Introduction 中文说明

TairString is a redis module developed and open sourced by the Alibaba Tair team, which mainly contains two functions:

• Enhance the function of redis string, and add two CAS/CAD commands
• The new data type exstrtype is added. Compared with the redis string, the version can be specified on its value, so that functions such as distributed locks can be easily implemented. At the same time, flags can be set on the value to support the memcached protocol.

Our modules

TairHash: A redis module, similar to redis hash, but you can set expire and version for the field
TairZset: A redis module, similar to redis zset, but you can set multiple scores for each member to support multi-dimensional sorting
TairString: A redis module, similar to redis string, but you can set expire and version for the value. It also provides many very useful commands, such as cas/cad, etc.

Quick start

127.0.0.1:6379> EXSET foo 100
OK
127.0.0.1:6379> EXGET foo
1) "100"
2) (integer) 1
127.0.0.1:6379> EXSET foo 200 VER 1
OK
127.0.0.1:6379> EXGET foo
1) "200"
2) (integer) 2
127.0.0.1:6379> EXSET foo 300 VER 1
(error) ERR update version is stale
127.0.0.1:6379> EXINCRBY foo 100
(integer) 300
127.0.0.1:6379> EXGET foo
1) "300"
2) (integer) 3
127.0.0.1:6379> EXSETVER foo 100
(integer) 1
127.0.0.1:6379> EXGET foo
1) "300"
2) (integer) 100
127.0.0.1:6379> EXCAS foo 400 100
1) OK
2)
3) (integer) 101
127.0.0.1:6379> EXGET foo
1) "400"
2) (integer) 101
127.0.0.1:6379> EXCAD foo 101
(integer) 1
127.0.0.1:6379> EXGET foo
(nil)

Docker

docker run -p 6379:6379 tairmodule/tairstring:latest

CAS/CAD - Redis string enhancement

CAS

Grammar and complexity：

CAS [EX seconds][exat timestamp] [PX milliseconds][pxat timestamp]
time complexity: O(1)

Command description:

CAS（Compare And Set），Set its value to newvalue when the current value of the string corresponding to key is equal to oldvalue

Parameter Description:

key: The key used to locate the string
oldvalue: Only when the current value of string and oldvalue are equal can its value be modified
newvalue：Set the value to newvalue when the current value of string and oldvalue are equal
EX：Relative expiration time in seconds
EXAT：Absolute expiration time in seconds
PX：Relative expiration time in milliseconds
PXAT：Millisecond absolute expiration time

Return value：

Type：Long
Returns 1 if the value is successfully updated, -1 if the key does not exist, and 0 if the value fails to be updated

Usage example：

127.0.0.1:6379> SET foo bar
OK
127.0.0.1:6379> CAS foo baa bzz
(integer) 0
127.0.0.1:6379> GET foo
"bar"
127.0.0.1:6379> CAS foo bar bzz
(integer) 1
127.0.0.1:6379> GET foo
"bzz"
127.0.0.1:6379> CAS foo bzz too EX 10
(integer) 1
127.0.0.1:6379> GET foo
"too"
127.0.0.1:6379> debug sleep 10
OK
(10.00s)
127.0.0.1:6379> GET foo
(nil)
127.0.0.1:6379>

CAD

Grammar and complexity：

CAD <key> <value>
time complexity: O(1)

Command description：

CAD（Compare And Delete），Delete the Key when the value is equal to the value in the engine

Parameter Description：

key: The key used to locate the string
value: Delete only when the current value of string and value are equal

Return value：

Type：Long
Return 1 if the key is successfully deleted, -1 if the key does not exist, and 0 if the key is deleted

Usage example：

127.0.0.1:6379> SET foo bar
OK
127.0.0.1:6379> CAD foo bzz
(integer) 0
127.0.0.1:6379> CAD not-exists xxx
(integer) -1
127.0.0.1:6379> CAD foo bar
(integer) 1
127.0.0.1:6379> GET foo
(nil)

exstrtype - A String with version and compatible memcached protocol

Command introduction

Command overview

Command	Grammar	Details
EXSET	EXSET <key> <value> [EX time][px time] [EXAT time][pxat time] [NX | XX][ver version | abs version] [FLAGS flags][withversion]	Save the value to the key. The meaning of each parameter is explained later
EXGET	EXGET <key> [WITHFLAGS]	Return the value and version of TairString
EXSETVER	EXSETVER <key> <version>	Set the version directly to a key, which is equivalent to EXSET ABS
EXINCRBY	EXINCRBY <key> <num> [EX time][px time] [EXAT time][exat time] [PXAT time][nx | xx] [VER version | ABS version][min minval] [MAX maxval][nonegative] [WITHVERSION]	Auto-increment or decrement the Key
EXINCRBYFLOAT	EXINCRBYFLOAT <key> <num> [EX time][px time] [EXAT time][exat time] [PXAT time][nx | xx] [VER version | ABS version][min minval] [MAX maxval]	Do the increment and decrement operations on Key, and the range of num is double
EXCAS	EXCAS <key> <newvalue> <version> [EX time] [PX time] [EXAT time] [PXAT time] [KEEPTTL]	Specify version to update the value. The update is successful when the version in the engine is the same as the specified one. If it fails, the old value and version will be returned
EXCAD	EXCAD <key> <version>	Delete the Key when the specified version is equal to the version in the engine, otherwise it will fail
EXAPPEND	EXAPPEND <key> <value> [NX|XX][ver version | abs version]	Append string to key
EXPREPEND	EXPREPEND <key> <value> [NX|XX][ver version | abs version]	Perform string prepend operation on key
EXGAE	EXGAE <key> [EX time][px time] [EXAT time][pxat time]	GAE(Get And Expire),Return the value+version+flags of TairString, and set the expire of the key. This command will not increase version

EXSET

Grammar and complexity：

EXSET <key> <value> [EX time][px time] [EXAT time][exat time] [PXAT time][nx | xx] [VER version | ABS version][flags flags] [WITHVERSION]
time complexity：O(1)

Command description：

Save the value to the key

Parameter Description：

key: The key used to locate the string
value: The value of TairString to be set
EX：Relative expiration time in seconds
EXAT：Absolute expiration time in seconds
PX：Relative expiration time in milliseconds
PXAT：Millisecond absolute expiration time
NX：Write when data does not exist
XX：Write when data exists
VER：Version number, if the data exists, compare it with the version number of the existing data, if it is equal, write it, and add 1 to the version number; if it is not equal, return an error; if the data does not exist, ignore the incoming version number and write After the import is successful, the data version number becomes 1
ABS：Absolute version number, regardless of whether the data exists, overwrite the specified version number FLAGS：The type is uint32_t to support the memcached protocol. If UINT_MAX is exceeded, an error will be returned. The default value is 0 by default
WITHVERSION：Modify the return value to version instead of "OK"

Return value:

Type：String
Succuss return OK

Usage example:

127.0.0.1:6379> EXSET foo bar XX
(nil)
127.0.0.1:6379> EXSET foo bar NX
OK
127.0.0.1:6379> EXSET foo bar NX
(nil)
127.0.0.1:6379> EXGET foo
1) "bar"
2) (integer) 1
127.0.0.1:6379> EXSET foo bar1 VER 10
(error) ERR update version is stale
127.0.0.1:6379> EXSET foo bar1 VER 1
OK
127.0.0.1:6379> EXGET foo
1) "bar1"
2) (integer) 2
127.0.0.1:6379> EXSET foo bar2 ABS 100
OK
127.0.0.1:6379> EXGET foo
1) "bar2"
2) (integer) 100
127.0.0.1:6379>

EXGET

Grammar and complexity：

EXGET <key> [WITHFLAGS]
time complexity：O(1)

Command description：

return value + version

Parameter Description：

key: The key used to locate the string WITHFLAGS: return flags

Return value:

Type：List/List<byte[]>
Success：value+version

Usage example：

127.0.0.1:6379> EXSET foo bar ABS 100
OK
127.0.0.1:6379> EXGET foo
1) "bar"
2) (integer) 100
127.0.0.1:6379> DEL foo
(integer) 1
127.0.0.1:6379> EXGET foo
(nil)
127.0.0.1:6379>

EXSETVER

Grammar and complexity：

EXSETVER <key> <version>
time complexity：O(1)

Command description：

Set the version directly to a key, similar to EXSET ABS

Parameter Description：

key: The key used to locate the string
version: Version number

Return value：

Type：Long
Success：1

Usage example：

127.0.0.1:6379> EXSET foo bar
OK
127.0.0.1:6379> EXGET foo
1) "bar"
2) (integer) 1
127.0.0.1:6379> EXSETVER foo 2
(integer) 1
127.0.0.1:6379> EXGET foo
1) "bar"
2) (integer) 2
127.0.0.1:6379> EXSETVER not-exists 0
(integer) 0
127.0.0.1:6379>

EXINCRBY

Grammar and complexity：

EXINCRBY | EXINCRBY <key> <num> [EX time][px time] [EXAT time][exat time] [PXAT time][nx | xx] [VER version | ABS version][min minval] [MAX maxval][nonegative] [WITHVERSION] time complexity：O(1)

Command description：

Perform auto-increment and auto-decrement operations on Key, and the range of type is long

Parameter Description：

key: The key used to locate the string
value: Increments the number stored at key by value EX：Relative expiration time in seconds
EXAT：Absolute expiration time in seconds
PX：Relative expiration time in milliseconds
PXAT：Millisecond absolute expiration time
NX：Write when data does not exist
XX：Write when data exists
VER：Version number, if the data exists, compare it with the version number of the existing data, if it is equal, write it, and add 1 to the version number; if it is not equal, return an error; if the data does not exist, ignore the incoming version number and write After the import is successful, the data version number becomes 1
ABS：Absolute version number, regardless of whether the data exists, overwrite the specified version number FLAGS：The type is uint32_t to support the memcached protocol. If UINT_MAX is exceeded, an error will be returned. The default value is 0 by default
WITHVERSION：Modify the return value to version instead of "OK" MIN：The minimum value of TairString MAX：Maximum value of TairString NONEGATIVE：After setting, if the result of incrby is less than 0, set value to 0 WITHVERSION：return cur version number

Return value：

Type：Long
Success：return value

Usage example：

127.0.0.1:6379> EXINCRBY foo 100
(integer) 100
127.0.0.1:6379> EXINCRBY foo 100 MAX 150
(error) ERR increment or decrement would overflow
127.0.0.1:6379> FLUSHALL
OK
127.0.0.1:6379> EXINCRBY foo 100
(integer) 100
127.0.0.1:6379> EXINCRBY foo 100 MAX 150
(error) ERR increment or decrement would overflow
127.0.0.1:6379> EXINCRBY foo 100 MAX 300
(integer) 200
127.0.0.1:6379> EXINCRBY foo 100 MIN 500
(error) ERR increment or decrement would overflow
127.0.0.1:6379> EXINCRBY foo 100 MIN 500 MAX 100
(error) ERR min or max is specified, but not valid
127.0.0.1:6379> EXINCRBY foo 100 MIN 50
(integer) 300
127.0.0.1:6379>

EXINCRBYFLOAT

Grammar and complexity：

EXINCRBYFLOAT [EX time][px time] [EXAT time][exat time] [PXAT time][nx | xx] [VER version | ABS version][min minval] [MAX maxval]
time complexity：O(1)

Command description：

Perform auto-increment and auto-decrement operations on Key, and the range of type is double

Parameter Description：

key: The key used to locate the string
value: Increments the number stored at key by value EX：Relative expiration time in seconds
EXAT：Absolute expiration time in seconds
PX：Relative expiration time in milliseconds
PXAT：Millisecond absolute expiration time
NX：Write when data does not exist
XX：Write when data exists
VER：Version number, if the data exists, compare it with the version number of the existing data, if it is equal, write it, and add 1 to the version number; if it is not equal, return an error; if the data does not exist, ignore the incoming version number and write After the import is successful, the data version number becomes 1
ABS：Absolute version number, regardless of whether the data exists, overwrite the specified version number FLAGS：The type is uint32_t to support the memcached protocol. If UINT_MAX is exceeded, an error will be returned. The default value is 0 by default
WITHVERSION：Modify the return value to version instead of "OK" MIN：The minimum value of TairString MAX：Maximum value of TairString

Return value：

Type：Double
Success：return cur value

Usage example：

127.0.0.1:6379> EXSET foo 100
OK
127.0.0.1:6379> EXINCRBYFLOAT foo 10.123
"110.123"
127.0.0.1:6379> EXINCRBYFLOAT foo 20 MAX 100
(error) ERR increment or decrement would overflow
127.0.0.1:6379> EXINCRBYFLOAT foo 20 MIN 100
"130.123"
127.0.0.1:6379> EXGET foo
1) "130.123"
2) (integer) 3
127.0.0.1:6379>

EXCAS

Grammar and complexity：

EXCAS [EX time] [PX time] [EXAT time] [PXAT time] [KEEPTTL]
time complexity：O(1)

Command description：

CAS（Compare And Set

Return value：

Type：List/List<byte[]>
Success：["OK", "", version] failed：["Err", value, version]

Usage example：

127.0.0.1:6379> EXSET foo bar
OK
127.0.0.1:6379> EXCAS foo bzz 1
1) OK
2)
3) (integer) 2
127.0.0.1:6379> EXGET foo
1) "bzz"
2) (integer) 2
127.0.0.1:6379> EXCAS foo bee 1
1) ERR update version is stale  
2) "bzz"
3) (integer) 2
127.0.0.1:6379>

EXCAD

Grammar and complexity：

EXCAD
time complexity：O(1)

Command description：

CAD（Compare And Delete）

Return value：

Type：Long
Success：1
key not exists：-1
failed：0

Usage example：

127.0.0.1:6379> EXSET foo bar
OK
127.0.0.1:6379> EXGET foo
1) "bar"
2) (integer) 1
127.0.0.1:6379> EXCAD not-exists 1
(integer) -1
127.0.0.1:6379> EXCAD foo 0
(integer) 0
127.0.0.1:6379> EXCAD foo 1
(integer) 1
127.0.0.1:6379> EXGET foo
(nil)
127.0.0.1:6379>

EXAPPEND

Grammar and complexity：

EXAPPEND <key> <value> [NX|XX][ver version | abs version]
time complexity：O(1)

Command description：

Append string to key

Parameter Description：

key: The key used to locate the string
value: The string that will be appended NX：Write when data does not exist
XX：Write when data exists
VER：Version number, if the data exists, compare it with the version number of the existing data, if it is equal, write it, and add 1 to the version number; if it is not equal, return an error; if the data does not exist, ignore the incoming version number and write After the import is successful, the data version number becomes 1
ABS：Absolute version number, regardless of whether the data exists, overwrite the specified version number

Return value：

Type：Long
Success：cur version

Usage example：

127.0.0.1:6379> EXSET foo bar
OK
127.0.0.1:6379> EXCAS foo bzz 1
1) OK
2)
3) (integer) 2
127.0.0.1:6379> EXGET foo
1) "bzz"
2) (integer) 2
127.0.0.1:6379> EXCAS foo bee 1
1) ERR update version is stale   
2) "bzz"
3) (integer) 2
127.0.0.1:6379>

EXPREPEND

Grammar and complexity：

EXPREPEND <key> <value> [NX|XX][ver version | abs version]
time complexity：O(1)

Command description：

Perform string prepend operation on key

Parameter Description：

key: The key used to locate the string
value: The value of TairString to be append
NX：Write when data does not exist
XX：Write when data exists

Return value：

Type：Long
Success：cur version

Usage example：

127.0.0.1:6379> EXSET foo bar
OK
127.0.0.1:6379> EXCAS foo bzz 1
1) OK
2)
3) (integer) 2
127.0.0.1:6379> EXGET foo
1) "bzz"
2) (integer) 2
127.0.0.1:6379> EXCAS foo bee 1
1) ERR update version is stale  
2) "bzz"
3) (integer) 2
127.0.0.1:6379>

EXGAE

Grammar and complexity：

EXGAE <key> [EX time | EXAT time | PX time | PXAT time]
time complexity：O(1)

Command description：

GAE（Get And Expire）, This command will not increment version

Parameter Description：

key: The key used to locate the string
EX：Relative expiration time in seconds
EXAT：Absolute expiration time in seconds
PX：Relative expiration time in milliseconds
PXAT：Millisecond absolute expiration time

Return value：

Type：List<String>/List<byte[]>
Succuss return value+version+flags

Usage example:

127.0.0.1:6379> EXSET foo bar
OK
127.0.0.1:6379> EXCAS foo bzz 1
1) OK
2)
3) (integer) 2
127.0.0.1:6379> EXGET foo
1) "bzz"
2) (integer) 2
127.0.0.1:6379> EXCAS foo bee 1
1) ERR update version is stale  # Note that what is returned here is a simple string (returning error will cause Jedis to throw an exception)
2) "bzz"
3) (integer) 2
127.0.0.1:6379>

BUILD

mkdir build  
cd build  
cmake ../ && make -j

then the tairstring_module.so library file will be generated in the lib directory

./redis-server --loadmodule /path/to/tairstring_module.so

TEST

1. Modify the path in the tairstring.tcl file in the tests directory to set testmodule [file your_path/tairstring_module.so]
2. Add the path of the tairstring.tcl file in the tests directory to the all_tests of redis test_helper.tcl
3. run ./runtest --single tairstring

Client

language	GitHub
Java	https://github.com/alibaba/alibabacloud-tairjedis-sdk
Python	https://github.com/alibaba/tair-py
Go	https://github.com/alibaba/tair-go
.Net	https://github.com/alibaba/AlibabaCloud.TairSDK