[Feature Request]: Change httpClientConfig.dialer to interface type for better extensibility

[farss]

Describe the feature / enhancement and how it would improve things

Current Behavior
In httpClientConfig struct, the dialer field is currently typed as concrete net.Dialer:

Proposed Change
Change the dialer field to use an interface type instead. This would allow for more flexibility in terms of what types of dialers can be used with the client.

Describe how your proposal will work, with code and/or pseudo-code

type Dialer interface {
    Dial(network, addr string) (net.Conn, error)
}

[bogdanfinn]

hey @farss, do you maybe have an example what type of dialer one could use here?

[farss]

The dialer interface would allow more flexibility in proxy operations. For example:

1. Selecting from multiple proxy pools
2. Implementing custom proxy rotation logic
3. Adding proxy health checks and failover

[bogdanfinn]

@farss thank you for the response. i have to think about it as we are sometimes using direct access to properties of the net.Dialer and the suggestion might introduce BC breaks.

especially here: https://github.com/bogdanfinn/tls-client/blob/master/connect.go#L125

[farss]

@bogdanfinn How about adding a proxy.ContextDialer to the httpClientConfig? If proxyDialer is set, then directly run proxyDialer.DialContext()?"

type httpClientConfig struct {
        ...
       proxyDialer proxy.ContextDialer
}


if config.proxyDialer != nil {
	dialer = config.proxyDialer
} else if config.proxyUrl != "" {
	......
}

I really need this right now. For example, currently when doing a socks proxy dial, it use default net.Dial timeout.

[bogdanfinn]

hey @farss not sure if i get your use case right, but changing the net.Dial timeout of the socks proxy dialer would just require some adjustments in the code here or am i wrong? :

https://github.com/bogdanfinn/tls-client/blob/master/connect.go#L152

This means we just need to pass the configured timeout down the handleSocks5ProxyDialer function here:
https://github.com/bogdanfinn/tls-client/blob/master/connect.go#L119

and use it like we use it on normal http proxies?

[bogdanfinn]

Ah nevermind. Its the proxy.Direct Dialer which is using the net.Dialer in there.

I got your point.
Let me try to work on a possible solution.

[farss]

@bogdanfinn Yes, and there's another scenario. I want to implement a feature where when doing a proxy dial, it simultaneously dials multiple socks5 proxies, and then uses the one that responds the fastest. This would require a custom proxy dial implementation. Haha

[bogdanfinn]

@farss here is a possible solution, what do you think of that?
https://github.com/bogdanfinn/tls-client/pull/164/files

The concrete usage would look like that:

options := []tls_client.HttpClientOption{
		
tls_client.WithProxyDialerFactory(func(proxyUrlStr string, timeout time.Duration, localAddr *net.TCPAddr, connectHeaders http.Header, logger tls_client.Logger) (proxy.ContextDialer, error) {
			myCustomDialer := proxy.Direct
			// do custom stuff here
			return myCustomDialer, nil
		}),
	}

	client, err := tls_client.NewHttpClient(tls_client.NewNoopLogger(), options...)
	if err != nil {
		log.Println(err)
		return
	}

[farss]

@bogdanfinn This is exactly what I wanted, It works for me, Thanks.

[bogdanfinn]

@farss merged it.