golang1.18 Transport源码

以下是 Go 1.18 中 `http.Transport` 的源码注释：

// Transport is an implementation of RoundTripper that supports HTTP, HTTPS, and HTTP proxies
// (with or without proxy authentication). It implements the http.RoundTripper interface.
//
// By default, Transport caches connections for future re-use. This may leave many open
// connections when accessing many hosts. This behavior can be managed using Transport's
// CloseIdleConnections method and the MaxIdleConnsPerHost and DisableKeepAlives fields.
//
// Transports should be reused instead of created as needed. Transports are safe for
// concurrent use by multiple goroutines.
type Transport struct {
    // Proxy specifies a function to return a proxy for a given Request.
    // If the function returns a non-nil error, the request is aborted
    // with the provided error.
    //
    // If Proxy is nil or returns a nil *URL, no proxy is used.
    Proxy func(*Request) (*url.URL, error)

    // DialContext specifies the dial function for creating unencrypted TCP connections.
    // If DialContext is nil (and the deprecated Dial below is also nil),
    // then the transport dials using package net.
    DialContext func(ctx context.Context, network, addr string) (net.Conn, error)

    // ...
    // 其他字段和方法省略，具体可以参考 Go 的源码文档
    // ...
}

你可以通过访问 [Go 1.18 的源码仓库](https://github.com/golang/go/tree/go1.18/src/net/http) 查看完整的源代码实现。