introduce mapper package

The mapper package contains functions related to creating and marshalling
reponses to machines.

Signed-off-by: Kristoffer Dalby <kristoffer@tailscale.com>

hscontrol/mapper/mapper_test.go

@@ -0,0 +1,131 @@
+package mapper
+
+import (
+	"fmt"
+	"testing"
+
+	"github.com/google/go-cmp/cmp"
+	"github.com/google/go-cmp/cmp/cmpopts"
+	"github.com/juanfont/headscale/hscontrol/types"
+	"gopkg.in/check.v1"
+	"tailscale.com/tailcfg"
+	"tailscale.com/types/dnstype"
+)
+
+func (s *Suite) TestGetMapResponseUserProfiles(c *check.C) {
+	mach := func(hostname, username string, userid uint) types.Machine {
+		return types.Machine{
+			Hostname: hostname,
+			UserID:   userid,
+			User: types.User{
+				Name: username,
+			},
+		}
+	}
+
+	machineInShared1 := mach("test_get_shared_nodes_1", "user1", 1)
+	machineInShared2 := mach("test_get_shared_nodes_2", "user2", 2)
+	machineInShared3 := mach("test_get_shared_nodes_3", "user3", 3)
+	machine2InShared1 := mach("test_get_shared_nodes_4", "user1", 1)
+
+	userProfiles := generateUserProfiles(
+		&machineInShared1,
+		types.Machines{
+			machineInShared2, machineInShared3, machine2InShared1,
+		},
+		"",
+	)
+
+	c.Assert(len(userProfiles), check.Equals, 3)
+
+	users := []string{
+		"user1", "user2", "user3",
+	}
+
+	for _, user := range users {
+		found := false
+		for _, userProfile := range userProfiles {
+			if userProfile.DisplayName == user {
+				found = true
+
+				break
+			}
+		}
+		c.Assert(found, check.Equals, true)
+	}
+}
+
+func TestDNSConfigMapResponse(t *testing.T) {
+	tests := []struct {
+		magicDNS bool
+		want     *tailcfg.DNSConfig
+	}{
+		{
+			magicDNS: true,
+			want: &tailcfg.DNSConfig{
+				Routes: map[string][]*dnstype.Resolver{
+					"shared1.foobar.headscale.net": {},
+					"shared2.foobar.headscale.net": {},
+					"shared3.foobar.headscale.net": {},
+				},
+				Domains: []string{
+					"foobar.headscale.net",
+					"shared1.foobar.headscale.net",
+				},
+				Proxied: true,
+			},
+		},
+		{
+			magicDNS: false,
+			want: &tailcfg.DNSConfig{
+				Domains: []string{"foobar.headscale.net"},
+				Proxied: false,
+			},
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(fmt.Sprintf("with-magicdns-%v", tt.magicDNS), func(t *testing.T) {
+			mach := func(hostname, username string, userid uint) types.Machine {
+				return types.Machine{
+					Hostname: hostname,
+					UserID:   userid,
+					User: types.User{
+						Name: username,
+					},
+				}
+			}
+
+			baseDomain := "foobar.headscale.net"
+
+			dnsConfigOrig := tailcfg.DNSConfig{
+				Routes:  make(map[string][]*dnstype.Resolver),
+				Domains: []string{baseDomain},
+				Proxied: tt.magicDNS,
+			}
+
+			machineInShared1 := mach("test_get_shared_nodes_1", "shared1", 1)
+			machineInShared2 := mach("test_get_shared_nodes_2", "shared2", 2)
+			machineInShared3 := mach("test_get_shared_nodes_3", "shared3", 3)
+			machine2InShared1 := mach("test_get_shared_nodes_4", "shared1", 1)
+
+			peersOfMachineInShared1 := types.Machines{
+				machineInShared1,
+				machineInShared2,
+				machineInShared3,
+				machine2InShared1,
+			}
+
+			got := generateDNSConfig(
+				&dnsConfigOrig,
+				baseDomain,
+				machineInShared1,
+				peersOfMachineInShared1,
+			)
+
+			if diff := cmp.Diff(tt.want, got, cmpopts.EquateEmpty()); diff != "" {
+				t.Errorf("expandAlias() = %v, want %v", got, tt.want)
+			}
+		})
+	}
+}