34 lines
764 B
Go
34 lines
764 B
Go
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package resolver
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import (
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"context"
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)
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// ChainResolver is a chain resolver. The primary resolver is used first and, if that
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// fails, we then attempt with the secondary resolver.
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type ChainResolver struct {
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Primary Resolver
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Secondary Resolver
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}
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// LookupHost implements Resolver.LookupHost
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func (c ChainResolver) LookupHost(ctx context.Context, hostname string) ([]string, error) {
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addrs, err := c.Primary.LookupHost(ctx, hostname)
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if err != nil {
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addrs, err = c.Secondary.LookupHost(ctx, hostname)
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}
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return addrs, err
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}
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// Network implements Resolver.Network
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func (c ChainResolver) Network() string {
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return "chain"
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}
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// Address implements Resolver.Address
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func (c ChainResolver) Address() string {
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return ""
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}
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var _ Resolver = ChainResolver{}
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