Move "export" to daemon/export.go

This is part of an effort to break apart the deprecated server/ package

Docker-DCO-1.1-Signed-off-by: Solomon Hykes <solomon@docker.com> (github: shykes)
Upstream-commit: 8031c23b0f492b6f62dfc226dbf9b3d051d9546a
Component: engine

components/engine/daemon/export.go

@@ -0,0 +1,30 @@
+package daemon
+
+import (
+	"io"
+
+	"github.com/docker/docker/engine"
+)
+
+func (daemon *Daemon) ContainerExport(job *engine.Job) engine.Status {
+	if len(job.Args) != 1 {
+		return job.Errorf("Usage: %s container_id", job.Name)
+	}
+	name := job.Args[0]
+	if container := daemon.Get(name); container != nil {
+		data, err := container.Export()
+		if err != nil {
+			return job.Errorf("%s: %s", name, err)
+		}
+		defer data.Close()
+
+		// Stream the entire contents of the container (basically a volatile snapshot)
+		if _, err := io.Copy(job.Stdout, data); err != nil {
+			return job.Errorf("%s: %s", name, err)
+		}
+		// FIXME: factor job-specific LogEvent to engine.Job.Run()
+		job.Eng.Job("log", "export", container.ID, daemon.Repositories().ImageName(container.Image)).Run()
+		return engine.StatusOK
+	}
+	return job.Errorf("No such container: %s", name)
+}