implemented nobackup upstream singlets

.github/workflows/ci.yml

@@ -9,7 +9,7 @@ jobs:
     continue-on-error: ${{ matrix.experimental }}
     strategy:
       matrix:
-        nginx: [1.16.1, 1.18.0, 1.20.2, 1.22.1]
+        nginx: [1.16.1, 1.18.0, 1.20.2, 1.22.1, 1.24.0]
         experimental: [false]
         include:
           - nginx: head

README.md

@@ -51,7 +51,9 @@ adjust their names. The 1st parameter is a suffix added after the name of the
 host upstream and before the ordering number. The 2nd parameter must be an
 integer value which defines *zero-alignment* of the ordering number, for example
 if it has value 2 then the ordering numbers could be
-``'01', '02', ..., '10', ... '100' ...``
+``'01', '02', ..., '10', ... '100' ...``. There is another optional parameter
+*nobackup* which marks secondary servers as down rather than backup. This
+parameter must be put after all other parameters.
 
 ### An example
 

nginx.conf

@@ -35,6 +35,11 @@ http {
         combine_server_singlets byname;
         combine_server_singlets _tmp_ 2;
     }
+    upstream u4 {
+        server localhost:8020;
+        server localhost:8030;
+        combine_server_singlets _single_ nobackup;
+    }
 
     upstream u01 {
         # to test next_upstream_statuses error set port 8140
@@ -67,6 +72,12 @@ http {
         next_upstream_statuses 5xx;
         intercept_statuses 5xx /Internal/failover;
     }
+    upstrand us4 {
+        upstream ~^u4_single_ blacklist_interval=60s;
+        order per_request;
+        next_upstream_statuses 5xx;
+        intercept_statuses 5xx /Internal/failover;
+    }
 
     proxy_read_timeout 5s;
     proxy_intercept_errors on;
@@ -106,6 +117,9 @@ http {
             proxy_buffering off;
             proxy_pass http://$upstrand_us2;
         }
+        location /us4 {
+            proxy_pass http://$upstrand_us4;
+        }
         location /echo/us1 {
             echo $upstrand_us1;
         }

src/ngx_http_combined_upstreams_module.c

@@ -50,7 +50,7 @@ static ngx_command_t  ngx_http_combined_upstreams_commands[] = {
       0,
       NULL },
     { ngx_string("combine_server_singlets"),
-      NGX_HTTP_UPS_CONF|NGX_CONF_NOARGS|NGX_CONF_TAKE12,
+      NGX_HTTP_UPS_CONF|NGX_CONF_NOARGS|NGX_CONF_TAKE123,
       ngx_http_combine_server_singlets,
       0,
       0,
@@ -325,7 +325,7 @@ ngx_http_combine_server_singlets(ngx_conf_t *cf, ngx_command_t *cmd, void *conf)
     u_char                         *fbuf;
     const char                     *fmt = "%V%d";
     ngx_uint_t                      flen;
-    ngx_uint_t                      byname = 0;
+    ngx_uint_t                      byname = 0, nobackup = 0;
 
     uscf = ngx_http_conf_get_module_srv_conf(cf, ngx_http_upstream_module);
     if (uscf->servers == NULL) {
@@ -337,6 +337,19 @@ ngx_http_combine_server_singlets(ngx_conf_t *cf, ngx_command_t *cmd, void *conf)
     value = cf->args->elts;
 
     if (cf->args->nelts > 1) {
+        if (value[cf->args->nelts - 1].len == 8
+            && ngx_strncmp(value[cf->args->nelts - 1].data, "nobackup", 8) == 0)
+        {
+            nobackup = 1;
+        }
+    }
+
+    if (cf->args->nelts > 3 && nobackup == 0) {
+        ngx_conf_log_error(NGX_LOG_EMERG, cf, 0, "invalid parameters");
+        return NGX_CONF_ERROR;
+    }
+
+    if (cf->args->nelts > 1 + nobackup) {
         suf = value[1];
 
 #if nginx_version >= 1007002
@@ -348,10 +361,10 @@ ngx_http_combine_server_singlets(ngx_conf_t *cf, ngx_command_t *cmd, void *conf)
         }
 #endif
 
-        if (cf->args->nelts > 2) {
+        if (cf->args->nelts > 2 + nobackup) {
             if (byname > 0) {
                 ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
-                                   "second parameter is not permitted when "
+                                   "setting field width is not permitted when "
                                    "using \"byname\" value");
                 return NGX_CONF_ERROR;
             }
@@ -367,7 +380,7 @@ ngx_http_combine_server_singlets(ngx_conf_t *cf, ngx_command_t *cmd, void *conf)
             {
                 if (ngx_atoi(value[2].data, value[2].len) == NGX_ERROR) {
                     ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
-                                       "second parameter \"%V\" must be an "
+                                       "field width \"%V\" must be an "
                                        "integer value", &value[2]);
                     return NGX_CONF_ERROR;
                 }
@@ -463,7 +476,11 @@ ngx_http_combine_server_singlets(ngx_conf_t *cf, ngx_command_t *cmd, void *conf)
         ngx_memcpy(usn, uscf->servers->elts,
                    sizeof(ngx_http_upstream_server_t) * uscf->servers->nelts);
         for (j = 0; j < uscf->servers->nelts; ++j) {
-            usn[j].backup = i == j ? 0 : 1;
+            if (nobackup) {
+                usn[j].down = i == j ? usn[j].down : 1;
+            } else {
+                usn[j].backup = i == j ? 0 : 1;
+            }
         }
 
         /*ngx_conf_log_error(NGX_LOG_ERR, cf, 0,*/

test/t/basic.t

@@ -3,7 +3,7 @@
 use Test::Nginx::Socket;
 
 repeat_each(2);
-plan tests => repeat_each() * (2 * (blocks() + 2));
+plan tests => repeat_each() * (2 * (blocks() + 3));
 
 no_shuffle();
 run_tests();
@@ -30,6 +30,11 @@ __DATA__
         combine_server_singlets byname;
         combine_server_singlets _tmp_ 2;
     }
+    upstream u4 {
+        server localhost:8020;
+        server localhost:8030;
+        combine_server_singlets _single_ nobackup;
+    }
 
     upstream u01 {
         server localhost:8040;
@@ -59,6 +64,12 @@ __DATA__
         next_upstream_statuses error timeout 5xx;
         intercept_statuses 5xx /Internal/failover;
     }
+    upstrand us4 {
+        upstream ~^u4_single_ blacklist_interval=60s;
+        order per_request;
+        next_upstream_statuses 5xx;
+        intercept_statuses 5xx /Internal/failover;
+    }
 
     proxy_read_timeout 5s;
     proxy_intercept_errors on;
@@ -136,6 +147,9 @@ __DATA__
         location /us3 {
             proxy_pass http://$upstrand_us3;
         }
+        location /us4 {
+            proxy_pass http://$upstrand_us4;
+        }
         location /echo/us1 {
             echo $upstrand_us1;
         }
@@ -260,3 +274,10 @@ sub {
 In 8060
 --- error_code: 200
 
+=== TEST 11: combined upstreams singlets in upstrand with no round-robin
+--- request eval
+["GET /us4", "GET /us4"]
+--- response_body eval
+["Passed to backend1\n", "Passed to backend1\n"]
+--- error_code eval: [200, 200]
+