func (p *PostProcessor) PostProcess(ui packer.Ui, artifact packer.Artifact) (packer.Artifact, bool, error) {
if artifact.BuilderId() != dockertag.BuilderId {
err := fmt.Errorf(
"Unknown artifact type: %s\nCan only build with Dockerfile from Docker tag artifacts.",
artifact.BuilderId())
return nil, false, err
}
p.config.From = artifact.Id()
template_str := `FROM {{ .From }}
{{ if .Maintainer }}MAINTAINER {{ .Maintainer }}
{{ end }}{{ if .Cmd }}CMD {{ process .Cmd }}
{{ end }}{{ if .Label }}{{ range $k, $v := .Label }}LABEL "{{ $k }}"="{{ $v }}"
{{ end }}{{ end }}{{ if .Expose }}EXPOSE {{ join .Expose " " }}
{{ end }}{{ if .Env }}{{ range $k, $v := .Env }}ENV {{ $k }} {{ $v }}
{{ end }}{{ end }}{{ if .Entrypoint }}ENTRYPOINT {{ process .Entrypoint }}
{{ end }}{{ if .Volume }}VOLUME {{ process .Volume }}
{{ end }}{{ if .User }}USER {{ .User }}
{{ end }}{{ if .WorkDir }}WORKDIR {{ .WorkDir }}{{ end }}`
dockerfile := new(bytes.Buffer)
template_writer := bufio.NewWriter(dockerfile)
tmpl, err := template.New("Dockerfile").Funcs(template.FuncMap{
"process": p.processVar,
"join": strings.Join,
}).Parse(template_str)
if err != nil {
return nil, false, err
}
err = tmpl.Execute(template_writer, p.config)
if err != nil {
return nil, false, err
}
template_writer.Flush()
log.Printf("Dockerfile:\n%s", dockerfile.String())
driver := p.Driver
if driver == nil {
// If no driver is set, then we use the real driver
driver = &DockerDriver{&docker.DockerDriver{Ctx: &p.config.ctx, Ui: ui}}
}
ui.Message("Building image from Dockerfile")
id, err := driver.BuildImage(dockerfile)
if err != nil {
return nil, false, err
}
ui.Message("Destroying previously tagged image: " + p.config.From)
err = artifact.Destroy()
if err != nil {
return nil, false, err
}
ui.Message("Tagging new image, " + id + ", as " + p.config.From)
err = driver.TagImage(id, p.config.From, true)
if err != nil {
return nil, false, err
}
// Build the artifact
artifact = &docker.ImportArtifact{
BuilderIdValue: dockertag.BuilderId,
Driver: driver,
IdValue: p.config.From,
}
return artifact, true, nil
}