[PATCH] $request_scheme variable

[Chris Branch]

# HG changeset patch
# User Chris Branch <cbranch at cloudflare.com>
# Date 1488195909 0
#      Mon Feb 27 11:45:09 2017 +0000
# Node ID 05f555d65a33ebf005fedc569fb52eba3758e1d7
# Parent  87cf6ddb41c216876d13cffa5e637a61b159362c
$request_scheme variable.

Contains the URI scheme supplied by the client. If no scheme supplied,
equivalent to $scheme.

Scheme can be supplied by the client in two ways:

* HTTP/2 :scheme pseudo-header.
* HTTP/1 absolute URI in request line.

diff -r 87cf6ddb41c2 -r 05f555d65a33 src/http/ngx_http_variables.c
--- a/src/http/ngx_http_variables.c	Fri Feb 17 17:01:27 2017 +0300
+++ b/src/http/ngx_http_variables.c	Mon Feb 27 11:45:09 2017 +0000
@@ -105,6 +105,8 @@
     ngx_http_variable_value_t *v, uintptr_t data);
 static ngx_int_t ngx_http_variable_request_id(ngx_http_request_t *r,
     ngx_http_variable_value_t *v, uintptr_t data);
+static ngx_int_t ngx_http_variable_request_scheme(ngx_http_request_t *r,
+    ngx_http_variable_value_t *v, uintptr_t data);
 static ngx_int_t ngx_http_variable_status(ngx_http_request_t *r,
     ngx_http_variable_value_t *v, uintptr_t data);
 
@@ -288,6 +290,10 @@
       ngx_http_variable_request_id,
       0, 0, 0 },
 
+    { ngx_string("request_scheme"), NULL,
+      ngx_http_variable_request_scheme,
+      0, 0, 0 },
+
     { ngx_string("status"), NULL,
       ngx_http_variable_status, 0,
       NGX_HTTP_VAR_NOCACHEABLE, 0 },
@@ -2158,6 +2164,24 @@
 
 
 static ngx_int_t
+ngx_http_variable_request_scheme(ngx_http_request_t *r,
+    ngx_http_variable_value_t *v, uintptr_t data)
+{
+    if (r->schema_start) {
+        v->len = r->schema_end - r->schema_start;
+        v->valid = 1;
+        v->no_cacheable = 0;
+        v->not_found = 0;
+        v->data = r->schema_start;
+
+        return NGX_OK;
+    }
+
+    return ngx_http_variable_scheme(r, v, data);
+}
+
+
+static ngx_int_t
 ngx_http_variable_connection(ngx_http_request_t *r,
     ngx_http_variable_value_t *v, uintptr_t data)
 {