Add SimpleDocker backend

pkg/compiler/backend/simpledocker.go

@@ -0,0 +1,94 @@
+// Copyright © 2019 Ettore Di Giacinto <mudler@gentoo.org>
+//
+// This program is free software; you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation; either version 2 of the License, or
+// (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License along
+// with this program; if not, see <http://www.gnu.org/licenses/>.
+
+package backend
+
+import (
+	"os/exec"
+
+	"github.com/mudler/luet/pkg/compiler"
+	. "github.com/mudler/luet/pkg/logger"
+
+	"github.com/pkg/errors"
+)
+
+type SimpleDocker struct{}
+
+func NewSimpleDockerBackend() compiler.CompilerBackend {
+	return &SimpleDocker{}
+}
+
+// TODO: Missing still: labels, and build args expansion
+func (*SimpleDocker) BuildImage(opts compiler.CompilerBackendOptions) error {
+	name := opts.ImageName
+	path := opts.SourcePath
+	dockerfileName := opts.DockerFileName
+	buildarg := []string{"build", "-f", dockerfileName, "-t", name, "."}
+	Spinner(22)
+	Debug("Building image "+name+" - running docker with: ", buildarg)
+	cmd := exec.Command("docker", buildarg...)
+	cmd.Dir = path
+	out, err := cmd.CombinedOutput()
+	if err != nil {
+		return errors.Wrap(err, "Failed building image: "+string(out))
+	}
+	SpinnerStop()
+	Info(string(out))
+	return nil
+}
+
+func (*SimpleDocker) RemoveImage(opts compiler.CompilerBackendOptions) error {
+	name := opts.ImageName
+	buildarg := []string{"rmi", name}
+	Spinner(22)
+	out, err := exec.Command("docker", buildarg...).CombinedOutput()
+	if err != nil {
+		return errors.Wrap(err, "Failed removing image: "+string(out))
+	}
+	SpinnerStop()
+	Info(string(out))
+	return nil
+}
+
+func (s *SimpleDocker) ImageDefinitionToTar(opts compiler.CompilerBackendOptions) error {
+	if err := s.BuildImage(opts); err != nil {
+		return errors.Wrap(err, "Failed building image")
+	}
+	if err := s.ExportImage(opts); err != nil {
+		return errors.Wrap(err, "Failed exporting image")
+	}
+	if err := s.RemoveImage(opts); err != nil {
+		return errors.Wrap(err, "Failed removing image")
+	}
+	return nil
+}
+
+func (*SimpleDocker) ExportImage(opts compiler.CompilerBackendOptions) error {
+	name := opts.ImageName
+	path := opts.Destination
+
+	buildarg := []string{"save", name, "-o", path}
+	Spinner(22)
+	Debug("Saving image "+name+" - running docker with: ", buildarg)
+	out, err := exec.Command("docker", buildarg...).CombinedOutput()
+	if err != nil {
+		return errors.Wrap(err, "Failed exporting image: "+string(out))
+	}
+	SpinnerStop()
+	Info(string(out))
+	return nil
+}
+
+// TODO: Use container-diff (https://github.com/GoogleContainerTools/container-diff) for checking out layer diffs