Merge pull request #13 from FMotalleb/docker-connection

feat: Docker-connection

config.local.yaml

@@ -5,9 +5,15 @@
 jobs:
   - name: Test Job
     tasks:
-      - command: ip a -pt
-        retries: 5
+      - command: php -v
         retry-delay: 5s
+        connections:
+          - image: docker-mysql-database-phpmyadmin
+            volumes:
+              - "/home/motalleb/Downloads:/var/local/test"
+        env:
+          SHELL: /bin/bash
+
     schedulers:
       - on-init: true
       - interval: 10m10s

config/config.go

@@ -64,6 +64,11 @@ type (
 		OnFail []Task `mapstructure:"on-fail" json:"on_fail,omitempty"`
 	}
 	TaskConnection struct {
-		Local bool
+		Local            bool     `mapstructure:"local" json:"local,omitempty"`
+		DockerConnection string   `mapstructure:"docker" json:"docker,omitempty"`
+		ContainerName    string   `mapstructure:"container" json:"container,omitempty"`
+		ImageName        string   `mapstructure:"image" json:"image,omitempty"`
+		Volumes          []string `mapstructure:"volumes" json:"volumes,omitempty"`
+		Networks         []string `mapstructure:"networks" json:"networks,omitempty"`
 	}
 )

config/validators.go

@@ -74,7 +74,7 @@ func (t *Task) Validate(log *logrus.Entry) error {
 		)
 	}
 	if err := credential.Validate(log, t.UserName, t.GroupName); err != nil {
-		return err
+		log.WithError(err).Warn("Be careful when using credentials, in local mode you cant use credentials unless running as root")
 	}
 	if t.Command != "" && (t.Data != nil || t.Headers != nil) {
 		return fmt.Errorf("command cannot have data or headers field, violating command: `%s`", t.Command)

core/cmd_connection/compiler.go

@@ -1,18 +1,27 @@
+// Package connection
 package connection
 
 import (
-	"log"
-
 	"github.com/sirupsen/logrus"
 
 	"github.com/FMotalleb/crontab-go/abstraction"
 	"github.com/FMotalleb/crontab-go/config"
 )
 
+// CompileConnection compiles the task connection based on the provided configuration and logger.
+// It returns an abstraction.CmdConnection interface based on the type of connection specified in the configuration.
+// If the connection type is not recognized or invalid, it logs a fatal error and returns nil.
 func CompileConnection(conn *config.TaskConnection, logger *logrus.Entry) abstraction.CmdConnection {
-	if conn.Local {
+	logger.Warn(conn)
+	switch {
+	case conn.Local:
 		return NewLocalCMDConn(logger)
+	case conn.ContainerName != "" && conn.ImageName == "":
+		return NewDockerAttachConnection(logger, conn)
+	case conn.ImageName != "":
+		return NewDockerCreateConnection(logger, conn)
 	}
-	log.Fatalln("cannot compile given taskConnection", conn)
+
+	logger.WithField("taskConnection", conn).Error("cannot compile given taskConnection")
 	return nil
 }

core/cmd_connection/docker_attach.go

@@ -0,0 +1,125 @@
+package connection
+
+import (
+	"bytes"
+	"context"
+	"io"
+
+	"github.com/docker/docker/api/types"
+	"github.com/docker/docker/client"
+	"github.com/sirupsen/logrus"
+
+	"github.com/FMotalleb/crontab-go/abstraction"
+	"github.com/FMotalleb/crontab-go/config"
+)
+
+type DockerAttachConnection struct {
+	conn        *config.TaskConnection
+	log         *logrus.Entry
+	cli         *client.Client
+	execCFG     *types.ExecConfig
+	containerID string
+	ctx         context.Context
+}
+
+// NewDockerAttachConnection creates a new DockerAttachConnection instance.
+// It initializes the connection configuration and logging fields.
+// Parameters:
+// - log: A logrus.Entry instance for logging purposes.
+// - conn: A TaskConnection instance containing the connection configuration.
+// Returns:
+// - A new instance of DockerAttachConnection implementing the CmdConnection interface.
+func NewDockerAttachConnection(log *logrus.Entry, conn *config.TaskConnection) abstraction.CmdConnection {
+	return &DockerAttachConnection{
+		conn: conn,
+		log: log.WithFields(
+			logrus.Fields{
+				"connection":  "docker",
+				"docker-mode": "attach",
+			},
+		),
+	}
+}
+
+// Prepare sets up the DockerAttachConnection for executing a task.
+// It reshapes the environment variables, sets the context, and creates an exec configuration.
+// Parameters:
+// - ctx: A context.Context instance for managing the request lifetime.
+// - task: A Task instance containing the task configuration.
+// Returns:
+// - An error if the preparation fails, otherwise nil.
+func (d *DockerAttachConnection) Prepare(ctx context.Context, task *config.Task) error {
+	shell, shellArgs, env := reshapeEnviron(task, d.log)
+	d.ctx = ctx
+	// Specify the container ID or name
+	d.containerID = d.conn.ContainerName
+	if d.conn.DockerConnection == "" {
+		d.log.Debug("No explicit docker connection specified, using default: `unix:///var/run/docker.sock`")
+		d.conn.DockerConnection = "unix:///var/run/docker.sock"
+	}
+	cmd := append(
+		[]string{shell},
+		append(shellArgs, task.Command)...,
+	)
+	// Create an exec configuration
+	d.execCFG = &types.ExecConfig{
+		AttachStdout: true,
+		AttachStderr: true,
+		Privileged:   true,
+		Env:          env,
+		WorkingDir:   task.WorkingDirectory,
+		User:         task.UserName,
+		Cmd:          cmd,
+	}
+	return nil
+}
+
+// Connect establishes a connection to the Docker daemon.
+// It initializes the Docker client with the specified connection settings.
+// Returns:
+// - An error if the connection fails, otherwise nil.
+func (d *DockerAttachConnection) Connect() error {
+	cli, err := client.NewClientWithOpts(
+		client.WithHost(d.conn.DockerConnection),
+	)
+	if err != nil {
+		return err
+	}
+	d.cli = cli
+	return nil
+}
+
+// Execute runs the command in the Docker container and captures the output.
+// It creates an exec instance, attaches to it, and reads the command output.
+// Returns:
+// - A byte slice containing the command output.
+// - An error if the execution fails, otherwise nil.
+func (d *DockerAttachConnection) Execute() ([]byte, error) {
+	// Create the exec instance
+	exec, err := d.cli.ContainerExecCreate(d.ctx, d.containerID, *d.execCFG)
+	if err != nil {
+		return nil, err
+	}
+
+	// Attach to the exec instance
+	resp, err := d.cli.ContainerExecAttach(d.ctx, exec.ID, types.ExecStartCheck{})
+	if err != nil {
+		return nil, err
+	}
+	defer resp.Close()
+
+	writer := bytes.NewBuffer([]byte{})
+	// Print the command output
+	_, err = io.Copy(writer, resp.Reader)
+	if err != nil {
+		return nil, err
+	}
+	return writer.Bytes(), nil
+}
+
+// Disconnect closes the connection to the Docker daemon.
+// Returns:
+// - An error if the disconnection fails, otherwise nil.
+func (d *DockerAttachConnection) Disconnect() error {
+	return d.cli.Close()
+}

core/cmd_connection/docker_create.go

@@ -0,0 +1,180 @@
+package connection
+
+import (
+	"bytes"
+	"context"
+	"io"
+	"strings"
+
+	"github.com/docker/docker/api/types/container"
+	"github.com/docker/docker/api/types/network"
+	"github.com/docker/docker/client"
+	"github.com/sirupsen/logrus"
+
+	"github.com/FMotalleb/crontab-go/abstraction"
+	"github.com/FMotalleb/crontab-go/config"
+)
+
+// DockerCreateConnection is a struct that manages the creation and execution of Docker containers.
+type DockerCreateConnection struct {
+	conn            *config.TaskConnection
+	log             *logrus.Entry
+	cli             *client.Client
+	imageName       string
+	containerConfig *container.Config
+	hostConfig      *container.HostConfig
+	networkConfig   *network.NetworkingConfig
+	ctx             context.Context
+}
+
+// NewDockerCreateConnection initializes a new DockerCreateConnection instance.
+// Parameters:
+// - log: A logrus.Entry instance for logging.
+// - conn: A TaskConnection instance containing the connection configuration.
+// Returns:
+// - A new instance of DockerCreateConnection.
+func NewDockerCreateConnection(log *logrus.Entry, conn *config.TaskConnection) abstraction.CmdConnection {
+	return &DockerCreateConnection{
+		conn: conn,
+		log: log.WithFields(
+			logrus.Fields{
+				"connection":  "docker",
+				"docker-mode": "create",
+			},
+		),
+	}
+}
+
+// Prepare sets up the Docker container configuration based on the provided task.
+// Parameters:
+// - ctx: A context.Context instance for managing the lifecycle of the container.
+// - task: A Task instance containing the task configuration.
+// Returns:
+// - An error if the preparation fails, otherwise nil.
+func (d *DockerCreateConnection) Prepare(ctx context.Context, task *config.Task) error {
+	shell, shellArgs, env := reshapeEnviron(task, d.log)
+	d.ctx = ctx
+	if d.conn.DockerConnection == "" {
+		d.log.Debug("No explicit docker connection specified, using default: `unix:///var/run/docker.sock`")
+		d.conn.DockerConnection = "unix:///var/run/docker.sock"
+	}
+	cmd := append(
+		[]string{shell},
+		append(shellArgs, task.Command)...,
+	)
+	volumes := make(map[string]struct{})
+	for _, volume := range d.conn.Volumes {
+		inContainer := strings.Split(volume, ":")[1]
+		volumes[inContainer] = struct{}{}
+	}
+	// Create an exec configuration
+	d.containerConfig = &container.Config{
+		AttachStdout: true,
+		AttachStderr: true,
+		Env:          env,
+		WorkingDir:   task.WorkingDirectory,
+		User:         task.UserName,
+		Cmd:          cmd,
+		Image:        d.conn.ImageName,
+		Volumes:      volumes,
+		Entrypoint:   []string{},
+		Shell:        []string{},
+	}
+	d.hostConfig = &container.HostConfig{
+		Binds: d.conn.Volumes,
+		// AutoRemove: true,
+	}
+	endpointsConfig := make(map[string]*network.EndpointSettings)
+	for _, networkName := range d.conn.Networks {
+		endpointsConfig[networkName] = &network.EndpointSettings{}
+	}
+	d.networkConfig = &network.NetworkingConfig{
+		EndpointsConfig: endpointsConfig,
+	}
+	return nil
+}
+
+// Connect establishes a connection to the Docker daemon.
+// Returns:
+// - An error if the connection fails, otherwise nil.
+func (d *DockerCreateConnection) Connect() error {
+	cli, err := client.NewClientWithOpts(
+		client.WithHost(d.conn.DockerConnection),
+	)
+	if err != nil {
+		return err
+	}
+	d.cli = cli
+	return nil
+}
+
+// Execute creates, starts, and logs the output of the Docker container.
+// Returns:
+// - A byte slice containing the command output.
+// - An error if the execution fails, otherwise nil.
+func (d *DockerCreateConnection) Execute() ([]byte, error) {
+	ctx := d.ctx
+	// Create the exec instance
+	exec, err := d.cli.ContainerCreate(
+		ctx,
+		d.containerConfig,
+		d.hostConfig,
+		d.networkConfig,
+		nil,
+		d.conn.ContainerName,
+	)
+	d.log.Debugf("container created: %v, warnings: %v", exec, exec.Warnings)
+	if err != nil {
+		return nil, err
+	}
+	defer d.cli.ContainerRemove(ctx, exec.ID,
+		container.RemoveOptions{
+			Force: true,
+		},
+	)
+	err = d.cli.ContainerStart(d.log.Context, exec.ID,
+		container.StartOptions{},
+	)
+	d.log.Debugf("container started: %v", exec)
+	if err != nil {
+		return nil, err
+	}
+	starting := true
+	for starting {
+		_, err := d.cli.ContainerStats(ctx, exec.ID, false)
+		if err == nil {
+			starting = false
+		}
+	}
+	d.log.Debugf("container ready to attach: %v", exec)
+	// Attach to the exec instance
+	resp, err := d.cli.ContainerLogs(
+		ctx,
+		exec.ID,
+		container.LogsOptions{
+			ShowStdout: true,
+			ShowStderr: true,
+			Follow:     false,
+			Details:    true,
+		},
+	)
+	if err != nil {
+		return nil, err
+	}
+	defer resp.Close()
+
+	writer := bytes.NewBuffer([]byte{})
+	// Print the command output
+	_, err = io.Copy(writer, resp)
+	if err != nil {
+		return writer.Bytes(), err
+	}
+	return writer.Bytes(), nil
+}
+
+// Disconnect closes the connection to the Docker daemon.
+// Returns:
+// - An error if the disconnection fails, otherwise nil.
+func (d *DockerCreateConnection) Disconnect() error {
+	return d.cli.Close()
+}