Future send()

in lib/src/http.dart [172:232]
42 lines of code
18 McCabe index (conditional complexity)

  Future<http.StreamedResponse> send(http.BaseRequest request) async {
    late http.StreamedResponse streamedResponse;
    try {
      streamedResponse = await _inner.send(request);
    } on SocketException catch (error, stackTraceOrNull) {
      // Work around issue 23008.
      var stackTrace = stackTraceOrNull;

      if (error.osError == null) rethrow;

      // Handle error codes known to be related to DNS or SSL issues. While it
      // is tempting to handle these error codes before retrying, saving time
      // for the end-user, it is known that DNS lookups can fail intermittently
      // in some cloud environments. Furthermore, since these error codes are
      // platform-specific (undocumented) and essentially cargo-culted along
      // skipping retries may lead to intermittent issues that could be fixed
      // with a retry. Failing to retry intermittent issues is likely to cause
      // customers to wrap pub in a retry loop which will not improve the
      // end-user experience.
      if (error.osError!.errorCode == 8 ||
          error.osError!.errorCode == -2 ||
          error.osError!.errorCode == -5 ||
          error.osError!.errorCode == 11001 ||
          error.osError!.errorCode == 11004) {
        fail('Could not resolve URL "${request.url.origin}".', error,
            stackTrace);
      } else if (error.osError!.errorCode == -12276) {
        fail(
            'Unable to validate SSL certificate for '
            '"${request.url.origin}".',
            error,
            stackTrace);
      } else {
        rethrow;
      }
    }

    var status = streamedResponse.statusCode;
    // 401 responses should be handled by the OAuth2 client. It's very
    // unlikely that they'll be returned by non-OAuth2 requests. We also want
    // to pass along 400 responses from the token endpoint.
    var tokenRequest = streamedResponse.request!.url == oauth2.tokenEndpoint;
    if (status < 400 || status == 401 || (status == 400 && tokenRequest)) {
      return streamedResponse;
    }

    if (status == 406 && request.headers['Accept'] == pubApiHeaders['Accept']) {
      fail('Pub ${sdk.version} is incompatible with the current version of '
          '${request.url.host}.\n'
          'Upgrade pub to the latest version and try again.');
    }

    if (status == 500 &&
        (request.url.host == 'pub.dartlang.org' ||
            request.url.host == 'storage.googleapis.com')) {
      fail('HTTP error 500: Internal Server Error at ${request.url}.\n'
          'This is likely a transient error. Please try again later.');
    }

    throw PubHttpException(await http.Response.fromStream(streamedResponse));
  }