/
docker_driver.go
425 lines (357 loc) · 11.9 KB
/
docker_driver.go
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/* Copyright 2020 PhysarumSM Development Team
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package docker_driver
import (
"bufio"
"encoding/json"
"errors"
"io"
"io/ioutil"
"math"
"strings"
"github.com/docker/docker/api/types"
"github.com/docker/docker/client"
"golang.org/x/net/context"
"github.com/docker/docker/api/types/container"
"github.com/docker/go-connections/nat"
)
type DockerConfig struct {
Name string
Image string
Port [2]string
Cmd []string
Memory int64 // in bytes min is 4M default is inf
Cpu float64 // between 0.00 to 1.00*cores
Network string
Env []string
}
// image should be imagename:version
// hash should be user/image@sha256:digest
// official images should be library/imagename
// TODO: Some of these functions read from the response body to get more information
// Considering using docker's own JSONMessage struct:
// https://godoc.org/github.com/docker/docker/pkg/jsonmessage#JSONMessage
// However, PushImage does rely on the Aux field, which does not have a defined json structure
// Builds an image given a build context and image name
// buildContext is a tar archive containing all files needed to build image, including Dockerfile
func BuildImage(buildContext io.Reader, image string) error {
ctx := context.Background()
cli, err := client.NewClientWithOpts(client.FromEnv, client.WithAPIVersionNegotiation())
if err != nil {
return err
}
defer cli.Close()
resp, err := cli.ImageBuild(ctx, buildContext, types.ImageBuildOptions{Tags: []string{image}})
if err != nil {
return err
}
defer resp.Body.Close()
// Possible that cli.ImageBuild() does not return an error, but we see an error from the response body
scanner := bufio.NewScanner(resp.Body)
for scanner.Scan() {
line := scanner.Text()
// fmt.Println(line)
var respObject struct {
// Most response lines have "stream" field instead of "error"
// But we only care about "error" field
Error string
}
err = json.Unmarshal([]byte(line), &respObject)
if err != nil {
return err
}
if respObject.Error != "" {
return errors.New(respObject.Error)
}
}
return nil
}
// Pull image and return image digest
func PullImage(image string) (digest string, err error) {
ctx := context.Background()
cli, err := client.NewClientWithOpts(client.FromEnv, client.WithAPIVersionNegotiation())
if err != nil {
return "", err
}
defer cli.Close()
resp, err := cli.ImagePull(ctx, image, types.ImagePullOptions{})
if err != nil {
return "", err
}
defer resp.Close()
// Extract image digest from response
// Possible that cli.ImageBuild() does not return an error, but we see an error from the response body
// Read until EOF sent to ensure proper transfer of image
scanner := bufio.NewScanner(resp)
for scanner.Scan() {
line := scanner.Text()
// fmt.Println(line)
var respObject struct {
Status string
Error string
}
err = json.Unmarshal([]byte(line), &respObject)
if err != nil {
return "", err
}
if respObject.Status != "" {
substrs := strings.Split(respObject.Status, " ")
if len(substrs) > 1 && substrs[0] == "Digest:" {
digest = substrs[1]
}
} else if respObject.Error != "" {
return "", errors.New(respObject.Error)
}
}
if digest == "" {
return "", errors.New("docker_driver: Error did not receive digest")
}
return digest, nil
}
// Push an image
// Returns its calculated digest (SHA256 hash of the image)
func PushImage(encodedAuth, image string) (digest string, err error) {
ctx := context.Background()
cli, err := client.NewClientWithOpts(client.FromEnv, client.WithAPIVersionNegotiation())
if err != nil {
return "", err
}
defer cli.Close()
resp, err := cli.ImagePush(ctx, image, types.ImagePushOptions{RegistryAuth:encodedAuth})
if err != nil {
return "", err
}
defer resp.Close()
// Extract image digest from repsonse body
// Possible that cli.ImageBuild() does not return an error, but we see an error from the response body
// Read until EOF sent to ensure proper transfer of image
scanner := bufio.NewScanner(resp)
for scanner.Scan() {
line := scanner.Text()
// fmt.Println(line)
var respObject struct {
// Only fields we care about are "error" or "digest"
Aux struct {
Digest string
}
Error string
}
err = json.Unmarshal([]byte(line), &respObject)
if err != nil {
return "", err
}
if respObject.Aux.Digest != "" {
digest = respObject.Aux.Digest
} else if respObject.Error != "" {
return "", errors.New(respObject.Error)
}
}
if digest == "" {
return "", errors.New("docker_driver: Error did not receive digest")
}
return digest, nil
}
// Save an image into a tar archive format
// Returns the tar archive in byte slice
func SaveImage(image string) ([]byte, error) {
ctx := context.Background()
cli, err := client.NewClientWithOpts(client.FromEnv, client.WithAPIVersionNegotiation())
if err != nil {
return nil, err
}
defer cli.Close()
resp, err := cli.ImageSave(ctx, []string{image})
if err != nil {
return nil, err
}
defer resp.Close()
savedImageTar, err := ioutil.ReadAll(resp)
if err != nil {
return nil, err
}
return savedImageTar, nil
}
func ListImages() ([]string, error) {
ctx := context.Background()
cli, err := client.NewClientWithOpts(client.FromEnv, client.WithAPIVersionNegotiation())
if err != nil {
return nil, err
}
defer cli.Close()
images, err := cli.ImageList(ctx, types.ImageListOptions{})
if err != nil {
return nil, err
}
var ilist []string
for _, image := range images {
ilist = append(ilist, image.ID[7:]) // skips the sha256 tag
}
return ilist, nil
}
func ListRunningContainers() ([]string, error) {
ctx := context.Background()
cli, err := client.NewClientWithOpts(client.FromEnv, client.WithAPIVersionNegotiation())
if err != nil {
return nil, err
}
defer cli.Close()
containers, err := cli.ContainerList(ctx, types.ContainerListOptions{})
if err != nil {
return nil, err
}
var clist []string
for _, container := range containers {
clist = append(clist, container.ID)
}
return clist, nil
}
// following official stats_helper calculations
func calculateContainerCPU(stats *types.Stats) (float64) {
cpuPercent := 0.0
cpuDelta := float64(stats.CPUStats.CPUUsage.TotalUsage) - float64(stats.PreCPUStats.CPUUsage.TotalUsage)
systemDelta := float64(stats.CPUStats.SystemUsage) - float64(stats.PreCPUStats.SystemUsage)
onlineCPUs := float64(stats.CPUStats.OnlineCPUs)
if onlineCPUs == 0.0 {
onlineCPUs = float64(len(stats.CPUStats.CPUUsage.PercpuUsage))
}
if systemDelta > 0.0 && cpuDelta > 0.0 {
cpuPercent = (cpuDelta / systemDelta) * onlineCPUs * 100.0
}
return cpuPercent
}
func calculateContainerMemory(stats *types.MemoryStats) (float64) {
memUsage := float64(stats.Usage) - float64(stats.Stats["cache"])
limit := float64(stats.Limit)
if limit != 0 {
return (memUsage / limit) * 100.0
}
return 0
}
// calculate container cpu and mem usage
func CheckContainerHealth(cont string) (float64, float64, error) {
ctx := context.Background()
cli, err := client.NewClientWithOpts(client.FromEnv, client.WithAPIVersionNegotiation())
if err != nil {
return 0, 0, err
}
defer cli.Close()
resp, err := cli.ContainerStats(ctx, cont, false)
if err != nil {
return 0, 0, err
}
var containerStats types.StatsJSON
decoder := json.NewDecoder(resp.Body)
decoder.Decode(&containerStats)
stats := containerStats.Stats
cpuPercent := calculateContainerCPU(&stats)
//fmt.Println("cpu", cpuPercent)
memPercent := calculateContainerMemory(&stats.MemoryStats)
//fmt.Println("mem", memPercent)
return cpuPercent, memPercent, nil
}
// stopping container
func StopContainer(cont string) (string, error) {
ctx := context.Background()
cli, err := client.NewClientWithOpts(client.FromEnv, client.WithAPIVersionNegotiation())
if err != nil {
return "", err
}
defer cli.Close()
if err := cli.ContainerStop(ctx, cont, nil); err != nil {
return "", err
}
return "success", nil
}
// deleting container
func DeleteContainer(cont string) (string, error) {
ctx := context.Background()
cli, err := client.NewClientWithOpts(client.FromEnv, client.WithAPIVersionNegotiation())
if err != nil {
return "", err
}
defer cli.Close()
if err := cli.ContainerRemove(ctx, cont, types.ContainerRemoveOptions{}); err != nil {
return "", err
}
return "success", nil
}
// restarting container
func RestartContainer(cont string) (string, error) {
ctx := context.Background()
cli, err := client.NewClientWithOpts(client.FromEnv, client.WithAPIVersionNegotiation())
if err != nil {
return "", err
}
defer cli.Close()
if err := cli.ContainerRestart(ctx, cont, nil); err != nil {
return "", err
}
return "success", nil
}
// resizing a container instance on the fly
func ResizeContainer(cont string, mem int64, cpu float64) (string, error) {
ctx := context.Background()
cli, err := client.NewClientWithOpts(client.FromEnv, client.WithAPIVersionNegotiation())
if err != nil {
return "", err
}
defer cli.Close()
_, err = cli.ContainerUpdate(ctx, cont, container.UpdateConfig{
Resources: container.Resources{
Memory: mem,
NanoCPUs: int64(cpu*(math.Pow(10, 9))),
},
});
if err != nil {
return "", err
}
return "success", nil
}
// create and run container - interactive and detached set
// image (already pulled) should be imagename:version
// default/empty cmd is /bin/bash
func RunContainer(opt DockerConfig) (string, error) {
ctx := context.Background()
cli, err := client.NewClientWithOpts(client.FromEnv, client.WithAPIVersionNegotiation())
if err != nil {
return "", err
}
defer cli.Close()
resp, err := cli.ContainerCreate(ctx, &container.Config{
Image: opt.Image,
Cmd: opt.Cmd,
ExposedPorts: nat.PortSet{ nat.Port(opt.Port[0]) : struct{}{} },
Tty: true,
Env: opt.Env,
},
&container.HostConfig{
NetworkMode: container.NetworkMode(opt.Network),
PortBindings: nat.PortMap{ nat.Port(opt.Port[0]) :
[]nat.PortBinding{ nat.PortBinding{ HostPort: opt.Port[1] } }, },
Resources: container.Resources{
Memory: opt.Memory,
NanoCPUs: int64(opt.Cpu*(math.Pow(10, 9))),
},
},
nil, opt.Name)
if err != nil {
return "", err
}
err = cli.ContainerStart(ctx, resp.ID, types.ContainerStartOptions{})
if err != nil {
return "", err
}
return resp.ID, nil
}