t/core/lrucache2.t - apisix - Git at Google

 #
 # Licensed to the Apache Software Foundation (ASF) under one or more
 # contributor license agreements.  See the NOTICE file distributed with
 # this work for additional information regarding copyright ownership.
 # The ASF licenses this file to You under the Apache License, Version 2.0
 # (the "License"); you may not use this file except in compliance with
 # the License.  You may obtain a copy of the License at
 #
 #     http://www.apache.org/licenses/LICENSE-2.0
 #
 # Unless required by applicable law or agreed to in writing, software
 # distributed under the License is distributed on an "AS IS" BASIS,
 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 # See the License for the specific language governing permissions and
 # limitations under the License.
 #
 use t::APISIX 'no_plan';

 repeat_each(1);
 no_long_string();
 no_root_location();
 log_level("info");

 run_tests;

 __DATA__

 === TEST 1: negative cache basic functionality
 --- config
     location /t {
         content_by_lua_block {
             local core = require("apisix.core")

             local call_count = 0
             local function create_obj_fail()
                 call_count = call_count + 1
                 return nil, "simulated failure"
             end

             -- create LRU cache with negative caching
             local lru_get = core.lrucache.new({
                 ttl = 1,
                 count = 256,
                 neg_ttl = 0.5,  -- shorter TTL for failures
                 neg_count = 128
             })

             -- First call should execute the function and cache the failure
             local obj, err = lru_get("fail_key", "v1", create_obj_fail)
             ngx.say("call_count after first call: ", call_count)
             ngx.say("first call result: obj=", tostring(obj), ", err=", tostring(err))

             -- Second call should return from negative cache without calling create_obj_fail
             obj, err = lru_get("fail_key", "v1", create_obj_fail)
             ngx.say("call_count after second call: ", call_count)
             ngx.say("second call result: obj=", tostring(obj), ", err=", tostring(err))

             -- Different version should bypass negative cache
             obj, err = lru_get("fail_key", "v2", create_obj_fail)
             ngx.say("call_count after different version: ", call_count)
             ngx.say("different version result: obj=", tostring(obj), ", err=", tostring(err))
         }
     }
 --- request
 GET /t
 --- response_body
 call_count after first call: 1
 first call result: obj=nil, err=simulated failure
 call_count after second call: 1
 second call result: obj=nil, err=simulated failure
 call_count after different version: 2
 different version result: obj=nil, err=simulated failure


 === TEST 2: negative cache TTL expiration
 --- config
     location /t {
         content_by_lua_block {
             local core = require("apisix.core")

             local call_count = 0
             local function create_obj_fail()
                 call_count = call_count + 1
                 return nil, "simulated failure"
             end

             -- Create LRU cache with very short negative TTL
             local lru_get = core.lrucache.new({
                 ttl = 10,
                 count = 256,
                 neg_ttl = 0.1,  -- very short TTL for failures
                 neg_count = 128
             })

             -- First call
             local obj, err = lru_get("fail_key", "v1", create_obj_fail)
             ngx.say("call_count after first call: ", call_count)

             -- Immediate second call - should use negative cache
             obj, err = lru_get("fail_key", "v1", create_obj_fail)
             ngx.say("call_count after immediate call: ", call_count)

             -- Wait for negative cache to expire
             ngx.sleep(0.15)

             -- This should call create_obj_fail again
             obj, err = lru_get("fail_key", "v1", create_obj_fail)
             ngx.say("call_count after TTL expiration: ", call_count)
         }
     }
 --- request
 GET /t
 --- response_body
 call_count after first call: 1
 call_count after immediate call: 1
 call_count after TTL expiration: 2


 === TEST 3: mixed success and failure caching
 --- config
     location /t {
         content_by_lua_block {
             local core = require("apisix.core")

             local success_count = 0
             local fail_count = 0

             local function create_obj_success()
                 success_count = success_count + 1
                 return {value = "success_" .. success_count}
             end

             local function create_obj_fail()
                 fail_count = fail_count + 1
                 return nil, "failure_" .. fail_count
             end

             local lru_get = core.lrucache.new({
                 ttl = 1,
                 count = 256,
                 neg_ttl = 0.5,
                 neg_count = 128
             })

             -- Test success caching
             local obj1 = lru_get("success_key", "v1", create_obj_success)
             ngx.say("success_count after first success: ", success_count)
             ngx.say("success value: ", obj1.value)

             local obj2 = lru_get("success_key", "v1", create_obj_success)
             ngx.say("success_count after cached success: ", success_count)
             ngx.say("cached success value: ", obj2.value)

             -- Test failure caching
             local obj3, err3 = lru_get("fail_key", "v1", create_obj_fail)
             ngx.say("fail_count after first failure: ", fail_count)
             ngx.say("failure error: ", err3)

             local obj4, err4 = lru_get("fail_key", "v1", create_obj_fail)
             ngx.say("fail_count after cached failure: ", fail_count)
             ngx.say("cached failure error: ", err4)
         }
     }
 --- request
 GET /t
 --- response_body
 success_count after first success: 1
 success value: success_1
 success_count after cached success: 1
 cached success value: success_1
 fail_count after first failure: 1
 failure error: failure_1
 fail_count after cached failure: 1
 cached failure error: failure_1


 === TEST 4: negative cache with different keys
 --- config
     location /t {
         content_by_lua_block {
             local core = require("apisix.core")

             local call_count = 0
             local function create_obj_fail(key)
                 call_count = call_count + 1
                 return nil, "failed for " .. key
             end

             local lru_get = core.lrucache.new({
                 ttl = 1,
                 count = 256,
                 neg_ttl = 0.5,
                 neg_count = 128
             })

             -- First key
             local obj1, err1 = lru_get("key1", "v1", create_obj_fail, "key1")
             ngx.say("call_count after key1: ", call_count)

             -- Second key
             local obj2, err2 = lru_get("key2", "v1", create_obj_fail, "key2")
             ngx.say("call_count after key2: ", call_count)

             -- Repeat key1 - should use negative cache
             local obj3, err3 = lru_get("key1", "v1", create_obj_fail, "key1")
             ngx.say("call_count after key1 repeat: ", call_count)
             ngx.say("key1 error: ", err3)

             -- Repeat key2 - should use negative cache
             local obj4, err4 = lru_get("key2", "v1", create_obj_fail, "key2")
             ngx.say("call_count after key2 repeat: ", call_count)
             ngx.say("key2 error: ", err4)
         }
     }
 --- request
 GET /t
 --- response_body
 call_count after key1: 1
 call_count after key2: 2
 call_count after key1 repeat: 2
 key1 error: failed for key1
 call_count after key2 repeat: 2
 key2 error: failed for key2


 === TEST 5: negative cache respects version changes
 --- config
     location /t {
         content_by_lua_block {
             local core = require("apisix.core")

             local call_count = 0
             local function create_obj_fail(version)
                 call_count = call_count + 1
                 return nil, "failed for version " .. version
             end

             local lru_get = core.lrucache.new({
                 ttl = 10,
                 count = 256,
                 neg_ttl = 10,
                 neg_count = 128
             })

             -- Call with version 1
             local obj1, err1 = lru_get("version_key", "v1", create_obj_fail, "v1")
             ngx.say("call_count after v1: ", call_count)

             -- Call with version 1 again - should use negative cache
             local obj2, err2 = lru_get("version_key", "v1", create_obj_fail, "v1")
             ngx.say("call_count after v1 repeat: ", call_count)

             -- Call with version 2 - should bypass negative cache
             local obj3, err3 = lru_get("version_key", "v2", create_obj_fail, "v2")
             ngx.say("call_count after v2: ", call_count)

             -- Call with version 2 again - should use negative cache
             local obj4, err4 = lru_get("version_key", "v2", create_obj_fail, "v2")
             ngx.say("call_count after v2 repeat: ", call_count)
         }
     }
 --- request
 GET /t
 --- response_body
 call_count after v1: 1
 call_count after v1 repeat: 1
 call_count after v2: 2
 call_count after v2 repeat: 2
	#
	# Licensed to the Apache Software Foundation (ASF) under one or more
	# contributor license agreements. See the NOTICE file distributed with
	# this work for additional information regarding copyright ownership.
	# The ASF licenses this file to You under the Apache License, Version 2.0
	# (the "License"); you may not use this file except in compliance with
	# the License. You may obtain a copy of the License at
	#
	# http://www.apache.org/licenses/LICENSE-2.0
	#
	# Unless required by applicable law or agreed to in writing, software
	# distributed under the License is distributed on an "AS IS" BASIS,
	# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
	# See the License for the specific language governing permissions and
	# limitations under the License.
	#
	use t::APISIX 'no_plan';

	repeat_each(1);
	no_long_string();
	no_root_location();
	log_level("info");

	run_tests;

	__DATA__

	=== TEST 1: negative cache basic functionality
	--- config
	location /t {
	content_by_lua_block {
	local core = require("apisix.core")

	local call_count = 0
	local function create_obj_fail()
	call_count = call_count + 1
	return nil, "simulated failure"
	end

	-- create LRU cache with negative caching
	local lru_get = core.lrucache.new({
	ttl = 1,
	count = 256,
	neg_ttl = 0.5, -- shorter TTL for failures
	neg_count = 128
	})

	-- First call should execute the function and cache the failure
	local obj, err = lru_get("fail_key", "v1", create_obj_fail)
	ngx.say("call_count after first call: ", call_count)
	ngx.say("first call result: obj=", tostring(obj), ", err=", tostring(err))

	-- Second call should return from negative cache without calling create_obj_fail
	obj, err = lru_get("fail_key", "v1", create_obj_fail)
	ngx.say("call_count after second call: ", call_count)
	ngx.say("second call result: obj=", tostring(obj), ", err=", tostring(err))

	-- Different version should bypass negative cache
	obj, err = lru_get("fail_key", "v2", create_obj_fail)
	ngx.say("call_count after different version: ", call_count)
	ngx.say("different version result: obj=", tostring(obj), ", err=", tostring(err))
	}
	}
	--- request
	GET /t
	--- response_body
	call_count after first call: 1
	first call result: obj=nil, err=simulated failure
	call_count after second call: 1
	second call result: obj=nil, err=simulated failure
	call_count after different version: 2
	different version result: obj=nil, err=simulated failure



	=== TEST 2: negative cache TTL expiration
	--- config
	location /t {
	content_by_lua_block {
	local core = require("apisix.core")

	local call_count = 0
	local function create_obj_fail()
	call_count = call_count + 1
	return nil, "simulated failure"
	end

	-- Create LRU cache with very short negative TTL
	local lru_get = core.lrucache.new({
	ttl = 10,
	count = 256,
	neg_ttl = 0.1, -- very short TTL for failures
	neg_count = 128
	})

	-- First call
	local obj, err = lru_get("fail_key", "v1", create_obj_fail)
	ngx.say("call_count after first call: ", call_count)

	-- Immediate second call - should use negative cache
	obj, err = lru_get("fail_key", "v1", create_obj_fail)
	ngx.say("call_count after immediate call: ", call_count)

	-- Wait for negative cache to expire
	ngx.sleep(0.15)

	-- This should call create_obj_fail again
	obj, err = lru_get("fail_key", "v1", create_obj_fail)
	ngx.say("call_count after TTL expiration: ", call_count)
	}
	}
	--- request
	GET /t
	--- response_body
	call_count after first call: 1
	call_count after immediate call: 1
	call_count after TTL expiration: 2



	=== TEST 3: mixed success and failure caching
	--- config
	location /t {
	content_by_lua_block {
	local core = require("apisix.core")

	local success_count = 0
	local fail_count = 0

	local function create_obj_success()
	success_count = success_count + 1
	return {value = "success_" .. success_count}
	end

	local function create_obj_fail()
	fail_count = fail_count + 1
	return nil, "failure_" .. fail_count
	end

	local lru_get = core.lrucache.new({
	ttl = 1,
	count = 256,
	neg_ttl = 0.5,
	neg_count = 128
	})

	-- Test success caching
	local obj1 = lru_get("success_key", "v1", create_obj_success)
	ngx.say("success_count after first success: ", success_count)
	ngx.say("success value: ", obj1.value)

	local obj2 = lru_get("success_key", "v1", create_obj_success)
	ngx.say("success_count after cached success: ", success_count)
	ngx.say("cached success value: ", obj2.value)

	-- Test failure caching
	local obj3, err3 = lru_get("fail_key", "v1", create_obj_fail)
	ngx.say("fail_count after first failure: ", fail_count)
	ngx.say("failure error: ", err3)

	local obj4, err4 = lru_get("fail_key", "v1", create_obj_fail)
	ngx.say("fail_count after cached failure: ", fail_count)
	ngx.say("cached failure error: ", err4)
	}
	}
	--- request
	GET /t
	--- response_body
	success_count after first success: 1
	success value: success_1
	success_count after cached success: 1
	cached success value: success_1
	fail_count after first failure: 1
	failure error: failure_1
	fail_count after cached failure: 1
	cached failure error: failure_1



	=== TEST 4: negative cache with different keys
	--- config
	location /t {
	content_by_lua_block {
	local core = require("apisix.core")

	local call_count = 0
	local function create_obj_fail(key)
	call_count = call_count + 1
	return nil, "failed for " .. key
	end

	local lru_get = core.lrucache.new({
	ttl = 1,
	count = 256,
	neg_ttl = 0.5,
	neg_count = 128
	})

	-- First key
	local obj1, err1 = lru_get("key1", "v1", create_obj_fail, "key1")
	ngx.say("call_count after key1: ", call_count)

	-- Second key
	local obj2, err2 = lru_get("key2", "v1", create_obj_fail, "key2")
	ngx.say("call_count after key2: ", call_count)

	-- Repeat key1 - should use negative cache
	local obj3, err3 = lru_get("key1", "v1", create_obj_fail, "key1")
	ngx.say("call_count after key1 repeat: ", call_count)
	ngx.say("key1 error: ", err3)

	-- Repeat key2 - should use negative cache
	local obj4, err4 = lru_get("key2", "v1", create_obj_fail, "key2")
	ngx.say("call_count after key2 repeat: ", call_count)
	ngx.say("key2 error: ", err4)
	}
	}
	--- request
	GET /t
	--- response_body
	call_count after key1: 1
	call_count after key2: 2
	call_count after key1 repeat: 2
	key1 error: failed for key1
	call_count after key2 repeat: 2
	key2 error: failed for key2



	=== TEST 5: negative cache respects version changes
	--- config
	location /t {
	content_by_lua_block {
	local core = require("apisix.core")

	local call_count = 0
	local function create_obj_fail(version)
	call_count = call_count + 1
	return nil, "failed for version " .. version
	end

	local lru_get = core.lrucache.new({
	ttl = 10,
	count = 256,
	neg_ttl = 10,
	neg_count = 128
	})

	-- Call with version 1
	local obj1, err1 = lru_get("version_key", "v1", create_obj_fail, "v1")
	ngx.say("call_count after v1: ", call_count)

	-- Call with version 1 again - should use negative cache
	local obj2, err2 = lru_get("version_key", "v1", create_obj_fail, "v1")
	ngx.say("call_count after v1 repeat: ", call_count)

	-- Call with version 2 - should bypass negative cache
	local obj3, err3 = lru_get("version_key", "v2", create_obj_fail, "v2")
	ngx.say("call_count after v2: ", call_count)

	-- Call with version 2 again - should use negative cache
	local obj4, err4 = lru_get("version_key", "v2", create_obj_fail, "v2")
	ngx.say("call_count after v2 repeat: ", call_count)
	}
	}
	--- request
	GET /t
	--- response_body
	call_count after v1: 1
	call_count after v1 repeat: 1
	call_count after v2: 2
	call_count after v2 repeat: 2