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
84 lines
1.9 KiB
Go
84 lines
1.9 KiB
Go
// Package resolver provides iterative DNS resolution from root nameservers.
|
|
// It traces the full delegation chain from IANA root servers through TLD
|
|
// and domain nameservers, never relying on upstream recursive resolvers.
|
|
package resolver
|
|
|
|
import (
|
|
"log/slog"
|
|
|
|
"go.uber.org/fx"
|
|
|
|
"sneak.berlin/go/dnswatcher/internal/logger"
|
|
)
|
|
|
|
// Query status constants matching the state model.
|
|
const (
|
|
StatusOK = "ok"
|
|
StatusError = "error"
|
|
StatusNXDomain = "nxdomain"
|
|
StatusNoData = "nodata"
|
|
)
|
|
|
|
// MaxCNAMEDepth is the maximum CNAME chain depth to follow.
|
|
const MaxCNAMEDepth = 10
|
|
|
|
// Params contains dependencies for Resolver.
|
|
type Params struct {
|
|
fx.In
|
|
|
|
Logger *logger.Logger
|
|
}
|
|
|
|
// NameserverResponse holds one nameserver's response for a query.
|
|
type NameserverResponse struct {
|
|
Nameserver string
|
|
Records map[string][]string
|
|
Status string
|
|
Error string
|
|
}
|
|
|
|
// Resolver performs iterative DNS resolution from root servers.
|
|
type Resolver struct {
|
|
log *slog.Logger
|
|
client DNSClient
|
|
tcp DNSClient
|
|
}
|
|
|
|
// New creates a new Resolver instance for use with uber/fx.
|
|
func New(
|
|
_ fx.Lifecycle,
|
|
params Params,
|
|
) (*Resolver, error) {
|
|
return &Resolver{
|
|
log: params.Logger.Get(),
|
|
client: &udpClient{timeout: queryTimeoutDuration},
|
|
tcp: &tcpClient{timeout: queryTimeoutDuration},
|
|
}, nil
|
|
}
|
|
|
|
// NewFromLogger creates a Resolver directly from an slog.Logger,
|
|
// useful for testing without the fx lifecycle.
|
|
func NewFromLogger(log *slog.Logger) *Resolver {
|
|
return &Resolver{
|
|
log: log,
|
|
client: &udpClient{timeout: queryTimeoutDuration},
|
|
tcp: &tcpClient{timeout: queryTimeoutDuration},
|
|
}
|
|
}
|
|
|
|
// NewFromLoggerWithClient creates a Resolver with a custom DNS
|
|
// client, useful for testing with mock DNS responses.
|
|
func NewFromLoggerWithClient(
|
|
log *slog.Logger,
|
|
client DNSClient,
|
|
) *Resolver {
|
|
return &Resolver{
|
|
log: log,
|
|
client: client,
|
|
tcp: client,
|
|
}
|
|
}
|
|
|
|
// Method implementations are in iterative.go.
|
|
|