[t] use one base class

CHANGELOG.md

@@ -20,6 +20,7 @@ and this project adheres to [Semantic Versioning](http://semver.org/).
 - URI params in POST requests are now taken into account when matching mapping rules [PR #437](https://github.com/3scale/apicast/pull/437)
 - Increased number of background timers and connections in the cosocket pool [PR #290](https://github.com/3scale/apicast/pull/290)
 - Make OAuth tokens TTL configurable [PR #448](https://github.com/3scale/apicast/pull/448)
+- Detect when being executed in Test::Nginx and use default backend accordingly [PR #458](https://github.com/3scale/apicast/pull/458)
 
 ### Fixed
 

apicast/src/configuration.lua

@@ -6,7 +6,6 @@ local len = string.len
 local format = string.format
 local pairs = pairs
 local type = type
-local unpack = unpack
 local error = error
 local tostring = tostring
 local next = next
@@ -129,12 +128,34 @@ end
 
 local Service = require 'configuration.service'
 
+local noop = function() end
+local function readonly_table(table)
+    return setmetatable({}, { __newindex = noop, __index = table })
+end
+
+local empty_t = readonly_table()
+
+local function backend_endpoint(proxy)
+    local backend_endpoint_override = resty_url.parse(env.get("BACKEND_ENDPOINT_OVERRIDE"))
+    local backend = backend_endpoint_override or proxy.backend or empty_t
+
+    if backend == empty_t then
+        local test_nginx_server_port = env.get('TEST_NGINX_SERVER_PORT')
+        if test_nginx_server_port then
+            return { endpoint =  'http://127.0.0.1:' .. test_nginx_server_port }
+        else
+            return nil
+        end
+    else
+        return { endpoint = backend.endpoint or tostring(backend), host = backend.host }
+    end
+end
+
 function _M.parse_service(service)
   local backend_version = tostring(service.backend_version)
-  local proxy = service.proxy or {}
-  local backend = proxy.backend or {}
-  local backend_endpoint_override = env.get("BACKEND_ENDPOINT_OVERRIDE")
-  local _, _, _, backend_host_override = unpack(resty_url.split(backend_endpoint_override) or {})
+  local proxy = service.proxy or empty_t
+  local backend = backend_endpoint(proxy)
+
 
   return Service.new({
       id = tostring(service.id or 'default'),
@@ -161,10 +182,7 @@ function _M.parse_service(service)
         type = service.backend_authentication_type,
         value = service.backend_authentication_value
       },
-      backend = {
-        endpoint = backend_endpoint_override or backend.endpoint,
-        host = backend_host_override or backend.host
-      },
+      backend = backend,
       oidc = {
         issuer_endpoint = proxy.oidc_issuer_endpoint ~= ngx.null and proxy.oidc_issuer_endpoint
       },

spec/configuration_spec.lua

@@ -25,16 +25,6 @@ describe('Configuration object', function()
       assert.same('example.com', config.hostname_rewrite)
     end)
 
-    it('overrides backend endpoint from ENV', function()
-      env.set('BACKEND_ENDPOINT_OVERRIDE', 'https://backend.example.com')
-
-      local config = configuration.parse_service({ proxy = {
-        backend = { endpoint = 'http://example.com', host = 'foo.example.com' }
-      }})
-
-      assert.same('https://backend.example.com', config.backend.endpoint)
-      assert.same('backend.example.com', config.backend.host)
-    end)
 
     it('has a default message, content-type, and status for the auth failed error', function()
       local config = configuration.parse_service({})
@@ -67,6 +57,38 @@ describe('Configuration object', function()
       assert.same('text/plain; charset=utf-8', config.limits_exceeded_headers)
       assert.equals(429, config.limits_exceeded_status)
     end)
+
+    describe('backend', function()
+      it('defaults to nothing', function()
+        local config = configuration.parse_service({ proxy = {
+          backend = nil
+        }})
+
+        assert.falsy(config.backend)
+      end)
+
+      it('is overriden from ENV', function()
+        env.set('BACKEND_ENDPOINT_OVERRIDE', 'https://backend.example.com')
+
+        local config = configuration.parse_service({ proxy = {
+          backend = { endpoint = 'http://example.com', host = 'foo.example.com' }
+        }})
+
+        assert.same('https://backend.example.com', config.backend.endpoint)
+        assert.same('backend.example.com', config.backend.host)
+      end)
+
+      it('detects TEST_NGINX_SERVER_PORT', function()
+        env.set('TEST_NGINX_SERVER_PORT', '1954')
+
+        local config = configuration.parse_service({ proxy = {
+          backend = nil
+        }})
+
+        assert.same('http://127.0.0.1:1954', config.backend.endpoint)
+        assert.falsy(config.backend.host)
+      end)
+    end)
   end)
 
   describe('.filter_services', function()