Logging Categories

[rarutter]

Our existing console logging levels are the default ones shipped with Boost, and don't always match our uses well. This is roughly how they are set up:

• fatal: significant errors for which the model must stop as well as information that might cause the user to want to stop the model
• err/warn: not clearly separated, includes errors that don't require the model to stop but should be investigated at some point
• note/info: also not clearly separated, a catch-all for notes that aren't errors but aren't as detailed as what goes into debug
• debug: everything

I would like to clean up our log messages, which will include redefining categories and reassigning some existing statements to ones that fit better. Here is my rough draft for new categories:

• fatal: Significant problems, the model must stop.
  • "Unable to find input file"
• monitor: High-level information for a user casually monitoring a run
  • "Running Equilibrium x years"
  • "Skipping cell x,y"
• warn: Errors that are not serious enough to stop but should be investigated. Will usually be scientific/data errors instead of mechanical.
  • "Unknown datatype: '" << the_type << "'. Returning empty vector."
  • "Adjacent fronts should be different!"
• info: General information, a more detailed version of monitor
  • "Update model settings based on command line flags/options..."
  • "Searching file for community: " << cmtstr
• debug: Everything

We should also look into expanding our use of logging scopes, to hopefully make the logs more pertinent to a specific use. For example, to log more detailed
messages about soil structure, but skip vegetation.

Thoughts and suggestions are welcome!