Script Development / Simple Cache DFF.CACHE

DataFlux Func has a built-in simple cache feature DFF.CACHE based on Redis. For scenarios that require data caching but are not complex, this built-in cache feature can be used directly.

The storage structure is Scope-Key-Value, allowing the same Key to exist under different namespaces.

Simple Cache does not preserve original data types

When operating the simple cache, whether you write a string or a number in the code, it will be read back as a string.

Users need to handle the read content themselves and perform appropriate type conversion or deserialization.

General Methods

Some methods related to the cache database itself and unrelated to 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 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 the cache, parameters are as follows:

Parameter	Type	Required / Default	Description
key	str	Required	Key name
expire	int	None	Expiration time. Unit: seconds None means no expiration
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 the 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 (in 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 pattern, parameters are as follows:

Parameter	Type	Required / Default	Description
pattern	str	"*"	Key name 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 related to values written via DFF.CACHE.set(...).

DFF.CACHE.set(...)

Create a 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 no expiration
not_exists	bool	False	Write only if the Key does not exist
exists	bool	False	Write only if the Key exists
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 create 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	str	Required	Key name list
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 pattern, parameters are as follows:

Parameter	Type	Required / Default	Description
pattern	str	"*"	Key name 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 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 the hash structure, you can store caches of the same type under the same Key, reducing the number of Keys in the main cache space.

DFF.CACHE.hkeys(...)

Get a 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 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 a field value 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 a field value from 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 from a hash structure, parameters are as follows:

Parameter	Type	Required / Default	Description
key	str	Required	Key name
fields	list	Required	Field name list
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 from 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 a field value 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 a field value 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 from 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 the list structure, you can store multiple caches in order under the same Key, often used to implement queues, stacks, etc.

DFF.CACHE.lpush(...)

Add an element to the left side of a list structure, 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 right side of a list structure, 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 left side of 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.lpop('userQueue', scope='queue')
# '002'

DFF.CACHE.rpop(...)

Pop an element from the right side of 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.rpop('userQueue', scope='queue')
# '001'

DFF.CACHE.blpop(...)

Added in version 6.0.6

Pop an element from the left side of a list structure in a blocking manner, parameters are as follows:

Parameter	Type	Required / Default	Description
key	str / list	Required	Key name / Key name list
timeout	int	0	Blocking timeout (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 right side of a list structure in a blocking manner, parameters are as follows:

Parameter	Type	Required / Default	Description
key	str / list	Required	Key name / Key name list
timeout	int	0	Blocking timeout (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 a list structure and push it to the left side of another list structure, and return the 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 a list structure in a blocking manner and push it to the left side of another list structure, and return the 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 in 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(...)

Keep elements in a list structure 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.

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 the set structure, you can save non-repeating 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

Delete 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 a 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
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 the sorted set structure, you can save non-repeating members and keep them ordered by 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

Delete 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 by 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 reverse output
with_scores	boolean	False	Whether to return scores
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 by 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
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.zrangebysscore('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]]

Message Methods

Using message methods, you can send 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')