Implementing generic parser plugins and documentation

This constitutes a large change in how we will parse different data
formats going forward (for the plugins that support it)

This is working off @henrypfhu's changes.

plugins/parsers/influx/parser_test.go

@@ -0,0 +1,194 @@
+package influx
+
+import (
+	"testing"
+	"time"
+
+	"github.com/stretchr/testify/assert"
+)
+
+var exptime = time.Date(2009, time.November, 10, 23, 0, 0, 0, time.UTC)
+
+const (
+	validInflux        = "cpu_load_short,cpu=cpu0 value=10 1257894000000000000"
+	validInfluxNewline = "\ncpu_load_short,cpu=cpu0 value=10 1257894000000000000\n"
+	invalidInflux      = "I don't think this is line protocol"
+	invalidInflux2     = "{\"a\": 5, \"b\": {\"c\": 6}}"
+)
+
+const influxMulti = `
+cpu,host=foo,datacenter=us-east usage_idle=99,usage_busy=1
+cpu,host=foo,datacenter=us-east usage_idle=99,usage_busy=1
+cpu,host=foo,datacenter=us-east usage_idle=99,usage_busy=1
+cpu,host=foo,datacenter=us-east usage_idle=99,usage_busy=1
+cpu,host=foo,datacenter=us-east usage_idle=99,usage_busy=1
+cpu,host=foo,datacenter=us-east usage_idle=99,usage_busy=1
+cpu,host=foo,datacenter=us-east usage_idle=99,usage_busy=1
+`
+
+const influxMultiSomeInvalid = `
+cpu,host=foo,datacenter=us-east usage_idle=99,usage_busy=1
+cpu,host=foo,datacenter=us-east usage_idle=99,usage_busy=1
+cpu,host=foo,datacenter=us-east usage_idle=99,usage_busy=1
+cpu,cpu=cpu3, host=foo,datacenter=us-east usage_idle=99,usage_busy=1
+cpu,cpu=cpu4 , usage_idle=99,usage_busy=1
+cpu,host=foo,datacenter=us-east usage_idle=99,usage_busy=1
+`
+
+func TestParseValidInflux(t *testing.T) {
+	parser := InfluxParser{}
+
+	metrics, err := parser.Parse([]byte(validInflux))
+	assert.NoError(t, err)
+	assert.Len(t, metrics, 1)
+	assert.Equal(t, "cpu_load_short", metrics[0].Name())
+	assert.Equal(t, map[string]interface{}{
+		"value": float64(10),
+	}, metrics[0].Fields())
+	assert.Equal(t, map[string]string{
+		"cpu": "cpu0",
+	}, metrics[0].Tags())
+	assert.Equal(t, exptime, metrics[0].Time())
+
+	metrics, err = parser.Parse([]byte(validInfluxNewline))
+	assert.NoError(t, err)
+	assert.Len(t, metrics, 1)
+	assert.Equal(t, "cpu_load_short", metrics[0].Name())
+	assert.Equal(t, map[string]interface{}{
+		"value": float64(10),
+	}, metrics[0].Fields())
+	assert.Equal(t, map[string]string{
+		"cpu": "cpu0",
+	}, metrics[0].Tags())
+	assert.Equal(t, exptime, metrics[0].Time())
+}
+
+func TestParseLineValidInflux(t *testing.T) {
+	parser := InfluxParser{}
+
+	metric, err := parser.ParseLine(validInflux)
+	assert.NoError(t, err)
+	assert.Equal(t, "cpu_load_short", metric.Name())
+	assert.Equal(t, map[string]interface{}{
+		"value": float64(10),
+	}, metric.Fields())
+	assert.Equal(t, map[string]string{
+		"cpu": "cpu0",
+	}, metric.Tags())
+	assert.Equal(t, exptime, metric.Time())
+
+	metric, err = parser.ParseLine(validInfluxNewline)
+	assert.NoError(t, err)
+	assert.Equal(t, "cpu_load_short", metric.Name())
+	assert.Equal(t, map[string]interface{}{
+		"value": float64(10),
+	}, metric.Fields())
+	assert.Equal(t, map[string]string{
+		"cpu": "cpu0",
+	}, metric.Tags())
+	assert.Equal(t, exptime, metric.Time())
+}
+
+func TestParseMultipleValid(t *testing.T) {
+	parser := InfluxParser{}
+
+	metrics, err := parser.Parse([]byte(influxMulti))
+	assert.NoError(t, err)
+	assert.Len(t, metrics, 7)
+
+	for _, metric := range metrics {
+		assert.Equal(t, "cpu", metric.Name())
+		assert.Equal(t, map[string]string{
+			"datacenter": "us-east",
+			"host":       "foo",
+		}, metrics[0].Tags())
+		assert.Equal(t, map[string]interface{}{
+			"usage_idle": float64(99),
+			"usage_busy": float64(1),
+		}, metrics[0].Fields())
+	}
+}
+
+func TestParseSomeValid(t *testing.T) {
+	parser := InfluxParser{}
+
+	metrics, err := parser.Parse([]byte(influxMultiSomeInvalid))
+	assert.Error(t, err)
+	assert.Len(t, metrics, 4)
+
+	for _, metric := range metrics {
+		assert.Equal(t, "cpu", metric.Name())
+		assert.Equal(t, map[string]string{
+			"datacenter": "us-east",
+			"host":       "foo",
+		}, metrics[0].Tags())
+		assert.Equal(t, map[string]interface{}{
+			"usage_idle": float64(99),
+			"usage_busy": float64(1),
+		}, metrics[0].Fields())
+	}
+}
+
+// Test that default tags are applied.
+func TestParseDefaultTags(t *testing.T) {
+	parser := InfluxParser{
+		DefaultTags: map[string]string{
+			"tag": "default",
+		},
+	}
+
+	metrics, err := parser.Parse([]byte(influxMultiSomeInvalid))
+	assert.Error(t, err)
+	assert.Len(t, metrics, 4)
+
+	for _, metric := range metrics {
+		assert.Equal(t, "cpu", metric.Name())
+		assert.Equal(t, map[string]string{
+			"datacenter": "us-east",
+			"host":       "foo",
+			"tag":        "default",
+		}, metrics[0].Tags())
+		assert.Equal(t, map[string]interface{}{
+			"usage_idle": float64(99),
+			"usage_busy": float64(1),
+		}, metrics[0].Fields())
+	}
+}
+
+// Verify that metric tags will override default tags
+func TestParseDefaultTagsOverride(t *testing.T) {
+	parser := InfluxParser{
+		DefaultTags: map[string]string{
+			"host": "default",
+		},
+	}
+
+	metrics, err := parser.Parse([]byte(influxMultiSomeInvalid))
+	assert.Error(t, err)
+	assert.Len(t, metrics, 4)
+
+	for _, metric := range metrics {
+		assert.Equal(t, "cpu", metric.Name())
+		assert.Equal(t, map[string]string{
+			"datacenter": "us-east",
+			"host":       "foo",
+		}, metrics[0].Tags())
+		assert.Equal(t, map[string]interface{}{
+			"usage_idle": float64(99),
+			"usage_busy": float64(1),
+		}, metrics[0].Fields())
+	}
+}
+
+func TestParseInvalidInflux(t *testing.T) {
+	parser := InfluxParser{}
+
+	_, err := parser.Parse([]byte(invalidInflux))
+	assert.Error(t, err)
+	_, err = parser.Parse([]byte(invalidInflux2))
+	assert.Error(t, err)
+	_, err = parser.ParseLine(invalidInflux)
+	assert.Error(t, err)
+	_, err = parser.ParseLine(invalidInflux2)
+	assert.Error(t, err)
+}