allow attribute weight=N in directive add_upstream

lyokha · Nov 6, 2023 · 5df6618 · 5df6618
1 parent 8934cdf
commit 5df6618
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Showing 2 changed files with 32 additions and 7 deletions.
diff --git a/README.md b/README.md
@@ -24,9 +24,11 @@ Directive add_upstream
 ----------------------
 
 Populates the host upstream with servers listed in an already defined upstream
-specified by the mandatory 1st parameter of the directive. Optional 2nd
-parameter may have only value *backup* which marks all servers of the sourced
-upstream as backup.
+specified by the mandatory 1st parameter of the directive. The server attributes
+such as weights, max_fails and others are kept in the host upstream. Optional
+parameters may include values *backup* to mark all servers of the sourced
+upstream as backup servers and *weight=N* to calibrate weights of servers of the
+sourced upstream by multiplying them by factor *N*.
 
 ### An example
 

diff --git a/src/ngx_http_combined_upstreams_module.c b/src/ngx_http_combined_upstreams_module.c
@@ -44,7 +44,7 @@ static ngx_int_t ngx_http_upstream_init_extend_single_peers(ngx_conf_t *cf,
 static ngx_command_t  ngx_http_combined_upstreams_commands[] = {
 
     { ngx_string("add_upstream"),
-      NGX_HTTP_UPS_CONF|NGX_CONF_TAKE12,
+      NGX_HTTP_UPS_CONF|NGX_CONF_TAKE123,
       ngx_http_add_upstream,
       0,
       0,
@@ -257,6 +257,7 @@ ngx_http_add_upstream(ngx_conf_t *cf, ngx_command_t *cmd, void *conf)
     ngx_http_upstream_server_t     *us;
     ngx_str_t                      *value;
     ngx_uint_t                      backup = 0;
+    ngx_int_t                       weight = 0;
 
     umcf = ngx_http_conf_get_module_main_conf(cf, ngx_http_upstream_module);
     uscf = ngx_http_conf_get_module_srv_conf(cf, ngx_http_upstream_module);
@@ -270,12 +271,29 @@ ngx_http_add_upstream(ngx_conf_t *cf, ngx_command_t *cmd, void *conf)
         return NGX_CONF_ERROR;
     }
 
-    if (cf->args->nelts == 3) {
-        if (ngx_strncmp(value[2].data, "backup", 6) == 0) {
+    for (i = 2; i < cf->args->nelts; i++) {
+        if (ngx_strncmp(value[i].data, "backup", 6) == 0) {
+            if (backup) {
+                ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
+                            "parameter \"backup\" has been already declared");
+                return NGX_CONF_ERROR;
+            }
             backup = 1;
+        } else if (ngx_strncmp(value[i].data, "weight=", 7) == 0) {
+            if (weight) {
+                ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
+                            "parameter \"weight\" has been already declared");
+                return NGX_CONF_ERROR;
+            }
+            weight = ngx_atoi(value[i].data + 7, value[i].len - 7);
+            if (weight < 1) {
+                ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
+                    "parameter \"weight\" must be a positive integer value");
+                return NGX_CONF_ERROR;
+            }
         } else {
             ngx_conf_log_error(NGX_LOG_EMERG, cf, 0, "invalid parameter \"%V\"",
-                               &value[2]);
+                               &value[i]);
             return NGX_CONF_ERROR;
         }
     }
@@ -303,6 +321,11 @@ ngx_http_add_upstream(ngx_conf_t *cf, ngx_command_t *cmd, void *conf)
                     us[j].backup = 1;
                 }
             }
+            if (weight) {
+                for (j = 0; j < uscfp[i]->servers->nelts; j++) {
+                    us[j].weight *= weight;
+                }
+            }
 
             return NGX_CONF_OK;
         }