Event

Event (libevent 기반 이벤트 확장)

I/O, 시간, 시그널 기반 이벤트를 효율적으로 스케줄링하고 싶을 때 쓰는 확장이에요. 사용 가능한 최선의 I/O 알림 메커니즘을 활용해 이벤트를 처리하며, libevent를 PHP 인프라로 포팅한 거예요. 비동기·이벤트 기반 프로그래밍이 필요할 때 씁니다.

출처: Event

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소개

이 확장은 특정 플랫폼에서 사용 가능한 최선의 I/O 알림 메커니즘을 이용해 I/O, 시간, 시그널 기반 이벤트를 효율적으로 스케줄링하는 확장이에요. libevent를 PHP 인프라에 포팅한 거죠.

기억해 둘 버전 관련 내용이 몇 가지 있어요.

• Windows 지원은 event-1.9.0부터 도입됐어요.
• 버전 1.0.0은 새로운 객체 지향 API(하위 호환을 깨는 변경)를 도입하고, HTTP, DNS, OpenSSL, 이벤트 리스너를 포함한 libevent 2+를 지원해요.
• event-1.0.0 이상은 이전 버전과 호환되지 않아요.

주요 클래스 흐름은 EventBase(이벤트 루프/베이스), Event(개별 이벤트), EventBuffer(버퍼), EventBufferEvent(버퍼 이벤트) 등으로 구성돼요. 네트워크 프로그래밍에서 비동기 I/O를 처리할 때 특히 유용해요.

클래스 참조

Event — The Event class

• Event::add — Makes event pending
• Event::addSignal — Alias of Event::add
• Event::addTimer — Alias of Event::add
• Event::__construct — Constructs Event object
• Event::del — Makes event non-pending
• Event::delSignal — Alias of Event::del
• Event::delTimer — Alias of Event::del
• Event::free — Make event non-pending and free resources allocated for this event
• Event::getSupportedMethods — Returns array of the names of the methods supported in this version of Libevent
• Event::pending — Detects whether event is pending or scheduled
• Event::set — Re-configures event
• Event::setPriority — Set event priority
• Event::setTimer — Re-configures timer event
• Event::signal — Constructs signal event object
• Event::timer — Constructs timer event object

EventBase — The EventBase class

• EventBase::__construct — Constructs EventBase object
• EventBase::dispatch — Dispatch pending events
• EventBase::exit — Stop dispatching events
• EventBase::free — Free resources allocated for this event base
• EventBase::getFeatures — Returns bitmask of features supported
• EventBase::getMethod — Returns event method in use
• EventBase::getTimeOfDayCached — Returns the current event base time
• EventBase::gotExit — Checks if the event loop was told to exit
• EventBase::gotStop — Checks if the event loop was told to exit
• EventBase::loop — Dispatch pending events
• EventBase::priorityInit — Sets number of priorities per event base
• EventBase::reInit — Re-initialize event base (after a fork)
• EventBase::stop — Tells event_base to stop dispatching events

EventBuffer — The EventBuffer class

• EventBuffer::add — Append data to the end of an event buffer
• EventBuffer::addBuffer — Move all data from a buffer provided to the current instance of EventBuffer
• EventBuffer::appendFrom — Moves the specified number of bytes from a source buffer to the end of the current buffer
• EventBuffer::__construct — Constructs EventBuffer object
• EventBuffer::copyout — Copies out specified number of bytes from the front of the buffer
• EventBuffer::drain — Removes specified number of bytes from the front of the buffer without copying it anywhere
• EventBuffer::enableLocking — Description
• EventBuffer::expand — Reserves space in buffer
• EventBuffer::freeze — Prevent calls that modify an event buffer from succeeding
• EventBuffer::lock — Acquires a lock on buffer
• EventBuffer::prepend — Prepend data to the front of the buffer
• EventBuffer::prependBuffer — Moves all data from source buffer to the front of current buffer
• EventBuffer::pullup — Linearizes data within buffer and returns its contents as a string
• EventBuffer::read — Read data from an evbuffer and drain the bytes read
• EventBuffer::readFrom — Read data from a file onto the end of the buffer
• EventBuffer::readLine — Extracts a line from the front of the buffer
• EventBuffer::search — Scans the buffer for an occurrence of a string
• EventBuffer::searchEol — Scans the buffer for an occurrence of an end of line
• EventBuffer::substr — Subtracts a portion of the buffer data
• EventBuffer::unfreeze — Re-enable calls that modify an event buffer
• EventBuffer::unlock — Releases lock acquired by EventBuffer::lock
• EventBuffer::write — Write contents of the buffer to a file or socket

EventBufferEvent — The EventBufferEvent class

• EventBufferEvent::close — Closes file descriptor associated with the current buffer event
• EventBufferEvent::connect — Connect buffer event's file descriptor to given address or UNIX socket
• EventBufferEvent::connectHost — Connects to a hostname with optionally asynchronous DNS resolving
• EventBufferEvent::__construct — Constructs EventBufferEvent object
• EventBufferEvent::createPair — Creates two buffer events connected to each other
• EventBufferEvent::disable — Disable events read, write, or both on a buffer event
• EventBufferEvent::enable — Enable events read, write, or both on a buffer event
• EventBufferEvent::free — Free a buffer event
• EventBufferEvent::getDnsErrorString — Returns string describing the last failed DNS lookup attempt
• EventBufferEvent::getEnabled — Returns bitmask of events currently enabled on the buffer event
• EventBufferEvent::getInput — Returns underlying input buffer associated with current buffer event
• EventBufferEvent::getOutput — Returns underlying output buffer associated with current buffer event
• EventBufferEvent::read — Read buffer's data
• EventBufferEvent::readBuffer — Drains the entire contents of the input buffer and places them into buf
• EventBufferEvent::setCallbacks — Assigns read, write and event(status) callbacks
• EventBufferEvent::setPriority — Assign a priority to a bufferevent
• EventBufferEvent::setTimeouts — Set the read and write timeout for a buffer event
• EventBufferEvent::setWatermark — Adjusts read and/or write watermarks
• EventBufferEvent::sslError — Returns most recent OpenSSL error reported on the buffer event
• EventBufferEvent::sslFilter — Create a new SSL buffer event to send its data over another buffer event
• EventBufferEvent::sslGetCipherInfo — Returns a textual description of the cipher
• EventBufferEvent::sslGetCipherName — Returns the current cipher name of the SSL connection
• EventBufferEvent::sslGetCipherVersion — Returns version of cipher used by current SSL connection
• EventBufferEvent::sslGetProtocol — Returns the name of the protocol used for current SSL connection
• EventBufferEvent::sslRenegotiate — Tells a bufferevent to begin SSL renegotiation
• EventBufferEvent::sslSocket — Creates a new SSL buffer event to send its data over an SSL on a socket
• EventBufferEvent::write — Adds data to a buffer event's output buffer
• EventBufferEvent::writeBuffer — Adds contents of the entire buffer to a buffer event's output buffer

EventConfig — The EventConfig class

• EventConfig::avoidMethod — Tells libevent to avoid specific event method
• EventConfig::__construct — Constructs EventConfig object
• EventConfig::requireFeatures — Enters a required event method feature that the application demands
• EventConfig::setFlags — Sets one or more flags that configure how the eventual EventBase will be initialized
• EventConfig::setMaxDispatchInterval — Prevents priority inversion

EventDnsBase — The EventDnsBase class

• EventDnsBase::addNameserverIp — Adds a nameserver to the DNS base
• EventDnsBase::addSearch — Adds a domain to the list of search domains
• EventDnsBase::clearSearch — Removes all current search suffixes
• EventDnsBase::__construct — Constructs EventDnsBase object
• EventDnsBase::countNameservers — Gets the number of configured nameservers
• EventDnsBase::loadHosts — Loads a hosts file (in the same format as /etc/hosts) from hosts file
• EventDnsBase::parseResolvConf — Scans the resolv.conf-formatted file
• EventDnsBase::setOption — Set the value of a configuration option
• EventDnsBase::setSearchNdots — Set the 'ndots' parameter for searches

EventHttp — The EventHttp class

• EventHttp::accept — Makes an HTTP server accept connections on the specified socket stream or resource
• EventHttp::addServerAlias — Adds a server alias to the HTTP server object
• EventHttp::bind — Binds an HTTP server on the specified address and port
• EventHttp::__construct — Constructs EventHttp object (the HTTP server)
• EventHttp::removeServerAlias — Removes server alias
• EventHttp::setAllowedMethods — Sets which HTTP methods are supported in requests accepted by this server, and passed to user callbacks
• EventHttp::setCallback — Sets a callback for specified URI
• EventHttp::setDefaultCallback — Sets default callback to handle requests that are not caught by specific callbacks
• EventHttp::setMaxBodySize — Sets maximum request body size
• EventHttp::setMaxHeadersSize — Sets maximum HTTP header size
• EventHttp::setTimeout — Sets the timeout for an HTTP request

EventHttpConnection — The EventHttpConnection class

• EventHttpConnection::__construct — Constructs EventHttpConnection object
• EventHttpConnection::getBase — Returns event base associated with the connection
• EventHttpConnection::getPeer — Gets the remote address and port associated with the connection
• EventHttpConnection::makeRequest — Makes an HTTP request over the specified connection
• EventHttpConnection::setCloseCallback — Set callback for connection close
• EventHttpConnection::setLocalAddress — Sets the IP address from which HTTP connections are made
• EventHttpConnection::setLocalPort — Sets the local port from which connections are made
• EventHttpConnection::setMaxBodySize — Sets maximum body size for the connection
• EventHttpConnection::setMaxHeadersSize — Sets maximum header size
• EventHttpConnection::setRetries — Sets the retry limit for the connection
• EventHttpConnection::setTimeout — Sets the timeout for the connection

EventHttpRequest — The EventHttpRequest class

• EventHttpRequest::addHeader — Adds an HTTP header to the headers of the request
• EventHttpRequest::cancel — Cancels a pending HTTP request
• EventHttpRequest::clearHeaders — Removes all output headers from the header list of the request
• EventHttpRequest::closeConnection — Closes associated HTTP connection
• EventHttpRequest::__construct — Constructs EventHttpRequest object
• EventHttpRequest::findHeader — Finds the value belonging to a header
• EventHttpRequest::free — Frees the object and removes associated events
• EventHttpRequest::getBufferEvent — Returns EventBufferEvent object
• EventHttpRequest::getCommand — Returns the request command(method)
• EventHttpRequest::getConnection — Returns EventHttpConnection object
• EventHttpRequest::getHost — Returns the request host
• EventHttpRequest::getInputBuffer — Returns the input buffer
• EventHttpRequest::getInputHeaders — Returns associative array of the input headers
• EventHttpRequest::getOutputBuffer — Returns the output buffer of the request
• EventHttpRequest::getOutputHeaders — Returns associative array of the output headers
• EventHttpRequest::getResponseCode — Returns the response code
• EventHttpRequest::getUri — Returns the request URI
• EventHttpRequest::removeHeader — Removes an HTTP header from the headers of the request
• EventHttpRequest::sendError — Send an HTML error message to the client
• EventHttpRequest::sendReply — Send an HTML reply to the client
• EventHttpRequest::sendReplyChunk — Send another data chunk as part of an ongoing chunked reply
• EventHttpRequest::sendReplyEnd — Complete a chunked reply, freeing the request as appropriate
• EventHttpRequest::sendReplyStart — Initiate a chunked reply

EventListener — The EventListener class

• EventListener::__construct — Creates new connection listener associated with an event base
• EventListener::disable — Disables an event connect listener object
• EventListener::enable — Enables an event connect listener object
• EventListener::getBase — Returns event base associated with the event listener
• EventListener::getSocketName — Retrieves the current address to which the listener's socket is bound
• EventListener::setCallback — The setCallback purpose
• EventListener::setErrorCallback — Set event listener's error callback

EventSslContext — The EventSslContext class

• EventSslContext::__construct — Constructs an OpenSSL context for use with Event classes

EventUtil — The EventUtil class

• EventUtil::__construct — The abstract constructor
• EventUtil::getLastSocketErrno — Returns the most recent socket error number
• EventUtil::getLastSocketError — Returns the most recent socket error
• EventUtil::getSocketFd — Returns numeric file descriptor of a socket, or stream
• EventUtil::getSocketName — Retrieves the current address to which the socket is bound
• EventUtil::setSocketOption — Sets socket options
• EventUtil::sslRandPoll — Generates entropy by means of OpenSSL's RAND_poll()

예외 클래스

• EventException — The EventException class

더 알아보기

• 이벤트 루프의 중심이 되는 EventBase를 만들고, 그 위에 Event나 EventBufferEvent를 얹어 비동기 I/O를 처리하는 구조예요. 처음엔 '이벤트 언제든 pending/비pending 상태가 바뀐다'는 흐름을 이해하는 게 중요해요.
• 버전 주의사항을 꼭 확인하세요. 1.0.0 이후는 이전 버전과 호환되지 않고, Windows 지원은 1.9.0부터예요.