From 4b3b41fea5f34994c36145fbc54a1d74df5e44f5 Mon Sep 17 00:00:00 2001
From: Regan Kuchan <regankuchan@gmail.com>
Date: Mon, 30 Nov 2015 16:29:55 -0800
Subject: [PATCH] Create trig plugin

closes #404
---
 plugins/all/all.go        |  1 +
 plugins/trig/trig.go      | 46 +++++++++++++++++++++++++++++++++++++++
 plugins/trig/trig_test.go | 33 ++++++++++++++++++++++++++++
 3 files changed, 80 insertions(+)
 create mode 100644 plugins/trig/trig.go
 create mode 100644 plugins/trig/trig_test.go

diff --git a/plugins/all/all.go b/plugins/all/all.go
index 37e7d27ea..ba0859f65 100644
--- a/plugins/all/all.go
+++ b/plugins/all/all.go
@@ -28,6 +28,7 @@ import (
 	_ "github.com/influxdb/telegraf/plugins/rethinkdb"
 	_ "github.com/influxdb/telegraf/plugins/statsd"
 	_ "github.com/influxdb/telegraf/plugins/system"
+	_ "github.com/influxdb/telegraf/plugins/trig"
 	_ "github.com/influxdb/telegraf/plugins/twemproxy"
 	_ "github.com/influxdb/telegraf/plugins/zfs"
 	_ "github.com/influxdb/telegraf/plugins/zookeeper"
diff --git a/plugins/trig/trig.go b/plugins/trig/trig.go
new file mode 100644
index 000000000..e966cbd46
--- /dev/null
+++ b/plugins/trig/trig.go
@@ -0,0 +1,46 @@
+package trig
+
+import (
+	"math"
+
+	"github.com/influxdb/telegraf/plugins"
+)
+
+type Trig struct {
+	x         float64
+	Amplitude float64
+}
+
+var TrigConfig = `
+  # Set the amplitude
+  amplitude = 10.0
+`
+
+func (s *Trig) SampleConfig() string {
+	return TrigConfig
+}
+
+func (s *Trig) Description() string {
+	return "Inserts sine and cosine waves for demonstration purposes"
+}
+
+func (s *Trig) Gather(acc plugins.Accumulator) error {
+	sinner := math.Sin((s.x*math.Pi)/5.0) * s.Amplitude
+	cosinner := math.Cos((s.x*math.Pi)/5.0) * s.Amplitude
+
+	fields := make(map[string]interface{})
+	fields["sine"] = sinner
+	fields["cosine"] = cosinner
+
+	tags := make(map[string]string)
+
+	s.x += 1.0
+	acc.AddFields("trig", fields, tags)
+
+	return nil
+}
+
+func init() {
+
+	plugins.Add("Trig", func() plugins.Plugin { return &Trig{x: 0.0} })
+}
diff --git a/plugins/trig/trig_test.go b/plugins/trig/trig_test.go
new file mode 100644
index 000000000..24218fe11
--- /dev/null
+++ b/plugins/trig/trig_test.go
@@ -0,0 +1,33 @@
+package trig
+
+import (
+	"math"
+	"testing"
+
+	"github.com/influxdb/telegraf/testutil"
+	"github.com/stretchr/testify/assert"
+	// "github.com/stretchr/testify/require"
+)
+
+func TestTrig(t *testing.T) {
+	s := &Trig{
+		Amplitude: 10.0,
+	}
+
+	for i := 0.0; i < 10.0; i++ {
+
+		var acc testutil.Accumulator
+
+		sine := math.Sin((i*math.Pi)/5.0) * s.Amplitude
+		cosine := math.Cos((i*math.Pi)/5.0) * s.Amplitude
+
+		s.Gather(&acc)
+
+		fields := make(map[string]interface{})
+		fields["sine"] = sine
+		fields["cosine"] = cosine
+
+		assert.True(t, acc.CheckFieldsValue("trig", fields))
+
+	}
+}