t/apicast-policy-cors: add test with custom config

t/apicast-policy-cors.t

@@ -38,9 +38,15 @@ Access-Control-Request-Method: GET
 --- no_error_log
 [error]
 
-=== TEST 2: CORS actual request
-This test a CORS actual (not preflight) request. The only difference with a
+=== TEST 2: CORS actual request with default config
+This tests a CORS actual (not preflight) request. The only difference with a
 non-CORS request is that the CORS headers will be included in the response.
+In this test, we are not using a custom config for the CORS policy. This means
+that the response will contain the default CORS headers. By default, all of
+them (allow-headers, allow-methods, etc.) simply match the headers received in
+the request. So for example, if the request sets the 'Origin' header to
+'example.com' the response will set 'Access-Control-Allow-Origin' to
+'example.com'.
 --- configuration
 {
   "services": [
@@ -93,7 +99,67 @@ Access-Control-Allow-Methods: GET
 Access-Control-Allow-Origin: http://example.com
 Access-Control-Allow-Credentials: true
 --- error_code: 200
---- error_log
-apicast cache miss key: 42:value:usage%5Bhits%5D=2
+--- no_error_log
+[error]
+
+=== TEST 3: CORS actual request with custom config
+This tests a CORS actual (not preflight) request. We use a custom config to set
+the CORS headers in the response.
+--- configuration
+{
+  "services": [
+    {
+      "id": 42,
+      "backend_version":  1,
+      "backend_authentication_type": "service_token",
+      "backend_authentication_value": "token-value",
+      "proxy": {
+        "policy_chain": [
+          { "name": "policy.cors",
+            "configuration": { "allow_headers": [ "X-Custom-Header-1", "X-Custom-Header-2" ],
+                               "allow_methods": [ "POST", "GET", "OPTIONS" ],
+                               "allow_origin" : "*",
+                               "allow_credentials": false } },
+          { "name": "apicast" }
+        ],
+        "api_backend": "http://test:$TEST_NGINX_SERVER_PORT/",
+        "proxy_rules": [
+          { "pattern": "/", "http_method": "GET", "metric_system_name": "hits", "delta": 2 }
+        ]
+      }
+    }
+  ]
+}
+--- backend
+  location /transactions/authrep.xml {
+    content_by_lua_block {
+      local expected = "service_token=token-value&service_id=42&usage%5Bhits%5D=2&user_key=value"
+      local args = ngx.var.args
+      if args == expected then
+        ngx.exit(200)
+      else
+        ngx.log(ngx.ERR, expected, ' did not match: ', args)
+        ngx.exit(403)
+      end
+    }
+  }
+--- upstream
+  location / {
+     echo 'yay, api backend: $http_host';
+  }
+--- request
+GET /?user_key=value
+--- more_headers
+Origin: http://example.com
+Access-Control-Request-Method: GET
+Access-Control-Request-Headers: Content-Type
+--- response_body
+yay, api backend: test
+--- response_headers
+Access-Control-Allow-Headers: X-Custom-Header-1, X-Custom-Header-2
+Access-Control-Allow-Methods: POST, GET, OPTIONS
+Access-Control-Allow-Origin: *
+Access-Control-Allow-Credentials: false
+--- error_code: 200
 --- no_error_log
 [error]