Script Development / Simple Cache DFF.CACHE

DataFlux Func includes a built-in simple cache functionality DFF.CACHE based on Redis. For scenarios requiring data caching with relatively simple needs, this built-in cache can be used directly.

The storage follows a Scope-Key-Value structure. Keys with the same name are allowed under different namespaces.

Simple Cache Does Not Preserve Original Data Types

When operating the simple cache, regardless of whether a string or a number is written in the code, the value read back will always be a string.

Users need to handle the read content themselves, performing appropriate type conversion or deserialization.

General Methods

Methods related to the cache database itself and independent of specific Key types.

DFF.CACHE.ping()

Added in version 6.0.6

Ping to check the cache database response.

DFF.CACHE.ping()
# True

DFF.CACHE.info()

Added in version 6.0.6

Get cache database information.

DFF.CACHE.info()

DFF.CACHE.dbsize()

Added in version 6.0.6

Get the number of keys in the cache database.

DFF.CACHE.dbsize()
# 10

DFF.CACHE.type(...)

Added in version 6.0.6

Get the type of a Key. Parameters are as follows:

Parameter	Type	Required / Default	Description
key	str	Required	Key name
scope	str	Current script name	Namespace

DFF.CACHE.set('my_key', 100, scope='my_scope')
DFF.CACHE.type('my_key', scope='my_scope')
# 'string'

DFF.CACHE.keys(...)

Added in version 6.0.6

Get a list of keys. Parameters are as follows:

Parameter	Type	Required / Default	Description
pattern	str	"*"	Key name matching pattern Supports * wildcard
scope	str	Current script name	Namespace

DFF.CACHE.keys('*', scope='my_scope')
# ['my_key']

DFF.CACHE.exists(...)

Added in version 6.0.6

Check if a Key exists. Parameters are as follows:

Parameter	Type	Required / Default	Description
key	str	Required	Key name
scope	str	Current script name	Namespace

DFF.CACHE.exists('my_key', scope='my_scope')
# True

DFF.CACHE.expire(...)

Set the expiration time for a cache. Parameters are as follows:

Parameter	Type	Required / Default	Description
key	str	Required	Key name
expire	int	None	Expiration duration. Unit: seconds None means never expires
scope	str	Current script name	Namespace

DFF.CACHE.expire('my_key', 3600, scope='my_scope')

DFF.CACHE.expireat(...)

Added in version 6.0.6

Set the expiration timestamp for a cache. Parameters are as follows:

Parameter	Type	Required / Default	Description
key	str	Required	Key name
timestamp	int	Required	UNIX timestamp (unit: seconds)
scope	str	Current script name	Namespace

DFF.CACHE.expireat('my_key', int(time.time() + 3600), scope='my_scope')

DFF.CACHE.ttl(...)

Added in version 6.0.6

Get the remaining expiration time (seconds) for a key. Parameters are as follows:

Parameter	Type	Required / Default	Description
key	str	Required	Key name
scope	str	Current script name	Namespace

DFF.CACHE.ttl('my_key', scope='my_scope')
# 3599

DFF.CACHE.delete(...)

Delete stored data. Parameters are as follows:

Parameter	Type	Required / Default	Description
key	str	Required	Key name
scope	str	Current script name	Namespace

DFF.CACHE.delete('my_key', scope='my_scope')

DFF.CACHE.delete_pattern(...)

Delete stored data based on a key name matching pattern. Parameters are as follows:

Parameter	Type	Required / Default	Description
pattern	str	"*"	Key name matching pattern Supports * wildcard
scope	str	Current script name	Namespace

DFF.CACHE.set('my_key', 100, scope='my_scope')
DFF.CACHE.set('my_key2', 200, scope='my_scope')

DFF.CACHE.delete_pattern('my*', scope='my_scope')

String Methods

Methods for operating on values written via the DFF.CACHE.set(...) method.

DFF.CACHE.set(...)

Set cache. Parameters are as follows:

Parameter	Type	Required / Default	Description
key	str	Required	Key name
value	str / int / float	Required	Data
expires / expire	int	None	Expiration time. Unit: seconds None means never expires
not_exists	bool	False	Write only if the key does not exist
exists	bool	False	Write only if the key does exist
scope	str	Current script name	Namespace

DFF.CACHE.set('my_key', 100, scope='my_scope')

DFF.CACHE.mset(...)

Added in version 6.0.6

Batch set cache. Parameters are as follows:

Parameter	Type	Required / Default	Description
key_values	dict	Required	Key-value dictionary
scope	str	Current script name	Namespace

data = {
  'my_key' : 100,
  'my_key2': 200,
}
DFF.CACHE.mset(data, scope='my_scope')

DFF.CACHE.get(...)

Get cache. Parameters are as follows:

Parameter	Type	Required / Default	Description
key	str	Required	Key name
scope	str	Current script name	Namespace

DFF.CACHE.set('my_key', 100, scope='my_scope')

DFF.CACHE.get('my_key', scope='my_scope')
# '100'

DFF.CACHE.mget(...)

Added in version 6.0.6

Batch get cache. Parameters are as follows:

Parameter	Type	Required / Default	Description
keys	list	Required	List of key names
scope	str	Current script name	Namespace

DFF.CACHE.set('my_key', 100, scope='my_scope')
DFF.CACHE.set('my_key2', 200, scope='my_scope')

DFF.CACHE.mget([ 'my_key', 'my_key2' ], scope='my_scope')
# {'my_key': '100', 'my_key2': '200'}

DFF.CACHE.get_pattern(...)

Added in version 6.0.6

Get cache based on a key name matching pattern. Parameters are as follows:

Parameter	Type	Required / Default	Description
pattern	str	"*"	Key name matching pattern Supports * wildcard
scope	str	Current script name	Namespace

DFF.CACHE.set('my_key', 100, scope='my_scope')
DFF.CACHE.set('my_key2', 200, scope='my_scope')

DFF.CACHE.get_pattern('my_*', scope='my_scope')
# {'my_key2': '200', 'my_key': '100'}

DFF.CACHE.getset(...)

Get cache and simultaneously set a new cache value. Parameters are as follows:

Parameter	Type	Required / Default	Description
key	str	Required	Key name
value	str / int / float	Required	Data
scope	str	Current script name	Namespace

DFF.CACHE.set('my_key', 100, scope='my_scope')

DFF.CACHE.getset('my_key', 200, scope='my_scope')
# '100'

DFF.CACHE.incr(...)

Increment the cache value by a step. Parameters are as follows:

Parameter	Type	Required / Default	Description
key	str	Required	Key name
step	int	1	Step value
scope	str	Current script name	Namespace

DFF.CACHE.incr('my_key', scope='my_scope')

DFF.CACHE.incrby(...)

Increment the cache value by a specified step. Parameters are as follows:

Parameter	Type	Required / Default	Description
key	str	Required	Key name
step	int	Required	Step value
scope	str	Current script name	Namespace

DFF.CACHE.incrby('my_key', step=2, scope='my_scope')

Hash Methods

Using hash structures allows storing caches of the same type under the same Key, reducing the number of Keys in the main cache space.

DFF.CACHE.hkeys(...)

Get the list of fields in a hash structure. Parameters are as follows:

Parameter	Type	Required / Default	Description
key	str	Required	Key name
pattern	str	"*"	Field name matching pattern Supports * wildcard
scope	str	Current script name	Namespace

DFF.CACHE.hmset('user:001', { 'name': 'Tom', 'city': 'Beijing' }, scope='my_scope')

DFF.CACHE.hkeys('user:001', scope='userCache')
# ['name', 'city']

DFF.CACHE.hset(...)

Set the value of a specific field in a hash structure. Parameters are as follows:

Parameter	Type	Required / Default	Description
key	str	Required	Key name
field	str	Required	Field name
value	str / int / float	Required	Data
not_exists	bool	False	Write only if the field does not exist
scope	str	Current script name	Namespace

DFF.CACHE.hset('user:001', 'name', 'Tom', scope='my_scope')

DFF.CACHE.hmset(...)

Set multiple field values in a hash structure. Parameters are as follows:

Parameter	Type	Required / Default	Description
key	str	Required	Key name
obj	dict	Required	Data
scope	str	Current script name	Namespace

DFF.CACHE.hmset('user:001', { 'name': 'Tom', 'city': 'Beijing' }, scope='my_scope')

DFF.CACHE.hget(...)

Get the value of a field in a hash structure. Parameters are as follows:

Parameter	Type	Required / Default	Description
key	str	Required	Key name
field	str	Required	Field name
scope	str	Current script name	Namespace

DFF.CACHE.hmset('user:001', { 'name': 'Tom', 'city': 'Beijing', 'age': 20 }, scope='my_scope')

DFF.CACHE.hget('user:001', 'name', scope='my_scope')
# 'Tom'

DFF.CACHE.hmget(...)

Added in version 6.0.6

Get multiple field values in a hash structure. Parameters are as follows:

Parameter	Type	Required / Default	Description
key	str	Required	Key name
fields	list	Required	List of field names
scope	str	Current script name	Namespace

DFF.CACHE.hmset('user:001', { 'name': 'Tom', 'city': 'Beijing', 'age': 20 }, scope='my_scope')

DFF.CACHE.hmget('user:001', ['name', 'city'], scope='my_scope')
# {'name': 'Tom', 'city': 'Beijing'}

DFF.CACHE.hgetall(...)

Added in version 6.0.6

Get all field values in a hash structure. Parameters are as follows:

Parameter	Type	Required / Default	Description
key	str	Required	Key name
scope	str	Current script name	Namespace

DFF.CACHE.hmset('user:001', { 'name': 'Tom', 'city': 'Beijing', 'age': 20 }, scope='my_scope')

DFF.CACHE.hgetall('user:001', scope='my_scope')
# {'age': '20', 'city': 'Beijing', 'name': 'Tom'}

DFF.CACHE.hincr(...)

Added in version 6.0.6

Increment the value of a field in a hash structure by a step. Parameters are as follows:

Parameter	Type	Required / Default	Description
key	str	Required	Key name
field	str	Required	Field name
step	int	1	Step value
scope	str	Current script name	Namespace

DFF.CACHE.hincr('user:001', 'signCount', scope='my_scope')

DFF.CACHE.hincrby(...)

Added in version 6.0.6

Increment the value of a field in a hash structure by a specified step. Parameters are as follows:

Parameter	Type	Required / Default	Description
key	str	Required	Key name
field	str	Required	Field name
step	int	Required	Step value
scope	str	Current script name	Namespace

DFF.CACHE.hincrby('user:001', 'signCount', step=2, scope='my_scope')

DFF.CACHE.hdel(...)

Delete a field in a hash structure. Parameters are as follows:

Parameter	Type	Required / Default	Description
key	str	Required	Key name
field	str	Required	Field name
scope	str	Current script name	Namespace

DFF.CACHE.hmset('user:001', { 'name': 'Tom', 'city': 'Beijing' }, scope='my_scope')

DFF.CACHE.hdel('user:001', 'city', scope='my_scope')

List Methods

Using list structures allows storing multiple caches sequentially under the same Key, often used to implement queues, stacks, etc.

DFF.CACHE.lpush(...)

Add an element to the list structure from the left side. Parameters are as follows:

Parameter	Type	Required / Default	Description
key	str	Required	Key name
value	str / int / float	Required	Data
scope	str	Current script name	Namespace

DFF.CACHE.lpush('userQueue', '001', scope='queue')
DFF.CACHE.lpush('userQueue', '002', scope='queue')

DFF.CACHE.rpush(...)

Add an element to the list structure from the right side. Parameters are as follows:

Parameter	Type	Required / Default	Description
key	str	Required	Key name
value	str / int / float	Required	Data
scope	str	Current script name	Namespace

DFF.CACHE.rpush('userQueue', '001', scope='queue')
DFF.CACHE.rpush('userQueue', '002', scope='queue')

DFF.CACHE.lpop(...)

Pop an element from the list structure from the left side. Parameters are as follows:

Parameter	Type	Required / Default	Description
key	str	Required	Key name
scope	str	Current script name	Namespace

DFF.CACHE.lpush('userQueue', '001', scope='queue')
DFF.CACHE.lpush('userQueue', '002', scope='queue')

DFF.CACHE.lpop('userQueue', scope='queue')
# '002'

DFF.CACHE.rpop(...)

Pop an element from the list structure from the right side. Parameters are as follows:

Parameter	Type	Required / Default	Description
key	str	Required	Key name
scope	str	Current script name	Namespace

DFF.CACHE.lpush('userQueue', '001', scope='queue')
DFF.CACHE.lpush('userQueue', '002', scope='queue')

DFF.CACHE.rpop('userQueue', scope='queue')
# '001'

DFF.CACHE.blpop(...)

Added in version 6.0.6

Pop an element from the list structure from the left side in a blocking manner. Parameters are as follows:

Parameter	Type	Required / Default	Description
key	str / list	Required	Key name / List of key names
timeout	int	0	Blocking timeout duration (seconds)
scope	str	Current script name	Namespace

DFF.CACHE.lpush('userQueue', '001', scope='queue')
DFF.CACHE.lpush('userQueue', '002', scope='queue')

DFF.CACHE.blpop('userQueue', timeout=3, scope='queue')
# ['userQueue', '002']

DFF.CACHE.brpop(...)

Added in version 6.0.6

Pop an element from the list structure from the right side in a blocking manner. Parameters are as follows:

Parameter	Type	Required / Default	Description
key	str / list	Required	Key name / List of key names
timeout	int	0	Blocking timeout duration (seconds)
scope	str	Current script name	Namespace

DFF.CACHE.lpush('userQueue', '001', scope='queue')
DFF.CACHE.lpush('userQueue', '002', scope='queue')

DFF.CACHE.brpop('userQueue', timeout=3, scope='queue')
# ['userQueue', '001']

DFF.CACHE.rpoplpush(...)

Pop an element from the right side of one list structure, simultaneously push it to the left side of another list structure, and return this element. Parameters are as follows:

Parameter	Type	Required / Default	Description
key	str	Required	Key name (source)
dest_key	str	Same as key	Key name (destination)
scope	str	Current script name	Namespace (source)
dest_scope	str	Same as scope	Namespace (destination)

DFF.CACHE.lpush('userQueue', '001', scope='queue')
DFF.CACHE.lpush('userQueue', '002', scope='queue')
DFF.CACHE.lpush('userQueue', '003', scope='queue')

DFF.CACHE.rpoplpush('userQueue', 'userQueue2', scope='queue')
# '001'

DFF.CACHE.lpush('userQueue', '001', scope='queue')
DFF.CACHE.lpush('userQueue', '002', scope='queue')
DFF.CACHE.lpush('userQueue', '003', scope='queue')

DFF.CACHE.rpoplpush('userQueue', scope='queue')
# '001'

DFF.CACHE.rpoplpush('userQueue', scope='queue')
# '002'

DFF.CACHE.brpoplpush(...)

Added in version 6.0.6

Pop an element from the right side of one list structure, simultaneously push it to the left side of another list structure in a blocking manner, and return this element. Parameters are as follows:

Parameter	Type	Required / Default	Description
key	str	Required	Key name (source)
dest_key	str	Same as key	Key name (destination)
scope	str	Current script name	Namespace (source)
dest_scope	str	Same as scope	Namespace (destination)

DFF.CACHE.lpush('userQueue', '001', scope='queue')
DFF.CACHE.lpush('userQueue', '002', scope='queue')
DFF.CACHE.lpush('userQueue', '003', scope='queue')

DFF.CACHE.brpoplpush('userQueue', 'userQueue2', timeout=3, scope='queue')
# '001'

DFF.CACHE.llen(...)

Get the number of elements in a list structure. Parameters are as follows:

Parameter	Type	Required / Default	Description
key	str	Required	Key name
scope	str	Current script name	Namespace

DFF.CACHE.lpush('userQueue', '001', scope='queue')
DFF.CACHE.lpush('userQueue', '002', scope='queue')

DFF.CACHE.llen('userQueue', scope='queue')
# 2

DFF.CACHE.lrange(...)

Get a list of elements within a list structure (without popping). Parameters are as follows:

Parameter	Type	Required / Default	Description
key	str	Required	Key name
start	int	0	Start index (inclusive)
stop	int	-1	End index (inclusive, -1 means the last one)
scope	str	Current script name	Namespace

DFF.CACHE.rpush('userQueue', '001', scope='queue')
DFF.CACHE.rpush('userQueue', '002', scope='queue')
DFF.CACHE.rpush('userQueue', '003', scope='queue')
DFF.CACHE.rpush('userQueue', '004', scope='queue')

DFF.CACHE.lrange('userQueue', 0, 1, scope='queue')
# [ '001', '002' ]
DFF.CACHE.lrange('userQueue', 0, -1, scope='queue')
# [ '001', '002', '003', '004' ]

DFF.CACHE.ltrim(...)

Trim the list structure, keeping elements starting from the left side. Parameters are as follows:

Parameter	Type	Required / Default	Description
key	str	Required	Key name
start	int	Required	Start index (inclusive)
stop	int	Required	End index (inclusive, -1 means the last one)
scope	str	Current script name	Namespace

DFF.CACHE.rpush('userQueue', '001', scope='queue')
DFF.CACHE.rpush('userQueue', '002', scope='queue')
DFF.CACHE.rpush('userQueue', '003', scope='queue')
DFF.CACHE.rpush('userQueue', '004', scope='queue')

DFF.CACHE.ltrim('userQueue', 0, 1, scope='queue')

limit = 3
for i in range(100):
    DFF.CACHE.lpush('userQueue', i, scope='queue')
    DFF.CACHE.ltrim('userQueue', 0, limit, scope='queue')

Alias Methods

Added in version 6.0.6

Since PUSH/POP operations on list structures support both left-to-right and right-to-left directions.

To avoid confusion and ensure consistent operation direction, the following alias methods can be used.

Alias Method	Corresponding Actual Method
push	lpush
pop	rpop
bpop	brpop

Set Methods

Using set structures allows storing unique members.

DFF.CACHE.sadd(...)

Added in version 6.0.6

Add a member. Parameters are as follows:

Parameter	Type	Required / Default	Description
key	str	Required	Key name
member	str	Required	Member
scope	str	Current script name	Namespace

DFF.CACHE.sadd('staredUsers', 'user-001', scope='set')

DFF.CACHE.srem(...)

Added in version 6.0.6

Remove a member. Parameters are as follows:

Parameter	Type	Required / Default	Description
key	str	Required	Key name
member	str	Required	Member
scope	str	Current script name	Namespace

DFF.CACHE.srem('staredUsers', 'user-001', scope='set')

DFF.CACHE.scard(...)

Added in version 6.0.6

Get the number of members. Parameters are as follows:

Parameter	Type	Required / Default	Description
key	str	Required	Key name
scope	str	Current script name	Namespace

DFF.CACHE.scard('staredUsers', scope='set')
# 1

DFF.CACHE.smembers(...)

Added in version 6.0.6

Get the list of members. Parameters are as follows:

Parameter	Type	Required / Default	Description
key	str	Required	Key name
scope	str	Current script name	Namespace

DFF.CACHE.sadd('staredUsers', 'user-001', scope='set')
DFF.CACHE.sadd('staredUsers', 'user-002', scope='set')

DFF.CACHE.smembers('staredUsers', scope='set')
# ['user-002', 'user-001']

DFF.CACHE.sismember(...)

Added in version 6.0.6

Check if a member is in the set. Parameters are as follows:

Parameter	Type	Required / Default	Description
key	str	Required	Key name
member	str	Required	Member
scope	str	Current script name	Namespace

DFF.CACHE.sadd('staredUsers', 'user-001', scope='set')
DFF.CACHE.sadd('staredUsers', 'user-002', scope='set')

DFF.CACHE.sismember('staredUsers', 'user-002', scope='set')
# True

Sorted Set Methods

Using sorted set structures allows storing unique members and maintaining order based on a specified score (score, int / float type).

DFF.CACHE.zadd(...)

Added in version 6.0.6

Add a member. Parameters are as follows:

Parameter	Type	Required / Default	Description
key	str	Required	Key name
member_scores	dict	Required	Member-score dictionary
scope	str	Current script name	Namespace

data = {
  'user-001': 100,
  'user-002': 200,
}
DFF.CACHE.zadd('staredUsers', data, scope='zset')

DFF.CACHE.zrem(...)

Added in version 6.0.6

Remove a member. Parameters are as follows:

Parameter	Type	Required / Default	Description
key	str	Required	Key name
member	str	Required	Member
scope	str	Current script name	Namespace

DFF.CACHE.zrem('staredUsers', 'user-001', scope='zset')

DFF.CACHE.zcard(...)

Added in version 6.0.6

Get the number of members. Parameters are as follows:

Parameter	Type	Required / Default	Description
key	str	Required	Key name
scope	str	Current script name	Namespace

DFF.CACHE.zcard('staredUsers', scope='zset')
# 1

DFF.CACHE.zrange(...)

Added in version 6.0.6

Get members based on Score order index. Parameters are as follows:

Parameter	Type	Required / Default	Description
key	str	Required	Key name
start	int	0	Start index (inclusive)
stop	int	-1	End index (inclusive, -1 means the last one)
reverse	boolean	False	Whether to output in reverse order
with_scores	boolean	False	Whether to return scores simultaneously
scope	str	Current script name	Namespace

data = {
  'user-001': 100,
  'user-002': 200,
  'user-003': 300,
}
DFF.CACHE.zadd('staredUsers', data, scope='zset')

DFF.CACHE.zrange('staredUsers', scope='zset')
# ['user-001', 'user-002', 'user-003']
DFF.CACHE.zrange('staredUsers', start=1, stop=-1, scope='zset')
# ['user-002', 'user-003']
DFF.CACHE.zrange('staredUsers', with_scores=True, scope='zset')
# [['user-001', 100.0], ['user-002', 200.0], ['user-003', 300.0]]

DFF.CACHE.zrangebyscore(...)

Added in version 6.0.6

Get members based on Score. Parameters are as follows:

Parameter	Type	Required / Default	Description
key	str	Required	Key name
min_score	int	"-inf"	Start score (inclusive, "-inf" means minimum value)
max_score	int	"+inf"	End score (inclusive, "+inf" means maximum value)
with_scores	boolean	False	Whether to return scores simultaneously
scope	str	Current script name	Namespace

data = {
  'user-001': 100,
  'user-002': 200,
  'user-003': 300,
}
DFF.CACHE.zadd('staredUsers', data, scope='zset')

DFF.CACHE.zrangebyscore('staredUsers', scope='zset')
# ['user-001', 'user-002', 'user-003']
DFF.CACHE.zrangebyscore('staredUsers', min_score=200, max_score=200, scope='zset')
# ['user-002']
DFF.CACHE.zrangebyscore('staredUsers', with_scores=True, scope='zset')
# [['user-001', 100.0], ['user-002', 200.0], ['user-003', 300.0]]

Pub/Sub Methods

Using Pub/Sub methods allows sending messages to clients subscribed to specific topics.

DFF.CACHE.publish(...)

Publish a message to a topic. Parameters are as follows:

Parameter	Type	Required / Default	Description
topic	str	Required	Topic
message	str	Required	Message content
scope	str	Current script name	Namespace

DFF.CACHE.publish('some_topic', 'hello', scope='app')