[balancer] resty balancer doesn't fall back to the default 80 port, :…

…set_peer allows providing an explicit port

CHANGELOG.md

@@ -4,6 +4,12 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](http://keepachangelog.com/) 
 and this project adheres to [Semantic Versioning](http://semver.org/).
 
+## [Unreleased]
+
+### Changed
+
+- Changed the way `resty.balancer` sets the default port, in case no port is specified for the upstream [PR #662](https://github.com/3scale/apicast/pull/662)
+
 ## [3.2.0-beta3] - 2018-03-20
 
 ### Fixed

gateway/src/apicast/balancer.lua

@@ -1,13 +1,22 @@
 local round_robin = require 'resty.balancer.round_robin'
+local resty_url = require 'resty.url'
+local empty = {}
 
 local _M = { default_balancer = round_robin.new() }
 
+local function get_default_port(upstream_url)
+  local url = resty_url.split(upstream_url) or empty
+  local scheme = url[1] or 'http'
+  return resty_url.default_port(scheme)
+end
+
 function _M.call(_, _, balancer)
   balancer = balancer or _M.default_balancer
   local host = ngx.var.proxy_host -- NYI: return to lower frame
   local peers = balancer:peers(ngx.ctx[host])
 
-  local peer, err = balancer:set_peer(peers)
+  local port = get_default_port(ngx.var.proxy_pass)
+  local peer, err = balancer:set_peer(peers, port)
 
   if not peer then
     ngx.status = ngx.HTTP_SERVICE_UNAVAILABLE

gateway/src/resty/balancer.lua

@@ -30,7 +30,7 @@ local function new_peer(server, port)
 
   return {
     address,
-    tonumber(server.port or port or 80, 10)
+    tonumber(server.port or port, 10) or nil
   }
 end
 
@@ -41,7 +41,7 @@ local function convert_servers(servers, port)
   for i =1, #servers do
     local peer = new_peer(servers[i], port)
 
-    if peer and #peer == 2 then
+    if peer then
       insert(peers, peer)
     else
       ngx.log(ngx.INFO, 'skipping peer because it misses address or port')
@@ -87,7 +87,7 @@ function _M.select_peer(self, peers)
   return peer
 end
 
-function _M.set_peer(self, peers)
+function _M.set_peer(self, peers, default_port)
   local balancer = self.balancer
 
   if not balancer then
@@ -101,7 +101,7 @@ function _M.set_peer(self, peers)
     return nil, err or 'no peer found'
   end
 
-  address, port = peer[1], peer[2]
+  address, port = peer[1], peer[2] or default_port
 
   if not address or not port then
     return nil, 'peer missing address or port'

spec/resty/balancer_spec.lua

@@ -52,6 +52,19 @@ describe('resty.balancer', function()
       assert.truthy(ok)
       assert.spy(b.balancer.set_current_peer).was.called_with('127.0.0.2', 8091)
     end)
+
+    it('works with default port', function()
+      local peers = {
+        { '127.0.0.2' }
+      }
+      b.balancer.set_current_peer = spy.new(function() return true end)
+
+      local ok, err = b:set_peer(peers, 443)
+
+      assert.falsy(err)
+      assert.truthy(ok)
+      assert.spy(b.balancer.set_current_peer).was.called_with('127.0.0.2', 443)
+    end)
   end)
 
   describe('round-robin balancer', function()