+static ngx_int_t ngx_http_key_header_init(ngx_conf_t*);
+static void* ngx_http_key_header_create_conf(ngx_conf_t*);
+static char* ngx_http_key_header_merge_loc_conf(ngx_conf_t*, void* parent, void* child);
+
+typedef struct
+{
+    ngx_flag_t enabled;
+}
+ngx_http_key_header_loc_conf_t; 
+
+
+
+static ngx_command_t
+ngx_http_key_header_filter_commands[] =
+{
+   {
+     ngx_string("send_cache_key"),
+     NGX_HTTP_MAIN_CONF | NGX_HTTP_SRV_CONF | NGX_HTTP_LOC_CONF | NGX_CONF_FLAG, 
+     ngx_conf_set_flag_slot,
+     NGX_HTTP_LOC_CONF_OFFSET, 
+     offsetof(ngx_http_key_header_loc_conf_t, enabled),
+     NULL
+   },
+      
+   ngx_null_command
+};
+
+
+
+static ngx_http_module_t 
+ngx_http_key_header_filter_module_ctx =
+{
+    NULL,                              /* Pre config */
+    ngx_http_key_header_init,          /* Post config */
+    NULL,                              /* Create main config */
+    NULL,                              /* Init main config */
+    NULL,                              /* Create server config */
+    NULL,                              /* Merge server config */
+    ngx_http_key_header_create_conf,   /* Create loc config */
+    ngx_http_key_header_merge_loc_conf /* Merge loc config */
+};
+
+
+
+static ngx_int_t
+ngx_http_key_header_init(ngx_conf_t*)
+{
+    ngx_http_next_header_filter = ngx_http_top_header_filter;
+    ngx_http_top_header_filter = ngx_http_key_header_filter;
+    return NGX_OK;
+}
+
+
+static void*
+ngx_http_key_header_create_conf(ngx_conf_t *cf) 
+{
+    ngx_http_key_header_loc_conf_t *conf;
+    conf = ngx_pcalloc(cf->pool, sizeof(ngx_http_key_header_loc_conf_t));
+    if(conf == NULL) {
+        return NGX_CONF_ERROR;
+    }
+
+    conf->enabled = NGX_CONF_UNSET;
+    return conf;
+}
+
+
+static char*
+ngx_http_key_header_merge_loc_conf(ngx_conf_t *cf, void *parent, void *child) 
+{
+    ngx_http_key_header_loc_conf_t *prev = parent;
+    ngx_http_key_header_loc_conf_t *conf = child;
+
+    ngx_conf_merge_value(conf->enabled, prev->enabled, 0);
+
+    return NGX_CONF_OK;
+}
+
+ngx_module_t ngx_http_key_header_module =
+{
+    NGX_MODULE_V1,
+    &ngx_http_key_header_filter_module_ctx,     /* module context */
+    ngx_http_key_header_filter_commands,        /* module directives */
+    NGX_HTTP_MODULE,                            /* module type */
+    NULL,
+    NULL,
+    NULL,
+    NULL,
+    NULL,
+    NULL,
+    NULL,
+    NGX_MODULE_V1_PADDING
+};
+
+static ngx_int_t
+ngx_http_key_header_filter(ngx_http_request_t *r )
+{
+    return ngx_http_next_header_filter(r);   
+}
\ No newline at end of file