redis PUBSUB command

pub

UK[pʌb] 美[pʌb]

n.Pub, hotel; inn

plural: pubs

sub

英[sʌb] 美[sʌb]

n. Submarine; substitute, substitute, substitute; subway; reviewer Member

vi.Be a stand-in, be a substitute player; be a stand-in, proofread (manuscript)

Third person singular: subs Plural: subs Present participle: subbing Past tense: subbed Past participle: subbed

redis PUBSUB commandsyntax

Function:PUBSUB is an introspection command for viewing the status of subscription and publishing systems. It consists of several subcommands in different formats.

Syntax: PUBSUB <subcommand> [argument [argument ...]]

Available versions: >= 2.8.0

Time complexity: O(N), N is the number of active channels (for shorter channels and patterns, the complexity of pattern matching is treated as a constant).

Returns: A list of active channels.

redis PUBSUB commandexample

# client-1 订阅 news.it 和 news.sport 两个频道
client-1> SUBSCRIBE news.it news.sport
Reading messages... (press Ctrl-C to quit)
1) "subscribe"
2) "news.it"
3) (integer) 1
1) "subscribe"
2) "news.sport"
3) (integer) 2
# client-2 订阅 news.it 和 news.internet 两个频道
client-2> SUBSCRIBE news.it news.internet
Reading messages... (press Ctrl-C to quit)
1) "subscribe"
2) "news.it"
3) (integer) 1
1) "subscribe"
2) "news.internet"
3) (integer) 2
# 首先， client-3 打印所有活跃频道
# 注意，即使一个频道有多个订阅者，它也只输出一次，比如 news.it
client-3> PUBSUB CHANNELS
1) "news.sport"
2) "news.internet"
3) "news.it"
# 接下来， client-3 打印那些与模式 news.i* 相匹配的活跃频道
# 因为 news.sport 不匹配 news.i* ，所以它没有被打印
redis> PUBSUB CHANNELS news.i*
1) "news.internet"
2) "news.it"