package docker import ( "context" "crypto/tls" "io/ioutil" "sort" "strings" "testing" "time" "github.com/docker/docker/api/types" "github.com/docker/docker/api/types/swarm" "github.com/influxdata/telegraf/testutil" "github.com/stretchr/testify/require" ) type MockClient struct { InfoF func(ctx context.Context) (types.Info, error) ContainerListF func(ctx context.Context, options types.ContainerListOptions) ([]types.Container, error) ContainerStatsF func(ctx context.Context, containerID string, stream bool) (types.ContainerStats, error) ContainerInspectF func(ctx context.Context, containerID string) (types.ContainerJSON, error) ServiceListF func(ctx context.Context, options types.ServiceListOptions) ([]swarm.Service, error) TaskListF func(ctx context.Context, options types.TaskListOptions) ([]swarm.Task, error) NodeListF func(ctx context.Context, options types.NodeListOptions) ([]swarm.Node, error) } func (c *MockClient) Info(ctx context.Context) (types.Info, error) { return c.InfoF(ctx) } func (c *MockClient) ContainerList( ctx context.Context, options types.ContainerListOptions, ) ([]types.Container, error) { return c.ContainerListF(ctx, options) } func (c *MockClient) ContainerStats( ctx context.Context, containerID string, stream bool, ) (types.ContainerStats, error) { return c.ContainerStatsF(ctx, containerID, stream) } func (c *MockClient) ContainerInspect( ctx context.Context, containerID string, ) (types.ContainerJSON, error) { return c.ContainerInspectF(ctx, containerID) } func (c *MockClient) ServiceList( ctx context.Context, options types.ServiceListOptions, ) ([]swarm.Service, error) { return c.ServiceListF(ctx, options) } func (c *MockClient) TaskList( ctx context.Context, options types.TaskListOptions, ) ([]swarm.Task, error) { return c.TaskListF(ctx, options) } func (c *MockClient) NodeList( ctx context.Context, options types.NodeListOptions, ) ([]swarm.Node, error) { return c.NodeListF(ctx, options) } var baseClient = MockClient{ InfoF: func(context.Context) (types.Info, error) { return info, nil }, ContainerListF: func(context.Context, types.ContainerListOptions) ([]types.Container, error) { return containerList, nil }, ContainerStatsF: func(c context.Context, s string, b bool) (types.ContainerStats, error) { return containerStats(s), nil }, ContainerInspectF: func(context.Context, string) (types.ContainerJSON, error) { return containerInspect(), nil }, ServiceListF: func(context.Context, types.ServiceListOptions) ([]swarm.Service, error) { return ServiceList, nil }, TaskListF: func(context.Context, types.TaskListOptions) ([]swarm.Task, error) { return TaskList, nil }, NodeListF: func(context.Context, types.NodeListOptions) ([]swarm.Node, error) { return NodeList, nil }, } func newClient(host string, tlsConfig *tls.Config) (Client, error) { return &baseClient, nil } func TestDockerGatherContainerStats(t *testing.T) { var acc testutil.Accumulator stats := testStats() tags := map[string]string{ "container_name": "redis", "container_image": "redis/image", } parseContainerStats(stats, &acc, tags, "123456789", true, true, "linux") // test docker_container_net measurement netfields := map[string]interface{}{ "rx_dropped": uint64(1), "rx_bytes": uint64(2), "rx_errors": uint64(3), "tx_packets": uint64(4), "tx_dropped": uint64(1), "rx_packets": uint64(2), "tx_errors": uint64(3), "tx_bytes": uint64(4), "container_id": "123456789", } nettags := copyTags(tags) nettags["network"] = "eth0" acc.AssertContainsTaggedFields(t, "docker_container_net", netfields, nettags) netfields = map[string]interface{}{ "rx_dropped": uint64(6), "rx_bytes": uint64(8), "rx_errors": uint64(10), "tx_packets": uint64(12), "tx_dropped": uint64(6), "rx_packets": uint64(8), "tx_errors": uint64(10), "tx_bytes": uint64(12), "container_id": "123456789", } nettags = copyTags(tags) nettags["network"] = "total" acc.AssertContainsTaggedFields(t, "docker_container_net", netfields, nettags) // test docker_blkio measurement blkiotags := copyTags(tags) blkiotags["device"] = "6:0" blkiofields := map[string]interface{}{ "io_service_bytes_recursive_read": uint64(100), "io_serviced_recursive_write": uint64(101), "container_id": "123456789", } acc.AssertContainsTaggedFields(t, "docker_container_blkio", blkiofields, blkiotags) blkiotags = copyTags(tags) blkiotags["device"] = "total" blkiofields = map[string]interface{}{ "io_service_bytes_recursive_read": uint64(100), "io_serviced_recursive_write": uint64(302), "container_id": "123456789", } acc.AssertContainsTaggedFields(t, "docker_container_blkio", blkiofields, blkiotags) // test docker_container_mem measurement memfields := map[string]interface{}{ "active_anon": uint64(0), "active_file": uint64(1), "cache": uint64(0), "container_id": "123456789", "fail_count": uint64(1), "hierarchical_memory_limit": uint64(0), "inactive_anon": uint64(0), "inactive_file": uint64(3), "limit": uint64(2000), "mapped_file": uint64(0), "max_usage": uint64(1001), "pgfault": uint64(2), "pgmajfault": uint64(0), "pgpgin": uint64(0), "pgpgout": uint64(0), "rss_huge": uint64(0), "rss": uint64(0), "total_active_anon": uint64(0), "total_active_file": uint64(0), "total_cache": uint64(0), "total_inactive_anon": uint64(0), "total_inactive_file": uint64(0), "total_mapped_file": uint64(0), "total_pgfault": uint64(0), "total_pgmajfault": uint64(0), "total_pgpgin": uint64(4), "total_pgpgout": uint64(0), "total_rss_huge": uint64(444), "total_rss": uint64(44), "total_unevictable": uint64(0), "total_writeback": uint64(55), "unevictable": uint64(0), "usage_percent": float64(55.55), "usage": uint64(1111), "writeback": uint64(0), } acc.AssertContainsTaggedFields(t, "docker_container_mem", memfields, tags) // test docker_container_cpu measurement cputags := copyTags(tags) cputags["cpu"] = "cpu-total" cpufields := map[string]interface{}{ "usage_total": uint64(500), "usage_in_usermode": uint64(100), "usage_in_kernelmode": uint64(200), "usage_system": uint64(100), "throttling_periods": uint64(1), "throttling_throttled_periods": uint64(0), "throttling_throttled_time": uint64(0), "usage_percent": float64(400.0), "container_id": "123456789", } acc.AssertContainsTaggedFields(t, "docker_container_cpu", cpufields, cputags) cputags["cpu"] = "cpu0" cpu0fields := map[string]interface{}{ "usage_total": uint64(1), "container_id": "123456789", } acc.AssertContainsTaggedFields(t, "docker_container_cpu", cpu0fields, cputags) cputags["cpu"] = "cpu1" cpu1fields := map[string]interface{}{ "usage_total": uint64(1002), "container_id": "123456789", } acc.AssertContainsTaggedFields(t, "docker_container_cpu", cpu1fields, cputags) // Those tagged filed should not be present because of offline CPUs cputags["cpu"] = "cpu2" cpu2fields := map[string]interface{}{ "usage_total": uint64(0), "container_id": "123456789", } acc.AssertDoesNotContainsTaggedFields(t, "docker_container_cpu", cpu2fields, cputags) cputags["cpu"] = "cpu3" cpu3fields := map[string]interface{}{ "usage_total": uint64(0), "container_id": "123456789", } acc.AssertDoesNotContainsTaggedFields(t, "docker_container_cpu", cpu3fields, cputags) } func TestDocker_WindowsMemoryContainerStats(t *testing.T) { var acc testutil.Accumulator d := Docker{ newClient: func(string, *tls.Config) (Client, error) { return &MockClient{ InfoF: func(ctx context.Context) (types.Info, error) { return info, nil }, ContainerListF: func(ctx context.Context, options types.ContainerListOptions) ([]types.Container, error) { return containerList, nil }, ContainerStatsF: func(ctx context.Context, containerID string, stream bool) (types.ContainerStats, error) { return containerStatsWindows(), nil }, ContainerInspectF: func(ctx context.Context, containerID string) (types.ContainerJSON, error) { return containerInspect(), nil }, ServiceListF: func(context.Context, types.ServiceListOptions) ([]swarm.Service, error) { return ServiceList, nil }, TaskListF: func(context.Context, types.TaskListOptions) ([]swarm.Task, error) { return TaskList, nil }, NodeListF: func(context.Context, types.NodeListOptions) ([]swarm.Node, error) { return NodeList, nil }, }, nil }, } err := d.Gather(&acc) require.NoError(t, err) } func TestContainerLabels(t *testing.T) { var tests = []struct { name string container types.Container include []string exclude []string expected map[string]string }{ { name: "Nil filters matches all", container: genContainerLabeled(map[string]string{ "a": "x", }), include: nil, exclude: nil, expected: map[string]string{ "a": "x", }, }, { name: "Empty filters matches all", container: genContainerLabeled(map[string]string{ "a": "x", }), include: []string{}, exclude: []string{}, expected: map[string]string{ "a": "x", }, }, { name: "Must match include", container: genContainerLabeled(map[string]string{ "a": "x", "b": "y", }), include: []string{"a"}, exclude: []string{}, expected: map[string]string{ "a": "x", }, }, { name: "Must not match exclude", container: genContainerLabeled(map[string]string{ "a": "x", "b": "y", }), include: []string{}, exclude: []string{"b"}, expected: map[string]string{ "a": "x", }, }, { name: "Include Glob", container: genContainerLabeled(map[string]string{ "aa": "x", "ab": "y", "bb": "z", }), include: []string{"a*"}, exclude: []string{}, expected: map[string]string{ "aa": "x", "ab": "y", }, }, { name: "Exclude Glob", container: genContainerLabeled(map[string]string{ "aa": "x", "ab": "y", "bb": "z", }), include: []string{}, exclude: []string{"a*"}, expected: map[string]string{ "bb": "z", }, }, { name: "Excluded Includes", container: genContainerLabeled(map[string]string{ "aa": "x", "ab": "y", "bb": "z", }), include: []string{"a*"}, exclude: []string{"*b"}, expected: map[string]string{ "aa": "x", }, }, } for _, tt := range tests { t.Run(tt.name, func(t *testing.T) { var acc testutil.Accumulator newClientFunc := func(host string, tlsConfig *tls.Config) (Client, error) { client := baseClient client.ContainerListF = func(context.Context, types.ContainerListOptions) ([]types.Container, error) { return []types.Container{tt.container}, nil } return &client, nil } d := Docker{ newClient: newClientFunc, LabelInclude: tt.include, LabelExclude: tt.exclude, } err := d.Gather(&acc) require.NoError(t, err) // Grab tags from a container metric var actual map[string]string for _, metric := range acc.Metrics { if metric.Measurement == "docker_container_cpu" { actual = metric.Tags } } for k, v := range tt.expected { require.Equal(t, v, actual[k]) } }) } } func genContainerLabeled(labels map[string]string) types.Container { c := containerList[0] c.Labels = labels return c } func TestContainerNames(t *testing.T) { var tests = []struct { name string containers [][]string include []string exclude []string expected []string }{ { name: "Nil filters matches all", include: nil, exclude: nil, expected: []string{"etcd", "etcd2", "acme", "acme-test", "foo"}, }, { name: "Empty filters matches all", include: []string{}, exclude: []string{}, expected: []string{"etcd", "etcd2", "acme", "acme-test", "foo"}, }, { name: "Match all containers", include: []string{"*"}, exclude: []string{}, expected: []string{"etcd", "etcd2", "acme", "acme-test", "foo"}, }, { name: "Include prefix match", include: []string{"etc*"}, exclude: []string{}, expected: []string{"etcd", "etcd2"}, }, { name: "Exact match", include: []string{"etcd"}, exclude: []string{}, expected: []string{"etcd"}, }, { name: "Star matches zero length", include: []string{"etcd2*"}, exclude: []string{}, expected: []string{"etcd2"}, }, { name: "Exclude matches all", include: []string{}, exclude: []string{"etc*"}, expected: []string{"acme", "acme-test", "foo"}, }, { name: "Exclude single", include: []string{}, exclude: []string{"etcd"}, expected: []string{"etcd2", "acme", "acme-test", "foo"}, }, { name: "Exclude all", include: []string{"*"}, exclude: []string{"*"}, expected: []string{}, }, { name: "Exclude item matching include", include: []string{"acme*"}, exclude: []string{"*test*"}, expected: []string{"acme"}, }, { name: "Exclude item no wildcards", include: []string{"acme*"}, exclude: []string{"test"}, expected: []string{"acme", "acme-test"}, }, } for _, tt := range tests { t.Run(tt.name, func(t *testing.T) { var acc testutil.Accumulator newClientFunc := func(host string, tlsConfig *tls.Config) (Client, error) { client := baseClient client.ContainerListF = func(context.Context, types.ContainerListOptions) ([]types.Container, error) { return containerList, nil } client.ContainerStatsF = func(c context.Context, s string, b bool) (types.ContainerStats, error) { return containerStats(s), nil } return &client, nil } d := Docker{ newClient: newClientFunc, ContainerInclude: tt.include, ContainerExclude: tt.exclude, } err := d.Gather(&acc) require.NoError(t, err) // Set of expected names var expected = make(map[string]bool) for _, v := range tt.expected { expected[v] = true } // Set of actual names var actual = make(map[string]bool) for _, metric := range acc.Metrics { if name, ok := metric.Tags["container_name"]; ok { actual[name] = true } } require.Equal(t, expected, actual) }) } } func TestContainerStatus(t *testing.T) { type expectation struct { // tags Status string // fields ContainerID string OOMKilled bool Pid int ExitCode int StartedAt time.Time FinishedAt time.Time UptimeNs int64 } var tests = []struct { name string now func() time.Time inspect types.ContainerJSON expect expectation }{ { name: "finished_at is zero value", now: func() time.Time { return time.Date(2018, 6, 14, 5, 51, 53, 266176036, time.UTC) }, inspect: containerInspect(), expect: expectation{ ContainerID: "e2173b9478a6ae55e237d4d74f8bbb753f0817192b5081334dc78476296b7dfb", Status: "running", OOMKilled: false, Pid: 1234, ExitCode: 0, StartedAt: time.Date(2018, 6, 14, 5, 48, 53, 266176036, time.UTC), UptimeNs: int64(3 * time.Minute), }, }, { name: "finished_at is non-zero value", inspect: func() types.ContainerJSON { i := containerInspect() i.ContainerJSONBase.State.FinishedAt = "2018-06-14T05:53:53.266176036Z" return i }(), expect: expectation{ ContainerID: "e2173b9478a6ae55e237d4d74f8bbb753f0817192b5081334dc78476296b7dfb", Status: "running", OOMKilled: false, Pid: 1234, ExitCode: 0, StartedAt: time.Date(2018, 6, 14, 5, 48, 53, 266176036, time.UTC), FinishedAt: time.Date(2018, 6, 14, 5, 53, 53, 266176036, time.UTC), UptimeNs: int64(5 * time.Minute), }, }, { name: "started_at is zero value", inspect: func() types.ContainerJSON { i := containerInspect() i.ContainerJSONBase.State.StartedAt = "" i.ContainerJSONBase.State.FinishedAt = "2018-06-14T05:53:53.266176036Z" return i }(), expect: expectation{ ContainerID: "e2173b9478a6ae55e237d4d74f8bbb753f0817192b5081334dc78476296b7dfb", Status: "running", OOMKilled: false, Pid: 1234, ExitCode: 0, FinishedAt: time.Date(2018, 6, 14, 5, 53, 53, 266176036, time.UTC), }, }, } for _, tt := range tests { t.Run(tt.name, func(t *testing.T) { var ( acc testutil.Accumulator newClientFunc = func(string, *tls.Config) (Client, error) { client := baseClient client.ContainerListF = func(context.Context, types.ContainerListOptions) ([]types.Container, error) { return containerList[:1], nil } client.ContainerInspectF = func(c context.Context, s string) (types.ContainerJSON, error) { return tt.inspect, nil } return &client, nil } d = Docker{newClient: newClientFunc} ) // mock time if tt.now != nil { now = tt.now } defer func() { now = time.Now }() err := acc.GatherError(d.Gather) require.NoError(t, err) fields := map[string]interface{}{ "oomkilled": tt.expect.OOMKilled, "pid": tt.expect.Pid, "exitcode": tt.expect.ExitCode, "container_id": tt.expect.ContainerID, } if started := tt.expect.StartedAt; !started.IsZero() { fields["started_at"] = started.UnixNano() fields["uptime_ns"] = tt.expect.UptimeNs } if finished := tt.expect.FinishedAt; !finished.IsZero() { fields["finished_at"] = finished.UnixNano() } acc.AssertContainsTaggedFields(t, "docker_container_status", fields, map[string]string{ "container_name": "etcd", "container_image": "quay.io/coreos/etcd", "container_version": "v2.2.2", "engine_host": "absol", "label1": "test_value_1", "label2": "test_value_2", "server_version": "17.09.0-ce", "container_status": tt.expect.Status, }) }) } } func TestDockerGatherInfo(t *testing.T) { var acc testutil.Accumulator d := Docker{ newClient: newClient, TagEnvironment: []string{"ENVVAR1", "ENVVAR2", "ENVVAR3", "ENVVAR5", "ENVVAR6", "ENVVAR7", "ENVVAR8", "ENVVAR9"}, } err := acc.GatherError(d.Gather) require.NoError(t, err) acc.AssertContainsTaggedFields(t, "docker", map[string]interface{}{ "n_listener_events": int(0), "n_cpus": int(4), "n_used_file_descriptors": int(19), "n_containers": int(108), "n_containers_running": int(98), "n_containers_stopped": int(6), "n_containers_paused": int(3), "n_images": int(199), "n_goroutines": int(39), }, map[string]string{ "engine_host": "absol", "server_version": "17.09.0-ce", }, ) acc.AssertContainsTaggedFields(t, "docker", map[string]interface{}{ "memory_total": int64(3840757760), }, map[string]string{ "engine_host": "absol", "server_version": "17.09.0-ce", }, ) acc.AssertContainsTaggedFields(t, "docker", map[string]interface{}{ "pool_blocksize": int64(65540), }, map[string]string{ "engine_host": "absol", "server_version": "17.09.0-ce", "unit": "bytes", }, ) acc.AssertContainsTaggedFields(t, "docker_data", map[string]interface{}{ "used": int64(17300000000), "total": int64(107400000000), "available": int64(36530000000), }, map[string]string{ "engine_host": "absol", "server_version": "17.09.0-ce", "unit": "bytes", }, ) acc.AssertContainsTaggedFields(t, "docker_metadata", map[string]interface{}{ "used": int64(20970000), "total": int64(2146999999), "available": int64(2126999999), }, map[string]string{ "engine_host": "absol", "server_version": "17.09.0-ce", "unit": "bytes", }, ) acc.AssertContainsTaggedFields(t, "docker_devicemapper", map[string]interface{}{ "base_device_size_bytes": int64(10740000000), "pool_blocksize_bytes": int64(65540), "data_space_used_bytes": int64(17300000000), "data_space_total_bytes": int64(107400000000), "data_space_available_bytes": int64(36530000000), "metadata_space_used_bytes": int64(20970000), "metadata_space_total_bytes": int64(2146999999), "metadata_space_available_bytes": int64(2126999999), "thin_pool_minimum_free_space_bytes": int64(10740000000), }, map[string]string{ "engine_host": "absol", "server_version": "17.09.0-ce", "pool_name": "docker-8:1-1182287-pool", }, ) acc.AssertContainsTaggedFields(t, "docker_container_cpu", map[string]interface{}{ "usage_total": uint64(1231652), "container_id": "b7dfbb9478a6ae55e237d4d74f8bbb753f0817192b5081334dc78476296e2173", }, map[string]string{ "container_name": "etcd2", "container_image": "quay.io:4443/coreos/etcd", "cpu": "cpu3", "container_version": "v2.2.2", "engine_host": "absol", "ENVVAR1": "loremipsum", "ENVVAR2": "dolorsitamet", "ENVVAR3": "=ubuntu:10.04", "ENVVAR7": "ENVVAR8=ENVVAR9", "label1": "test_value_1", "label2": "test_value_2", "server_version": "17.09.0-ce", "container_status": "running", }, ) acc.AssertContainsTaggedFields(t, "docker_container_mem", map[string]interface{}{ "container_id": "b7dfbb9478a6ae55e237d4d74f8bbb753f0817192b5081334dc78476296e2173", "limit": uint64(18935443456), "max_usage": uint64(0), "usage": uint64(0), "usage_percent": float64(0), }, map[string]string{ "engine_host": "absol", "container_name": "etcd2", "container_image": "quay.io:4443/coreos/etcd", "container_version": "v2.2.2", "ENVVAR1": "loremipsum", "ENVVAR2": "dolorsitamet", "ENVVAR3": "=ubuntu:10.04", "ENVVAR7": "ENVVAR8=ENVVAR9", "label1": "test_value_1", "label2": "test_value_2", "server_version": "17.09.0-ce", "container_status": "running", }, ) } func TestDockerGatherSwarmInfo(t *testing.T) { var acc testutil.Accumulator d := Docker{ newClient: newClient, } err := acc.GatherError(d.Gather) require.NoError(t, err) d.gatherSwarmInfo(&acc) // test docker_container_net measurement acc.AssertContainsTaggedFields(t, "docker_swarm", map[string]interface{}{ "tasks_running": int(2), "tasks_desired": uint64(2), }, map[string]string{ "service_id": "qolkls9g5iasdiuihcyz9rnx2", "service_name": "test1", "service_mode": "replicated", }, ) acc.AssertContainsTaggedFields(t, "docker_swarm", map[string]interface{}{ "tasks_running": int(1), "tasks_desired": int(1), }, map[string]string{ "service_id": "qolkls9g5iasdiuihcyz9rn3", "service_name": "test2", "service_mode": "global", }, ) } func TestContainerStateFilter(t *testing.T) { var tests = []struct { name string include []string exclude []string expected map[string][]string }{ { name: "default", expected: map[string][]string{ "status": {"running"}, }, }, { name: "include running", include: []string{"running"}, expected: map[string][]string{ "status": {"running"}, }, }, { name: "include glob", include: []string{"r*"}, expected: map[string][]string{ "status": {"restarting", "running", "removing"}, }, }, { name: "include all", include: []string{"*"}, expected: map[string][]string{ "status": {"created", "restarting", "running", "removing", "paused", "exited", "dead"}, }, }, { name: "exclude all", exclude: []string{"*"}, expected: map[string][]string{ "status": {}, }, }, { name: "exclude all", include: []string{"*"}, exclude: []string{"exited"}, expected: map[string][]string{ "status": {"created", "restarting", "running", "removing", "paused", "dead"}, }, }, } for _, tt := range tests { t.Run(tt.name, func(t *testing.T) { var acc testutil.Accumulator newClientFunc := func(host string, tlsConfig *tls.Config) (Client, error) { client := baseClient client.ContainerListF = func(ctx context.Context, options types.ContainerListOptions) ([]types.Container, error) { for k, v := range tt.expected { actual := options.Filters.Get(k) sort.Strings(actual) sort.Strings(v) require.Equal(t, v, actual) } return nil, nil } return &client, nil } d := Docker{ newClient: newClientFunc, ContainerStateInclude: tt.include, ContainerStateExclude: tt.exclude, } err := d.Gather(&acc) require.NoError(t, err) }) } } func TestContainerName(t *testing.T) { tests := []struct { name string clientFunc func(host string, tlsConfig *tls.Config) (Client, error) expected string }{ { name: "container stats name is preferred", clientFunc: func(host string, tlsConfig *tls.Config) (Client, error) { client := baseClient client.ContainerListF = func(context.Context, types.ContainerListOptions) ([]types.Container, error) { var containers []types.Container containers = append(containers, types.Container{ Names: []string{"/logspout/foo"}, }) return containers, nil } client.ContainerStatsF = func(ctx context.Context, containerID string, stream bool) (types.ContainerStats, error) { return types.ContainerStats{ Body: ioutil.NopCloser(strings.NewReader(`{"name": "logspout"}`)), }, nil } return &client, nil }, expected: "logspout", }, { name: "container stats without name uses container list name", clientFunc: func(host string, tlsConfig *tls.Config) (Client, error) { client := baseClient client.ContainerListF = func(context.Context, types.ContainerListOptions) ([]types.Container, error) { var containers []types.Container containers = append(containers, types.Container{ Names: []string{"/logspout"}, }) return containers, nil } client.ContainerStatsF = func(ctx context.Context, containerID string, stream bool) (types.ContainerStats, error) { return types.ContainerStats{ Body: ioutil.NopCloser(strings.NewReader(`{}`)), }, nil } return &client, nil }, expected: "logspout", }, } for _, tt := range tests { t.Run(tt.name, func(t *testing.T) { d := Docker{ newClient: tt.clientFunc, } var acc testutil.Accumulator err := d.Gather(&acc) require.NoError(t, err) for _, metric := range acc.Metrics { // This tag is set on all container measurements if metric.Measurement == "docker_container_mem" { require.Equal(t, tt.expected, metric.Tags["container_name"]) } } }) } }