NotebookServer.java

  private void runParagraph(NotebookSocket conn, HashSet<String> userAndRoles, Notebook notebook,
      Message fromMessage) throws IOException {
    final String paragraphId = (String) fromMessage.get("id");
    if (paragraphId == null) {
      return;
    }

    String noteId = getOpenNoteId(conn);
    final Note note = notebook.getNote(noteId);
    NotebookAuthorization notebookAuthorization = notebook.getNotebookAuthorization();
    if (!notebookAuthorization.isWriter(noteId, userAndRoles)) {
      permissionError(conn, "write", fromMessage.principal,
          userAndRoles, notebookAuthorization.getWriters(noteId));
      return;
    }

    Paragraph p = note.getParagraph(paragraphId);
    String text = (String) fromMessage.get("paragraph");
    p.setText(text);
    p.setTitle((String) fromMessage.get("title"));
    if (!fromMessage.principal.equals("anonymous")) {
      AuthenticationInfo authenticationInfo = new AuthenticationInfo(fromMessage.principal,
          fromMessage.ticket);
      p.setAuthenticationInfo(authenticationInfo);

    } else {
      p.setAuthenticationInfo(new AuthenticationInfo());
    }

    Map<String, Object> params = (Map<String, Object>) fromMessage
       .get("params");
    p.settings.setParams(params);
    Map<String, Object> config = (Map<String, Object>) fromMessage
       .get("config");
    p.setConfig(config);
    // if it's the last paragraph, let's add a new one
    boolean isTheLastParagraph = note.isLastParagraph(p.getId());
    if (!(text.trim().equals(p.getMagic()) || Strings.isNullOrEmpty(text)) &&
        isTheLastParagraph) {
      note.addParagraph();
    }

    AuthenticationInfo subject = new AuthenticationInfo(fromMessage.principal);
    note.persist(subject);
    try {
      note.run(paragraphId);
    } catch (Exception ex) {
      LOG.error("Exception from run", ex);
      if (p != null) {
        p.setReturn(
            new InterpreterResult(InterpreterResult.Code.ERROR, ex.getMessage()),
            ex);
        p.setStatus(Status.ERROR);
        broadcast(note.getId(), new Message(OP.PARAGRAPH).put("paragraph", p));
      }
    }
  }