Redis系列七 调试Lua

劳而不伐，有功而不德，厚之至也。（《周易·系辞上》）

调试redis+lua

学了lua的基本语法，了解了redis+lua的配套用法，但是却不知道怎么断点调试。学就学全面点， 官网中有dubug相关说明。地址：Redis Lua scripts debugger

基础

-- script.lua
local ping = redis.call('ping')
return ping

# 执行脚本 --ldb --eval
➜  7Debug git:(main) ✗ redis-cli --ldb --eval /Users/mw/Desktop/Github/Integration/Redis/7Debug/script.lua
Lua debugging session started, please use:
quit    -- End the session.
restart -- Restart the script in debug mode again.
help    -- Show Lua script debugging commands.

* Stopped at 1, stop reason = step over
# 调试位置
-> 1   local ping = redis.call('ping')
# next
lua debugger> n
<redis> ping
<reply> "+PONG"
* Stopped at 2, stop reason = step over
# 调试位置
-> 2   return ping
# 打印lua变量
lua debugger> print ping
<value> {["ok"]="PONG"}
# next
lua debugger> n
# lua返回的结果
PONG
# 调试结束
(Lua debugging session ended -- dataset changes rolled back)
# 退出redis-cli
127.0.0.1:6379> exit
➜  7Debug git:(main) ✗

-- script1.lua
-- 测试接受参数
local src = KEYS[1]
local dst = KEYS[2]

local count = tonumber(ARGV[1])

参数

KEYS & ARGV

传递参数时<KEYS & ARGV>的注意事项

# 传参数: list_a list_b 10
➜  7Debug git:(main) ✗ redis-cli --ldb --eval /Users/mw/Desktop/Github/Integration/Redis/7Debug/script1.lua list_a list_b 10
Lua debugging session started, please use:
quit    -- End the session.
restart -- Restart the script in debug mode again.
help    -- Show Lua script debugging commands.

* Stopped at 1, stop reason = step over
-> 1   local src = KEYS[1]
# 
lua debugger> print
No local variables in the current context.
# 
lua debugger> n
* Stopped at 2, stop reason = step over
-> 2   local dst = KEYS[2]
# 
lua debugger> n
* Stopped at 3, stop reason = step over
-> 3   local count = tonumber(ARGV[1])
# 打印 KEYS 全部都是keys
lua debugger> print KEYS
<value> {"list_a"; "list_b"; "10"}
# 打印 ARGV
lua debugger> print ARGV
<value> {}
# 结束
lua debugger> n

(integer) 1

(Lua debugging session ended -- dataset changes rolled back)

127.0.0.1:6379>

参数 中 KEYS & ARGV 区分: 逗号隔开

1. 参数list_b,, 逗号与key之间没有空格，则认为依旧是KEYS；

# 注意 
➜  7Debug git:(main) ✗ redis-cli --ldb --eval /Users/mw/Desktop/Github/Integration/Redis/7Debug/script1.lua list_a list_b , 10
Lua debugging session started, please use:
quit    -- End the session.
restart -- Restart the script in debug mode again.
help    -- Show Lua script debugging commands.

* Stopped at 1, stop reason = step over
-> 1   local src = KEYS[1]
# KEYS
lua debugger> print KEYS
<value> {"list_a"; "list_b"}
# ARGV
lua debugger> print ARGV
<value> {"10"}
lua debugger> 
lua debugger> n
* Stopped at 2, stop reason = step over
-> 2   local dst = KEYS[2]
lua debugger> n
* Stopped at 3, stop reason = step over
-> 3   local count = tonumber(ARGV[1])
lua debugger> n
* Stopped at 4, stop reason = step over
-> 4   return true
#
lua debugger> print
<value> src = "list_a"
<value> dst = "list_b"
<value> count = 10
lua debugger> n

(integer) 1

(Lua debugging session ended -- dataset changes rolled back)

127.0.0.1:6379>

队列操作

将list_a中的一个元素push到list_b

➜  7Debug git:(main) ✗ redis-cli --ldb --eval /Users/mw/Desktop/Github/Integration/Redis/7Debug/script1.lua list_a list_b , 10
Lua debugging session started, please use:
quit    -- End the session.
restart -- Restart the script in debug mode again.
help    -- Show Lua script debugging commands.

* Stopped at 1, stop reason = step over
-> 1   local src = KEYS[1]
# 打印keys
lua debugger> print KEYS
<value> {"list_a"; "list_b"}
# 打印参数
lua debugger> print ARGV
<value> {"10"}
# 初始化队列 list_a、list_b
lua debugger> r lpush list_a 1 2 3 4 
<redis> lpush list_a 1 2 3 4
<reply> 4
lua debugger> r lpush list_b a b c d
<redis> lpush list_b a b c d
<reply> 4
lua debugger> n
* Stopped at 2, stop reason = step over
-> 2   local dst = KEYS[2]
lua debugger> n
* Stopped at 3, stop reason = step over
-> 3   local count = tonumber(ARGV[1])
lua debugger> n
* Stopped at 5, stop reason = step over
-> 5   local item = redis.call('rpop', src)
# next 执行pop
lua debugger> n
<redis> rpop list_a
<reply> "1"
* Stopped at 6, stop reason = step over
-> 6   redis.call('lpush', dst, item)
# next 执行push
lua debugger> n
<redis> lpush list_b 1
<reply> 5
* Stopped at 7, stop reason = step over
-> 7   return true
# r: redis; 获取list元素
lua debugger> r lrange list_a 0 -1
<redis> lrange list_a 0 -1
<reply> ["4","3","2"]
# r: redis; 获取list元素
lua debugger> r lrange list_b 0 -1
<redis> lrange list_b 0 -1
# 执行成功
<reply> ["1","d","c","b","a"]
# 重启，将所有执行回滚
lua debugger> restart

Lua debugging session started, please use:
quit    -- End the session.
restart -- Restart the script in debug mode again.
help    -- Show Lua script debugging commands.

* Stopped at 1, stop reason = step over
-> 1   local src = KEYS[1]
# 回滚至无数据
lua debugger> r lrange list_b 0 -1
<redis> lrange list_b 0 -1
<reply> []
lua debugger>

断点调试

断点操作

# 写入redis 准备数据
➜  7Debug git:(main) ✗ redis-cli
127.0.0.1:6379> lpush list_a 1 2 3 4
(integer) 4
127.0.0.1:6379> lpush list_b a b c d
(integer) 4
127.0.0.1:6379> llen list_a
(integer) 4
127.0.0.1:6379> llen list_b
(integer) 4
127.0.0.1:6379>

# 获取全部文件
lua debugger> w
   1   local src = KEYS[1]
   2   local dst = KEYS[2]
   3   local count = tonumber(ARGV[1])
   4   
-> 5   while count < 10 do
   6       local item = redis.call('rpop', src)
   7       if item == false then break end
   8       redis.call('lpush', dst, item)
   9       count = count -1
   10  end
   11  
   12  return redis.call('llen', dst);
# 显示第7行 【l:list】
lua debugger> l 7
   2   local dst = KEYS[2]
   3   local count = tonumber(ARGV[1])
   4   
-> 5   while count < 10 do
   6       local item = redis.call('rpop', src)
   7       if item == false then break end
   8       redis.call('lpush', dst, item)
   9       count = count -1
   10  end
   11  
   12  return redis.call('llen', dst);
# 显示第7行前后一行 【l:list】
lua debugger> l 7 1
   6       local item = redis.call('rpop', src)
   7       if item == false then break end
   8       redis.call('lpush', dst, item)
lua debugger> b 6
-> 5   while count < 10 do
  #6       local item = redis.call('rpop', src)
   7       if item == false then break end
# continue 继续，直到断点执行
lua debugger> c

(integer) 4

(Lua debugging session ended -- dataset changes rolled back)

127.0.0.1:6379>

逐步断点

lua debugger> w
-> 1   local src = KEYS[1]
   2   local dst = KEYS[2]
   3   local count = tonumber(ARGV[1])
   4   
   5   while count > 0 do
   6       local item = redis.call('rpop', src)
   7       if item == false then break end
   8       redis.call('lpush', dst, item)
   9       count = count -1
   10  end
   11  
   12  return redis.call('llen', dst);
lua debugger> b 8
   7       if item == false then break end
  #8       redis.call('lpush', dst, item)
   9       count = count -1
# 验证断点位置
lua debugger> w
-> 1   local src = KEYS[1]
   2   local dst = KEYS[2]
   3   local count = tonumber(ARGV[1])
   4   
   5   while count > 0 do
   6       local item = redis.call('rpop', src)
   7       if item == false then break end
  #8       redis.call('lpush', dst, item)
   9       count = count -1
   10  end
   11  
   12  return redis.call('llen', dst);
# 等同与next
lua debugger> c
* Stopped at 8, stop reason = break point
->#8       redis.call('lpush', dst, item)

lua debugger> print
<value> src = "list_a"
<value> dst = "list_b"
<value> count = 10
<value> item = "1"
lua debugger> c
* Stopped at 8, stop reason = break point
->#8       redis.call('lpush', dst, item)
lua debugger> c
* Stopped at 8, stop reason = break point
->#8       redis.call('lpush', dst, item)
lua debugger> c
* Stopped at 8, stop reason = break point
->#8       redis.call('lpush', dst, item)
# 打印日志
lua debugger> print
<value> src = "list_a"
<value> dst = "list_b"
<value> count = 7
<value> item = "4"

redis.debug 一步到位

此处有加新代码：redis.debug('dubug value:', item)

lua debugger> w
-> 1   local src = KEYS[1]
   2   local dst = KEYS[2]
   3   local count = tonumber(ARGV[1])
   4   
   5   while count > 0 do
   6       local item = redis.call('rpop', src)
# 采用redis.debug
   7       redis.debug('dubug value:', item)
   8       if item == false then break end
   9       redis.call('lpush', dst, item)
   10      count = count -1
   11  end
   12  
   13  return redis.call('llen', dst);
# 继续，打印redis.debug处的日志
lua debugger> c
<debug> line 7: "dubug value:", "1"
<debug> line 7: "dubug value:", "2"
<debug> line 7: "dubug value:", "3"
<debug> line 7: "dubug value:", "4"
<debug> line 7: "dubug value:", false

(integer) 8

(Lua debugging session ended -- dataset changes rolled back)

127.0.0.1:6379>