Future close()

in lib/src/http_impl.dart [1300:1379]
64 lines of code
16 McCabe index (conditional complexity)

  Future close() {
    // If we are already closed, return that future.
    if (_closeFuture != null) return _closeFuture;
    // If we earlier saw an error, return immediate. The notification to
    // _Http*Connection is already done.
    if (_socketError) return Future.value(outbound);
    if (outbound._isConnectionClosed) return Future.value(outbound);
    if (!headersWritten && !ignoreBody) {
      if (outbound.headers.contentLength == -1) {
        // If no body was written, ignoreBody is false (it's not a HEAD
        // request) and the content-length is unspecified, set contentLength to
        // 0.
        outbound.headers.chunkedTransferEncoding = false;
        outbound.headers.contentLength = 0;
      } else if (outbound.headers.contentLength > 0) {
        var error = HttpException(
            "No content even though contentLength was specified to be "
            "greater than 0: ${outbound.headers.contentLength}.",
            uri: outbound._uri);
        _doneCompleter.completeError(error);
        return _closeFuture = Future.error(error);
      }
    }
    // If contentLength was specified, validate it.
    if (contentLength != null) {
      if (_bytesWritten < contentLength) {
        var error = HttpException(
            "Content size below specified contentLength. "
            " $_bytesWritten bytes written but expected "
            "$contentLength.",
            uri: outbound._uri);
        _doneCompleter.completeError(error);
        return _closeFuture = Future.error(error);
      }
    }

    Future finalize() {
      // In case of chunked encoding (and gzip), handle remaining gzip data and
      // append the 'footer' for chunked encoding.
      if (chunked) {
        if (_gzip) {
          _gzipAdd = socket.add;
          if (_gzipBufferLength > 0) {
            _gzipSink
                .add(Uint8List.view(_gzipBuffer.buffer, 0, _gzipBufferLength));
          }
          _gzipBuffer = null;
          _gzipSink.close();
          _gzipAdd = null;
        }
        _addChunk(_chunkHeader(0), socket.add);
      }
      // Add any remaining data in the buffer.
      if (_length > 0) {
        socket.add(Uint8List.view(_buffer.buffer, 0, _length));
      }
      // Clear references, for better GC.
      _buffer = null;
      // And finally flush it. As we support keep-alive, never close it from
      // here. Once the socket is flushed, we'll be able to reuse it (signaled
      // by the 'done' future).
      return socket.flush().then((_) {
        _doneCompleter.complete(socket);
        return outbound;
      }, onError: (error, StackTrace stackTrace) {
        _doneCompleter.completeError(error, stackTrace);
        if (_ignoreError(error)) {
          return outbound;
        } else {
          throw error;
        }
      });
    }

    var future = writeHeaders();
    if (future != null) {
      return _closeFuture = future.whenComplete(finalize);
    }
    return _closeFuture = finalize();
  }