4cfd19c7c9
* middleware/httproxy: implement debug queries Not too useful at the moment, but o-o.debug queries are supported and return the Comment from dns.google.com. Note that this is not always set. * improve documentation * Testing cleanups
45 lines
1.2 KiB
Go
45 lines
1.2 KiB
Go
// Package httpproxy is middleware that proxies requests to a HTTPs server doing DNS.
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package httpproxy
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import (
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"errors"
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"time"
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"github.com/miekg/coredns/middleware"
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"github.com/miekg/coredns/request"
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"github.com/miekg/dns"
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"golang.org/x/net/context"
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)
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var errUnreachable = errors.New("unreachable backend")
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// Proxy represents a middleware instance that can proxy requests to HTTPS servers.
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type Proxy struct {
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from string
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e Exchanger
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Next middleware.Handler
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}
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// ServeDNS satisfies the middleware.Handler interface.
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func (p *Proxy) ServeDNS(ctx context.Context, w dns.ResponseWriter, r *dns.Msg) (int, error) {
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start := time.Now()
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state := request.Request{W: w, Req: r}
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reply, backendErr := p.e.Exchange(state)
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if backendErr == nil && reply != nil {
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state.SizeAndDo(reply)
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w.WriteMsg(reply)
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RequestDuration.WithLabelValues(p.from).Observe(float64(time.Since(start) / time.Millisecond))
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return 0, nil
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}
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RequestDuration.WithLabelValues(p.from).Observe(float64(time.Since(start) / time.Millisecond))
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return dns.RcodeServerFailure, errUnreachable
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}
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// Name implements the Handler interface.
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func (p Proxy) Name() string { return "httpproxy" }
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