HTTP
目录
- Class: http.Agent
- Class: http.ClientRequest
- Event: 'abort'
- Event: 'close'
- Event: 'connect'
- Event: 'continue'
- Event: 'finish'
- Event: 'information'
- Event: 'response'
- Event: 'socket'
- Event: 'timeout'
- Event: 'upgrade'
- request.abort()
- request.aborted
- request.connection
- request.cork()
- request.end([data[, encoding]][, callback])
- request.destroy([error])
- request.finished
- request.flushHeaders()
- request.getHeader(name)
- request.getHeaderNames()
- request.getHeaders()
- request.getRawHeaderNames()
- request.hasHeader(name)
- request.maxHeadersCount
- request.path
- request.method
- request.host
- request.protocol
- request.removeHeader(name)
- request.reusedSocket
- request.setHeader(name, value)
- request.setNoDelay([noDelay])
- request.setSocketKeepAlive([enable][, initialDelay])
- request.setTimeout(timeout[, callback])
- request.socket
- request.uncork()
- request.writableEnded
- request.writableFinished
- request.write(chunk[, encoding][, callback])
- Class: http.Server
- Event: 'checkContinue'
- Event: 'checkExpectation'
- Event: 'clientError'
- Event: 'close'
- Event: 'connect'
- Event: 'connection'
- Event: 'dropRequest'
- Event: 'request'
- Event: 'upgrade'
- server.close([callback])
- server.closeAllConnections()
- server.closeIdleConnections()
- server.headersTimeout
- server.listen()
- server.listening
- server.maxHeadersCount
- server.requestTimeout
- server.setTimeout([msecs][, callback])
- server.maxRequestsPerSocket
- server.timeout
- server.keepAliveTimeout
- Class: http.ServerResponse
- Event: 'close'
- Event: 'finish'
- response.addTrailers(headers)
- response.connection
- response.cork()
- response.end([data[, encoding]][, callback])
- response.finished
- response.flushHeaders()
- response.getHeader(name)
- response.getHeaderNames()
- response.getHeaders()
- response.hasHeader(name)
- response.headersSent
- response.removeHeader(name)
- response.req
- response.sendDate
- response.setHeader(name, value)
- response.setTimeout(msecs[, callback])
- response.socket
- response.statusCode
- response.statusMessage
- response.uncork()
- response.writableEnded
- response.writableFinished
- response.write(chunk[, encoding][, callback])
- response.writeContinue()
- response.writeEarlyHints(hints[, callback])
- response.writeHead(statusCode[, statusMessage][, headers])
- response.writeProcessing()
- Class: http.IncomingMessage
- Event: 'aborted'
- Event: 'close'
- message.aborted
- message.complete
- message.connection
- message.destroy([error])
- message.headers
- message.headersDistinct
- message.httpVersion
- message.method
- message.rawHeaders
- message.rawTrailers
- message.setTimeout(msecs[, callback])
- message.socket
- message.statusCode
- message.statusMessage
- message.trailers
- message.trailersDistinct
- message.url
- Class: http.OutgoingMessage
- Event: 'drain'
- Event: 'finish'
- Event: 'prefinish'
- outgoingMessage.addTrailers(headers)
- outgoingMessage.appendHeader(name, value)
- outgoingMessage.connection
- outgoingMessage.cork()
- outgoingMessage.destroy([error])
- outgoingMessage.end(chunk[, encoding][, callback])
- outgoingMessage.flushHeaders()
- outgoingMessage.getHeader(name)
- outgoingMessage.getHeaderNames()
- outgoingMessage.getHeaders()
- outgoingMessage.hasHeader(name)
- outgoingMessage.headersSent
- outgoingMessage.pipe()
- outgoingMessage.removeHeader(name)
- outgoingMessage.setHeader(name, value)
- outgoingMessage.setTimeout(msesc[, callback])
- outgoingMessage.socket
- outgoingMessage.uncork()
- outgoingMessage.writableCorked
- outgoingMessage.writableEnded
- outgoingMessage.writableFinished
- outgoingMessage.writableHighWaterMark
- outgoingMessage.writableLength
- outgoingMessage.writableObjectMode
- outgoingMessage.write(chunk[, encoding][, callback])
- http.METHODS
- http.STATUS_CODES
- http.createServer([options][, requestListener])
- http.get(options[, callback])
- http.get(url[, options][, callback])
- http.globalAgent
- http.maxHeaderSize
- http.request(options[, callback])
- http.request(url[, options][, callback])
- http.validateHeaderName(name)
- http.validateHeaderValue(name, value)
- http.setMaxIdleHTTPParsers
自 v0.10.0 版本开始新增
源代码: lib/http.js
To use the HTTP server and client one must require('node:http')
.
The HTTP interfaces in Node.js are designed to support many features of the protocol which have been traditionally difficult to use. In particular, large, possibly chunk-encoded, messages. The interface is careful to never buffer entire requests or responses, so the user is able to stream data.
HTTP message headers are represented by an object like this:
JS
Keys are lowercased. Values are not modified.
In order to support the full spectrum of possible HTTP applications, the Node.js HTTP API is very low-level. It deals with stream handling and message parsing only. It parses a message into headers and body but it does not parse the actual headers or the body.
See message.headers
for details on how duplicate headers are handled.
The raw headers as they were received are retained in the rawHeaders
property, which is an array of [key, value, key2, value2, ...]
. For
example, the previous message header object might have a rawHeaders
list like the following:
JS
C http.Agent
自 v0.3.4 版本开始新增
An Agent
is responsible for managing connection persistence
and reuse for HTTP clients. It maintains a queue of pending requests
for a given host and port, reusing a single socket connection for each
until the queue is empty, at which time the socket is either destroyed
or put into a pool where it is kept to be used again for requests to the
same host and port. Whether it is destroyed or pooled depends on the
keepAlive
option.
Pooled connections have TCP Keep-Alive enabled for them, but servers may
still close idle connections, in which case they will be removed from the
pool and a new connection will be made when a new HTTP request is made for
that host and port. Servers may also refuse to allow multiple requests
over the same connection, in which case the connection will have to be
remade for every request and cannot be pooled. The Agent
will still make
the requests to that server, but each one will occur over a new connection.
When a connection is closed by the client or the server, it is removed
from the pool. Any unused sockets in the pool will be unrefed so as not
to keep the Node.js process running when there are no outstanding requests.
(see socket.unref()
).
It is good practice, to destroy()
an Agent
instance when it is no
longer in use, because unused sockets consume OS resources.
Sockets are removed from an agent when the socket emits either
a 'close'
event or an 'agentRemove'
event. When intending to keep one
HTTP request open for a long time without keeping it in the agent, something
like the following may be done:
JS
An agent may also be used for an individual request. By providing
{agent: false}
as an option to the http.get()
or http.request()
functions, a one-time use Agent
with default options will be used
for the client connection.
agent:false
:
JS
M new Agent([options])
历史
版本 | 历史变更 |
---|---|
v15.6.0, v14.17.0 | Change the default scheduling from 'fifo' to 'lifo'. |
v14.5.0, v12.19.0 | Add `maxTotalSockets` option to agent constructor. |
v14.5.0, v12.20.0 | Add `scheduling` option to specify the free socket scheduling strategy. |
v0.3.4 | 自 v0.3.4 版本开始新增 |
options
Object
Set of configurable options to set on the agent. Can have the following fields:keepAlive
boolean
Keep sockets around even when there are no outstanding requests, so they can be used for future requests without having to reestablish a TCP connection. Not to be confused with thekeep-alive
value of theConnection
header. TheConnection: keep-alive
header is always sent when using an agent except when theConnection
header is explicitly specified or when thekeepAlive
andmaxSockets
options are respectively set tofalse
andInfinity
, in which caseConnection: close
will be used. Default:false
.keepAliveMsecs
number
When using thekeepAlive
option, specifies the initial delay for TCP Keep-Alive packets. Ignored when thekeepAlive
option isfalse
orundefined
. Default:1000
.maxSockets
number
Maximum number of sockets to allow per host. If the same host opens multiple concurrent connections, each request will use new socket until themaxSockets
value is reached. If the host attempts to open more connections thanmaxSockets
, the additional requests will enter into a pending request queue, and will enter active connection state when an existing connection terminates. This makes sure there are at mostmaxSockets
active connections at any point in time, from a given host. Default:Infinity
.maxTotalSockets
number
Maximum number of sockets allowed for all hosts in total. Each request will use a new socket until the maximum is reached. Default:Infinity
.maxFreeSockets
number
Maximum number of sockets per host to leave open in a free state. Only relevant ifkeepAlive
is set totrue
. Default:256
.scheduling
string
Scheduling strategy to apply when picking the next free socket to use. It can be'fifo'
or'lifo'
. The main difference between the two scheduling strategies is that'lifo'
selects the most recently used socket, while'fifo'
selects the least recently used socket. In case of a low rate of request per second, the'lifo'
scheduling will lower the risk of picking a socket that might have been closed by the server due to inactivity. In case of a high rate of request per second, the'fifo'
scheduling will maximize the number of open sockets, while the'lifo'
scheduling will keep it as low as possible. Default:'lifo'
.timeout
number
Socket timeout in milliseconds. This will set the timeout when the socket is created.
options
in socket.connect()
are also supported.
The default http.globalAgent
that is used by http.request()
has all
of these values set to their respective defaults.
To configure any of them, a custom http.Agent
instance must be created.
JS
M agent.createConnection(options[, callback])
自 v0.11.4 版本开始新增
options
Object
Options containing connection details. Checknet.createConnection()
for the format of the optionscallback
Function
Callback function that receives the created socket- Returns:
stream.Duplex
Produces a socket/stream to be used for HTTP requests.
By default, this function is the same as net.createConnection()
. However,
custom agents may override this method in case greater flexibility is desired.
A socket/stream can be supplied in one of two ways: by returning the
socket/stream from this function, or by passing the socket/stream to callback
.
This method is guaranteed to return an instance of the net.Socket
class,
a subclass of stream.Duplex
, unless the user specifies a socket
type other than net.Socket
.
callback
has a signature of (err, stream)
.
M agent.keepSocketAlive(socket)
自 v8.1.0 版本开始新增
socket
stream.Duplex
Called when socket
is detached from a request and could be persisted by the
Agent
. Default behavior is to:
JS
This method can be overridden by a particular Agent
subclass. If this
method returns a falsy value, the socket will be destroyed instead of persisting
it for use with the next request.
The socket
argument can be an instance of net.Socket
, a subclass of
stream.Duplex
.
M agent.reuseSocket(socket, request)
自 v8.1.0 版本开始新增
socket
stream.Duplex
request
http.ClientRequest
Called when socket
is attached to request
after being persisted because of
the keep-alive options. Default behavior is to:
JS
This method can be overridden by a particular Agent
subclass.
The socket
argument can be an instance of net.Socket
, a subclass of
stream.Duplex
.
M agent.destroy()
自 v0.11.4 版本开始新增
Destroy any sockets that are currently in use by the agent.
It is usually not necessary to do this. However, if using an
agent with keepAlive
enabled, then it is best to explicitly shut down
the agent when it is no longer needed. Otherwise,
sockets might stay open for quite a long time before the server
terminates them.
M agent.freeSockets
历史
版本 | 历史变更 |
---|---|
v16.0.0 | The property now has a `null` prototype. |
v0.11.4 | 自 v0.11.4 版本开始新增 |
An object which contains arrays of sockets currently awaiting use by
the agent when keepAlive
is enabled. Do not modify.
Sockets in the freeSockets
list will be automatically destroyed and
removed from the array on 'timeout'
.
M agent.getName([options])
历史
版本 | 历史变更 |
---|---|
v17.7.0 | The `options` parameter is now optional. |
v0.11.4 | 自 v0.11.4 版本开始新增 |
Get a unique name for a set of request options, to determine whether a
connection can be reused. For an HTTP agent, this returns
host:port:localAddress
or host:port:localAddress:family
. For an HTTPS agent,
the name includes the CA, cert, ciphers, and other HTTPS/TLS-specific options
that determine socket reusability.
M agent.maxFreeSockets
自 v0.11.7 版本开始新增
By default set to 256. For agents with keepAlive
enabled, this
sets the maximum number of sockets that will be left open in the free
state.
M agent.maxSockets
自 v0.3.6 版本开始新增
By default set to Infinity
. Determines how many concurrent sockets the agent
can have open per origin. Origin is the returned value of agent.getName()
.
M agent.maxTotalSockets
自 v14.5.0, v12.19.0 版本开始新增
By default set to Infinity
. Determines how many concurrent sockets the agent
can have open. Unlike maxSockets
, this parameter applies across all origins.
M agent.requests
历史
版本 | 历史变更 |
---|---|
v16.0.0 | The property now has a `null` prototype. |
v0.5.9 | 自 v0.5.9 版本开始新增 |
An object which contains queues of requests that have not yet been assigned to sockets. Do not modify.
M agent.sockets
历史
版本 | 历史变更 |
---|---|
v16.0.0 | The property now has a `null` prototype. |
v0.3.6 | 自 v0.3.6 版本开始新增 |
An object which contains arrays of sockets currently in use by the agent. Do not modify.
C http.ClientRequest
自 v0.1.17 版本开始新增
- Extends:
http.OutgoingMessage
This object is created internally and returned from http.request()
. It
represents an in-progress request whose header has already been queued. The
header is still mutable using the setHeader(name, value)
,
getHeader(name)
, removeHeader(name)
API. The actual header will
be sent along with the first data chunk or when calling request.end()
.
To get the response, add a listener for 'response'
to the request object.
'response'
will be emitted from the request object when the response
headers have been received. The 'response'
event is executed with one
argument which is an instance of http.IncomingMessage
.
During the 'response'
event, one can add listeners to the
response object; particularly to listen for the 'data'
event.
If no 'response'
handler is added, then the response will be
entirely discarded. However, if a 'response'
event handler is added,
then the data from the response object must be consumed, either by
calling response.read()
whenever there is a 'readable'
event, or
by adding a 'data'
handler, or by calling the .resume()
method.
Until the data is consumed, the 'end'
event will not fire. Also, until
the data is read it will consume memory that can eventually lead to a
'process out of memory' error.
For backward compatibility, res
will only emit 'error'
if there is an
'error'
listener registered.
Set Content-Length
header to limit the response body size. Mismatching the
Content-Length
header value will result in an [Error
][] being thrown,
identified by code:
'ERR_HTTP_CONTENT_LENGTH_MISMATCH'
.
Content-Length
value should be in bytes, not characters. Use
Buffer.byteLength()
to determine the length of the body in bytes.
E 'abort'
自 v17.0.0, v16.12.0 版本开始弃用
Emitted when the request has been aborted by the client. This event is only
emitted on the first call to abort()
.
E 'close'
自 v0.5.4 版本开始新增
Indicates that the request is completed, or its underlying connection was terminated prematurely (before the response completion).
E 'connect'
自 v0.7.0 版本开始新增
response
http.IncomingMessage
socket
stream.Duplex
head
Buffer
Emitted each time a server responds to a request with a CONNECT
method. If
this event is not being listened for, clients receiving a CONNECT
method will
have their connections closed.
This event is guaranteed to be passed an instance of the net.Socket
class,
a subclass of stream.Duplex
, unless the user specifies a socket
type other than net.Socket
.
A client and server pair demonstrating how to listen for the 'connect'
event:
JS
E 'continue'
自 v0.3.2 版本开始新增
Emitted when the server sends a '100 Continue' HTTP response, usually because the request contained 'Expect: 100-continue'. This is an instruction that the client should send the request body.
E 'finish'
自 v0.3.6 版本开始新增
Emitted when the request has been sent. More specifically, this event is emitted when the last segment of the response headers and body have been handed off to the operating system for transmission over the network. It does not imply that the server has received anything yet.
E 'information'
自 v10.0.0 版本开始新增
info
Object
Emitted when the server sends a 1xx intermediate response (excluding 101 Upgrade). The listeners of this event will receive an object containing the HTTP version, status code, status message, key-value headers object, and array with the raw header names followed by their respective values.
JS
101 Upgrade statuses do not fire this event due to their break from the
traditional HTTP request/response chain, such as web sockets, in-place TLS
upgrades, or HTTP 2.0. To be notified of 101 Upgrade notices, listen for the
'upgrade'
event instead.
E 'response'
自 v0.1.0 版本开始新增
response
http.IncomingMessage
Emitted when a response is received to this request. This event is emitted only once.
E 'socket'
自 v0.5.3 版本开始新增
socket
stream.Duplex
This event is guaranteed to be passed an instance of the net.Socket
class,
a subclass of stream.Duplex
, unless the user specifies a socket
type other than net.Socket
.
E 'timeout'
自 v0.7.8 版本开始新增
Emitted when the underlying socket times out from inactivity. This only notifies that the socket has been idle. The request must be destroyed manually.
See also: request.setTimeout()
.
E 'upgrade'
自 v0.1.94 版本开始新增
response
http.IncomingMessage
socket
stream.Duplex
head
Buffer
Emitted each time a server responds to a request with an upgrade. If this event is not being listened for and the response status code is 101 Switching Protocols, clients receiving an upgrade header will have their connections closed.
This event is guaranteed to be passed an instance of the net.Socket
class,
a subclass of stream.Duplex
, unless the user specifies a socket
type other than net.Socket
.
A client server pair demonstrating how to listen for the 'upgrade'
event.
JS
M request.abort()
自 v14.1.0, v13.14.0 版本开始弃用
Marks the request as aborting. Calling this will cause remaining data in the response to be dropped and the socket to be destroyed.
M request.aborted
历史
版本 | 历史变更 |
---|---|
v11.0.0 | The `aborted` property is no longer a timestamp number. |
v17.0.0, v16.12.0 | 自 v17.0.0, v16.12.0 版本开始新增 |
The request.aborted
property will be true
if the request has
been aborted.
M request.connection
自 v13.0.0 版本开始弃用
See request.socket
.
M request.cork()
自 v13.2.0, v12.16.0 版本开始新增
See writable.cork()
.
M request.end([data[, encoding]][, callback])
历史
版本 | 历史变更 |
---|---|
v10.0.0 | This method now returns a reference to `ClientRequest`. |
v0.1.90 | 自 v0.1.90 版本开始新增 |
Finishes sending the request. If any parts of the body are
unsent, it will flush them to the stream. If the request is
chunked, this will send the terminating '0\r\n\r\n'
.
If data
is specified, it is equivalent to calling
request.write(data, encoding)
followed by request.end(callback)
.
If callback
is specified, it will be called when the request stream
is finished.
M request.destroy([error])
历史
版本 | 历史变更 |
---|---|
v14.5.0 | The function returns `this` for consistency with other Readable streams. |
v0.3.0 | 自 v0.3.0 版本开始新增 |
Destroy the request. Optionally emit an 'error'
event,
and emit a 'close'
event. Calling this will cause remaining data
in the response to be dropped and the socket to be destroyed.
See writable.destroy()
for further details.
M request.destroyed
自 v14.1.0, v13.14.0 版本开始新增
Is true
after request.destroy()
has been called.
See writable.destroyed
for further details.
M request.finished
自 v13.4.0, v12.16.0 版本开始弃用
The request.finished
property will be true
if request.end()
has been called. request.end()
will automatically be called if the
request was initiated via http.get()
.
M request.flushHeaders()
自 v1.6.0 版本开始新增
Flushes the request headers.
For efficiency reasons, Node.js normally buffers the request headers until
request.end()
is called or the first chunk of request data is written. It
then tries to pack the request headers and data into a single TCP packet.
That's usually desired (it saves a TCP round-trip), but not when the first
data is not sent until possibly much later. request.flushHeaders()
bypasses
the optimization and kickstarts the request.
M request.getHeader(name)
自 v1.6.0 版本开始新增
Reads out a header on the request. The name is case-insensitive.
The type of the return value depends on the arguments provided to
request.setHeader()
.
JS
M request.getHeaderNames()
自 v7.7.0 版本开始新增
- Returns: string[]
Returns an array containing the unique names of the current outgoing headers. All header names are lowercase.
JS
M request.getHeaders()
自 v7.7.0 版本开始新增
- Returns:
Object
Returns a shallow copy of the current outgoing headers. Since a shallow copy is used, array values may be mutated without additional calls to various header-related http module methods. The keys of the returned object are the header names and the values are the respective header values. All header names are lowercase.
The object returned by the request.getHeaders()
method does not
prototypically inherit from the JavaScript Object
. This means that typical
Object
methods such as obj.toString()
, obj.hasOwnProperty()
, and others
are not defined and will not work.
JS
M request.getRawHeaderNames()
自 v15.13.0, v14.17.0 版本开始新增
- Returns: string[]
Returns an array containing the unique names of the current outgoing raw headers. Header names are returned with their exact casing being set.
JS
M request.hasHeader(name)
自 v7.7.0 版本开始新增
Returns true
if the header identified by name
is currently set in the
outgoing headers. The header name matching is case-insensitive.
JS
M request.maxHeadersCount
number
Default:2000
Limits maximum response headers count. If set to 0, no limit will be applied.
M request.path
自 v0.4.0 版本开始新增
string
The request path.
M request.method
自 v0.1.97 版本开始新增
string
The request method.
M request.host
自 v14.5.0, v12.19.0 版本开始新增
string
The request host.
M request.protocol
自 v14.5.0, v12.19.0 版本开始新增
string
The request protocol.
M request.removeHeader(name)
自 v1.6.0 版本开始新增
name
string
Removes a header that's already defined into headers object.
JS
M request.reusedSocket
自 v13.0.0, v12.16.0 版本开始新增
boolean
Whether the request is send through a reused socket.
When sending request through a keep-alive enabled agent, the underlying socket might be reused. But if server closes connection at unfortunate time, client may run into a 'ECONNRESET' error.
JS
By marking a request whether it reused socket or not, we can do automatic error retry base on it.
JS
M request.setHeader(name, value)
自 v1.6.0 版本开始新增
Sets a single header value for headers object. If this header already exists in
the to-be-sent headers, its value will be replaced. Use an array of strings
here to send multiple headers with the same name. Non-string values will be
stored without modification. Therefore, request.getHeader()
may return
non-string values. However, the non-string values will be converted to strings
for network transmission.
JS
or
JS
When the value is a string an exception will be thrown if it contains
characters outside the latin1
encoding.
If you need to pass UTF-8 characters in the value please encode the value using the RFC 8187 standard.
JS
M request.setNoDelay([noDelay])
自 v0.5.9 版本开始新增
noDelay
boolean
Once a socket is assigned to this request and is connected
socket.setNoDelay()
will be called.
M request.setSocketKeepAlive([enable][, initialDelay])
自 v0.5.9 版本开始新增
Once a socket is assigned to this request and is connected
socket.setKeepAlive()
will be called.
M request.setTimeout(timeout[, callback])
历史
版本 | 历史变更 |
---|---|
v9.0.0 | Consistently set socket timeout only when the socket connects. |
v0.5.9 | 自 v0.5.9 版本开始新增 |
timeout
number
Milliseconds before a request times out.callback
Function
Optional function to be called when a timeout occurs. Same as binding to the'timeout'
event.- Returns:
http.ClientRequest
Once a socket is assigned to this request and is connected
socket.setTimeout()
will be called.
M request.socket
自 v0.3.0 版本开始新增
Reference to the underlying socket. Usually users will not want to access
this property. In particular, the socket will not emit 'readable'
events
because of how the protocol parser attaches to the socket.
JS
This property is guaranteed to be an instance of the net.Socket
class,
a subclass of stream.Duplex
, unless the user specified a socket
type other than net.Socket
.
M request.uncork()
自 v13.2.0, v12.16.0 版本开始新增
See writable.uncork()
.
M request.writableEnded
自 v12.9.0 版本开始新增
Is true
after request.end()
has been called. This property
does not indicate whether the data has been flushed, for this use
request.writableFinished
instead.
M request.writableFinished
自 v12.7.0 版本开始新增
Is true
if all data has been flushed to the underlying system, immediately
before the 'finish'
event is emitted.
M request.write(chunk[, encoding][, callback])
自 v0.1.29 版本开始新增
Sends a chunk of the body. This method can be called multiple times. If no
Content-Length
is set, data will automatically be encoded in HTTP Chunked
transfer encoding, so that server knows when the data ends. The
Transfer-Encoding: chunked
header is added. Calling request.end()
is necessary to finish sending the request.
The encoding
argument is optional and only applies when chunk
is a string.
Defaults to 'utf8'
.
The callback
argument is optional and will be called when this chunk of data
is flushed, but only if the chunk is non-empty.
Returns true
if the entire data was flushed successfully to the kernel
buffer. Returns false
if all or part of the data was queued in user memory.
'drain'
will be emitted when the buffer is free again.
When write
function is called with empty string or buffer, it does
nothing and waits for more input.
C http.Server
自 v0.1.17 版本开始新增
- Extends:
net.Server
E 'checkContinue'
自 v0.3.0 版本开始新增
request
http.IncomingMessage
response
http.ServerResponse
Emitted each time a request with an HTTP Expect: 100-continue
is received.
If this event is not listened for, the server will automatically respond
with a 100 Continue
as appropriate.
Handling this event involves calling response.writeContinue()
if the
client should continue to send the request body, or generating an appropriate
HTTP response (e.g. 400 Bad Request) if the client should not continue to send
the request body.
When this event is emitted and handled, the 'request'
event will
not be emitted.
E 'checkExpectation'
自 v5.5.0 版本开始新增
request
http.IncomingMessage
response
http.ServerResponse
Emitted each time a request with an HTTP Expect
header is received, where the
value is not 100-continue
. If this event is not listened for, the server will
automatically respond with a 417 Expectation Failed
as appropriate.
When this event is emitted and handled, the 'request'
event will
not be emitted.
E 'clientError'
历史
版本 | 历 史变更 |
---|---|
v12.0.0 | The default behavior will return a 431 Request Header Fields Too Large if a HPE_HEADER_OVERFLOW error occurs. |
v9.4.0 | The `rawPacket` is the current buffer that just parsed. Adding this buffer to the error object of `'clientError'` event is to make it possible that developers can log the broken packet. |
v6.0.0 | The default action of calling `.destroy()` on the `socket` will no longer take place if there are listeners attached for `'clientError'`. |
v0.1.94 | 自 v0.1.94 版本开始新增 |
exception
Error
socket
stream.Duplex
If a client connection emits an 'error'
event, it will be forwarded here.
Listener of this event is responsible for closing/destroying the underlying
socket. For example, one may wish to more gracefully close the socket with a
custom HTTP response instead of abruptly severing the connection.
This event is guaranteed to be passed an instance of the net.Socket
class,
a subclass of stream.Duplex
, unless the user specifies a socket
type other than net.Socket
.
Default behavior is to try close the socket with a HTTP '400 Bad Request',
or a HTTP '431 Request Header Fields Too Large' in the case of a
HPE_HEADER_OVERFLOW
error. If the socket is not writable or headers
of the current attached http.ServerResponse
has been sent, it is
immediately destroyed.
socket
is the net.Socket
object that the error originated from.
JS
When the 'clientError'
event occurs, there is no request
or response
object, so any HTTP response sent, including response headers and payload,
must be written directly to the socket
object. Care must be taken to
ensure the response is a properly formatted HTTP response message.
err
is an instance of Error
with two extra columns:
bytesParsed
: the bytes count of request packet that Node.js may have parsed correctly;rawPacket
: the raw packet of current request.
In some cases, the client has already received the response and/or the socket
has already been destroyed, like in case of ECONNRESET
errors. Before
trying to send data to the socket, it is better to check that it is still
writable.
JS
E 'close'
自 v0.1.4 版本开始新增
Emitted when the server closes.
E 'connect'
自 v0.7.0 版本开始新增
request
http.IncomingMessage
Arguments for the HTTP request, as it is in the'request'
eventsocket
stream.Duplex
Network socket between the server and clienthead
Buffer
The first packet of the tunneling stream (may be empty)
Emitted each time a client requests an HTTP CONNECT
method. If this event is
not listened for, then clients requesting a CONNECT
method will have their
connections closed.
This event is guaranteed to be passed an instance of the net.Socket
class,
a subclass of stream.Duplex
, unless the user specifies a socket
type other than net.Socket
.
After this event is emitted, the request's socket will not have a 'data'
event listener, meaning it will need to be bound in order to handle data
sent to the server on that socket.
E 'connection'
自 v0.1.0 版本开始新增
socket
stream.Duplex
This event is emitted when a new TCP stream is established. socket
is
typically an object of type net.Socket
. Usually users will not want to
access this event. In particular, the socket will not emit 'readable'
events
because of how the protocol parser attaches to the socket. The socket
can
also be accessed at request.socket
.
This event can also be explicitly emitted by users to inject connections
into the HTTP server. In that case, any Duplex
stream can be passed.
If socket.setTimeout()
is called here, the timeout will be replaced with
server.keepAliveTimeout
when the socket has served a request (if
server.keepAliveTimeout
is non-zero).
This event is guaranteed to be passed an instance of the net.Socket
class,
a subclass of stream.Duplex
, unless the user specifies a socket
type other than net.Socket
.
E 'dropRequest'
自 v18.7.0 版本开始新增
request
http.IncomingMessage
Arguments for the HTTP request, as it is in the'request'
eventsocket
stream.Duplex
Network socket between the server and client
When the number of requests on a socket reaches the threshold of
server.maxRequestsPerSocket
, the server will drop new requests
and emit 'dropRequest'
event instead, then send 503
to client.
E 'request'
自 v0.1.0 版本开始新增
request
http.IncomingMessage
response
http.ServerResponse
Emitted each time there is a request. There may be multiple requests per connection (in the case of HTTP Keep-Alive connections).
E 'upgrade'
历史
版本 | 历史变更 |
---|---|
v10.0.0 | Not listening to this event no longer causes the socket to be destroyed if a client sends an Upgrade header. |
v0.1.94 | 自 v0.1.94 版本开始新增 |
request
http.IncomingMessage
Arguments for the HTTP request, as it is in the'request'
eventsocket
stream.Duplex
Network socket between the server and clienthead
Buffer
The first packet of the upgraded stream (may be empty)
Emitted each time a client requests an HTTP upgrade. Listening to this event is optional and clients cannot insist on a protocol change.
After this event is emitted, the request's socket will not have a 'data'
event listener, meaning it will need to be bound in order to handle data
sent to the server on that socket.
This event is guaranteed to be passed an instance of the net.Socket
class,
a subclass of stream.Duplex
, unless the user specifies a socket
type other than net.Socket
.
M server.close([callback])
自 v0.1.90 版本开始新增
callback
Function
Stops the server from accepting new connections. See net.Server.close()
.
M server.closeAllConnections()
自 v18.2.0 版本开始新增
Closes all connections connected to this server.
M server.closeIdleConnections()
自 v18.2.0 版本开始新增
Closes all connections connected to this server which are not sending a request or waiting for a response.
M server.headersTimeout
自 v11.3.0, v10.14.0 版本开始新增
number
Default:60000
Limit the amount of time the parser will wait to receive the complete HTTP headers.
If the timeout expires, the server responds with status 408 without forwarding the request to the request listener and then closes the connection.
It must be set to a non-zero value (e.g. 120 seconds) to protect against potential Denial-of-Service attacks in case the server is deployed without a reverse proxy in front.
M server.listen()
Starts the HTTP server listening for connections.
This method is identical to server.listen()
from net.Server
.
M server.listening
自 v5.7.0 版本开始新增
boolean
Indicates whether or not the server is listening for connections.
M server.maxHeadersCount
自 v0.7.0 版本开始新增
number
Default:2000
Limits maximum incoming headers count. If set to 0, no limit will be applied.
M server.requestTimeout
历史
版本 | 历史变更 |
---|---|
v18.0.0 | The default request timeout changed from no timeout to 300s (5 minutes). |
v14.11.0 | 自 v14.11.0 版本开始新增 |
number
Default:300000
Sets the timeout value in milliseconds for receiving the entire request from the client.
If the timeout expires, the server responds with status 408 without forwarding the request to the request listener and then closes the connection.
It must be set to a non-zero value (e.g. 120 seconds) to protect against potential Denial-of-Service attacks in case the server is deployed without a reverse proxy in front.
M server.setTimeout([msecs][, callback])
历史
版本 | 历史变更 |
---|---|
v13.0.0 | The default timeout changed from 120s to 0 (no timeout). |
v0.9.12 | 自 v0.9.12 版本开始新增 |
msecs
number
Default: 0 (no timeout)callback
Function
- Returns:
http.Server
Sets the timeout value for sockets, and emits a 'timeout'
event on
the Server object, passing the socket as an argument, if a timeout
occurs.
If there is a 'timeout'
event listener on the Server object, then it
will be called with the timed-out socket as an argument.
By default, the Server does not timeout sockets. However, if a callback
is assigned to the Server's 'timeout'
event, timeouts must be handled
explicitly.
M server.maxRequestsPerSocket
自 v16.10.0 版本开始新增
number
Requests per socket. Default: 0 (no limit)
The maximum number of requests socket can handle before closing keep alive connection.
A value of 0
will disable the limit.
When the limit is reached it will set the Connection
header value to close
,
but will not actually close the connection, subsequent requests sent
after the limit is reached will get 503 Service Unavailable
as a response.
M server.timeout
历史
版本 | 历史变更 |
---|---|
v13.0.0 | The default timeout changed from 120s to 0 (no timeout). |
v0.9.12 | 自 v0.9.12 版本开始新增 |
number
Timeout in milliseconds. Default: 0 (no timeout)
The number of milliseconds of inactivity before a socket is presumed to have timed out.
A value of 0
will disable the timeout behavior on incoming connections.
The socket timeout logic is set up on connection, so changing this value only affects new connections to the server, not any existing connections.
M server.keepAliveTimeout
自 v8.0.0 版本开始新增
number
Timeout in milliseconds. Default:5000
(5 seconds).
The number of milliseconds of inactivity a server needs to wait for additional
incoming data, after it has finished writing the last response, before a socket
will be destroyed. If the server receives new data before the keep-alive
timeout has fired, it will reset the regular inactivity timeout, i.e.,
server.timeout
.
A value of 0
will disable the keep-alive timeout behavior on incoming
connections.
A value of 0
makes the http server behave similarly to Node.js versions prior
to 8.0.0, which did not have a keep-alive timeout.
The socket timeout logic is set up on connection, so changing this value only affects new connections to the server, not any existing connections.
C http.ServerResponse
自 v0.1.17 版本开始新增
- Extends:
http.OutgoingMessage
This object is created internally by an HTTP server, not by the user. It is
passed as the second parameter to the 'request'
event.
E 'close'
自 v0.6.7 版本开始新增
Indicates that the response is completed, or its underlying connection was terminated prematurely (before the response completion).
E 'finish'
自 v0.3.6 版本开始新增
Emitted when the response has been sent. More specifically, this event is emitted when the last segment of the response headers and body have been handed off to the operating system for transmission over the network. It does not imply that the client has received anything yet.
M response.addTrailers(headers)
自 v0.3.0 版本开始新增
headers
Object
This method adds HTTP trailing headers (a header but at the end of the message) to the response.
Trailers will only be emitted if chunked encoding is used for the response; if it is not (e.g. if the request was HTTP/1.0), they will be silently discarded.
HTTP requires the Trailer
header to be sent in order to
emit trailers, with a list of the header fields in its value. E.g.,
JS
Attempting to set a header field name or value that contains invalid characters
will result in a TypeError
being thrown.
M response.connection
自 v13.0.0 版本开始弃用
See response.socket
.
M response.cork()
自 v13.2.0, v12.16.0 版本开始新增
See writable.cork()
.
M response.end([data[, encoding]][, callback])
历史
版本 | 历史变更 |
---|---|
v10.0.0 | This method now returns a reference to `ServerResponse`. |
v0.1.90 | 自 v0.1.90 版本开始新增 |
This method signals to the server that all of the response headers and body
have been sent; that server should consider this message complete.
The method, response.end()
, MUST be called on each response.
If data
is specified, it is similar in effect to calling
response.write(data, encoding)
followed by response.end(callback)
.
If callback
is specified, it will be called when the response stream
is finished.
M response.finished
自 v13.4.0, v12.16.0 版本开始弃用
The response.finished
property will be true
if response.end()
has been called.
M response.flushHeaders()
自 v1.6.0 版本开始新增
Flushes the response headers. See also: request.flushHeaders()
.
M response.getHeader(name)
自 v0.4.0 版本开始新增
Reads out a header that's already been queued but not sent to the client.
The name is case-insensitive. The type of the return value depends
on the arguments provided to response.setHeader()
.
JS
M response.getHeaderNames()
自 v7.7.0 版本开始新增
- Returns: string[]
Returns an array containing the unique names of the current outgoing headers. All header names are lowercase.
JS
M response.getHeaders()
自 v7.7.0 版本开始新增
- Returns:
Object
Returns a shallow copy of the current outgoing headers. Since a shallow copy is used, array values may be mutated without additional calls to various header-related http module methods. The keys of the returned object are the header names and the values are the respective header values. All header names are lowercase.
The object returned by the response.getHeaders()
method does not
prototypically inherit from the JavaScript Object
. This means that typical
Object
methods such as obj.toString()
, obj.hasOwnProperty()
, and others
are not defined and will not work.
JS
M response.hasHeader(name)
自 v7.7.0 版本开始新增
Returns true
if the header identified by name
is currently set in the
outgoing headers. The header name matching is case-insensitive.
JS
M response.headersSent
自 v0.9.3 版本开始新增
Boolean (read-only). True if headers were sent, false otherwise.
M response.removeHeader(name)
自 v0.4.0 版本开始新增
name
string
Removes a header that's queued for implicit sending.
JS
M response.req
自 v15.7.0 版本开始新增
A reference to the original HTTP request
object.
M response.sendDate
自 v0.7.5 版本开始新增
When true, the Date header will be automatically generated and sent in the response if it is not already present in the headers. Defaults to true.
This should only be disabled for testing; HTTP requires the Date header in responses.
M response.setHeader(name, value)
自 v0.4.0 版本开始新增
name
string
value
any
- Returns:
http.ServerResponse
Returns the response object.
Sets a single header value for implicit headers. If this header already exists
in the to-be-sent headers, its value will be replaced. Use an array of strings
here to send multiple headers with the same name. Non-string values will be
stored without modification. Therefore, response.getHeader()
may return
non-string values. However, the non-string values will be converted to strings
for network transmission. The same response object is returned to the caller,
to enable call chaining.
JS
or
JS
Attempting to set a header field name or value that contains invalid characters
will result in a TypeError
being thrown.
When headers have been set with response.setHeader()
, they will be merged
with any headers passed to response.writeHead()
, with the headers passed
to response.writeHead()
given precedence.
JS
If response.writeHead()
method is called and this method has not been
called, it will directly write the supplied header values onto the network
channel without caching internally, and the response.getHeader()
on the
header will not yield the expected result. If progressive population of headers
is desired with potential future retrieval and modification, use
response.setHeader()
instead of response.writeHead()
.
M response.setTimeout(msecs[, callback])
自 v0.9.12 版本开始新增
msecs
number
callback
Function
- Returns:
http.ServerResponse
Sets the Socket's timeout value to msecs
. If a callback is
provided, then it is added as a listener on the 'timeout'
event on
the response object.
If no 'timeout'
listener is added to the request, the response, or
the server, then sockets are destroyed when they time out. If a handler is
assigned to the request, the response, or the server's 'timeout'
events,
timed out sockets must be handled explicitly.
M response.socket
自 v0.3.0 版本开始新增
Reference to the underlying socket. Usually users will not want to access
this property. In particular, the socket will not emit 'readable'
events
because of how the protocol parser attaches to the socket. After
response.end()
, the property is nulled.
JS
This property is guaranteed to be an instance of the net.Socket
class,
a subclass of stream.Duplex
, unless the user specified a socket
type other than net.Socket
.
M response.statusCode
自 v0.4.0 版本开始新增
number
Default:200
When using implicit headers (not calling response.writeHead()
explicitly),
this property controls the status code that will be sent to the client when
the headers get flushed.
JS
After response header was sent to the client, this property indicates the status code which was sent out.
M response.statusMessage
自 v0.11.8 版本开始新增
When using implicit headers (not calling response.writeHead()
explicitly),
this property controls the status message that will be sent to the client when
the headers get flushed. If this is left as undefined
then the standard
message for the status code will be used.
JS
After response header was sent to the client, this property indicates the status message which was sent out.
M response.uncork()
自 v13.2.0, v12.16.0 版本开始新增
See writable.uncork()
.
M response.writableEnded
自 v12.9.0 版本开始新增
Is true
after response.end()
has been called. This property
does not indicate whether the data has been flushed, for this use
response.writableFinished
instead.
M response.writableFinished
自 v12.7.0 版本开始新增
Is true
if all data has been flushed to the underlying system, immediately
before the 'finish'
event is emitted.
M response.write(chunk[, encoding][, callback])
自 v0.1.29 版本开始新增
If this method is called and response.writeHead()
has not been called,
it will switch to implicit header mode and flush the implicit headers.
This sends a chunk of the response body. This method may be called multiple times to provide successive parts of the body.
In the node:http
module, the response body is omitted when the
request is a HEAD request. Similarly, the 204
and 304
responses
must not include a message body.
chunk
can be a string or a buffer. If chunk
is a string,
the second parameter specifies how to encode it into a byte stream.
callback
will be called when this chunk of data is flushed.
This is the raw HTTP body and has nothing to do with higher-level multi-part body encodings that may be used.
The first time response.write()
is called, it will send the buffered
header information and the first chunk of the body to the client. The second
time response.write()
is called, Node.js assumes data will be streamed,
and sends the new data separately. That is, the response is buffered up to the
first chunk of the body.
Returns true
if the entire data was flushed successfully to the kernel
buffer. Returns false
if all or part of the data was queued in user memory.
'drain'
will be emitted when the buffer is free again.
M response.writeContinue()
自 v0.3.0 版本开始新增
Sends an HTTP/1.1 100 Continue message to the client, indicating that
the request body should be sent. See the 'checkContinue'
event on
Server
.
M response.writeEarlyHints(hints[, callback])
历史
版本 | 历史变更 |
---|---|
v18.11.0 | Allow passing hints as an object. |
v18.11.0 | 自 v18.11.0 版本开始新增 |
Sends an HTTP/1.1 103 Early Hints message to the client with a Link header,
indicating that the user agent can preload/preconnect the linked resources.
The hints
is an object containing the values of headers to be sent with
early hints message. The optional callback
argument will be called when
the response message has been written.
Example
JS