Implementation of Docker

apps/main.go

@@ -37,7 +37,7 @@ func List() (*[]App, error) {
 }
 
 // New creates new record about application in the database
-func New(name string, SSHPort int, HTTPPort int, image string, CPU string, memory int) error {
+func New(name string, SSHPort int, HTTPPort int, image string, CPU int, memory int) error {
 	app := App{
 		Name:     name,
 		SSHPort:  SSHPort,
@@ -49,6 +49,13 @@ func New(name string, SSHPort int, HTTPPort int, image string, CPU string, memor
 
 	db := common.GetDBConnection()
 
+	validationErrors := app.Validate()
+	if len(validationErrors) != 0 {
+		return ValidationError{
+			Errors: validationErrors,
+		}
+	}
+
 	if err := db.Create(app).Error; err != nil {
 		return err
 	}
@@ -57,7 +64,7 @@ func New(name string, SSHPort int, HTTPPort int, image string, CPU string, memor
 }
 
 // Update changes value about app in the database
-func Update(name string, SSHPort int, HTTPPort int, image string, CPU string, memory int) error {
+func Update(name string, SSHPort int, HTTPPort int, image string, CPU int, memory int) error {
 	var app App
 
 	db := common.GetDBConnection()
@@ -67,13 +74,20 @@ func Update(name string, SSHPort int, HTTPPort int, image string, CPU string, me
 		return err
 	}
 
-	err = db.Model(&app).Updates(App{
-		SSHPort:  SSHPort,
-		HTTPPort: HTTPPort,
-		Image:    image,
-		CPU:      CPU,
-		Memory:   memory,
-	}).Error
+	app.SSHPort = SSHPort
+	app.HTTPPort = HTTPPort
+	app.Image = image
+	app.CPU = CPU
+	app.Memory = memory
+
+	validationErrors := app.Validate()
+	if len(validationErrors) != 0 {
+		return ValidationError{
+			Errors: validationErrors,
+		}
+	}
+
+	err = db.Update(&app).Error
 
 	return err
 }

apps/types.go

@@ -1,6 +1,20 @@
 package apps
 
-import "github.com/jinzhu/gorm"
+import (
+	"regexp"
+	"strings"
+
+	"github.com/jinzhu/gorm"
+)
+
+// ValidationError is error that holds multiple validation error messages
+type ValidationError struct {
+	Errors []string
+}
+
+func (v ValidationError) Error() string {
+	return strings.Join(v.Errors, "\n")
+}
 
 // Label holds metadata about the application
 type Label struct {
@@ -15,12 +29,44 @@ type App struct {
 	SSHPort  int     `json:"ssh_port"`
 	HTTPPort int     `json:"http_port"`
 	Image    string  `json:"image"`
-	Status   string  `json:"status"` // running, data (no container, data only), stopped
-	CPU      string  `json:"cpu"`
+	CPU      int     `json:"cpu"`    // percentage, 200 means two CPU
 	Memory   int     `json:"memory"` // Limit in MB
 	Labels   []Label `json:"labels"` // username:cx or user_id:1
 
-	MemoryUsage int `json:"memory_usage"` // Usage in MB
-	DiskUsage   int `json:"disk_usage"`   // Usage in MB
+	Status      string `json:"status"`       // running, data-only (no container, data only), stopped
+	MemoryUsage int    `json:"memory_usage"` // Usage in MB
+	DiskUsage   int    `json:"disk_usage"`   // Usage in MB
 
 }
+
+// Validate do basic checks of the struct values
+func (a *App) Validate() []string {
+	var errors []string
+
+	nameRegExp := regexp.MustCompile(`^[a-z0-9_]{3,48}$`)
+	if !nameRegExp.MatchString(a.Name) {
+		errors = append(errors, "name can contain only characters, numbers and underscores and has to be between 3 and 48 characters")
+	}
+
+	if a.SSHPort < 0 && a.SSHPort > 65536 {
+		errors = append(errors, "SSH port has to be between 0 and 65536, where 0 means disabled")
+	}
+
+	if a.HTTPPort < 1 && a.HTTPPort > 65536 {
+		errors = append(errors, "HTTP port has to be between 1 and 65536")
+	}
+
+	if a.Image == "" {
+		errors = append(errors, "image cannot be empty")
+	}
+
+	if a.CPU < 10 && a.CPU > 800 {
+		errors = append(errors, "CPU value has be between 10 and 800")
+	}
+
+	if a.Memory < 32 && a.Memory > 16384 {
+		errors = append(errors, "Memory value has be between 32 and 16384")
+	}
+
+	return errors
+}

docker/docker.go

@@ -0,0 +1,222 @@
+package docker
+
+import (
+	"context"
+	"errors"
+	"log"
+	"strconv"
+	"strings"
+	"time"
+
+	"github.com/docker/docker/api/types"
+	"github.com/docker/docker/api/types/container"
+	"github.com/docker/docker/api/types/network"
+	dockerClient "github.com/docker/docker/client"
+	"github.com/docker/go-connections/nat"
+)
+
+// Docker timeout
+const dockerTimeout = 10
+
+// DOCKER_SOCK tells where to connect to docker, it will be always local sock
+const dockerSock = "unix:///var/run/docker.sock"
+
+// DOCKER_API_VERSION set API version of Docker, 1.40 belongs to Docker 19.03.11
+const dockerAPIVersion = "1.40"
+
+// Driver keeps everything for connection to Docker
+type Driver struct{}
+
+func (d *Driver) getClient() (*dockerClient.Client, error) {
+	cli, err := dockerClient.NewClient(dockerSock, dockerAPIVersion, nil, nil)
+	return cli, err
+}
+
+// ConnectionStatus checks connection to the Docker daemon
+func (d *Driver) ConnectionStatus() (bool, error) {
+	cli, err := d.getClient()
+	if err != nil {
+		return false, err
+	}
+
+	_, err = cli.ServerVersion(context.TODO())
+	if err != nil {
+		return false, err
+	}
+
+	return true, nil
+}
+
+func (d *Driver) nameToID(name string) (string, error) {
+	containerIDs, err := d.IsExist(name)
+	if err != nil {
+		return "", err
+	}
+
+	if len(containerIDs) == 0 {
+		return "", errors.New("no container found")
+	}
+	if len(containerIDs) > 1 {
+		return "", errors.New("multiple containers with the same name")
+	}
+
+	return containerIDs[0], nil
+}
+
+// Remove removes container represented by containerID
+func (d *Driver) Remove(name string) error {
+	log.Println("Removing container " + name)
+	cli, err := d.getClient()
+	if err != nil {
+		return err
+	}
+
+	containerID, err := d.nameToID(name)
+	if err != nil {
+		return err
+	}
+
+	timeout := time.Duration(dockerTimeout * time.Second)
+	err = cli.ContainerStop(context.TODO(), containerID, &timeout)
+	if err != nil {
+		return err
+	}
+
+	err = cli.ContainerRemove(context.TODO(), containerID, types.ContainerRemoveOptions{})
+
+	return err
+}
+
+// Start starts container represented by containerID
+func (d *Driver) Start(name string) error {
+	log.Println("Starting container " + name)
+	cli, err := d.getClient()
+	if err != nil {
+		return err
+	}
+
+	containerID, err := d.nameToID(name)
+	if err != nil {
+		return err
+	}
+
+	err = cli.ContainerStart(context.TODO(), containerID, types.ContainerStartOptions{})
+
+	return err
+}
+
+// Stop stops container represented by containerID
+func (d *Driver) Stop(name string) error {
+	log.Println("Stopping container " + name)
+	cli, err := d.getClient()
+	if err != nil {
+		return err
+	}
+
+	containerID, err := d.nameToID(name)
+	if err != nil {
+		return err
+	}
+
+	timeout := time.Duration(dockerTimeout * time.Second)
+	err = cli.ContainerStop(context.TODO(), containerID, &timeout)
+
+	return err
+}
+
+// IsExist checks existence of the container based on container name
+// Returns container IDs in case of existence. Otherwise
+// empty slice.
+func (d *Driver) IsExist(name string) ([]string, error) {
+	var containerIDs = make([]string, 0)
+
+	cli, err := d.getClient()
+	if err != nil {
+		return containerIDs, err
+	}
+
+	containers, err := cli.ContainerList(context.TODO(), types.ContainerListOptions{})
+	if err != nil {
+		return containerIDs, err
+	}
+
+	// We go through the containers and pick the ones which match the task name
+	for _, containerObject := range containers {
+		for _, name := range containerObject.Names {
+			name = strings.Trim(name, "/")
+			if strings.Split(name, ".")[0] == name {
+				containerIDs = append(containerIDs, containerObject.ID)
+			}
+		}
+	}
+
+	return containerIDs, nil
+}
+
+// Create creates the container
+// image - docker image
+// cmd - string slice of command and its arguments
+// volumePath - host's directory to mount into the container
+// returns container ID
+func (d *Driver) Create(name string, image string, volumePath string, HTTPPort int, SSHPort int, CPU int, memory int, cmd []string) (string, error) {
+	log.Println("Creating container " + name)
+	cli, err := d.getClient()
+	if err != nil {
+		return "", err
+	}
+
+	portmaps := make(nat.PortMap, 1)
+
+	portbindingsHTTP := make([]nat.PortBinding, 1)
+	portbindingsHTTP[0] = nat.PortBinding{
+		HostPort: strconv.Itoa(HTTPPort) + "/tcp",
+	}
+	portmaps["8000/tcp"] = portbindingsHTTP
+
+	if SSHPort != 0 {
+		portbindingsSSH := make([]nat.PortBinding, 1)
+		portbindingsSSH[0] = nat.PortBinding{
+			HostPort: strconv.Itoa(SSHPort) + "/tcp",
+		}
+		portmaps["22/tcp"] = portbindingsSSH
+	}
+
+	createdContainer, err := cli.ContainerCreate(
+		context.TODO(),
+		&container.Config{
+			Hostname: name,
+			Env:      []string{},
+			Image:    image,
+			Cmd:      cmd,
+		},
+		&container.HostConfig{
+			Resources: container.Resources{
+				CPUPeriod:         100,
+				CPUQuota:          int64(CPU),
+				Memory:            int64(memory*110/100)*1024 ^ 2, // Allow 10 % more memory so we have space for MemoryReservation
+				MemoryReservation: int64(memory)*1024 ^ 2,         // This should provide softer way how to limit the memory of our containers
+			},
+			PortBindings: portmaps,
+			AutoRemove:   false,
+			RestartPolicy: container.RestartPolicy{
+				Name:              "unless-stopped",
+				MaximumRetryCount: 3,
+			},
+			Binds: []string{
+				volumePath + ":/srv",
+			},
+		},
+		&network.NetworkingConfig{},
+		name,
+	)
+	if err != nil {
+		return "", err
+	}
+
+	containerID := createdContainer.ID
+
+	// I dunno if we want this
+	// err = cli.ContainerStart(context.TODO(), createdContainer.ID, types.ContainerStartOptions{})
+
+	return containerID, nil
+}

docker/du.go

@@ -0,0 +1,50 @@
+package docker
+
+import (
+	"bytes"
+	"os/exec"
+	"strconv"
+	"strings"
+)
+
+// 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
+	command := exec.Command("/usr/bin/du -m -s " + path)
+	command.Stdout = &out
+	err := command.Run()
+	if err != nil {
+		return space, inodes, err
+	}
+	fields := strings.Fields(strings.TrimSpace(out.String()))
+	out.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
+	err = command.Run()
+	if err != nil {
+		return space, inodes, err
+	}
+	fields = strings.Fields(strings.TrimSpace(out.String()))
+	out.Reset()
+
+	if len(fields) == 2 {
+		space, err = strconv.Atoi(fields[0])
+		if err != nil {
+			return inodes, inodes, err
+		}
+	}
+
+	return space, inodes, nil
+}

docker/main.go

@@ -0,0 +1 @@
+package docker

docker/types.go

@@ -0,0 +1,58 @@
+package docker
+
+import (
+	"path"
+
+	"github.com/rosti-cz/apps-api/apps"
+)
+
+// Container extends App struct from App
+type Container struct {
+	App apps.App
+}
+
+// volumeHostPath each container has one volume mounted into it,
+func (c *Container) volumeHostPath() string {
+	return path.Join("/srv", c.App.Name)
+}
+
+// Status returns state of the container
+// Possible values: running, stopped, data-only
+func (c *Container) Status() (string, error) {
+	return "", nil
+}
+
+// DiskSpace returns number of MB and inodes used by the container in it's mounted volume
+func (c *Container) DiskSpace() (int, int, error) {
+	return du(c.volumeHostPath())
+}
+
+// Create creates the container
+func (c *Container) Create() error {
+	return nil
+}
+
+// Start starts the container
+func (c *Container) Start() error {
+	return nil
+}
+
+// Stop stops the container
+func (c *Container) Stop() error {
+	return nil
+}
+
+// Reset restarts the container
+func (c *Container) Reset() error {
+	return nil
+}
+
+// Destroy removes the container but keeps the data so it can be created again
+func (c *Container) Destroy() error {
+	return nil
+}
+
+// Delete removes both data and the container
+func (c *Container) Delete() error {
+	return nil
+}

go.mod

@@ -7,4 +7,6 @@ require (
 	github.com/labstack/echo v3.3.10+incompatible
 	github.com/labstack/gommon v0.3.0 // indirect
 	golang.org/x/crypto v0.0.0-20200622213623-75b288015ac9 // indirect
+	github.com/docker/docker v1.13.1
+	github.com/docker/go-connections v0.4.0
 )

main.go

@@ -53,6 +53,9 @@ func main() {
 
 		err = apps.New(app.Name, app.SSHPort, app.HTTPPort, app.Image, app.CPU, app.Memory)
 		if err != nil {
+			if validationError, ok := err.(apps.ValidationError); ok {
+				return c.JSONPretty(http.StatusBadRequest, Message{Errors: validationError.Errors}, JSONIndent)
+			}
 			return c.JSONPretty(http.StatusInternalServerError, Message{Message: err.Error()}, JSONIndent)
 		}
 
@@ -71,6 +74,9 @@ func main() {
 
 		err = apps.Update(name, app.SSHPort, app.HTTPPort, app.Image, app.CPU, app.Memory)
 		if err != nil {
+			if validationError, ok := err.(apps.ValidationError); ok {
+				return c.JSONPretty(http.StatusBadRequest, Message{Errors: validationError.Errors}, JSONIndent)
+			}
 			return c.JSONPretty(http.StatusInternalServerError, Message{Message: err.Error()}, JSONIndent)
 		}
 

types.go

@@ -1,5 +1,7 @@
 package main
 
+// Message represents response with information about results of something
 type Message struct {
-	Message string `json:"message"`
+	Message string   `json:"message,omitempty"`
+	Errors  []string `json:"errors,omitempty"`
 }