app.locals(obj) (app.locals({ foo: 'bar', bar: 'baz'}))
app.render(name[, options], callback) to render app-level views
app.engine(ext, callback) to map template engines
Settings
trust proxy setting enables the use of “X-Forwarded-Proto” for req.protocol and res.redirect url construction
json spaces setting enables the developer to decide if res.json() responds with nicely formatted JSON or compact json (this value is passed to JSON.stringify())
json replacer setting is a callback which is passed to JSON.stringify() in res.json() allowing you to manipulate and filter the JSON response
Request
req.path the request pathname
req.protocol returns the protocol string “http” or “https” (supports X-Forwarded-Proto via trust proxy setting)
req.get(field) gets a request header field value (req.get('Host'))
req.accepts(type) improved
req.accepts(types) added, returns the most viable type
req.accepted array of parsed Accept values sorted by quality
req.acceptsCharset(charset) added
req.acceptedCharsets array of parsed Accept-Charset values sorted by quality
req.acceptsLanguage(lang) added
req.acceptedLanguages array of parsed Accept-Language values sorted by quality
req.signedCookies object containing signed cookies
req.stale to see if a request is stale (based on ETag/Last-Modified)
req.fresh to complement req.stale
req.ips to return an array of X-Forwarded-For values when “trust proxy” is enabled
req.ip return the upstream addr in req.ips or req.connection.remoteAddress
req.range(size) parses the Range header field
Response
res.get(field) gets a response header field value (res.get('Content-Length'))
res.set(field, value) sets a response header field (res.set('Content-Length', n))
res.set(obj) set several field values
res.type(path) alias of previous res.contentType(path), allows res.type('json'), res.type('application/x-whatever')
res.format(obj) to format responses based on qvalue-sorted Accept
JSON cookie support (res.cookie('cart', { ids: [1,2,3] }), req.cookies.cart.ids)
signed cookie support (res.cookie(name, value, { signed: true }))
res.format(obj) for content-negotiation
res.locals object (res.locals.foo = 'bar')
res.locals(obj) (res.locals({ foo: 'bar', bar: 'baz'))
res.redirect() X-Forwarded-Proto support
res.redirect() relative support (res.redirect('../new'), res.redirect('./edit'), etc)
res.links(obj) set the “Link” header field with the given links
res.jsonp([status], obj) was added for explicit JSONP support
