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@BobBurns BobBurns/cwtest.go
Last active Jan 1, 2018

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What would you like to do?
Example of pushing disk and cpu metrics to AWS Cloudwatch
/* quick and dirty code to play around pushing
* aws metrics to cloudwatch
*/
package main
import (
"bufio"
"time"
"fmt"
"log"
"os"
"syscall"
"sync"
"strings"
"strconv"
"regexp"
"github.com/aws/aws-sdk-go/aws"
"github.com/aws/aws-sdk-go/aws/session"
"github.com/aws/aws-sdk-go/service/cloudwatch"
)
var svc *cloudwatch.CloudWatch
func main() {
/* new session */
sess, err := session.NewSession(&aws.Config{
Region: aws.String("us-west-2")},
)
if err != nil {
panic(err)
}
svc = cloudwatch.New(sess)
/* log output */
f, err := os.OpenFile("cwtest.log", os.O_RDWR | os.O_CREATE | os.O_APPEND, 0666)
if err != nil {
panic(err)
}
defer f.Close()
log.SetOutput(f)
/* check metrics on seperate threads */
var wg sync.WaitGroup
wg.Add(1)
go get_disk_loop(wg)
wg.Add(1)
go load_avg_loop(wg)
wg.Add(1)
go check_swap_loop(wg)
/* shouldn't reach until interupt */
wg.Wait()
}
func get_disk_loop(wg sync.WaitGroup) {
defer wg.Done()
/* new session */
dims := []*cloudwatch.Dimension{}
dim1 := &cloudwatch.Dimension{
Name: aws.String("InstanceId"),
Value: aws.String("i-009614d62f6578510"),
}
dims = append(dims, dim1)
md := new(cloudwatch.MetricDatum)
md.SetDimensions(dims)
var status syscall.Statfs_t
var fperc float64
for {
/* check only "/" for now */
err := syscall.Statfs("/", &status)
if err != nil {
panic(err)
}
bav := float64(status.Bavail * uint64(status.Bsize))
bfr := float64(status.Blocks * uint64(status.Frsize))
fperc = bav/bfr
md.SetMetricName("disk_free:/")
md.SetTimestamp(time.Now())
md.SetUnit("Percent")
md.SetValue(fperc * 100)
err = md.Validate()
if err != nil {
panic(err)
}
/*publish disk free */
pmdin := &cloudwatch.PutMetricDataInput{
MetricData: []*cloudwatch.MetricDatum{md,},
Namespace: aws.String("CWBobby"),
}
log.Println(pmdin)
out, err := svc.PutMetricData(pmdin)
if err != nil {
panic(err)
}
log.Println("response: ", out)
md.SetMetricName("disk_avail:/")
md.SetTimestamp(time.Now())
md.SetUnit("Bytes")
md.SetValue(bav)
err = md.Validate()
if err != nil {
panic(err)
}
/*publish disk availible bytes */
pmdin = &cloudwatch.PutMetricDataInput{
MetricData: []*cloudwatch.MetricDatum{md,},
Namespace: aws.String("CWBobby"),
}
log.Println(pmdin)
out, err = svc.PutMetricData(pmdin)
if err != nil {
panic(err)
}
log.Println("response: ", out)
/* sleep and loop */
time.Sleep(time.Duration(3 * time.Minute))
}
}
/* could use some improvements */
func load_avg_loop(wg sync.WaitGroup) {
defer wg.Done()
dims := []*cloudwatch.Dimension{}
dim1 := &cloudwatch.Dimension{
Name: aws.String("InstanceId"),
Value: aws.String("i-009614d62f6578510"),
}
dims = append(dims, dim1)
md := new(cloudwatch.MetricDatum)
md.SetDimensions(dims)
var a [4]float64
var b [4]float64
var c [4]float64
var d [4]float64
var e [4]float64
var la1, la2, la3 float64
var cpun string
file, err := os.Open("/proc/stat")
if err != nil {
panic(err)
}
/* get first average */
fmt.Fscanf(file, "%s %f %f %f %f", &cpun, &a[0], &a[1], &a[2], &a[3])
file.Close()
log.Println(cpun)
log.Println(a[0], a[1], a[2], a[3])
/* loop 5 minute averages and publsh */
count := 0
for {
if count == 3 {
file, err = os.Open("/proc/stat")
if err != nil {
panic(err)
}
fmt.Fscanf(file, "%s %f %f %f %f", &cpun, &d[0], &d[1], &d[2], &d[3])
file.Close()
log.Println(d[0], d[1], d[2], d[3])
la3 = ((d[0]+d[1]+d[2]) - (a[0]+a[1]+a[2])) / ((d[0]+d[1]+d[2]+d[3]) - (a[0]+a[1]+a[2]+a[3]))
log.Printf("cpu load avg 15 min: %f\n", la3)
count = 0
a[0] = d[0]; a[1] = d[1]; a[2] = d[2]; a[3] = d[3]
continue
}
/* every 5 minutes count increases by 1 */
if count > 0 {
file, err = os.Open("/proc/stat")
if err != nil {
panic(err)
}
fmt.Fscanf(file, "%s %f %f %f %f", &cpun, &c[0], &c[1], &c[2], &c[3])
file.Close()
log.Println(c[0], c[1], c[2], c[3])
la2 = ((c[0]+c[1]+c[2]) - (a[0]+a[1]+a[2])) / ((c[0]+c[1]+c[2]+c[3]) - (a[0]+a[1]+a[2]+a[3]))
log.Printf("cpu load avg 5 min: %f\n", la1)
}
e[0] = a[0]; e[1] = a[1]; e[2] = a[2]; e[3] = a[3]
for i := 0; i < 5; i++ {
time.Sleep(time.Duration(1 * time.Minute))
file, err = os.Open("/proc/stat")
if err != nil {
panic(err)
}
fmt.Fscanf(file, "%s %f %f %f %f", &cpun, &b[0], &b[1], &b[2], &b[3])
file.Close()
log.Println(b[0], b[1], b[2], b[3])
la1 = ((b[0]+b[1]+b[2]) - (e[0]+e[1]+e[2])) / ((b[0]+b[1]+b[2]+b[3]) - (e[0]+e[1]+e[2]+e[3]))
log.Printf("cpu load avg 1 min: %f\n", la1)
/* push metric every 5 minutes */
if i == 3 {
write_cpu_metric(la1, la2, la3, md)
}
e[0] = b[0]; e[1] = b[1]; e[2] = b[2]; e[3] = b[3]
}
count++
}
}
func write_cpu_metric(la1, la2, la3 float64, md *cloudwatch.MetricDatum) {
md.SetMetricName("cpu_load1")
md.SetTimestamp(time.Now())
md.SetUnit("Percent")
md.SetValue(la1 * 100)
err := md.Validate()
if err != nil {
panic(err)
}
pmdin := &cloudwatch.PutMetricDataInput{
MetricData: []*cloudwatch.MetricDatum{md,},
Namespace: aws.String("CWBobby"),
}
log.Println(pmdin)
out, err := svc.PutMetricData(pmdin)
if err != nil {
panic(err)
}
log.Println("response: ", out)
md.SetMetricName("cpu_load5")
md.SetValue(la2 * 100)
err = md.Validate()
if err != nil {
panic(err)
}
pmdin = &cloudwatch.PutMetricDataInput{
MetricData: []*cloudwatch.MetricDatum{md,},
Namespace: aws.String("CWBobby"),
}
log.Println(pmdin)
out, err = svc.PutMetricData(pmdin)
if err != nil {
panic(err)
}
log.Println("response: ", out)
md.SetMetricName("cpu_load15")
md.SetValue(la3 * 100)
err = md.Validate()
if err != nil {
panic(err)
}
pmdin = &cloudwatch.PutMetricDataInput{
MetricData: []*cloudwatch.MetricDatum{md,},
Namespace: aws.String("CWBobby"),
}
log.Println(pmdin)
out, err = svc.PutMetricData(pmdin)
if err != nil {
panic(err)
}
log.Println("response: ", out)
}
/* you have to have swap configured on an ec2 micro instance
* to use this check
*/
func check_swap_loop(wg sync.WaitGroup) {
defer wg.Done()
dims := []*cloudwatch.Dimension{}
dim1 := &cloudwatch.Dimension{
Name: aws.String("InstanceId"),
Value: aws.String("i-009614d62f6578510"),
}
dims = append(dims, dim1)
md := new(cloudwatch.MetricDatum)
md.SetDimensions(dims)
var swapFree float64 = 0.0
var swapTotal float64 = 0.0
sfRe := regexp.MustCompile("SwapFree\\:")
stRe := regexp.MustCompile("SwapTotal\\:")
for {
file, err := os.Open("/proc/meminfo")
if err != nil {
panic(err)
}
scanner := bufio.NewScanner(file)
scanner.Split(bufio.ScanLines)
for scanner.Scan() {
t := scanner.Text()
if sfRe.MatchString(t) {
ts := strings.Fields(t)
sf, _ := strconv.Atoi(ts[1])
swapFree = float64(sf)
}
if stRe.MatchString(t) {
ts := strings.Fields(t)
st, _ := strconv.Atoi(ts[1])
swapTotal = float64(st)
}
}
file.Close()
md.SetMetricName("swap_free")
md.SetTimestamp(time.Now())
md.SetUnit("Bytes")
md.SetValue(swapFree)
err = md.Validate()
if err != nil {
panic(err)
}
/*publish swap free */
pmdin := &cloudwatch.PutMetricDataInput{
MetricData: []*cloudwatch.MetricDatum{md,},
Namespace: aws.String("CWBobby"),
}
log.Println(pmdin)
out, err := svc.PutMetricData(pmdin)
if err != nil {
panic(err)
}
log.Println("response: ", out)
md.SetMetricName("swap_total")
md.SetTimestamp(time.Now())
md.SetUnit("Bytes")
md.SetValue(swapTotal)
err = md.Validate()
if err != nil {
panic(err)
}
/*publish swap total */
pmdin = &cloudwatch.PutMetricDataInput{
MetricData: []*cloudwatch.MetricDatum{md,},
Namespace: aws.String("CWBobby"),
}
log.Println(pmdin)
out, err = svc.PutMetricData(pmdin)
if err != nil {
panic(err)
}
log.Println("response: ", out)
time.Sleep(time.Duration(3 * time.Minute))
}
}
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