export default (path, accessToken, fetchOptions: any = {}) => {
  const headers = { "X-XAPP-TOKEN": config.GRAVITY_XAPP_TOKEN }
  let fetchParams = fetchOptions

  const requestIDs = fetchOptions.requestIDs
  if (requestIDs) {
    fetchParams = omit(fetchOptions, "requestIDs")
    assign(headers, requestIDHeaders(requestIDs))
  }

  if (accessToken) assign(headers, { "X-ACCESS-TOKEN": accessToken })

  return fetch(
    urljoin(
      resolveBlueGreen(
        GRAVITY_API_BASE!,
        GRAVITY_API_BASE_GREEN!,
        GRAVITY_API_PERCENT_REDIRECT
      ),
      path
    ),
    assign({}, fetchParams, { headers })
  )
}

export const createExchangeLink = () => {
  const httpLink = createHttpLink({
    fetch,
    uri: urljoin(EXCHANGE_API_BASE, "graphql"),
  })

  const authMiddleware = setContext((_request, context) => {
    const locals = context.graphqlContext && context.graphqlContext.res.locals
    const tokenLoader = locals && locals.dataLoaders.exchangeTokenLoader
    const headers = { ...(locals && requestIDHeaders(locals.requestIDs)) }
    // If a token loader exists for Exchange (i.e. this is an authenticated request), use that token to make
    // authenticated requests to Exchange.
    if (tokenLoader) {
      return tokenLoader().then(({ token }) => {
        return {
          headers: Object.assign(headers, { Authorization: `Bearer ${token}` }),
        }
      })
    }
    // Exchange uses no authentication for now
    return { headers }
  })

  return middlewareLink.concat(authMiddleware).concat(httpLink)
}

      map(([_session, content]) => {
        const { response } = content;

        if (content.status > 299 || typeof response === "string") {
          // hack around this old hack around for creating a notebook
          // from the directory ideally this would be in a proper epic
          // instead of leaky async code here
          const message: string[] = ["Failed to create notebook due to: "];

          if (typeof response === "string") {
            message.push(response);
          } else {
            message.push(JSON.stringify(response));
          }

          alert(message.join(""));

          return;
        }

        const url: string = urljoin(
          props.appBase,
          // Actual file
          response.path
        );

        // Always open new notebooks in new windows
        const win = window.open(url, "_blank");

        // If they block pop-ups, then we weren't allowed to open the window
        if (win === null) {
          window.location.href = url;
        }
      })

export const createLewittLink = () => {
  const httpLink = createHttpLink({
    fetch,
    uri: urljoin(LEWITT_API_BASE, "graphql"),
  })

  const authMiddleware = setContext((_request, context) => {
    const locals = context.graphqlContext && context.graphqlContext.res.locals
    const headers = { ...(locals && requestIDHeaders(locals.requestIDs)) }
    // Lewitt uses no authentication for now
    return { headers }
  })

  return middlewareLink.concat(authMiddleware).concat(httpLink)
}

          map(() => {
            /*
             * Modifying the url's file name in the browser.
             * This effects back button behavior.
             * Is there a better way to accomplish this?
             */
            window.history.replaceState(
              {},
              filepath,
              urljoin(host.basePath, `/nteract/edit${filepath}`)
            );

            return actions.changeContentNameFulfilled({
              contentRef: action.payload.contentRef,
              filepath: action.payload.filepath,
              prevFilePath
            });
          }),

export const formWebSocketURL = (
  serverConfig: ServerConfig,
  kernelID: string,
  sessionID?: string
): string => {
  const params = new URLSearchParams();
  if (serverConfig.token) {
    params.append("token", serverConfig.token);
  }
  if (sessionID) {
    params.append("session_id", sessionID);
  }

  const q = params.toString();
  const suffix = q !== "" ? `?${q}` : "";

  const url = urljoin(
    serverConfig.endpoint || "",
    `/api/kernels/${kernelID}/channels${suffix}`
  );

  return url.replace(/^http(s)?/, "ws$1");
};

const formURI = (path: string) => urljoin("/api/contents/", path);