Application scenarios of channel of go question bank · 11

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「 title 」GOLANG ROADMAP Community

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「 answer 」（engine）

channel It is applicable to scenarios where data flows in multiple processes , There are many practical applications ：

① Task timing

For example, timeout processing ：

select {
    case <-time.After(time.Second):

Timing task

select {
    case <- time.Tick(time.Second)

② Decoupling producers and consumers

Producers and consumers can be decoupled , Producers only need to go to channel send data , And consumers just go from channel Get data in .

③ Control concurrency

Take reptiles for example , Such as crawling 1w Data , Concurrent crawling is required to improve efficiency , But the concurrency should not be too large , Can pass channel To control the concurrency scale , For example, support at the same time 5 Concurrent tasks ：

ch := make(chan int, 5)
for _, url := range urls {
  go func() {
    ch <- 1
    worker(url)
    <- ch
  }
}