http - Golang Cookie Max-Age 与过期

Question

Cookie struct 中的 Expires 和 Max-Age 有什么区别？看不懂。

type Cookie struct {
    Name  string
    Value string

    Path       string    // optional
    Domain     string    // optional
    Expires    time.Time // optional
    RawExpires string    // for reading cookies only

    // MaxAge=0 means no 'Max-Age' attribute specified.
    // MaxAge<0 means delete cookie now, equivalently 'Max-Age: 0'
    // MaxAge>0 means Max-Age attribute present and given in seconds
    MaxAge   int
    Secure   bool
    HttpOnly bool
    SameSite SameSite
    Raw      string
    Unparsed []string // Raw text of unparsed attribute-value pairs
}

Answer 1

它们实际上是 Set-Cookie header 的不同字段，并不特定于 Go。

来自 Mozilla docs :

过期

Indicates the maximum lifetime of the cookie as an HTTP-date timestamp. See Date for the required formatting.

If unspecified, the cookie becomes a session cookie. A session finishes when the client shuts down, after which the session cookie is removed.

Warning: Many web browsers have a session restore feature that will save all tabs and restore them the next time the browser is used. Session cookies will also be restored, as if the browser was never closed.

When an Expires date is set, the deadline is relative to the client the cookie is being set on, not the server.

最大年龄

Indicates the number of seconds until the cookie expires. A zero or negative number will expire the cookie immediately. If both Expires and Max-Age are set, Max-Age has precedence.