[Feature Request] HttpClient should retry request when server closes connection

[jas0ncn]

Background

When server closes connection at unfortunate time (keep-alive race), the http client will throw a ECONNRESET error.

Under this circumstance, agentkeepalive add req.reusedSocket to detect whether request is failed because reusing tcp connection.

Proposal

Add options retryWhenResuedSocketFail to HttpClient for whether retry request when get ECONNREST and req.reusedSocket is true. This options default value is true.

Seems Chrome do the same thing: https://codereview.chromium.org/303443011

[jas0ncn]

I can do something for this proposal if necessary.

[atian25]

urllib has 2 options: isRetry / retry, could we use it for this purpose