Configuration

Cornerstone Core accepts configuration through its init function. Pass the configuration on the first call to init; subsequent calls return immediately after Cornerstone has been initialized.

Logging

Cornerstone writes its messages with loglevel, through the same log root as dcmjs. Configure the logs with the loglevel interface, not with the init configuration. Thus one interface controls the logs of Cornerstone, of dcmjs, and of the other components of your application.

import { logging } from '@cornerstonejs/utils';

logging.log.getLogger('cs3d.dicomImageLoader.wadouri').setLevel('info');

The levels, from the most messages to the fewest messages, are:

• trace
• debug
• info
• warn
• error
• silent

Logger names

A logger name has this structure:

cs3d.<PACKAGE>.<PATH>.<FILEORAREA>

• cs3d is the root of all Cornerstone logs.
• <PACKAGE> is the package, for example core, tools, dicomImageLoader, niftiVolumeLoader, polymorphicSegmentation, labelmapInterpolation, adapters, metadata or ai.
• <PATH> is the folder in the source of that package. It can have more than one part, and a file at the root of the package has no path.
• <FILEORAREA> is the file, or the area of the code when the messages come from more than one file.

Examples of names:

• cs3d.core.RenderingEngine.StackViewport
• cs3d.core.utilities.VoxelManager
• cs3d.dicomImageLoader.wadouri
• cs3d.adapters.Cornerstone3D.MeasurementReport

Two loggers are not below cs3d: consistency.dicom and consistency.image. These loggers are on the root of dcmjs, because dcmjs writes the same consistency messages.

Set a level

Logger names are independent strings; dots in a name do not create a parent and child relationship. Setting a named logger's level therefore affects only that exact logger. To find the loggers that exist, use logging.log.getLoggers().

import { logging } from '@cornerstonejs/utils';

// One exact logger
logging.log.getLogger('cs3d.core.RenderingEngine').setLevel('debug');

// All existing loggers whose names start with an area prefix
const prefix = 'cs3d.core.RenderingEngine';
Object.entries(logging.log.getLoggers()).forEach(([name, logger]) => {
  if (name === prefix || name.startsWith(`${prefix}.`)) {
    logger.setLevel('debug');
  }
});

// Update the root, then update existing loggers that do not have their own level
logging.log.setLevel('warn');
logging.log.rebuild();

You can set a level at any time, and the new level is immediately applicable. Named loggers created after a root level change inherit the new root level. Named loggers that already exist keep their inherited level until you call logging.log.rebuild(). Thus you can also give this control to your users, for example in a menu for support.

Send the logs to a different location

loglevel lets you replace the function that makes each log method. Use this to send the messages to a server, to a file, or to the interface of your application. Call setLevel after you replace the function, because the new methods are made at that time.

import { logging } from '@cornerstonejs/utils';

const logger = logging.log.getLogger('cs3d.core.RenderingEngine');
const originalFactory = logger.methodFactory;

logger.methodFactory = (methodName, level, loggerName) => {
  const originalMethod = originalFactory(methodName, level, loggerName);

  return (...args) => {
    originalMethod(...args);

    if (methodName === 'warn' || methodName === 'error') {
      myTelemetry.send({ logger: String(loggerName), methodName, args });
    }
  };
};

logger.setLevel(logger.getLevel());