feat(core): add lmdb validation tag directive

.requirements

@@ -7,7 +7,7 @@ PCRE=8.45
 LIBEXPAT=2.5.0
 
 LUA_KONG_NGINX_MODULE=4fbc3ddc7dcbc706ed286b95344f3cb6da17e637 # 0.8.0
-LUA_RESTY_LMDB=d236fc5ba339897e8f2c6ada1c1b4ab9311feee8 # 1.4.0
+LUA_RESTY_LMDB=19a6da0616db43baf8197dace59e64244430b3c4 # 1.4.1
 LUA_RESTY_EVENTS=8448a92cec36ac04ea522e78f6496ba03c9b1fd8 # 0.2.0
 LUA_RESTY_WEBSOCKET=60eafc3d7153bceb16e6327074e0afc3d94b1316 # 0.4.0
 ATC_ROUTER=7a2ad42d4246598ba1f753b6ae79cb1456040afa # 1.3.1

changelog/unreleased/kong/bump-lua-resty-lmdb-1.4.1.yml

@@ -0,0 +1,3 @@
+message: Bumped lua-resty-lmdb from 1.3.0 to 1.4.1
+type: dependency
+scope: Core

changelog/unreleased/kong/introduce_lmdb_validation_tag.yml

@@ -0,0 +1,6 @@
+message: |
+  Validate LMDB cache by Kong's version (major + minor),
+  wiping the content if tag mismatch to avoid compatibility issues
+  during minor version upgrade.
+type: feature
+scope: Configuration

kong/conf_loader/init.lua

@@ -1,6 +1,7 @@
 local require = require
 
 
+local kong_meta = require "kong.meta"
 local kong_default_conf = require "kong.templates.kong_defaults"
 local process_secrets = require "kong.cmd.utils.process_secrets"
 local nginx_signals = require "kong.cmd.utils.nginx_signals"
@@ -683,6 +684,12 @@ local _nop_tostring_mt = {
 }
 
 
+-- using kong version, "major.minor"
+local LMDB_VALIDATION_TAG = string.format("%d.%d",
+                                          kong_meta._VERSION_TABLE.major,
+                                          kong_meta._VERSION_TABLE.minor)
+
+
 local function parse_value(value, typ)
   if type(value) == "string" then
     value = strip(value)
@@ -2002,6 +2009,9 @@ local function load(path, custom_conf, opts)
     end
   end
 
+  -- lmdb validation tag
+  conf.lmdb_validation_tag = LMDB_VALIDATION_TAG
+
   -- Wasm module support
   if conf.wasm then
     local wasm_filters = get_wasm_filters(conf.wasm_filters_path)

kong/templates/nginx_inject.lua

@@ -2,5 +2,10 @@ return [[
 > if database == "off" then
 lmdb_environment_path ${{LMDB_ENVIRONMENT_PATH}};
 lmdb_map_size         ${{LMDB_MAP_SIZE}};
+
+> if lmdb_validation_tag then
+lmdb_validation_tag   $(lmdb_validation_tag);
+> end
+
 > end
 ]]

spec/01-unit/03-conf_loader_spec.lua

@@ -67,6 +67,7 @@ describe("Configuration loader", function()
     assert.same(nil, conf.privileged_agent)
     assert.same(true, conf.dedicated_config_processing)
     assert.same(false, conf.allow_debug_header)
+    assert.matches("%d+%.%d+", conf.lmdb_validation_tag)
     assert.is_nil(getmetatable(conf))
   end)
   it("loads a given file, with higher precedence", function()
@@ -84,6 +85,7 @@ describe("Configuration loader", function()
     assert.same({"127.0.0.1:9001"}, conf.admin_listen)
     assert.same({"0.0.0.0:9000", "0.0.0.0:9443 http2 ssl",
                  "0.0.0.0:9002 http2"}, conf.proxy_listen)
+    assert.matches("%d+%.%d+", conf.lmdb_validation_tag)
     assert.is_nil(getmetatable(conf))
   end)
   it("preserves default properties if not in given file", function()

spec/01-unit/04-prefix_handler_spec.lua

@@ -1415,6 +1415,7 @@ describe("NGINX conf compiler", function()
       local main_inject_conf = prefix_handler.compile_nginx_main_inject_conf(helpers.test_conf)
       assert.not_matches("lmdb_environment_path", main_inject_conf, nil, true)
       assert.not_matches("lmdb_map_size", main_inject_conf, nil, true)
+      assert.not_matches("lmdb_validation_tag", main_inject_conf, nil, true)
     end)
 
     it("compiles a main NGINX inject conf #database=off", function()
@@ -1424,6 +1425,7 @@ describe("NGINX conf compiler", function()
       local main_inject_conf = prefix_handler.compile_nginx_main_inject_conf(conf)
       assert.matches("lmdb_environment_path%s+dbless.lmdb;", main_inject_conf)
       assert.matches("lmdb_map_size%s+2048m;", main_inject_conf)
+      assert.matches("lmdb_validation_tag%s+%d+%.%d+;", main_inject_conf)
     end)
   end)
 

spec/fixtures/custom_nginx.template

@@ -16,6 +16,11 @@ $(el.name) $(el.value);
 > if database == "off" then
 lmdb_environment_path ${{LMDB_ENVIRONMENT_PATH}};
 lmdb_map_size         ${{LMDB_MAP_SIZE}};
+
+> if lmdb_validation_tag then
+lmdb_validation_tag   $(lmdb_validation_tag);
+> end
+
 > end
 
 events {