Function encodePack

lib/pack-codec.js:245–281

(emit)

exports.encodePack = encodePack;
function encodePack(emit) {
  var sha1sum = sha1();
  var left;
  return function (item) {
    if (item === undefined) {
      if (left !== 0) throw new Error("Some items were missing");
      return emit();
    }
    if (typeof item.num === "number") {
      if (left !== undefined) throw new Error("Header already sent");
      left = item.num;
      write(packHeader(item.num));
    }
    else if (typeof item.type === "string" && bodec.isBinary(item.body)) {
      // The header must be sent before items.
      if (typeof left !== "number") throw new Error("Headers not sent yet");

      // Make sure we haven't sent all the items already
      if (!left) throw new Error("All items already sent");

      // Send the item in packstream format
      write(packFrame(item));

      // Send the checksum after the last item
      if (!--left) {
        emit(bodec.fromHex(sha1sum.digest()));
      }
    }
    else {
      throw new Error("Invalid item");
    }
  };
  function write(chunk) {
    sha1sum.update(chunk);
    emit(chunk);
  }
}

function packHeader(length) {
  return bodec.fromArray([