46 lines
886 B
Go
46 lines
886 B
Go
package internal
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import (
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"fmt"
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"time"
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"github.com/miekg/dns"
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)
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type Recursor struct {
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Upstreams []string
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Client *dns.Client
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}
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type Resolved struct {
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RoundtripTime time.Duration
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UpstreamUsed string
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Attempts int
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Message *dns.Msg
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}
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func (r Recursor) Resolve(request *dns.Msg) (Resolved, error) {
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var result Resolved
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errs := make([]error, len(r.Upstreams))
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var err error
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var upstreamsTried int
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for _, upstream := range r.Upstreams {
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result.Message, result.RoundtripTime, err = r.Client.Exchange(request, upstream)
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upstreamsTried++
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if err == nil {
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result.UpstreamUsed = upstream
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result.Message.RecursionAvailable = true
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break
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}
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errs = append(errs, err)
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}
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result.Attempts = upstreamsTried
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if result.Message == nil && len(errs) > 0 {
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return result, fmt.Errorf("errors occured resolving domain: %+v", errs)
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}
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return result, nil
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}
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