## 協程Coroutine
```
go(function () {
$redis = new Swoole\Coroutine\Redis();
$redis->connect('127.0.0.1', 6379);
$val = $redis->get('key');
});
```
<br>
協程可以理解為純用戶態的線程,其通過**協作**而不是搶占來進行切換。相對于進程或者線程,協程所有的操作都可以在用戶態完成,創建和切換的消耗更低。`Swoole`可以為每一個請求創建對應的協程,根據`IO`的狀態來合理的調度協程,這會帶來了以下優勢:
1. 開發者可以無感知的用同步的代碼編寫方式達到異步IO的效果和性能,避免了傳統異步回調所帶來的離散的代碼邏輯和陷入多層回調中導致代碼無法維護
2. 同時由于底層封裝了協程,所以對比傳統的`PHP`層協程框架,開發者不需要使用`yield`關鍵詞來標識一個協程`IO`操作,所以不再需要對`yield`的語義進行深入理解以及對每一級的調用都修改為`yield`,這極大的提高了開發效率
<br>
## 協程應用場景:
類型ajax的異步操作。大數據處理,直接返回結果,耗時操作放協程里執行完成再返回結果。同步的編程邏輯實現異步的效果。
```
go(function () {
co::sleep(2);
echo "hello".PHP_EOL;
});
echo 'ok';
```
輸出:
```
ok
hello
```
- 序章
- 1.環境搭建
- PHP7源碼編譯安裝
- Swoole源碼編譯安裝
- Mysql5.7源碼安裝
- Redis安裝
- 2.搭建Echo服務器
- 3.Server服務器
- 函數列表
- Server::__construct
- Server->set
- Server->on
- Server->start
- Server->send
- WebSocket
- Server->push
- Server->exist
- Server::pack
- Server::unpack
- Server->disconnect
- Server->isEstablished
- 配置選項
- reactor_num
- worker_num
- max_request
- max_conn
- daemonize
- backlog
- log_file
- log_level
- upload_tmp_dir
- http_parse_post
- document_root
- http_compression
- 事件回調函數
- onStart
- onWorkerStart
- onConnect
- onReceive
- onPacket
- onRequest
- 請求Request
- Http\Request->$header
- Http\Request->$server
- Http\Request->$get
- Http\Request->$post
- Http\Request->$cookie
- Http\Request->$files
- Http\Request->rawContent
- Http\Request->getData
- 響應Response
- Http\Response->header
- Http\Response->cookie
- Http\Response->status
- Http\Response->redirect
- Http\Response->write
- Http\Response->sendfile
- Http\Response->end
- Http\Response->detach
- Http\Response::create
- onClose
- onOpen
- onMessage
- 創建服務器
- TCP服務器
- UDP服務器
- HTTP服務器
- WebSocket服務器
- 4.定時器Timer
- 5.進程Process
- Process::__construct
- Process->start
- Process->name
- Process->exec
- Process->write
- Process->read
- Process->setTimeout
- Process->setBlocking
- Process->useQueue
- Process->statQueue
- Process->freeQueue
- Process->push
- Process->pop
- Process->close
- Process->exit
- Process::kill
- Process::wait
- Process::daemon
- Process::signal
- 6.內存Memory
- Table
- Table->__construct
- Table->column
- Table->create
- Table->set
- Table->incr
- Table->decr
- Table->get
- Table->exist
- Table->count
- Table->del
- Channel
- Channel->__construct
- Channel->push
- Channel->pop
- Channel->stats
- 7.協程Coroutine
- Coroutine
- Coroutine::list
- Coroutine::set
- Coroutine::stats
- Coroutine::create
- Coroutine::exist
- Coroutine::getCid
- Coroutine::getContext
- Coroutine::defer
- Coroutine::getBackTrace
- Coroutine::yield
- Coroutine::resume
- Coroutine::fread
- Coroutine::fgets
- Coroutine::fwrite
- Coroutine::sleep
- Coroutine::gethostbyname
- Coroutine::getaddrinfo
- Coroutine::exec
- Coroutine::readFile
- Coroutine::writeFile
- Coroutine::statvfs
- Coroutine::getPcid
- Coroutine\Channel
- Coroutine\Channel->__construct
- Coroutine\Channel->push
- Coroutine\Channel->pop
- Coroutine\Channel->stats
- Coroutine\Channel->close
- Coroutine\Channel->length
- Coroutine\Channel->isEmpty
- Coroutine\Channel->isFull
- Coroutine\Channel->$capacity
- Coroutine\Channel->$errCode
- Coroutine\Client
- Coroutine\Client->connect
- Coroutine\Client->send
- Coroutine\Client->recv
- Coroutine\Client->close
- Coroutine\Client->peek
- Coroutine\Client->set
- Coroutine\Http\Client
- Coroutine\Http\Client->get
- Coroutine\Http\Client->post
- 其他
- 并行和并發的區別
- 堆、棧、隊列