local-server/initrd.go
2018-06-12 21:09:47 +11:00

153 lines
2.9 KiB
Go

package main
import (
"bytes"
"fmt"
"io"
"log"
"net/http"
"os"
"time"
cpio "github.com/cavaliercoder/go-cpio"
yaml "gopkg.in/yaml.v2"
)
func renderConfig(w http.ResponseWriter, r *http.Request, ctx *renderContext) error {
log.Printf("sending config for %q", ctx.Host.Name)
_, cfg, err := ctx.Config()
if err != nil {
return err
}
ba, err := yaml.Marshal(cfg)
if err != nil {
return err
}
w.Header().Set("Content-Type", "application/yaml")
http.ServeContent(w, r, "config.yaml", time.Unix(0, 0), bytes.NewReader(ba))
return nil
}
func renderStaticPods(w http.ResponseWriter, r *http.Request, ctx *renderContext) error {
log.Printf("sending static-pods for %q", ctx.Host.Name)
ba, err := ctx.StaticPods()
if err != nil {
return err
}
w.Header().Set("Content-Type", "application/yaml") // XXX can also be JSON
http.ServeContent(w, r, "static-pods", time.Unix(0, 0), bytes.NewReader(ba))
return nil
}
func renderCtx(w http.ResponseWriter, r *http.Request, ctx *renderContext, what string,
create func(out io.Writer, ctx *renderContext) error) error {
log.Printf("sending %s for %q", what, ctx.Host.Name)
tag, err := ctx.Tag()
if err != nil {
return err
}
// get it or create it
content, meta, err := casStore.GetOrCreate(tag, what, func(out io.Writer) error {
log.Printf("building %s for %q", what, ctx.Host.Name)
return create(out, ctx)
})
if err != nil {
return err
}
// serve it
http.ServeContent(w, r, what, meta.ModTime(), content)
return nil
}
func buildInitrd(out io.Writer, ctx *renderContext) error {
_, cfg, err := ctx.Config()
if err != nil {
return err
}
// send initrd basis
initrdPath, err := ctx.distFetch("initrd", ctx.Group.Initrd)
if err != nil {
return err
}
err = writeFile(out, initrdPath)
if err != nil {
return err
}
// and our extra archive
archive := cpio.NewWriter(out)
// - required dirs
for _, dir := range []string{
"boot",
"boot/current",
"boot/current/layers",
} {
archive.WriteHeader(&cpio.Header{
Name: dir,
Mode: 0600 | cpio.ModeDir,
})
}
// - the layers
for _, layer := range cfg.Layers {
layerVersion := ctx.Group.Versions[layer]
if layerVersion == "" {
return fmt.Errorf("layer %q not mapped to a version", layer)
}
path, err := ctx.distFetch("layers", layer, layerVersion)
if err != nil {
return err
}
stat, err := os.Stat(path)
if err != nil {
return err
}
archive.WriteHeader(&cpio.Header{
Name: "boot/current/layers/" + layer + ".fs",
Mode: 0600,
Size: stat.Size(),
})
if err = writeFile(archive, path); err != nil {
return err
}
}
// - the configuration
ba, err := yaml.Marshal(cfg)
if err != nil {
return err
}
archive.WriteHeader(&cpio.Header{
Name: "boot/config.yaml",
Mode: 0600,
Size: int64(len(ba)),
})
archive.Write(ba)
// finalize the archive
archive.Flush()
archive.Close()
return nil
}