Fired when the HTTP response headers for a request are received. Use this event to modify HTTP response headers.
To have the response headers passed into the listener, along with the rest of the request data, pass
"responseHeaders"
在
extraInfoSpec
数组。
若使用
"blocking"
, you must have the
"webRequestBlocking" API permission
in your manifest.json.
It is possible for extensions to make conflicting requests. If two extensions listen to
onHeadersReceived
for the same request and return
responseHeaders
to set the same header (for example,
Set-Cookie
) not present in the original response, only one of the changes will succeed.
不管怎样，
Content-Security-Policy
header is treated differently; its values are combined to apply all the specified policies. But, if two extensions set a CSP value that conflicts, the CSP service makes the restriction more strict to resolve the conflict. For example, if one extension sets
img-src: example.com
, and another extension sets
img-src: example.org
, the result is
img-src: 'none'
. Merged modifications always lean towards being more restrictive, though an extension may remove the original CSP header.
If you want to see the headers that are processed by the system, without the risk that another extension will alter them, use
webRequest.onResponseStarted
, although you can't modify headers on this event.
browser.webRequest.onHeadersReceived.addListener(
listener
,
// function
filter
,
// object
extraInfoSpec
// optional array of strings
)
浏览器
.
webRequest
.
onHeadersReceived
.
removeListener
(
listener
)
浏览器
.
webRequest
.
onHeadersReceived
.
hasListener
(
listener
)
Events have three functions:
addListener(callback, filter, extraInfoSpec)
Adds a listener to this event.
removeListener(listener)
Stop listening to this event. The
listener
argument is the listener to remove.
hasListener(listener)
校验是否
listener
is registered for this event. Returns
true
if it is listening,
false
否则。
callback
The function called when this event occurs. The function is passed the following arguments:
details
对象
. Details of the request. This will include response headers if you have included
"responseHeaders"
in
extraInfoSpec
.
返回：
webRequest.BlockingResponse
。若
"blocking"
is specified in the
extraInfoSpec
parameter, the event listener will return a
BlockingResponse
object, and can set its
responseHeaders
property. In Firefox, the return value can be a
Promise
that resolves to a
BlockingResponse
.
filter
webRequest.RequestFilter
. A set of filters that restricts the events that are sent to this listener.
extraInfoSpec
可选
array
of
string
. Extra options for the event. You can pass any of the following values:
"blocking"
to make the request synchronous, so you can modify request and response headers
"responseHeaders"
to include the response headers in the
details
object passed to the listener
cookieStoreId
string
. If the request is from a tab open in a contextual identity, the cookie store ID of the contextual identity.
documentUrl
string
. URL of the document in which the resource will be loaded. For example, if the web page at "https://example.com" contains an image or an iframe, then the
documentUrl
for the image or iframe will be "https://example.com". For a top-level document,
documentUrl
is undefined.
frameAncestors
array
. Information for each document in the frame hierarchy up to the top-level document. The first element in the array contains information about the immediate parent of the document being requested, and the last element contains information about the top-level document. If the load is for the top-level document, then this array is empty.
url
string
. The URL that the document was loaded from.
frameId
integer
。
frameId
of the document.
details.frameAncestors[0].frameId
如同
details.parentFrameId
.
frameId
integer
. Zero if the request happens in the main frame; a positive value is the ID of a subframe in which the request happens. If the document of a (sub-)frame is loaded (
type
is
main_frame
or
sub_frame
),
frameId
indicates the ID of this frame, not the ID of the outer frame. Frame IDs are unique within a tab.
fromCache
boolean
. Whether the response is fetched from disk cache.
incognito
boolean
. Whether the request is from a private browsing window.
ip
string
. The IP address of the server the request was sent to. It may be a literal IPv6 address.
方法
string
. Standard HTTP method: for example, "GET" or "POST".
originUrl
string
. URL of the resource that triggered the request. For example, if "https://example.com" contains a link, and the user clicks the link, then the
originUrl
for the resulting request is "https://example.com".
originUrl
is often but not always the same as the
documentUrl
. For example, if a page contains an iframe, and the iframe contains a link that loads a new document into the iframe, then the
documentUrl
for the resulting request is the iframe's parent document, but the
originUrl
is the URL of the document in the iframe that contained the link.
parentFrameId
integer
. ID of the frame that contains the frame that sent the request. Set to -1 if no parent frame exists.
proxyInfo
对象
. This property is present only if the request is being proxied. It contains the following properties:
host
string
. The hostname of the proxy server.
port
integer
. The port number of the proxy server.
type
string
. The type of proxy server. One of:
username
string
. Username for the proxy service.
proxyDNS
boolean
. True if the proxy will perform domain name resolution based on the hostname supplied, meaning that the client should not do its own DNS lookup.
failoverTimeout
integer
. Failover timeout in seconds. If the proxy connection fails, the proxy will not be used again for this period.
requestId
string
. The ID of the request. Request IDs are unique within a browser session, so you can use them to relate different events associated with the same request.
responseHeaders
可选
webRequest.HttpHeaders
. The HTTP response headers that were received for this request.
statusCode
integer
. Standard HTTP status code returned by the server.
statusLine
string
. HTTP status line of the response or the 'HTTP/0.9 200 OK' string for HTTP/0.9 responses (that is, responses that lack a status line).
tabId
integer
. ID of the tab in which the request takes place. Set to -1 if the request isn't related to a tab.
thirdParty
boolean
. Indicates whether the request and its content window hierarchy are third party.
timeStamp
编号
. The time when this event fired, in
milliseconds since the epoch
.
type
webRequest.ResourceType
. The type of resource being requested: for example, "image", "script", "stylesheet".
url
string
. Target of the request.
urlClassification
对象
. The type of tracking associated with the request, if with the request has been classified by
Firefox Tracking Protection
. This is an object with the following properties:
firstParty
array
of
strings
. Classification flags for the request's first party.
thirdParty
array
of
strings
. Classification flags for the request or its window hierarchy's third parties.
The classification flags include:
fingerprinting
and
fingerprinting_content
: indicates the request is involved in fingerprinting.
fingerprinting_content
indicates the request is loaded from an origin that has been found to fingerprint but is not considered to participate in tracking, such as a payment provider.
cryptomining
and
cryptomining_content
: similar to the fingerprinting category but for cryptomining resources.
tracking
,
tracking_ad
,
tracking_analytics
,
tracking_social
, and
tracking_content
: indicates the request is involved in tracking.
tracking
is any generic tracking request, the
ad
,
analytics
,
social
，和
content
suffixes identify the type of tracker.
any_basic_tracking
: a meta flag that combines any tracking and fingerprinting flags, excluding
tracking_content
and
fingerprinting_content
.
any_strict_tracking
: a meta flag that combines any tracking and fingerprinting flags, including
tracking_content
and
fingerprinting_content
.
any_social_tracking
: a meta flag that combines any social tracking flags.
BCD tables only load in the browser
This code sets an extra cookie when requesting a resource from the target URL:
var targetPage = "https://developer.mozilla.org/en-US/Firefox/Developer_Edition";
// Add the new header to the original array,
// and return it.
function setCookie(e) {
var setMyCookie = {
name: "Set-Cookie",
value: "my-cookie1=my-cookie-value1"
};
e.responseHeaders.push(setMyCookie);
return {responseHeaders: e.responseHeaders};
}
// Listen for onHeaderReceived for the target page.
// Set "blocking" and "responseHeaders".
browser.webRequest.onHeadersReceived.addListener(
setCookie,
{urls: [targetPage]},
["blocking", "responseHeaders"]
);
This code does the same thing the previous example, except that the listener is asynchronous, returning a
Promise
which is resolved with the new headers:
var targetPage = "https://developer.mozilla.org/en-US/Firefox/Developer_Edition";
// Return a Promise that sets a timer.
// When the timer fires, resolve the promise with
// modified set of response headers.
function setCookieAsync(e) {
var asyncSetCookie = new Promise((resolve, reject) => {
window.setTimeout(() => {
var setMyCookie = {
name: "Set-Cookie",
value: "my-cookie1=my-cookie-value1"
};
e.responseHeaders.push(setMyCookie);
resolve({responseHeaders: e.responseHeaders});
}, 2000);
});
return asyncSetCookie;
}
// Listen for onHeaderReceived for the target page.
// Set "blocking" and "responseHeaders".
browser.webRequest.onHeadersReceived.addListener(
setCookieAsync,
{urls: [targetPage]},
["blocking", "responseHeaders"]
);
注意：
This API is based on Chromium's
chrome.webRequest
API. This documentation is derived from
web_request.json
in the Chromium code.
Microsoft Edge compatibility data is supplied by Microsoft Corporation and is included here under the Creative Commons Attribution 3.0 United States License.
最后修改： , 由 MDN 贡献者