0486dcfd07
- Extract DNSClient interface from resolver to allow dependency injection - Convert all resolver methods from package-level to receiver methods using the injectable DNS client - Rewrite resolver_test.go with a mock DNS client that simulates the full delegation chain (root → TLD → authoritative) in-process - Move 2 integration tests (real DNS) behind //go:build integration tag - Add NewFromLoggerWithClient constructor for test injection - Add LookupAllRecords implementation (was returning ErrNotImplemented) All unit tests are hermetic (no network) and complete in <1s. Total make check passes in ~5s. Closes #12
49 lines
968 B
Go
49 lines
968 B
Go
package resolver
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import (
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"context"
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"time"
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"github.com/miekg/dns"
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)
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// DNSClient abstracts DNS wire-protocol exchanges so the resolver
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// can be tested without hitting real nameservers.
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type DNSClient interface {
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ExchangeContext(
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ctx context.Context,
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msg *dns.Msg,
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addr string,
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) (*dns.Msg, time.Duration, error)
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}
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// udpClient wraps a real dns.Client for production use.
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type udpClient struct {
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timeout time.Duration
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}
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func (c *udpClient) ExchangeContext(
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ctx context.Context,
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msg *dns.Msg,
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addr string,
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) (*dns.Msg, time.Duration, error) {
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cl := &dns.Client{Timeout: c.timeout}
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return cl.ExchangeContext(ctx, msg, addr)
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}
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// tcpClient wraps a real dns.Client using TCP.
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type tcpClient struct {
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timeout time.Duration
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}
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func (c *tcpClient) ExchangeContext(
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ctx context.Context,
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msg *dns.Msg,
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addr string,
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) (*dns.Msg, time.Duration, error) {
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cl := &dns.Client{Net: "tcp", Timeout: c.timeout}
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return cl.ExchangeContext(ctx, msg, addr)
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}
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