Remove support to toggle response buffering

Turning off proxy_buffering seems like a bad practice so this commit
is to remove response buffering support from the policy

gateway/conf.d/apicast.conf

@@ -84,23 +84,6 @@ location @upstream {
   header_filter_by_lua_block { require('apicast.executor'):header_filter() }
 }
 
-location @upstream_unbuffered {
-  internal;
-
-  rewrite_by_lua_block {
-    require('resty.ctx').apply()
-  }
-
-  proxy_request_buffering off;
-  proxy_buffering off;
-  {% include "conf.d/upstream_shared.conf" %}
-
-  # these are duplicated so when request is redirected here those phases are executed
-  post_action @out_of_band_authrep_action;
-  body_filter_by_lua_block { require('apicast.executor'):body_filter() }
-  header_filter_by_lua_block { require('apicast.executor'):header_filter() }
-}
-
 location @upstream_request_unbuffered {
   internal;
 
@@ -117,22 +100,6 @@ location @upstream_request_unbuffered {
   header_filter_by_lua_block { require('apicast.executor'):header_filter() }
 }
 
-location @upstream_response_buffering {
-  internal;
-
-  rewrite_by_lua_block {
-    require('resty.ctx').apply()
-  }
-
-  proxy_buffering off;
-  {% include "conf.d/upstream_shared.conf" %}
-
-  # these are duplicated so when request is redirected here those phases are executed
-  post_action @out_of_band_authrep_action;
-  body_filter_by_lua_block { require('apicast.executor'):body_filter() }
-  header_filter_by_lua_block { require('apicast.executor'):header_filter() }
-}
-
 location / {
   set $cached_key '';
   set $credentials '';

gateway/src/apicast/policy/buffering/apicast-policy.json

@@ -1,9 +1,9 @@
 {
   "$schema": "http://apicast.io/policy-v1/schema#manifest#",
-  "name": "3scale Request/Response buffering",
-  "summary": "Controls how 3scale buffer request/response",
+  "name": "3scale Request buffering",
+  "summary": "Controls how 3scale buffer request",
   "description": [
-      "Configures the buffering for request and response"
+      "Configures the buffering for request"
   ],
   "version": "builtin",
   "configuration": {
@@ -13,11 +13,6 @@
         "description": "Request Buffering mode",
         "type": "boolean",
         "default": true
-      },
-      "response_buffering": {
-        "description": "Response Buffering mode",
-        "type": "boolean",
-        "default": true
       }
     }
   }

gateway/src/apicast/policy/buffering/buffering.lua

@@ -12,14 +12,12 @@ local new = _M.new
 function _M.new(config)
   local self = new(config)
   self.request_buffering = config.request_buffering
-  self.response_buffering = config.response_buffering
   return self
 end
 
 function _M:export()
   return {
     request_buffering = self.request_buffering,
-    response_buffering = self.response_buffering
   }
 end
 

gateway/src/apicast/upstream.lua

@@ -215,14 +215,8 @@ local function get_upstream_location_name(context)
         return context.upstream_location_name
     end
     if context.request_buffering == false then
-        if context.response_buffering == false then
-            return "@upstream_unbuffered"
-        end
         return "@upstream_request_unbuffered"
     end
-    if context.response_buffering == false then
-        return "@upstream_response_unbuffered"
-    end
 end
 
 --- Execute the upstream.

spec/policy/buffering/buffering_spec.lua

@@ -7,19 +7,16 @@ describe('Buffering policy', function()
         local exported = policy:export()
 
         assert.same(true, exported.request_buffering)
-        assert.same(true, exported.response_buffering)
     end)
 
     it('accepts configuration', function()
         local config_buffering = {
             request_buffering = false,
-            response_buffering = false,
         }
         local policy = BufferingPolicy.new(config_buffering)
         local exported = policy:export()
 
         assert.same(false, exported.request_buffering)
-        assert.same(false, exported.response_buffering)
     end)
   end)
 end)

spec/upstream_spec.lua

@@ -220,15 +220,9 @@ describe('Upstream', function()
         it('executes the upstream location when request_buffering provided in the context', function()
             local contexts = {
                 ["buffered_request"] = {ctx={request_buffering=true}, upstream_location="@upstream"},
-                ["buffered_response"] = {ctx={response_buffering=true}, upstream_location="@upstream"},
                 ["unbuffered_request"] = {ctx={request_buffering=false}, upstream_location="@upstream_request_unbuffered"},
-                ["unbuffered_response"] = {ctx={response_buffering=false}, upstream_location="@upstream_response_unbuffered"},
-                ["unbuffered"] = {ctx={request_buffering=false, response_buffering=false}, upstream_location="@upstream"},
                 ["upstream_location and buffered_request"] = {ctx={upstream_location_name="@grpc", request_buffering=true}, upstream_location="@grpc"},
-                ["upstream_location and buffered_response"] = {ctx={upstream_location_name="@grpc", response_buffering=true}, upstream_location="@grpc"},
                 ["upstream_location and unbuffered_request"] = {ctx={upstream_location_name="@grpc", request_buffering=false}, upstream_location="@grpc"},
-                ["upstream_location and unbuffered_response"] = {ctx={upstream_location_name="@grpc", response_buffering=false}, upstream_location="@grpc"},
-                ["upstream_location and unbuffered"] = {ctx={upstream_location_name="@grpc", request_buffering=false, response_buffering=false}, upstream_location="@grpc"}
             }
 
             for _, value in pairs(contexts) do
@@ -239,14 +233,6 @@ describe('Upstream', function()
             end
         end)
 
-        it('executes the upstream location when response_buffering provided in the context', function()
-            local upstream = Upstream.new('http://localhost')
-
-            upstream:call({response_buffering=true})
-
-            assert.spy(ngx.exec).was_called_with("@upstream")
-        end)
-
         it('skips executing the upstream location when missing', function()
             local upstream = Upstream.new('http://localhost')
             upstream.location_name = nil