Merge pull request #33 from Clivern/feature/latency

Feature/latency

README.md

@@ -5,7 +5,7 @@
     <p align="center">
         <a href="https://godoc.org/github.com/clivern/hippo"><img src="https://godoc.org/github.com/clivern/hippo?status.svg"></a>
         <a href="https://travis-ci.org/Clivern/Hippo"><img src="https://travis-ci.org/Clivern/Hippo.svg?branch=master"></a>
-        <a href="https://github.com/Clivern/Hippo/releases"><img src="https://img.shields.io/badge/Version-1.4.0-red.svg"></a>
+        <a href="https://github.com/Clivern/Hippo/releases"><img src="https://img.shields.io/badge/Version-1.5.0-red.svg"></a>
         <a href="https://goreportcard.com/report/github.com/Clivern/Hippo"><img src="https://goreportcard.com/badge/github.com/Clivern/Hippo?v=1.0.0"></a>
         <a href="https://github.com/Clivern/Hippo/blob/master/LICENSE"><img src="https://img.shields.io/badge/LICENSE-MIT-orange.svg"></a>
     </p>
@@ -281,6 +281,38 @@ exists := hippo.FileExists("/var/log/error.log")
 exists := hippo.DirExists("/var/log")
 ```
 
+**Latency Tracker Component**
+
+```golang
+httpClient := hippo.NewHTTPClient()
+
+latency := NewLatencyTracker()
+latency.NewAction("api.call")
+
+// First HTTP Call
+start := time.Now()
+httpClient.Get(
+    "https://httpbin.org/get",
+    map[string]string{},
+    map[string]string{},
+)
+latency.SetPoint("api.call", start, time.Now())
+
+// Another HTTP Call
+latency.SetStart("api.call", time.Now())
+httpClient.Get(
+    "https://httpbin.org/get",
+    map[string]string{},
+    map[string]string{},
+)
+latency.SetEnd("api.call", time.Now())
+
+// Now it will calculate the average
+fmt.Println(latency.GetLatency("api.call"))
+// Output 486.217112ms <nil>
+```
+
+
 ## Versioning
 
 For transparency into our release cycle and in striving to maintain backward compatibility, Hippo is maintained under the [Semantic Versioning guidelines](https://semver.org/) and release process is predictable and business-friendly.

latency.go

@@ -0,0 +1,94 @@
+// Copyright 2019 Clivern. All rights reserved.
+// Use of this source code is governed by the MIT
+// license that can be found in the LICENSE file.
+
+package hippo
+
+import (
+	"fmt"
+	"time"
+)
+
+// Point struct
+type Point struct {
+	Start time.Time
+	End   time.Time
+}
+
+// Latency struct
+type Latency struct {
+	Actions map[string][]Point
+}
+
+// NewLatencyTracker creates a new latency instance
+func NewLatencyTracker() *Latency {
+	return &Latency{}
+}
+
+// NewAction creates a new action tracking bucket
+func (l *Latency) NewAction(name string) {
+	l.Actions = make(map[string][]Point)
+	l.Actions[name] = []Point{}
+}
+
+// SetPoint adds a new point
+func (l *Latency) SetPoint(name string, start, end time.Time) {
+	if _, ok := l.Actions[name]; !ok {
+		l.NewAction(name)
+	}
+	l.Actions[name] = append(l.Actions[name], Point{Start: start, End: end})
+}
+
+// SetStart adds point start time
+func (l *Latency) SetStart(name string, start time.Time) bool {
+	if _, ok := l.Actions[name]; !ok {
+		l.NewAction(name)
+	}
+	l.Actions[name] = append(l.Actions[name], Point{Start: start})
+
+	return true
+}
+
+// SetEnd adds point end time
+func (l *Latency) SetEnd(name string, end time.Time) bool {
+	if _, ok := l.Actions[name]; !ok {
+		l.NewAction(name)
+	}
+
+	length := len(l.Actions[name])
+
+	if length <= 0 {
+		return false
+	}
+
+	if l.Actions[name][length-1].End.String() == "" {
+		return false
+	}
+
+	l.Actions[name][length-1].End = end
+
+	return true
+}
+
+// GetLatency returns average latency in nanoseconds for specific action
+func (l *Latency) GetLatency(name string) (time.Duration, error) {
+	var total time.Duration
+
+	for _, v := range l.Actions[name] {
+		total += v.GetLatency()
+	}
+
+	result := total.Nanoseconds() / int64(len(l.Actions[name]))
+	timeDuration, err := time.ParseDuration(fmt.Sprintf("%dns", result))
+
+	if err != nil {
+		return time.Duration(0), err
+	}
+
+	return timeDuration, nil
+}
+
+// GetLatency returns latency in nanoseconds
+func (p *Point) GetLatency() time.Duration {
+	return p.End.Sub(p.Start)
+}