6.7 KiB
Request
A Koa Request object is an abstraction on top of node's vanilla request object,
providing additional functionality that is useful for every day HTTP server
development.
API
req.header
Request header object.
req.method
Request method.
req.method=
Set request method, useful for implementing middleware
such as methodOverride().
req.length
Return request Content-Length as a number when present, or undefined.
req.url
Get request URL.
req.url=
Set request URL, useful for url rewrites.
req.path
Get request pathname.
req.path=
Set request pathname and retain query-string when present.
req.querystring
Get raw query string void of ?.
req.querystring=
Set raw query string.
req.search
Get raw query string with the ?.
req.search=
Set raw query string.
req.host
Get host void of port number when present. Supports X-Forwarded-Host
when app.proxy is true, otherwise Host is used.
req.host=
Set host to a new value. It sets the Host header under the hood and will
behave correctly with req.subdomains.
This can be useful for a hostOverride() middleware
req.type
Get request Content-Type void of parameters such as "charset".
var ct = this.type;
// => "image/png"
req.query
Get parsed query-string, returning an empty object when no query-string is present. Note that this getter does not support nested parsing.
For example "color=blue&size=small":
{
color: 'blue',
size: 'small'
}
req.query=
Set query-string to the given object. Note that this setter does not support nested objects.
this.query = { next: '/login' };
req.fresh
Check if a request cache is "fresh", aka the contents have not changed. This
method is for cache negotiation between If-None-Match / ETag, and If-Modified-Since and Last-Modified. It should be referenced after setting one or more of these response headers.
this.set('ETag', '123');
// cache is ok
if (this.fresh) {
this.status = 304;
return;
}
// cache is stale
// fetch new data
this.body = yield db.find('something');
req.stale
Inverse of req.fresh.
req.protocol
Return request protocol, "https" or "http". Supports X-Forwarded-Proto
when app.proxy is true.
req.secure
Shorthand for this.protocol == "https" to check if a request was
issued via TLS.
req.ip
Request remote address. Supports X-Forwarded-For when app.proxy
is true.
req.ips
When X-Forwarded-For is present and app.proxy is enabled an array
of these ips is returned, ordered from upstream -> downstream. When disabled
an empty array is returned.
req.subdomains
Return subdomains as an array.
Subdomains are the dot-separated parts of the host before the main domain of
the app. By default, the domain of the app is assumed to be the last two
parts of the host. This can be changed by setting app.subdomainOffset.
For example, if the domain is "tobi.ferrets.example.com":
If app.subdomainOffset is not set, this.subdomains is ["ferrets", "tobi"].
If app.subdomainOffset is 3, this.subdomains is ["tobi"].
req.is(type)
Check if the incoming request contains the "Content-Type"
header field, and it contains any of the give mime types.
If there is no request body, undefined is returned.
If there is no content type, or the match fails false is returned.
Otherwise, it returns the matching content-type.
// With Content-Type: text/html; charset=utf-8
this.is('html'); // => 'html'
this.is('text/html'); // => 'text/html'
this.is('text/*', 'text/html'); // => 'text/html'
// When Content-Type is application/json
this.is('json', 'urlencoded'); // => 'json'
this.is('application/json'); // => 'application/json'
this.is('html', 'application/*'); // => 'application/json'
this.is('html'); // => false
For example if you want to ensure that only images are sent to a given route:
if (this.is('image/*')) {
// process
} else {
this.throw(415, 'images only!');
}
req.accepts(types)
Check if the given type(s) is acceptable, returning
the best match when true, otherwise false, in which
case you should respond with 406 "Not Acceptable".
The type value may be one or more mime type string
such as "application/json", the extension name
such as "json", or an array ["json", "html", "text/plain"].
When a list or array is given the best match, if any is returned.
Note that if the client did not send an Accept header,
the first type will be returned.
// Accept: text/html
this.accepts('html');
// => "html"
// Accept: text/*, application/json
this.accepts('html');
// => "html"
this.accepts('text/html');
// => "text/html"
this.accepts('json', 'text');
// => "json"
this.accepts('application/json');
// => "application/json"
// Accept: text/*, application/json
this.accepts('image/png');
this.accepts('png');
// => undefined
// Accept: text/*;q=.5, application/json
this.accepts(['html', 'json']);
this.accepts('html', 'json');
// => "json"
You may call this.accepts() as may times as you like,
or use a switch:
switch (this.accepts('json', 'html', 'text')) {
case 'json': break;
case 'html': break;
case 'text': break;
default: this.throw(406);
}
req.acceptsEncodings(encodings)
Check if encodings are acceptable, returning
the best match when true, otherwise identity.
// Accept-Encoding: gzip
this.acceptsEncodings('gzip', 'deflate');
// => "gzip"
this.acceptsEncodings(['gzip', 'deflate']);
// => "gzip"
When no arguments are given all accepted encodings are returned as an array:
// Accept-Encoding: gzip, deflate
this.acceptsEncodings();
// => ["gzip", "deflate"]
req.acceptsCharsets(charsets)
Check if charsets are acceptable, returning
the best match when true, otherwise undefined.
// Accept-Charset: utf-8, iso-8859-1;q=0.2, utf-7;q=0.5
this.acceptsCharsets('utf-8', 'utf-7');
// => "utf-8"
this.acceptsCharsets(['utf-7', 'utf-8']);
// => "utf-8"
When no arguments are given all accepted charsets are returned as an array:
// Accept-Charset: utf-8, iso-8859-1;q=0.2, utf-7;q=0.5
this.acceptsCharsets();
// => ["utf-8", "utf-7", "iso-8859-1"]
req.acceptsLanguages(langs)
Check if langs are acceptable, returning
the best match when true, otherwise undefined.
// Accept-Language: en;q=0.8, es, pt
this.acceptsLanguages('es', 'en');
// => "es"
this.acceptsLanguages(['en', 'es']);
// => "es"
When no arguments are given all accepted languages are returned as an array:
// Accept-Language: en;q=0.8, es, pt
this.acceptsLanguages();
// => ["es", "pt", "en"]