From fb2fd43e0805a3633c090bbeb6d9bc06d22cf7d1 Mon Sep 17 00:00:00 2001
From: Dhruv Sarawagi <62890722+dhruvd11@users.noreply.github.com>
Date: Thu, 12 Aug 2021 15:55:19 +0530
Subject: [PATCH] feat: add support for local routes in upstream url (#3)

Co-authored-by: Dhruv Sarawagi <dhruv.sarawagi@D11-Dhruv.Sarawagi-TEMP>
---
 kong/plugins/advanced-router/handler.lua | 22 ++++++++++++++++++++--
 kong/plugins/advanced-router/io.lua      |  3 ++-
 kong/plugins/advanced-router/utils.lua   | 10 ++++++++++
 3 files changed, 32 insertions(+), 3 deletions(-)

diff --git a/kong/plugins/advanced-router/handler.lua b/kong/plugins/advanced-router/handler.lua
index 7180527..d1610ff 100644
--- a/kong/plugins/advanced-router/handler.lua
+++ b/kong/plugins/advanced-router/handler.lua
@@ -2,10 +2,12 @@ local inspect = require("inspect")
 local cjson_safe = require "cjson.safe"
 local url = require "socket.url"
 local date = require "date"
+local pl_tablex = require "pl.tablex"
 
 local get_io_data = require("kong.plugins.advanced-router.io").get_io_data
 local extract = require("kong.plugins.advanced-router.utils").extract
 local replaceStringEnvVariables = require("kong.plugins.advanced-router.utils").replaceStringEnvVariables
+local build_url = require("kong.plugins.advanced-router.utils").build_url
 
 local AdvancedRouterHandler = {}
 
@@ -14,6 +16,17 @@ AdvancedRouterHandler.VERSION = "1.0.0"
 
 local boolean_functions = {}
 
+local kong_proxy_port
+
+function get_poxy_port()
+    local http_listener = pl_tablex.filter(kong.configuration.proxy_listeners, function(x)
+        if not x.ssl then
+            return true
+        end
+    end)
+    return http_listener[1]['port']
+end
+
 function get_current_timestamp_utc()
     return date.diff(date(true), date(1970, 1, 1)):spanseconds()
 end
@@ -30,7 +43,8 @@ function generate_boolean_function(proposition)
     if proposition['condition'] == 'default' then
         return assert(loadstring("return " .. "\"" .. proposition["upstream_url"] .. "\""))
     end
-    return assert(loadstring("if " .. proposition["condition"] .. "then return " .. "\"" .. proposition["upstream_url"] .. "\"" .. " end"))
+    local upstream_url = build_url(proposition["upstream_url"], kong_proxy_port)
+    return assert(loadstring("if " .. proposition["condition"] .. "then return " .. "\"" .. upstream_url .. "\"" .. " end"))
 end
 
 function get_upstream_url(conf)
@@ -75,7 +89,7 @@ function set_upstream(upstream_url)
 end
 
 function AdvancedRouterHandler:access(conf)
-    local io_data, err = get_io_data(conf)
+    local io_data, err = get_io_data(pl_tablex.merge(conf, { kong_proxy_port = kong_proxy_port }, true))
     if err then
         kong.log.err("Error in getting io data" .. inspect(err))
         return kong.response.exit(500, { error = "Error in getting io data" .. inspect(err) })
@@ -90,6 +104,10 @@ function AdvancedRouterHandler:access(conf)
     set_upstream(upstream_url)
 end
 
+function AdvancedRouterHandler:init_worker()
+    kong_proxy_port = get_poxy_port()
+end
+
 return AdvancedRouterHandler
 
 
diff --git a/kong/plugins/advanced-router/io.lua b/kong/plugins/advanced-router/io.lua
index 3d5a05e..1060c7b 100644
--- a/kong/plugins/advanced-router/io.lua
+++ b/kong/plugins/advanced-router/io.lua
@@ -6,6 +6,7 @@ local generate_signature_hash = require("kong.plugins.advanced-router.utils").ge
 local extract = require "kong.plugins.advanced-router.utils".extract
 local belongs = require "kong.plugins.advanced-router.utils".belongs
 local replaceStringEnvVariables = require "kong.plugins.advanced-router.utils".replaceStringEnvVariables
+local build_url = require("kong.plugins.advanced-router.utils").build_url
 
 local _M = {}
 
@@ -122,7 +123,7 @@ end
 function create_io_request(conf)
     local io_request = extract_io_data_from_request(conf)
     kong.log.debug("conf" .. inspect(conf))
-    io_request["io_url"] = replaceStringEnvVariables(conf.io_url)
+    io_request["io_url"] = build_url(replaceStringEnvVariables(conf.io_url), conf.kong_proxy_port)
     io_request["io_http_method"] = conf.io_http_method
     return io_request
 end
diff --git a/kong/plugins/advanced-router/utils.lua b/kong/plugins/advanced-router/utils.lua
index 1ac96a5..930cd48 100644
--- a/kong/plugins/advanced-router/utils.lua
+++ b/kong/plugins/advanced-router/utils.lua
@@ -2,6 +2,7 @@ local pl_utils = require "pl.utils"
 local sha256 = require "resty.sha256"
 local encode_base64 = ngx.encode_base64
 local inspect = require "inspect"
+local url = require "socket.url"
 
 local _M = {}
 
@@ -55,4 +56,13 @@ function _M.belongs(val, tbl)
     return false
 end
 
+function _M.build_url(upstream_url, kong_proxy_port)
+    local parsed_url = url.parse(upstream_url);
+    if not parsed_url["host"] then
+        parsed_url["host"] = "localhost"
+        parsed_url["port"] = kong_proxy_port
+    end
+    return url.build(parsed_url)
+end
+
 return _M