perf(clustering) do granular hashes like #8519 does for old protocol.

kong/clustering/init.lua

@@ -192,6 +192,18 @@ function _M:calculate_config_hash(config_table)
   }
 end
 
+local function fill_empty_hashes(hashes)
+  for _, field_name in ipairs{
+    "config",
+    "routes",
+    "services",
+    "plugins",
+    "upstreams",
+    "targets",
+  } do
+    hashes[field_name] = hashes[field_name] or DECLARATIVE_EMPTY_CONFIG_HASH
+  end
+end
 
 function _M:request_version_negotiation()
   local response_data, err = version_negotiation.request_version_handshake(self.conf, self.cert, self.cert_key)
@@ -212,6 +224,10 @@ function _M:update_config(config_table, config_hash, update_cache, hashes)
     config_hash, hashes = self:calculate_config_hash(config_table)
   end
 
+  if hashes then
+    fill_empty_hashes(hashes)
+  end
+
   local current_hash = declarative.get_current_hash()
   if current_hash == config_hash then
     ngx_log(ngx_DEBUG, _log_prefix, "same config received from control plane, ",
@@ -234,8 +250,8 @@ function _M:update_config(config_table, config_hash, update_cache, hashes)
   -- NOTE: no worker mutex needed as this code can only be
   -- executed by worker 0
 
-  local res, err =
-  declarative.load_into_cache_with_events(entities, meta, new_hash, hashes)
+  local res
+  res, err = declarative.load_into_cache_with_events(entities, meta, new_hash, hashes)
   if not res then
     return nil, err
   end

kong/clustering/wrpc_control_plane.lua

@@ -151,7 +151,7 @@ function _M:export_deflated_reconfigure_payload()
     end
   end
 
-  local config_hash = self:calculate_config_hash(config_table)
+  local config_hash, hashes = self:calculate_config_hash(config_table)
   config_version = config_version + 1
 
   -- store serialized plugins map for troubleshooting purposes
@@ -162,7 +162,8 @@ function _M:export_deflated_reconfigure_payload()
   self.config_call_rpc, self.config_call_args = assert(service:encode_args("ConfigService.SyncConfig", {
     config = config_table,
     version = config_version,
-    hash = config_hash,
+    config_hash = config_hash,
+    hashes = hashes,
   }))
 
   return config_table, nil

kong/clustering/wrpc_data_plane.lua

@@ -84,7 +84,8 @@ local function get_config_service()
         data.config.format_version = nil
 
         peer.config_obj.next_config = data.config
-        peer.config_obj.next_hash = data.hash
+        peer.config_obj.next_hash = data.config_hash
+        peer.config_obj.next_hashes = data.hashes
         peer.config_obj.next_config_version = tonumber(data.version)
         if peer.config_semaphore:count() <= 0 then
           -- the following line always executes immediately after the `if` check
@@ -196,11 +197,12 @@ function _M:communicate(premature)
         end
         local config_table = self.next_config
         local config_hash  = self.next_hash
+        local hashes = self.next_hashes
         if config_table and self.next_config_version > last_config_version then
           ngx_log(ngx_INFO, _log_prefix, "received config #", self.next_config_version, log_suffix)
 
           local pok, res
-          pok, res, err = xpcall(self.update_config, debug.traceback, self, config_table, config_hash, true)
+          pok, res, err = xpcall(self.update_config, debug.traceback, self, config_table, config_hash, true, hashes)
           if pok then
             last_config_version = self.next_config_version
             if not res then
@@ -214,6 +216,7 @@ function _M:communicate(premature)
           if self.next_config == config_table then
             self.next_config = nil
             self.next_hash = nil
+            self.next_hashes = nil
           end
         end
 

kong/db/declarative/init.lua

@@ -993,7 +993,7 @@ do
   local DECLARATIVE_LOCK_KEY = "declarative:lock"
 
   -- make sure no matter which path it exits, we released the lock.
-  function declarative.load_into_cache_with_events(entities, meta, hash)
+  function declarative.load_into_cache_with_events(entities, meta, hash, hashes)
     local kong_shm = ngx.shared.kong
 
     local ok, err = kong_shm:add(DECLARATIVE_LOCK_KEY, 0, DECLARATIVE_LOCK_TTL)
@@ -1007,7 +1007,7 @@ do
       return nil, err
     end
 
-    ok, err = load_into_cache_with_events_no_lock(entities, meta, hash)
+    ok, err = load_into_cache_with_events_no_lock(entities, meta, hash, hashes)
     kong_shm:delete(DECLARATIVE_LOCK_KEY)
 
     return ok, err

kong/include/kong/services/config/v1/config.proto

@@ -85,6 +85,15 @@ message PluginVersion {
   string version = 2;
 }
 
+message GranularHashes {
+  string config = 1;
+  string routes = 2;
+  string services = 3;
+  string plugins = 4;
+  string upstreams = 5;
+  string targets = 6;
+}
+
 message SyncConfigRequest {
   // Config represents a configuration of Kong Gateway.
   // This is same as the declarative configuration of Kong.
@@ -101,7 +110,8 @@ message SyncConfigRequest {
   uint64 version = 2;
 
   // raw binary hash of the config data.
-  string hash = 3;
+  string config_hash = 3;
+  GranularHashes hashes = 4;
 }
 
 message SyncConfigResponse {

spec/01-unit/19-hybrid/02-clustering_spec.lua

@@ -209,5 +209,71 @@ describe("kong.clustering", function()
       end
     end)
 
+    describe("granular hashes", function()
+      local DECLARATIVE_EMPTY_CONFIG_HASH = require("kong.constants").DECLARATIVE_EMPTY_CONFIG_HASH
+
+      it("filled with empty hash values for missing config fields", function()
+        local value = {}
+
+        for _ = 1, 10 do
+          local hash, hashes = clustering.calculate_config_hash(clustering, value)
+          assert.is_string(hash)
+          assert.equal("aaf38faf0b5851d711027bb4d812d50d", hash)
+          assert.is_table(hashes)
+          assert.same({
+            config = "aaf38faf0b5851d711027bb4d812d50d",
+            routes = DECLARATIVE_EMPTY_CONFIG_HASH,
+            services = DECLARATIVE_EMPTY_CONFIG_HASH,
+            plugins = DECLARATIVE_EMPTY_CONFIG_HASH,
+            upstreams = DECLARATIVE_EMPTY_CONFIG_HASH,
+            targets = DECLARATIVE_EMPTY_CONFIG_HASH,
+          }, hashes)
+        end
+      end)
+
+      it("has sensible values for existing fields", function()
+        local value = {
+          routes = {},
+          services = {},
+          plugins = {},
+        }
+
+        for _ = 1, 10 do
+          local hash, hashes = clustering.calculate_config_hash(clustering, value)
+          assert.is_string(hash)
+          assert.equal("768533baebe6e0d46de8d5f8a0c05bf0", hash)
+          assert.is_table(hashes)
+          assert.same({
+            config = "768533baebe6e0d46de8d5f8a0c05bf0",
+            routes = "99914b932bd37a50b983c5e7c90ae93b",
+            services = "99914b932bd37a50b983c5e7c90ae93b",
+            plugins = "99914b932bd37a50b983c5e7c90ae93b",
+            upstreams = DECLARATIVE_EMPTY_CONFIG_HASH,
+            targets = DECLARATIVE_EMPTY_CONFIG_HASH,
+          }, hashes)
+        end
+
+        value = {
+          upstreams = {},
+          targets = {},
+        }
+
+        for _ = 1, 10 do
+          local hash, hashes = clustering.calculate_config_hash(clustering, value)
+          assert.is_string(hash)
+          assert.equal("6c5fb69169a0fabb24dcfa3a5d7a14b0", hash)
+          assert.is_table(hashes)
+          assert.same({
+            config = "6c5fb69169a0fabb24dcfa3a5d7a14b0",
+            routes = DECLARATIVE_EMPTY_CONFIG_HASH,
+            services = DECLARATIVE_EMPTY_CONFIG_HASH,
+            plugins = DECLARATIVE_EMPTY_CONFIG_HASH,
+            upstreams = "99914b932bd37a50b983c5e7c90ae93b",
+            targets = "99914b932bd37a50b983c5e7c90ae93b",
+          }, hashes)
+        end
+      end)
+    end)
+
   end)
 end)