// Proxy the request to the given endpoint, execute observers and middlewares chains
func (l *HttpLocation) proxyToEndpoint(tr *http.Transport, o *Options, endpoint endpoint.Endpoint, req request.Request) (*http.Response, error) {
a := &request.BaseAttempt{Endpoint: endpoint}
l.observerChain.ObserveRequest(req)
defer l.observerChain.ObserveResponse(req, a)
defer req.AddAttempt(a)
it := l.middlewareChain.GetIter()
defer l.unwindIter(it, req, a)
for v := it.Next(); v != nil; v = it.Next() {
a.Response, a.Error = v.ProcessRequest(req)
if a.Response != nil || a.Error != nil {
// Move the iterator forward to count it again once we unwind the chain
it.Next()
log.Errorf("Midleware intercepted request with response=%v, error=%v", a.Response, a.Error)
return a.Response, a.Error
}
}
// Forward the request and mirror the response
start := o.TimeProvider.UtcNow()
re, err := tr.RoundTrip(req.GetHttpRequest())
// Read the response as soon as we can, this will allow to release a connection to the pool
a.Response, a.Error = readResponse(&o.Limits, re, err)
a.Duration = o.TimeProvider.UtcNow().Sub(start)
return a.Response, a.Error
}
