// DecompressAndLoad will load or fetch a graph from the given path, decompress
// it, and then call the given load function to process the decompressed graph.
// If no loadFn is provided, db.Load is called.
func DecompressAndLoad(qw graph.QuadWriter, cfg *config.Config, path, typ string, loadFn func(graph.QuadWriter, *config.Config, quad.Reader) error) error {
var r io.Reader
if path == "" {
path = cfg.DatabasePath
}
if path == "" {
return nil
}
u, err := url.Parse(path)
if err != nil || u.Scheme == "file" || u.Scheme == "" {
// Don't alter relative URL path or non-URL path parameter.
if u.Scheme != "" && err == nil {
// Recovery heuristic for mistyping "file://path/to/file".
path = filepath.Join(u.Host, u.Path)
}
f, err := os.Open(path)
if err != nil {
return fmt.Errorf("could not open file %q: %v", path, err)
}
defer f.Close()
r = f
} else {
res, err := client.Get(path)
if err != nil {
return fmt.Errorf("could not get resource <%s>: %v", u, err)
}
defer res.Body.Close()
r = res.Body
}
r, err = Decompressor(r)
if err != nil {
if err == io.EOF {
return nil
}
return err
}
var dec quad.ReadCloser
switch typ {
case "cquad", "cquads":
dec = cquads.NewDecoder(r)
case "nquad", "nquads":
dec = nquads.NewDecoder(r)
default:
format := quad.FormatByName(typ)
if format == nil || format.Reader == nil {
return fmt.Errorf("unknown quad format %q", typ)
}
dec = format.Reader(r)
}
defer dec.Close()
if loadFn != nil {
return loadFn(qw, cfg, dec)
}
return db.Load(qw, cfg, dec)
}
func (api *Api) ServeV1WriteNQuad(w http.ResponseWriter, r *http.Request, params httprouter.Params) int {
if api.config.ReadOnly {
return FormatJson400(w, "Database is read-only.")
}
formFile, _, err := r.FormFile("NQuadFile")
if err != nil {
glog.Errorln(err)
return FormatJsonError(w, 500, "Couldn't read file: "+err.Error())
}
defer formFile.Close()
blockSize, blockErr := strconv.ParseInt(r.URL.Query().Get("block_size"), 10, 64)
if blockErr != nil {
blockSize = int64(api.config.LoadSize)
}
dec := nquads.NewDecoder(formFile)
var (
n int
block = make([]*quad.Quad, 0, blockSize)
)
for {
t, err := dec.Unmarshal()
if err != nil {
if err == io.EOF {
break
}
panic("what can do this here?") // FIXME(kortschak)
}
block = append(block, t)
n++
if len(block) == cap(block) {
api.ts.AddTripleSet(block)
block = block[:0]
}
}
api.ts.AddTripleSet(block)
fmt.Fprintf(w, "{\"result\": \"Successfully wrote %d triples.\"}", n)
return 200
}