func FileHandler(store fs.LocalStore) http.HandlerFunc {
return func(resp http.ResponseWriter, req *http.Request) {
setBinaryResp(resp)
strong, hasStrong := mux.Vars(req)["strong"]
if !hasStrong {
writeResponseError(resp, http.StatusInternalServerError,
"Missing parameter: strong")
return
}
offsetStr, hasOffset := mux.Vars(req)["offset"]
if !hasOffset {
writeResponseError(resp, http.StatusInternalServerError,
"Missing parameter: offset")
return
}
offset, err := strconv.Atoi64(offsetStr)
if err != nil {
writeResponseError(resp, http.StatusInternalServerError,
fmt.Sprintf("Invalid format for length: %s", offsetStr))
return
}
lengthStr, hasLength := mux.Vars(req)["length"]
if !hasLength {
writeResponseError(resp, http.StatusInternalServerError,
"Missing parameter: length")
return
}
length, err := strconv.Atoi64(lengthStr)
if err != nil {
writeResponseError(resp, http.StatusInternalServerError,
fmt.Sprintf("Invalid format for length: %s", lengthStr))
return
}
buffer := bytes.NewBuffer([]byte{})
n, err := store.ReadInto(strong, offset, length, buffer)
if err != nil {
writeResponseError(resp, http.StatusInternalServerError, err.String())
return
}
if n < length {
writeResponseError(resp, http.StatusInternalServerError, io.ErrShortWrite.String())
}
resp.Write(buffer.Bytes())
}
}
