Add core modules (SSH args parser, cache, resolver, NetBox client) with tests

internal/resolver/chain_test.go

@@ -0,0 +1,155 @@
+package resolver
+
+import (
+	"context"
+	"errors"
+	"testing"
+
+	"git.zb-server.de/Sebi/ssh-netbox-wrapper/internal/config"
+	"git.zb-server.de/Sebi/ssh-netbox-wrapper/internal/netbox"
+)
+
+// stubStrategy is a test double for Strategy.
+type stubStrategy struct {
+	name string
+	ip   string
+	err  error
+}
+
+func (s *stubStrategy) Name() string { return s.name }
+func (s *stubStrategy) Resolve(_ context.Context, _ *netbox.HostEntry, _ *netbox.Client) (string, error) {
+	return s.ip, s.err
+}
+
+func TestChain_FirstStrategySucceeds(t *testing.T) {
+	c := &Chain{strategies: []Strategy{
+		&stubStrategy{name: "first", ip: "10.0.0.1"},
+		&stubStrategy{name: "second", ip: "10.0.0.2"},
+	}}
+	ip, err := c.Resolve(context.Background(), &netbox.HostEntry{Name: "host"}, nil)
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+	if ip != "10.0.0.1" {
+		t.Errorf("got %q, want first strategy's IP %q", ip, "10.0.0.1")
+	}
+}
+
+func TestChain_FallsBackToNextStrategy(t *testing.T) {
+	c := &Chain{strategies: []Strategy{
+		&stubStrategy{name: "first", err: ErrNoIP},
+		&stubStrategy{name: "second", ip: "10.0.0.2"},
+	}}
+	ip, err := c.Resolve(context.Background(), &netbox.HostEntry{Name: "host"}, nil)
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+	if ip != "10.0.0.2" {
+		t.Errorf("got %q, want second strategy's IP %q", ip, "10.0.0.2")
+	}
+}
+
+func TestChain_AllStrategiesFail(t *testing.T) {
+	c := &Chain{strategies: []Strategy{
+		&stubStrategy{name: "a", err: ErrNoIP},
+		&stubStrategy{name: "b", err: errors.New("api error")},
+	}}
+	_, err := c.Resolve(context.Background(), &netbox.HostEntry{Name: "host"}, nil)
+	if err == nil {
+		t.Error("expected error when all strategies fail")
+	}
+}
+
+func TestChain_EmptyStrategies(t *testing.T) {
+	c := &Chain{}
+	_, err := c.Resolve(context.Background(), &netbox.HostEntry{Name: "host"}, nil)
+	if err == nil {
+		t.Error("empty chain should return an error")
+	}
+}
+
+func TestNew_PrimaryIP(t *testing.T) {
+	cfg := config.ResolverConfig{Strategies: []string{"primary_ip"}}
+	c, err := New(cfg)
+	if err != nil {
+		t.Fatalf("New: %v", err)
+	}
+	if len(c.strategies) != 1 {
+		t.Errorf("got %d strategies, want 1", len(c.strategies))
+	}
+	if c.strategies[0].Name() != "primary_ip" {
+		t.Errorf("strategy name: got %q, want %q", c.strategies[0].Name(), "primary_ip")
+	}
+}
+
+func TestNew_ManagementSubnet(t *testing.T) {
+	cfg := config.ResolverConfig{
+		Strategies:        []string{"management_subnet"},
+		ManagementSubnets: []string{"10.0.0.0/8"},
+	}
+	c, err := New(cfg)
+	if err != nil {
+		t.Fatalf("New: %v", err)
+	}
+	if c.strategies[0].Name() != "management_subnet" {
+		t.Errorf("strategy name: got %q, want %q", c.strategies[0].Name(), "management_subnet")
+	}
+}
+
+func TestNew_ManagementSubnet_InvalidCIDR(t *testing.T) {
+	cfg := config.ResolverConfig{
+		Strategies:        []string{"management_subnet"},
+		ManagementSubnets: []string{"not-a-cidr"},
+	}
+	_, err := New(cfg)
+	if err == nil {
+		t.Error("invalid CIDR should return an error")
+	}
+}
+
+func TestNew_InterfaceName(t *testing.T) {
+	cfg := config.ResolverConfig{
+		Strategies:    []string{"interface_name"},
+		InterfaceName: "mgmt0",
+	}
+	c, err := New(cfg)
+	if err != nil {
+		t.Fatalf("New: %v", err)
+	}
+	if c.strategies[0].Name() != "interface_name" {
+		t.Errorf("strategy name: got %q", c.strategies[0].Name())
+	}
+}
+
+func TestNew_InterfaceName_MissingConfig(t *testing.T) {
+	cfg := config.ResolverConfig{
+		Strategies:    []string{"interface_name"},
+		InterfaceName: "", // not set
+	}
+	_, err := New(cfg)
+	if err == nil {
+		t.Error("interface_name without config should return an error")
+	}
+}
+
+func TestNew_UnknownStrategy(t *testing.T) {
+	cfg := config.ResolverConfig{Strategies: []string{"nonexistent"}}
+	_, err := New(cfg)
+	if err == nil {
+		t.Error("unknown strategy should return an error")
+	}
+}
+
+func TestNew_MultipleStrategies(t *testing.T) {
+	cfg := config.ResolverConfig{
+		Strategies:        []string{"management_subnet", "primary_ip"},
+		ManagementSubnets: []string{"10.0.0.0/8"},
+	}
+	c, err := New(cfg)
+	if err != nil {
+		t.Fatalf("New: %v", err)
+	}
+	if len(c.strategies) != 2 {
+		t.Errorf("got %d strategies, want 2", len(c.strategies))
+	}
+}