feat(clustering): CP/DP RPC framework & dynamic log level RPC (#12320)

This PR implements an extensible mechanism where CP and DP nodes can bidirectionally communicate
with each other and perform RPC calls. Which can be used for building complex interactions
such as config sync, debugging, etc.

This PR also implements a simple RPC service for CP to inspect and change the dynamic log level
of the connected DP nodes. The functionality is exposed via a new Admin API endpoint
`/clustering/data-planes/<node-id>/log-level`.

KAG-623
KAG-3751

.requirements

@@ -12,8 +12,9 @@ LIBEXPAT=2.6.2
 LUA_KONG_NGINX_MODULE=a8411f7cf4289049f0bd3e8e40088e7256389ed3 # 0.11.0
 LUA_RESTY_LMDB=7d2581cbe30cde18a8482d820c227ca0845c0ded # 1.4.2
 LUA_RESTY_EVENTS=8448a92cec36ac04ea522e78f6496ba03c9b1fd8 # 0.2.0
-LUA_RESTY_WEBSOCKET=60eafc3d7153bceb16e6327074e0afc3d94b1316 # 0.4.0
+LUA_RESTY_WEBSOCKET=966c69c39f03029b9b42ec0f8e55aaed7d6eebc0 # 0.4.0.1
 ATC_ROUTER=ffd11db657115769bf94f0c4f915f98300bc26b6 # 1.6.2
+SNAPPY=23b3286820105438c5dbb9bc22f1bb85c5812c8a # 1.2.0
 
 # KONG_MANAGER is the admin GUI for the CE gateway
 # Please leave this untouched and use KONG_ADMIN in EE version instead

build/BUILD.bazel

@@ -165,6 +165,7 @@ kong_directory_genrule(
         "//build/ee:bytecode_compile",
         # EE new files
         "//build/ee:luarocks_license",
+        "@snappy//:snappy",
     ] + select({
         "@kong//:licensing_flag": [
             "@kong-licensing",
@@ -235,6 +236,9 @@ kong_directory_genrule(
         tar -cC ${LUAJIT}/share . | tar -xC ${BUILD_DESTDIR}/openresty/luajit/share
         chmod -R "+rw" ${BUILD_DESTDIR}/openresty/luajit
 
+        SNAPPY=${WORKSPACE_PATH}/$(dirname $(echo '$(locations @snappy//:snappy)' | awk '{print $1}'))
+        cp ${SNAPPY}/libsnappy.so ${BUILD_DESTDIR}/kong/lib
+
         LUAROCKS=${WORKSPACE_PATH}/$(dirname '$(location @luarocks//:luarocks_make)')/luarocks_tree
         cp -r ${LUAROCKS}/. ${BUILD_DESTDIR}/.
         rm ${BUILD_DESTDIR}/bin/lapis ${BUILD_DESTDIR}/bin/luarocks-admin

build/openresty/repositories.bzl

@@ -12,6 +12,7 @@ load("//build/openresty/msgpack_c:msgpack_c_repositories.bzl", "msgpack_c_reposi
 load("//build/openresty/wasmx:wasmx_repositories.bzl", "wasmx_repositories")
 load("//build/openresty/wasmx/filters:repositories.bzl", "wasm_filters_repositories")
 load("//build/openresty/brotli:brotli_repositories.bzl", "brotli_repositories")
+load("//build/openresty/snappy:snappy_repositories.bzl", "snappy_repositories")
 
 # This is a dummy file to export the module's repository.
 _NGINX_MODULE_DUMMY_FILE = """
@@ -31,6 +32,7 @@ def openresty_repositories():
     wasmx_repositories()
     wasm_filters_repositories()
     brotli_repositories()
+    snappy_repositories()
 
     openresty_version = KONG_VAR["OPENRESTY"]
 

build/openresty/snappy/BUILD.bazel

@@ -0,0 +1,206 @@
+# Copyright 2023 Google Inc. All Rights Reserved.
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions are
+# met:
+#
+#     * Redistributions of source code must retain the above copyright
+# notice, this list of conditions and the following disclaimer.
+#     * Redistributions in binary form must reproduce the above
+# copyright notice, this list of conditions and the following disclaimer
+# in the documentation and/or other materials provided with the
+# distribution.
+#     * Neither the name of Google Inc. nor the names of its
+# contributors may be used to endorse or promote products derived from
+# this software without specific prior written permission.
+#
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+package(default_visibility = ["//visibility:public"])
+
+licenses(["notice"])
+
+SNAPPY_VERSION = (1, 1, 10)
+
+config_setting(
+    name = "windows",
+    constraint_values = ["@platforms//os:windows"],
+)
+
+cc_library(
+    name = "config",
+    hdrs = ["config.h"],
+    defines = ["HAVE_CONFIG_H"],
+)
+
+cc_library(
+    name = "snappy-stubs-public",
+    hdrs = [":snappy-stubs-public.h"],
+)
+
+cc_library(
+    name = "snappy-stubs-internal",
+    srcs = ["snappy-stubs-internal.cc"],
+    hdrs = ["snappy-stubs-internal.h"],
+    deps = [
+        ":config",
+        ":snappy-stubs-public",
+    ],
+)
+
+cc_library(
+    name = "snappy",
+    srcs = [
+        "snappy.cc",
+        "snappy-c.cc",
+        "snappy-internal.h",
+        "snappy-sinksource.cc",
+    ],
+    hdrs = [
+        "snappy.h",
+        "snappy-c.h",
+        "snappy-sinksource.h",
+    ],
+    copts = select({
+        ":windows": [],
+        "//conditions:default": [
+            "-Wno-sign-compare",
+        ],
+    }),
+    deps = [
+        ":config",
+        ":snappy-stubs-internal",
+        ":snappy-stubs-public",
+    ],
+)
+
+filegroup(
+    name = "testdata",
+    srcs = glob(["testdata/*"]),
+)
+
+cc_library(
+    name = "snappy-test",
+    testonly = True,
+    srcs = [
+        "snappy-test.cc",
+        "snappy_test_data.cc",
+    ],
+    hdrs = [
+        "snappy-test.h",
+        "snappy_test_data.h",
+    ],
+    deps = [":snappy-stubs-internal"],
+)
+
+cc_test(
+    name = "snappy_benchmark",
+    srcs = ["snappy_benchmark.cc"],
+    data = [":testdata"],
+    deps = [
+        ":snappy",
+        ":snappy-test",
+        "//third_party/benchmark:benchmark_main",
+    ],
+)
+
+cc_test(
+    name = "snappy_unittest",
+    srcs = [
+        "snappy_unittest.cc",
+    ],
+    data = [":testdata"],
+    deps = [
+        ":snappy",
+        ":snappy-test",
+        "//third_party/googletest:gtest_main",
+    ],
+)
+
+# Generate a config.h similar to what cmake would produce.
+genrule(
+    name = "config_h",
+    outs = ["config.h"],
+    cmd = """cat <<EOF >$@
+#define HAVE_STDDEF_H 1
+#define HAVE_STDINT_H 1
+#ifdef __has_builtin
+#  if !defined(HAVE_BUILTIN_EXPECT) && __has_builtin(__builtin_expect)
+#    define HAVE_BUILTIN_EXPECT 1
+#  endif
+#  if !defined(HAVE_BUILTIN_CTZ) && __has_builtin(__builtin_ctzll)
+#    define HAVE_BUILTIN_CTZ 1
+#  endif
+#  if !defined(HAVE_BUILTIN_PREFETCH) && __has_builtin(__builtin_prefetech)
+#    define HAVE_BUILTIN_PREFETCH 1
+#  endif
+#elif defined(__GNUC__) && (__GNUC__ > 3 || __GNUC__ == 3 && __GNUC_MINOR__ >= 4)
+#  ifndef HAVE_BUILTIN_EXPECT
+#    define HAVE_BUILTIN_EXPECT 1
+#  endif
+#  ifndef HAVE_BUILTIN_CTZ
+#    define HAVE_BUILTIN_CTZ 1
+#  endif
+#  ifndef HAVE_BUILTIN_PREFETCH
+#    define HAVE_BUILTIN_PREFETCH 1
+#  endif
+#endif
+
+#if defined(_WIN32) && !defined(HAVE_WINDOWS_H)
+#define HAVE_WINDOWS_H 1
+#endif
+
+#ifdef __has_include
+#  if !defined(HAVE_BYTESWAP_H) && __has_include(<byteswap.h>)
+#    define HAVE_BYTESWAP_H 1
+#  endif
+#  if !defined(HAVE_UNISTD_H) && __has_include(<unistd.h>)
+#    define HAVE_UNISTD_H 1
+#  endif
+#  if !defined(HAVE_SYS_ENDIAN_H) && __has_include(<sys/endian.h>)
+#    define HAVE_SYS_ENDIAN_H 1
+#  endif
+#  if !defined(HAVE_SYS_MMAN_H) && __has_include(<sys/mman.h>)
+#    define HAVE_SYS_MMAN_H 1
+#  endif
+#  if !defined(HAVE_SYS_UIO_H) && __has_include(<sys/uio.h>)
+#    define HAVE_SYS_UIO_H 1
+#  endif
+#  if !defined(HAVE_SYS_TIME_H) && __has_include(<sys/time.h>)
+#    define HAVE_SYS_TIME_H 1
+#  endif
+#endif
+
+#ifndef SNAPPY_IS_BIG_ENDIAN
+#  ifdef __s390x__
+#    define SNAPPY_IS_BIG_ENDIAN 1
+#  elif defined(__BYTE_ORDER__) && defined(__ORDER_BIG_ENDIAN__) && __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
+#    define SNAPPY_IS_BIG_ENDIAN 1
+#  endif
+#endif
+EOF
+""",
+)
+
+genrule(
+    name = "snappy_stubs_public_h",
+    srcs = ["snappy-stubs-public.h.in"],
+    outs = ["snappy-stubs-public.h"],
+    # Assume sys/uio.h is available on non-Windows.
+    # Set the version numbers.
+    cmd = ("""sed -e 's/$${HAVE_SYS_UIO_H_01}/!_WIN32/g' \
+           -e 's/$${PROJECT_VERSION_MAJOR}/%d/g' \
+           -e 's/$${PROJECT_VERSION_MINOR}/%d/g' \
+           -e 's/$${PROJECT_VERSION_PATCH}/%d/g' \
+    $< >$@""" % SNAPPY_VERSION),
+)

build/openresty/snappy/snappy_repositories.bzl

@@ -0,0 +1,15 @@
+"""A module defining the dependency snappy"""
+
+load("@bazel_tools//tools/build_defs/repo:git.bzl", "new_git_repository")
+load("@bazel_tools//tools/build_defs/repo:utils.bzl", "maybe")
+load("@kong_bindings//:variables.bzl", "KONG_VAR")
+
+def snappy_repositories():
+    maybe(
+        new_git_repository,
+        name = "snappy",
+        branch = KONG_VAR["SNAPPY"],
+        remote = "https://github.com/google/snappy",
+        visibility = ["//visibility:public"],  # let this to be referenced by openresty build
+        build_file = "//build/openresty/snappy:BUILD.bazel",
+    )

changelog/unreleased/kong/cp-dp-rpc.yml

@@ -0,0 +1,3 @@
+message: "Remote procedure call (RPC) framework for Hybrid mode deployments."
+type: feature
+scope: Clustering

changelog/unreleased/kong/dynamic-log-level-rpc.yml

@@ -0,0 +1,6 @@
+message: |
+  Dynamic log level over Hybrid mode RPC which allows setting DP log level
+  to a different level for specified duration before reverting back
+  to the `kong.conf` configured value.
+type: feature
+scope: Clustering

kong-3.7.0-0.rockspec

@@ -59,6 +59,7 @@ dependencies = {
   "lpeg == 1.1.0",
   "lua-resty-ljsonschema == 1.1.6-2",
   "lua-resty-jq == 0.1.0",
+  "lua-resty-snappy == 1.0-1",
 }
 build = {
   type = "builtin",
@@ -106,6 +107,16 @@ build = {
     ["kong.clustering.config_sync_backup.election"] = "kong/clustering/config_sync_backup/election.lua",
     ["kong.clustering.config_sync_backup.strategies.s3"] = "kong/clustering/config_sync_backup/strategies/s3.lua",
     ["kong.clustering.config_sync_backup.strategies.gcs"] = "kong/clustering/config_sync_backup/strategies/gcs.lua",
+    ["kong.clustering.services.debug"] = "kong/clustering/services/debug.lua",
+
+    ["kong.clustering.rpc.callbacks"] = "kong/clustering/rpc/callbacks.lua",
+    ["kong.clustering.rpc.future"] = "kong/clustering/rpc/future.lua",
+    ["kong.clustering.rpc.json_rpc_v2"] = "kong/clustering/rpc/json_rpc_v2.lua",
+    ["kong.clustering.rpc.manager"] = "kong/clustering/rpc/manager.lua",
+    ["kong.clustering.rpc.queue"] = "kong/clustering/rpc/queue.lua",
+    ["kong.clustering.rpc.socket"] = "kong/clustering/rpc/socket.lua",
+    ["kong.clustering.rpc.utils"] = "kong/clustering/rpc/utils.lua",
+    ["kong.clustering.rpc.concentrator"] = "kong/clustering/rpc/concentrator.lua",
 
     ["kong.cluster_events"] = "kong/cluster_events/init.lua",
     ["kong.cluster_events.strategies.postgres"] = "kong/cluster_events/strategies/postgres.lua",
@@ -552,6 +563,7 @@ build = {
     ["kong.db.migrations.core.020_330_to_340"] = "kong/db/migrations/core/020_330_to_340.lua",
     ["kong.db.migrations.core.021_340_to_350"] = "kong/db/migrations/core/021_340_to_350.lua",
     ["kong.db.migrations.core.022_350_to_360"] = "kong/db/migrations/core/022_350_to_360.lua",
+    ["kong.db.migrations.core.023_360_to_370"] = "kong/db/migrations/core/023_360_to_370.lua",
     ["kong.db.migrations.operations.200_to_210"] = "kong/db/migrations/operations/200_to_210.lua",
     ["kong.db.migrations.operations.212_to_213"] = "kong/db/migrations/operations/212_to_213.lua",
     ["kong.db.migrations.operations.230_to_260"] = "kong/db/migrations/operations/230_to_260.lua",

kong/api/routes/debug.lua

@@ -23,6 +23,7 @@ local kong                               = kong
 local pcall                              = pcall
 local type                               = type
 local tostring                           = tostring
+local tonumber                           = tonumber
 local string_format                      = string.format
 local math_max                           = math.max
 local math_random                        = math.random
@@ -443,4 +444,49 @@ routes[cluster_name] = {
   end
 }
 
+
+if kong.rpc then
+  routes["/clustering/data-planes/:node_id/log-level"] = {
+    GET = function(self)
+      local res, err =
+        kong.rpc:call(self.params.node_id, "kong.debug.log_level.v1.get_log_level")
+      if not res then
+        return kong.response.exit(500, { message = err, })
+      end
+
+      return kong.response.exit(200, res)
+    end,
+    PUT = function(self)
+      local new_level = self.params.current_level
+      local timeout = self.params.timeout and
+                      math.ceil(tonumber(self.params.timeout)) or nil
+
+      if not new_level then
+        return kong.response.exit(400, { message = "Required parameter \"current_level\" is missing.", })
+      end
+
+      local res, err = kong.rpc:call(self.params.node_id,
+                                     "kong.debug.log_level.v1.set_log_level",
+                                     new_level,
+                                     timeout)
+      if not res then
+        return kong.response.exit(500, { message = err, })
+      end
+
+      return kong.response.exit(201)
+    end,
+    DELETE = function(self)
+      local res, err = kong.rpc:call(self.params.node_id,
+                                     "kong.debug.log_level.v1.set_log_level",
+                                     "warn",
+                                     0)
+      if not res then
+        return kong.response.exit(500, { message = err, })
+      end
+
+      return kong.response.exit(204)
+    end,
+  }
+end
+
 return routes

kong/clustering/control_plane.lua

@@ -261,6 +261,12 @@ function _M:handle_cp_websocket(cert)
   local sync_status = CLUSTERING_SYNC_STATUS.UNKNOWN
   local purge_delay = self.conf.cluster_data_plane_purge_delay
   local update_sync_status = function()
+    local rpc_peers
+
+    if self.conf.cluster_rpc then
+      rpc_peers = kong.rpc:get_peers()
+    end
+
     local ok
     ok, err = kong.db.clustering_data_planes:upsert({ id = dp_id }, {
       last_seen = last_seen,
@@ -273,6 +279,8 @@ function _M:handle_cp_websocket(cert)
       sync_status = sync_status, -- TODO: import may have been failed though
       labels = data.labels,
       cert_details = dp_cert_details,
+      -- only update rpc_capabilities if dp_id is connected
+      rpc_capabilities = rpc_peers and rpc_peers[dp_id] or {},
     }, { ttl = purge_delay })
     if not ok then
       ngx_log(ngx_ERR, _log_prefix, "unable to update clustering data plane status: ", err, log_suffix)