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

81 lines
1.4 KiB
Go

package main
import (
"flag"
"io"
"log"
"net/http"
"os"
gopath "path"
"path/filepath"
"time"
)
var (
upstreamURL = flag.String("upstream", "https://direktil.novit.nc/dist", "Upstream server for dist elements")
)
func (ctx *renderContext) distFetch(path ...string) (outPath string, err error) {
outPath = ctx.distFilePath(path...)
if _, err = os.Stat(outPath); err == nil {
return
} else if !os.IsNotExist(err) {
return
}
subPath := gopath.Join(path...)
log.Print("need to fetch ", subPath)
if err = os.MkdirAll(filepath.Dir(outPath), 0755); err != nil {
return
}
fullURL := *upstreamURL + "/" + subPath
resp, err := http.Get(fullURL)
if err != nil {
return
}
tempOutPath := filepath.Join(filepath.Dir(outPath), "._part_"+filepath.Base(outPath))
done := make(chan error, 1)
go func() {
defer resp.Body.Close()
defer close(done)
out, err := os.Create(tempOutPath)
if err != nil {
done <- err
return
}
defer out.Close()
_, err = io.Copy(out, resp.Body)
done <- err
}()
wait:
select {
case <-time.After(10 * time.Second):
log.Print("still fetching ", subPath, "...")
goto wait
case err = <-done:
if err != nil {
log.Print("fetch of ", subPath, " failed: ", err)
os.Remove(tempOutPath)
return
}
log.Print("fetch of ", subPath, " finished")
}
err = os.Rename(tempOutPath, outPath)
return
}