Live Nginx (re)configuration without reloading (#2174)

rootfs/etc/nginx/lua/configuration.lua

@@ -0,0 +1,41 @@
+-- this is the Lua representation of Configuration struct in internal/ingress/types.go
+local configuration_data = ngx.shared.configuration_data
+
+local _M = {}
+
+function _M.get_backends_data()
+  return configuration_data:get("backends")
+end
+
+function _M.call()
+  if ngx.var.request_method ~= "POST" and ngx.var.request_method ~= "GET" then
+    ngx.status = ngx.HTTP_BAD_REQUEST
+    ngx.print("Only POST and GET requests are allowed!")
+    return
+  end
+
+  if ngx.var.request_uri ~= "/configuration/backends" then
+    ngx.status = ngx.HTTP_NOT_FOUND
+    ngx.print("Not found!")
+    return
+  end
+
+  if ngx.var.request_method == "GET" then
+    ngx.status = ngx.HTTP_OK
+    ngx.print(_M.get_backends_data())
+    return
+  end
+
+  ngx.req.read_body()
+
+  local success, err = configuration_data:set("backends", ngx.req.get_body_data())
+  if not success then
+    ngx.log(ngx.ERR, "error while saving configuration: " .. tostring(err))
+    ngx.status = ngx.HTTP_BAD_REQUEST
+    return
+  end
+
+  ngx.status = ngx.HTTP_CREATED
+end
+
+return _M