Add support for using globs in devices list of diskio input plugin (#3687)

plugins/inputs/system/diskio_test.go

@@ -0,0 +1,121 @@
+package system
+
+import (
+	"testing"
+
+	"github.com/influxdata/telegraf/testutil"
+	"github.com/shirou/gopsutil/disk"
+	"github.com/stretchr/testify/require"
+)
+
+func TestDiskIO(t *testing.T) {
+	type Result struct {
+		stats map[string]disk.IOCountersStat
+		err   error
+	}
+	type Metric struct {
+		tags   map[string]string
+		fields map[string]interface{}
+	}
+
+	tests := []struct {
+		name    string
+		devices []string
+		result  Result
+		err     error
+		metrics []Metric
+	}{
+		{
+			name: "minimal",
+			result: Result{
+				stats: map[string]disk.IOCountersStat{
+					"sda": disk.IOCountersStat{
+						ReadCount:    888,
+						WriteCount:   5341,
+						ReadBytes:    100000,
+						WriteBytes:   200000,
+						ReadTime:     7123,
+						WriteTime:    9087,
+						Name:         "sda",
+						IoTime:       123552,
+						SerialNumber: "ab-123-ad",
+					},
+				},
+				err: nil,
+			},
+			err: nil,
+			metrics: []Metric{
+				Metric{
+					tags: map[string]string{
+						"name":   "sda",
+						"serial": "ab-123-ad",
+					},
+					fields: map[string]interface{}{
+						"reads":            uint64(888),
+						"writes":           uint64(5341),
+						"read_bytes":       uint64(100000),
+						"write_bytes":      uint64(200000),
+						"read_time":        uint64(7123),
+						"write_time":       uint64(9087),
+						"io_time":          uint64(123552),
+						"weighted_io_time": uint64(0),
+						"iops_in_progress": uint64(0),
+					},
+				},
+			},
+		},
+		{
+			name:    "glob device",
+			devices: []string{"sd*"},
+			result: Result{
+				stats: map[string]disk.IOCountersStat{
+					"sda": disk.IOCountersStat{
+						Name:      "sda",
+						ReadCount: 42,
+					},
+					"vda": disk.IOCountersStat{
+						Name:      "vda",
+						ReadCount: 42,
+					},
+				},
+				err: nil,
+			},
+			err: nil,
+			metrics: []Metric{
+				Metric{
+					tags: map[string]string{
+						"name":   "sda",
+						"serial": "unknown",
+					},
+					fields: map[string]interface{}{
+						"reads": uint64(42),
+					},
+				},
+			},
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			var mps MockPS
+			mps.On("DiskIO").Return(tt.result.stats, tt.result.err)
+
+			var acc testutil.Accumulator
+
+			diskio := &DiskIO{
+				ps:      &mps,
+				Devices: tt.devices,
+			}
+			err := diskio.Gather(&acc)
+			require.Equal(t, tt.err, err)
+
+			for _, metric := range tt.metrics {
+				for k, v := range metric.fields {
+					require.True(t, acc.HasPoint("diskio", metric.tags, k, v),
+						"missing point: diskio %v %q: %v", metric.tags, k, v)
+				}
+			}
+			require.Equal(t, len(tt.metrics), int(acc.NMetrics()), "unexpected number of metrics")
+			require.True(t, mps.AssertExpectations(t))
+		})
+	}
+}