package gcp import ( "context" "errors" "testing" compute "cloud.google.com/go/compute/apiv1" "github.com/edgelesssys/constellation/coordinator/cloudprovider/cloudtypes" "github.com/edgelesssys/constellation/coordinator/core" "github.com/edgelesssys/constellation/coordinator/role" gax "github.com/googleapis/gax-go/v2" "github.com/stretchr/testify/assert" "github.com/stretchr/testify/require" "go.uber.org/goleak" "google.golang.org/api/iterator" computepb "google.golang.org/genproto/googleapis/cloud/compute/v1" "google.golang.org/protobuf/proto" ) func TestMain(m *testing.M) { goleak.VerifyTestMain(m, // https://github.com/census-instrumentation/opencensus-go/issues/1262 goleak.IgnoreTopFunction("go.opencensus.io/stats/view.(*worker).start"), ) } func TestRetrieveInstances(t *testing.T) { uid := "1234" someErr := errors.New("failed") newTestIter := func() *stubInstanceIterator { return &stubInstanceIterator{ instances: []*computepb.Instance{ { Name: proto.String("someInstance"), Metadata: &computepb.Metadata{ Items: []*computepb.Items{ { Key: proto.String("ssh-keys"), Value: proto.String("bob:ssh-rsa bobskey"), }, { Key: proto.String("key-2"), Value: proto.String("value-2"), }, { Key: proto.String(core.ConstellationUIDMetadataKey), Value: proto.String(uid), }, { Key: proto.String(core.RoleMetadataKey), Value: proto.String(role.Coordinator.String()), }, }, }, NetworkInterfaces: []*computepb.NetworkInterface{ { NetworkIP: proto.String("192.0.2.0"), AliasIpRanges: []*computepb.AliasIpRange{{IpCidrRange: proto.String("192.0.2.0/16")}}, AccessConfigs: []*computepb.AccessConfig{{NatIP: proto.String("192.0.2.1")}}, }, }, }, }, } } testCases := map[string]struct { client stubInstancesClient metadata stubMetadataClient instanceIter *stubInstanceIterator instanceIterMutator func(*stubInstanceIterator) wantInstances []cloudtypes.Instance wantErr bool }{ "retrieve works": { client: stubInstancesClient{}, metadata: stubMetadataClient{InstanceValue: uid}, instanceIter: newTestIter(), wantInstances: []cloudtypes.Instance{ { Name: "someInstance", ProviderID: "gce://someProject/someZone/someInstance", Role: role.Coordinator, AliasIPRanges: []string{"192.0.2.0/16"}, PublicIPs: []string{"192.0.2.1"}, PrivateIPs: []string{"192.0.2.0"}, SSHKeys: map[string][]string{"bob": {"ssh-rsa bobskey"}}, }, }, }, "instance name is null": { client: stubInstancesClient{}, metadata: stubMetadataClient{InstanceValue: uid}, instanceIter: newTestIter(), instanceIterMutator: func(sii *stubInstanceIterator) { sii.instances[0].Name = nil }, wantErr: true, }, "no instance with network ip": { client: stubInstancesClient{}, metadata: stubMetadataClient{InstanceValue: uid}, instanceIter: newTestIter(), instanceIterMutator: func(sii *stubInstanceIterator) { sii.instances[0].NetworkInterfaces = nil }, wantInstances: []cloudtypes.Instance{ { Name: "someInstance", ProviderID: "gce://someProject/someZone/someInstance", Role: role.Coordinator, AliasIPRanges: []string{}, PublicIPs: []string{}, PrivateIPs: []string{}, SSHKeys: map[string][]string{"bob": {"ssh-rsa bobskey"}}, }, }, }, "network ip is nil": { client: stubInstancesClient{}, metadata: stubMetadataClient{InstanceValue: uid}, instanceIter: newTestIter(), instanceIterMutator: func(sii *stubInstanceIterator) { sii.instances[0].NetworkInterfaces[0].NetworkIP = nil }, wantInstances: []cloudtypes.Instance{ { Name: "someInstance", ProviderID: "gce://someProject/someZone/someInstance", Role: role.Coordinator, AliasIPRanges: []string{"192.0.2.0/16"}, PublicIPs: []string{"192.0.2.1"}, PrivateIPs: []string{}, SSHKeys: map[string][]string{"bob": {"ssh-rsa bobskey"}}, }, }, }, "constellation id is not set": { client: stubInstancesClient{}, metadata: stubMetadataClient{InstanceValue: uid}, instanceIter: newTestIter(), instanceIterMutator: func(sii *stubInstanceIterator) { sii.instances[0].Metadata.Items[2].Key = proto.String("") }, wantInstances: []cloudtypes.Instance{}, }, "constellation retrieval fails": { client: stubInstancesClient{}, metadata: stubMetadataClient{InstanceErr: someErr}, instanceIter: newTestIter(), wantErr: true, }, "role is not set": { client: stubInstancesClient{}, metadata: stubMetadataClient{InstanceValue: uid}, instanceIter: newTestIter(), instanceIterMutator: func(sii *stubInstanceIterator) { sii.instances[0].Metadata.Items[3].Key = proto.String("") }, wantInstances: []cloudtypes.Instance{ { Name: "someInstance", ProviderID: "gce://someProject/someZone/someInstance", Role: role.Unknown, AliasIPRanges: []string{"192.0.2.0/16"}, PublicIPs: []string{"192.0.2.1"}, PrivateIPs: []string{"192.0.2.0"}, SSHKeys: map[string][]string{"bob": {"ssh-rsa bobskey"}}, }, }, }, "instance iterator Next() errors": { client: stubInstancesClient{}, metadata: stubMetadataClient{InstanceValue: uid}, instanceIter: &stubInstanceIterator{nextErr: someErr}, wantErr: true, }, } for name, tc := range testCases { t.Run(name, func(t *testing.T) { assert := assert.New(t) require := require.New(t) if tc.instanceIterMutator != nil { tc.instanceIterMutator(tc.instanceIter) } tc.client.ListInstanceIterator = tc.instanceIter client := Client{ instanceAPI: tc.client, metadataAPI: tc.metadata, } instances, err := client.RetrieveInstances(context.Background(), "someProject", "someZone") if tc.wantErr { assert.Error(err) return } require.NoError(err) assert.Equal(tc.wantInstances, instances) }) } } func TestRetrieveInstance(t *testing.T) { newTestInstance := func() *computepb.Instance { return &computepb.Instance{ Name: proto.String("someInstance"), Metadata: &computepb.Metadata{ Items: []*computepb.Items{ { Key: proto.String("key-1"), Value: proto.String("value-1"), }, { Key: proto.String("key-2"), Value: proto.String("value-2"), }, }, }, NetworkInterfaces: []*computepb.NetworkInterface{ { NetworkIP: proto.String("192.0.2.0"), AliasIpRanges: []*computepb.AliasIpRange{{IpCidrRange: proto.String("192.0.2.0/16")}}, AccessConfigs: []*computepb.AccessConfig{{NatIP: proto.String("192.0.2.1")}}, }, }, } } testCases := map[string]struct { client stubInstancesClient clientInstance *computepb.Instance clientInstanceMutator func(*computepb.Instance) wantInstance cloudtypes.Instance wantErr bool }{ "retrieve works": { client: stubInstancesClient{}, clientInstance: newTestInstance(), wantInstance: cloudtypes.Instance{ Name: "someInstance", ProviderID: "gce://someProject/someZone/someInstance", AliasIPRanges: []string{"192.0.2.0/16"}, PublicIPs: []string{"192.0.2.1"}, PrivateIPs: []string{"192.0.2.0"}, SSHKeys: map[string][]string{}, }, }, "retrieve with SSH key works": { client: stubInstancesClient{}, clientInstance: newTestInstance(), clientInstanceMutator: func(i *computepb.Instance) { i.Metadata.Items[0].Key = proto.String("ssh-keys") i.Metadata.Items[0].Value = proto.String("bob:ssh-rsa bobskey") }, wantInstance: cloudtypes.Instance{ Name: "someInstance", ProviderID: "gce://someProject/someZone/someInstance", AliasIPRanges: []string{"192.0.2.0/16"}, PublicIPs: []string{"192.0.2.1"}, PrivateIPs: []string{"192.0.2.0"}, SSHKeys: map[string][]string{"bob": {"ssh-rsa bobskey"}}, }, }, "retrieve with Role works": { client: stubInstancesClient{}, clientInstance: newTestInstance(), clientInstanceMutator: func(i *computepb.Instance) { i.Metadata.Items[0].Key = proto.String(core.RoleMetadataKey) i.Metadata.Items[0].Value = proto.String(role.Coordinator.String()) }, wantInstance: cloudtypes.Instance{ Name: "someInstance", ProviderID: "gce://someProject/someZone/someInstance", AliasIPRanges: []string{"192.0.2.0/16"}, PublicIPs: []string{"192.0.2.1"}, Role: role.Coordinator, PrivateIPs: []string{"192.0.2.0"}, SSHKeys: map[string][]string{}, }, }, "retrieve fails": { client: stubInstancesClient{ GetErr: errors.New("retrieve error"), }, clientInstance: nil, wantErr: true, }, "metadata item is null": { client: stubInstancesClient{}, clientInstance: newTestInstance(), clientInstanceMutator: func(i *computepb.Instance) { i.Metadata.Items[0] = nil }, wantInstance: cloudtypes.Instance{ Name: "someInstance", ProviderID: "gce://someProject/someZone/someInstance", AliasIPRanges: []string{"192.0.2.0/16"}, PublicIPs: []string{"192.0.2.1"}, PrivateIPs: []string{"192.0.2.0"}, SSHKeys: map[string][]string{}, }, }, "metadata key is null": { client: stubInstancesClient{}, clientInstance: newTestInstance(), clientInstanceMutator: func(i *computepb.Instance) { i.Metadata.Items[0].Key = nil }, wantInstance: cloudtypes.Instance{ Name: "someInstance", ProviderID: "gce://someProject/someZone/someInstance", AliasIPRanges: []string{"192.0.2.0/16"}, PublicIPs: []string{"192.0.2.1"}, PrivateIPs: []string{"192.0.2.0"}, SSHKeys: map[string][]string{}, }, }, "metadata value is null": { client: stubInstancesClient{}, clientInstance: newTestInstance(), clientInstanceMutator: func(i *computepb.Instance) { i.Metadata.Items[0].Value = nil }, wantInstance: cloudtypes.Instance{ Name: "someInstance", ProviderID: "gce://someProject/someZone/someInstance", AliasIPRanges: []string{"192.0.2.0/16"}, PublicIPs: []string{"192.0.2.1"}, PrivateIPs: []string{"192.0.2.0"}, SSHKeys: map[string][]string{}, }, }, "instance without network ip": { client: stubInstancesClient{}, clientInstance: newTestInstance(), clientInstanceMutator: func(i *computepb.Instance) { i.NetworkInterfaces[0] = nil }, wantInstance: cloudtypes.Instance{ Name: "someInstance", ProviderID: "gce://someProject/someZone/someInstance", AliasIPRanges: []string{}, PublicIPs: []string{}, PrivateIPs: []string{}, SSHKeys: map[string][]string{}, }, }, "network ip is nil": { client: stubInstancesClient{}, clientInstance: newTestInstance(), clientInstanceMutator: func(i *computepb.Instance) { i.NetworkInterfaces[0].NetworkIP = nil }, wantInstance: cloudtypes.Instance{ Name: "someInstance", ProviderID: "gce://someProject/someZone/someInstance", AliasIPRanges: []string{"192.0.2.0/16"}, PublicIPs: []string{"192.0.2.1"}, PrivateIPs: []string{}, SSHKeys: map[string][]string{}, }, }, "network alias cidr is nil": { client: stubInstancesClient{}, clientInstance: newTestInstance(), clientInstanceMutator: func(i *computepb.Instance) { i.NetworkInterfaces[0].AliasIpRanges[0].IpCidrRange = nil }, wantInstance: cloudtypes.Instance{ Name: "someInstance", ProviderID: "gce://someProject/someZone/someInstance", AliasIPRanges: []string{}, PublicIPs: []string{"192.0.2.1"}, PrivateIPs: []string{"192.0.2.0"}, SSHKeys: map[string][]string{}, }, }, "network public ip is nil": { client: stubInstancesClient{}, clientInstance: newTestInstance(), clientInstanceMutator: func(i *computepb.Instance) { i.NetworkInterfaces[0].AccessConfigs[0].NatIP = nil }, wantInstance: cloudtypes.Instance{ Name: "someInstance", ProviderID: "gce://someProject/someZone/someInstance", AliasIPRanges: []string{"192.0.2.0/16"}, PublicIPs: []string{}, PrivateIPs: []string{"192.0.2.0"}, SSHKeys: map[string][]string{}, }, }, } for name, tc := range testCases { t.Run(name, func(t *testing.T) { assert := assert.New(t) require := require.New(t) if tc.clientInstanceMutator != nil { tc.clientInstanceMutator(tc.clientInstance) } tc.client.GetInstance = tc.clientInstance client := Client{instanceAPI: tc.client} instance, err := client.RetrieveInstance(context.Background(), "someProject", "someZone", "someInstance") if tc.wantErr { assert.Error(err) return } require.NoError(err) assert.Equal(tc.wantInstance, instance) }) } } func TestRetrieveProjectID(t *testing.T) { someErr := errors.New("failed") testCases := map[string]struct { client stubMetadataClient wantValue string wantErr bool }{ "retrieve works": { client: stubMetadataClient{ProjectIDValue: "someProjectID"}, wantValue: "someProjectID", }, "retrieve fails": { client: stubMetadataClient{ProjectIDErr: someErr}, wantErr: true, }, } for name, tc := range testCases { t.Run(name, func(t *testing.T) { assert := assert.New(t) require := require.New(t) client := Client{metadataAPI: tc.client} value, err := client.RetrieveProjectID() if tc.wantErr { assert.Error(err) return } require.NoError(err) assert.Equal(tc.wantValue, value) }) } } func TestRetrieveZone(t *testing.T) { someErr := errors.New("failed") testCases := map[string]struct { client stubMetadataClient wantValue string wantErr bool }{ "retrieve works": { client: stubMetadataClient{ZoneValue: "someZone"}, wantValue: "someZone", }, "retrieve fails": { client: stubMetadataClient{ZoneErr: someErr}, wantErr: true, }, } for name, tc := range testCases { t.Run(name, func(t *testing.T) { assert := assert.New(t) require := require.New(t) client := Client{metadataAPI: tc.client} value, err := client.RetrieveZone() if tc.wantErr { assert.Error(err) return } require.NoError(err) assert.Equal(tc.wantValue, value) }) } } func TestRetrieveInstanceName(t *testing.T) { someErr := errors.New("failed") testCases := map[string]struct { client stubMetadataClient wantValue string wantErr bool }{ "retrieve works": { client: stubMetadataClient{InstanceNameValue: "someInstanceName"}, wantValue: "someInstanceName", }, "retrieve fails": { client: stubMetadataClient{InstanceNameErr: someErr}, wantErr: true, }, } for name, tc := range testCases { t.Run(name, func(t *testing.T) { assert := assert.New(t) require := require.New(t) client := Client{metadataAPI: tc.client} value, err := client.RetrieveInstanceName() if tc.wantErr { assert.Error(err) return } require.NoError(err) assert.Equal(tc.wantValue, value) }) } } func TestRetrieveInstanceMetadata(t *testing.T) { someErr := errors.New("failed") attr := "someAttribute" testCases := map[string]struct { client stubMetadataClient attr string wantValue string wantErr bool }{ "retrieve works": { client: stubMetadataClient{ InstanceValue: "someValue", InstanceErr: nil, }, wantValue: "someValue", }, "retrieve fails": { client: stubMetadataClient{ InstanceValue: "", InstanceErr: someErr, }, wantErr: true, }, } for name, tc := range testCases { t.Run(name, func(t *testing.T) { assert := assert.New(t) require := require.New(t) client := Client{metadataAPI: tc.client} value, err := client.RetrieveInstanceMetadata(attr) if tc.wantErr { assert.Error(err) return } require.NoError(err) assert.Equal(tc.wantValue, value) }) } } func TestSetInstanceMetadata(t *testing.T) { someErr := errors.New("failed") testCases := map[string]struct { client stubInstancesClient wantErr bool }{ "set works": { client: stubInstancesClient{ GetInstance: &computepb.Instance{ Metadata: &computepb.Metadata{ Fingerprint: proto.String("someFingerprint"), Kind: proto.String("compute#metadata"), Items: []*computepb.Items{}, }, }, }, }, "retrieve fails": { client: stubInstancesClient{ GetErr: someErr, }, wantErr: true, }, "retrieve returns nil": { wantErr: true, }, "setting fails": { client: stubInstancesClient{ GetInstance: &computepb.Instance{ Metadata: &computepb.Metadata{ Fingerprint: proto.String("someFingerprint"), Kind: proto.String("compute#metadata"), Items: []*computepb.Items{}, }, }, SetMetadataErr: someErr, }, wantErr: true, }, } for name, tc := range testCases { t.Run(name, func(t *testing.T) { assert := assert.New(t) require := require.New(t) client := Client{instanceAPI: tc.client} err := client.SetInstanceMetadata(context.Background(), "project", "zone", "instanceName", "key", "value") if tc.wantErr { assert.Error(err) return } require.NoError(err) }) } } func TestUnsetInstanceMetadata(t *testing.T) { someErr := errors.New("failed") testCases := map[string]struct { client stubInstancesClient wantErr bool }{ "unset works": { client: stubInstancesClient{ GetInstance: &computepb.Instance{ Metadata: &computepb.Metadata{ Fingerprint: proto.String("someFingerprint"), Kind: proto.String("compute#metadata"), Items: []*computepb.Items{}, }, }, }, }, "unset with existing key works": { client: stubInstancesClient{ GetInstance: &computepb.Instance{ Metadata: &computepb.Metadata{ Fingerprint: proto.String("someFingerprint"), Kind: proto.String("compute#metadata"), Items: []*computepb.Items{ { Key: proto.String("key"), Value: proto.String("value"), }, }, }, }, }, }, "retrieve fails": { client: stubInstancesClient{GetErr: someErr}, wantErr: true, }, "retrieve returns nil": { wantErr: true, }, "setting fails": { client: stubInstancesClient{ GetInstance: &computepb.Instance{ Metadata: &computepb.Metadata{ Fingerprint: proto.String("someFingerprint"), Kind: proto.String("compute#metadata"), Items: []*computepb.Items{}, }, }, SetMetadataErr: someErr, }, wantErr: true, }, } for name, tc := range testCases { t.Run(name, func(t *testing.T) { assert := assert.New(t) require := require.New(t) client := Client{instanceAPI: tc.client} err := client.UnsetInstanceMetadata(context.Background(), "project", "zone", "instanceName", "key") if tc.wantErr { assert.Error(err) return } require.NoError(err) }) } } func TestRetrieveSubnetworkAliasCIDR(t *testing.T) { aliasCIDR := "192.0.2.1/24" someErr := errors.New("some error") testCases := map[string]struct { stubInstancesClient stubInstancesClient stubSubnetworksClient stubSubnetworksClient wantAliasCIDR string wantErr bool }{ "RetrieveSubnetworkAliasCIDR works": { stubInstancesClient: stubInstancesClient{ GetInstance: &computepb.Instance{ NetworkInterfaces: []*computepb.NetworkInterface{ { Subnetwork: proto.String("projects/project/regions/region/subnetworks/subnetwork"), }, }, }, }, stubSubnetworksClient: stubSubnetworksClient{ GetSubnetwork: &computepb.Subnetwork{ IpCidrRange: &aliasCIDR, }, }, wantAliasCIDR: aliasCIDR, }, "instance has no network interface": { stubInstancesClient: stubInstancesClient{ GetInstance: &computepb.Instance{ NetworkInterfaces: []*computepb.NetworkInterface{}, }, }, wantErr: true, }, "cannot get instance": { stubInstancesClient: stubInstancesClient{ GetErr: someErr, }, wantErr: true, }, "cannot get subnetwork": { stubInstancesClient: stubInstancesClient{ GetInstance: &computepb.Instance{ NetworkInterfaces: []*computepb.NetworkInterface{ { Subnetwork: proto.String("projects/project/regions/region/subnetworks/subnetwork"), }, }, }, }, stubSubnetworksClient: stubSubnetworksClient{ GetErr: someErr, }, wantErr: true, }, "subnetwork has no cidr range": { stubInstancesClient: stubInstancesClient{ GetInstance: &computepb.Instance{ NetworkInterfaces: []*computepb.NetworkInterface{ { Subnetwork: proto.String("projects/project/regions/region/subnetworks/subnetwork"), }, }, }, }, stubSubnetworksClient: stubSubnetworksClient{ GetSubnetwork: &computepb.Subnetwork{}, }, wantErr: true, }, } for name, tc := range testCases { t.Run(name, func(t *testing.T) { assert := assert.New(t) require := require.New(t) client := Client{instanceAPI: tc.stubInstancesClient, subnetworkAPI: tc.stubSubnetworksClient} aliasCIDR, err := client.RetrieveSubnetworkAliasCIDR(context.Background(), "project", "zone", "subnetwork") if tc.wantErr { assert.Error(err) return } require.NoError(err) assert.Equal(tc.wantAliasCIDR, aliasCIDR) }) } } func TestClose(t *testing.T) { someErr := errors.New("failed") assert := assert.New(t) client := Client{instanceAPI: stubInstancesClient{}, subnetworkAPI: stubSubnetworksClient{}} assert.NoError(client.Close()) client = Client{instanceAPI: stubInstancesClient{CloseErr: someErr}, subnetworkAPI: stubSubnetworksClient{}} assert.Error(client.Close()) client = Client{instanceAPI: stubInstancesClient{}, subnetworkAPI: stubSubnetworksClient{CloseErr: someErr}} assert.Error(client.Close()) } func TestFetchSSHKeys(t *testing.T) { testCases := map[string]struct { metadata map[string]string wantKeys map[string][]string }{ "fetch works": { metadata: map[string]string{"ssh-keys": "bob:ssh-rsa bobskey"}, wantKeys: map[string][]string{"bob": {"ssh-rsa bobskey"}}, }, "google ssh key metadata is ignored": { metadata: map[string]string{"ssh-keys": "bob:ssh-rsa bobskey google-ssh {\"userName\":\"bob\",\"expireOn\":\"2021-06-14T16:59:03+0000\"}"}, wantKeys: map[string][]string{"bob": {"ssh-rsa bobskey"}}, }, "ssh key format error is ignored": { metadata: map[string]string{"ssh-keys": "incorrect-format"}, wantKeys: map[string][]string{}, }, "ssh key format space error is ignored": { metadata: map[string]string{"ssh-keys": "user:incorrect-key-format"}, wantKeys: map[string][]string{}, }, "metadata field empty": { metadata: map[string]string{"ssh-keys": ""}, wantKeys: map[string][]string{}, }, "metadata field missing": { metadata: map[string]string{}, wantKeys: map[string][]string{}, }, "multiple keys": { metadata: map[string]string{"ssh-keys": "bob:ssh-rsa bobskey\nalice:ssh-rsa alicekey"}, wantKeys: map[string][]string{ "bob": {"ssh-rsa bobskey"}, "alice": {"ssh-rsa alicekey"}, }, }, } for name, tc := range testCases { t.Run(name, func(t *testing.T) { assert := assert.New(t) keys := extractSSHKeys(tc.metadata) assert.Equal(tc.wantKeys, keys) }) } } type stubInstanceIterator struct { instances []*computepb.Instance nextErr error internalCounter int } func (i *stubInstanceIterator) Next() (*computepb.Instance, error) { if i.nextErr != nil { return nil, i.nextErr } if i.internalCounter >= len(i.instances) { i.internalCounter = 0 return nil, iterator.Done } resp := i.instances[i.internalCounter] i.internalCounter++ return resp, nil } type stubInstancesClient struct { GetInstance *computepb.Instance GetErr error ListInstanceIterator InstanceIterator SetMetadataOperation *compute.Operation SetMetadataErr error CloseErr error } func (s stubInstancesClient) Get(ctx context.Context, req *computepb.GetInstanceRequest, opts ...gax.CallOption) (*computepb.Instance, error) { return s.GetInstance, s.GetErr } func (s stubInstancesClient) List(ctx context.Context, req *computepb.ListInstancesRequest, opts ...gax.CallOption) InstanceIterator { return s.ListInstanceIterator } func (s stubInstancesClient) SetMetadata(ctx context.Context, req *computepb.SetMetadataInstanceRequest, opts ...gax.CallOption) (*compute.Operation, error) { return s.SetMetadataOperation, s.SetMetadataErr } func (s stubInstancesClient) Close() error { return s.CloseErr } type stubSubnetworksClient struct { GetSubnetwork *computepb.Subnetwork GetErr error SubnetworkIterator SubnetworkIterator CloseErr error } func (s stubSubnetworksClient) Get(ctx context.Context, req *computepb.GetSubnetworkRequest, opts ...gax.CallOption) (*computepb.Subnetwork, error) { return s.GetSubnetwork, s.GetErr } func (s stubSubnetworksClient) List(ctx context.Context, req *computepb.ListSubnetworksRequest, opts ...gax.CallOption) SubnetworkIterator { return s.SubnetworkIterator } func (s stubSubnetworksClient) Close() error { return s.CloseErr } type stubMetadataClient struct { InstanceValue string InstanceErr error ProjectIDValue string ProjectIDErr error ZoneValue string ZoneErr error InstanceNameValue string InstanceNameErr error } func (s stubMetadataClient) InstanceAttributeValue(attr string) (string, error) { return s.InstanceValue, s.InstanceErr } func (s stubMetadataClient) ProjectID() (string, error) { return s.ProjectIDValue, s.ProjectIDErr } func (s stubMetadataClient) Zone() (string, error) { return s.ZoneValue, s.ZoneErr } func (s stubMetadataClient) InstanceName() (string, error) { return s.InstanceNameValue, s.InstanceNameErr }