node-api/docker/tools.go
Adam Štrauch 9348504f9e
Final touches
* Possibility to pass token in query param
* More appropriate names for gathering and resource updating functions
* Shorter measuring delay
* Container status available immediatelly when needed
2020-07-26 00:34:16 +02:00

132 lines
2.9 KiB
Go

package docker
import (
"bytes"
"log"
"os"
"os/exec"
"path/filepath"
"strconv"
"strings"
"time"
"github.com/rosti-cz/node-api/apps"
)
// Return bytes, inodes occupied by a directory and/or error if there is any
func du(path string) (int, int, error) {
space, inodes := 0, 0
// Occupied space
var out bytes.Buffer
var errOut bytes.Buffer
command := exec.Command("/usr/bin/du", "-b", "-s", path)
command.Stdout = &out
command.Stderr = &errOut
err := command.Run()
if err != nil {
log.Println(errOut.String())
return space, inodes, err
}
fields := strings.Fields(strings.TrimSpace(out.String()))
out.Reset()
errOut.Reset()
if len(fields) == 2 {
space, err = strconv.Atoi(fields[0])
if err != nil {
return space, inodes, err
}
}
// Occupied inodes
command = exec.Command("/usr/bin/du", "--inodes", "-s", path)
command.Stdout = &out
command.Stderr = &errOut
err = command.Run()
if err != nil {
log.Println(errOut.String())
return space, inodes, err
}
fields = strings.Fields(strings.TrimSpace(out.String()))
out.Reset()
errOut.Reset()
if len(fields) == 2 {
inodes, err = strconv.Atoi(fields[0])
if err != nil {
return inodes, inodes, err
}
}
return space, inodes, nil
}
// Removes content of given directory
func removeDirectory(dir string) error {
d, err := os.Open(dir)
if err != nil {
return err
}
defer d.Close()
names, err := d.Readdirnames(-1)
if err != nil {
return err
}
for _, name := range names {
err = os.RemoveAll(filepath.Join(dir, name))
if err != nil {
return err
}
}
return nil
}
// CPUMemoryStats returns list of applications with updated CPU and memory usage effectively.
// Sample is number of seconds between two measurements of the CPU usage. More means more precise.
func CPUMemoryStats(applist *[]apps.App, sample int) (*[]apps.App, error) {
if sample <= 0 {
sample = 1
}
containers := []Container{}
for _, app := range *applist {
containers = append(containers, Container{App: &app})
}
startMap := make(map[string]int64)
endMap := make(map[string]int64)
start := time.Now().UnixNano()
for _, container := range containers {
cpu, _, err := container.GetRawResourceStats()
if err != nil {
return nil, err
}
startMap[container.App.Name] = cpu
}
time.Sleep(time.Duration(sample) * time.Second)
for idx, container := range containers {
cpu, memory, err := container.GetRawResourceStats()
if err != nil {
return nil, err
}
endMap[container.App.Name] = cpu
containers[idx].App.MemoryUsage = memory
}
end := time.Now().UnixNano()
difference := (float64(end) - float64(start)) / float64(1000000000)
updatedApps := []apps.App{}
for _, container := range containers {
app := *container.App
app.CPUUsage = (float64(endMap[app.Name]) - float64(startMap[app.Name])) / difference / 10000000.0
updatedApps = append(updatedApps, app)
}
return &updatedApps, nil
}