Add nagios parser for exec input plugin

closes #762

plugins/parsers/nagios/parser_test.go

@@ -0,0 +1,89 @@
+package nagios
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+)
+
+const validOutput1 = `PING OK - Packet loss = 0%, RTA = 0.30 ms|rta=0.298000ms;4000.000000;6000.000000;0.000000 pl=0%;80;90;0;100
+This is a long output
+with three lines
+`
+const validOutput2 = "TCP OK - 0.008 second response time on port 80|time=0.008457s;;;0.000000;10.000000"
+const validOutput3 = "TCP OK - 0.008 second response time on port 80|time=0.008457"
+const invalidOutput3 = "PING OK - Packet loss = 0%, RTA = 0.30 ms"
+const invalidOutput4 = "PING OK - Packet loss = 0%, RTA = 0.30 ms| =3;;;; dgasdg =;;;; sff=;;;;"
+
+func TestParseValidOutput(t *testing.T) {
+	parser := NagiosParser{
+		MetricName: "nagios_test",
+	}
+
+	// Output1
+	metrics, err := parser.Parse([]byte(validOutput1))
+	require.NoError(t, err)
+	assert.Len(t, metrics, 2)
+	// rta
+	assert.Equal(t, "rta", metrics[0].Name())
+	assert.Equal(t, map[string]interface{}{
+		"value":    float64(0.298),
+		"warning":  float64(4000),
+		"critical": float64(6000),
+		"min":      float64(0),
+	}, metrics[0].Fields())
+	assert.Equal(t, map[string]string{"unit": "ms"}, metrics[0].Tags())
+	// pl
+	assert.Equal(t, "pl", metrics[1].Name())
+	assert.Equal(t, map[string]interface{}{
+		"value":    float64(0),
+		"warning":  float64(80),
+		"critical": float64(90),
+		"min":      float64(0),
+		"max":      float64(100),
+	}, metrics[1].Fields())
+	assert.Equal(t, map[string]string{"unit": "%"}, metrics[1].Tags())
+
+	// Output2
+	metrics, err = parser.Parse([]byte(validOutput2))
+	require.NoError(t, err)
+	assert.Len(t, metrics, 1)
+	// time
+	assert.Equal(t, "time", metrics[0].Name())
+	assert.Equal(t, map[string]interface{}{
+		"value": float64(0.008457),
+		"min":   float64(0),
+		"max":   float64(10),
+	}, metrics[0].Fields())
+	assert.Equal(t, map[string]string{"unit": "s"}, metrics[0].Tags())
+
+	// Output3
+	metrics, err = parser.Parse([]byte(validOutput3))
+	require.NoError(t, err)
+	assert.Len(t, metrics, 1)
+	// time
+	assert.Equal(t, "time", metrics[0].Name())
+	assert.Equal(t, map[string]interface{}{
+		"value": float64(0.008457),
+	}, metrics[0].Fields())
+	assert.Equal(t, map[string]string{}, metrics[0].Tags())
+
+}
+
+func TestParseInvalidOutput(t *testing.T) {
+	parser := NagiosParser{
+		MetricName: "nagios_test",
+	}
+
+	// invalidOutput3
+	metrics, err := parser.Parse([]byte(invalidOutput3))
+	require.NoError(t, err)
+	assert.Len(t, metrics, 0)
+
+	// invalidOutput4
+	metrics, err = parser.Parse([]byte(invalidOutput4))
+	require.NoError(t, err)
+	assert.Len(t, metrics, 0)
+
+}