[Smtk-developers] Operators and changes to Logger

[David Thompson]

Hi all,

Last night I pushed changes to master that add some methods to smtk::io::Logger for easier debugging as well as inter-process communication of operator results:

+ void setFlushToStream(
    std::ostream* output, bool ownFile, bool includePast);
+ bool setFlushToFile( std::string filename, bool includePast);
+ void setFlushToStdout(bool includePast);
+ void setFlushToStderr(bool includePast);

Each Logger now stores an ostream* (which it may own and delete when modified). If non-NULL, then each time a record is added or another Logger is appended, the new records are printed to the stream and the stream flushed. Thus a logger created at startup and set to flush to a temporary file can be used for debugging.

The changes also modify the model manager so that it owns a logger. Model operators now record results of modeling operations to their manager's log and these are automatically appended to the OperatorResult attribute's "log" item (a StringItem).

Finally, the smtk::io::{Import,Export}JSON classes can serialize/deserialize log records to/from JSON. Applications wishing to present informational or error messages from Operators can:

  OperatorPtr op; // = model->op("set property"), for instance.
  OperatorResult res = op->operate();
  StringItemPtr opmsg = res->findString("log");
  if (opmsg->numberOfValues() > 0)
    {
    Logger oplog;
    ImportJSON::ofLogger(cJSON_Parse(opmsg->value()), oplog);
    // Now display oplog entries in the GUI
    }

David