Add nvidia_smi input to monitor nvidia GPUs (#4026)

plugins/inputs/nvidia_smi/nvidia_smi_test.go

@@ -0,0 +1,35 @@
+package nvidia_smi
+
+import (
+	"testing"
+)
+
+func TestParseLineStandard(t *testing.T) {
+	line := "85, 8114, 553, 7561, P2, 61, GeForce GTX 1070 Ti, GPU-d1911b8a-f5c8-5e66-057c-486561269de8, Default, 100, 93, 1\n"
+	tags, fields, err := parseLine(line)
+	if err != nil {
+		t.Fail()
+	}
+	if tags["name"] != "GeForce GTX 1070 Ti" {
+		t.Fail()
+	}
+	if temp, ok := fields["temperature_gpu"].(int); ok && temp == 61 {
+		t.Fail()
+	}
+}
+
+func TestParseLineEmptyLine(t *testing.T) {
+	line := "\n"
+	_, _, err := parseLine(line)
+	if err == nil {
+		t.Fail()
+	}
+}
+
+func TestParseLineBad(t *testing.T) {
+	line := "the quick brown fox jumped over the lazy dog"
+	_, _, err := parseLine(line)
+	if err == nil {
+		t.Fail()
+	}
+}