How to use the karma.constants.LOG_INFO function in karma

require('karma-jasmine-html-reporter'),
      require('karma-coverage-istanbul-reporter'),
      require('@angular-devkit/build-angular/plugins/karma')
    ],
    client: {
      clearContext: false // leave Jasmine Spec Runner output visible in browser
    },
    coverageIstanbulReporter: {
      dir: join(__dirname, '../../coverage'),
      reports: ['html', 'lcovonly'],
      fixWebpackSourcePaths: true
    },
    reporters: ['progress', 'kjhtml'],
    port: 9876,
    colors: true,
    logLevel: constants.LOG_INFO,
    autoWatch: true,
    browsers: ['Chrome'],
    singleRun: true
  };
};

require('karma-jasmine-html-reporter'),
      require('karma-coverage-istanbul-reporter'),
      require('@angular-devkit/build-angular/plugins/karma')
    ],
    client: {
      clearContext: false // leave Jasmine Spec Runner output visible in browser
    },
    coverageIstanbulReporter: {
      dir: join(__dirname, '../../coverage'),
      reports: ['html', 'lcovonly'],
      fixWebpackSourcePaths: true
    },
    reporters: ['progress', 'kjhtml'],
    port: 9876,
    colors: true,
    logLevel: constants.LOG_INFO,
    autoWatch: false,
    browsers: ['Chrome'],
    singleRun: true
  };
};

plugins: [
        'karma-mocha',
        'karma-mocha-reporter',
        'karma-firefox-launcher',
        'karma-coverage-istanbul-reporter'
      ],

      browserConsoleLogOptions: {
        level: 'log',
        format: '%b %T: %m',
        terminal: true
      },

      reporters,
      colors: true,
      logLevel: constants.LOG_INFO,

      browsers: ['FirefoxHeadless'],

      coverageIstanbulReporter: {
        reports: ['text', 'text-summary', 'lcovonly'],
        dir: nPath.resolve('coverage'),
        combineBrowserReports: true,
        'report-config': {
          lcovonly: {
            dir: 'coverage',
            subdir: 'lcov'
          }
        }
      },

      // Continuous Integration mode

// preprocess matching files before serving them to the browser
    // available preprocessors: https://npmjs.org/browse/keyword/karma-preprocessor
    preprocessors: {
      'test/test_index.js': ['webpack', 'sourcemap']
    },

    // web server port
    port: 9876,

    // enable / disable colors in the output (reporters and logs)
    colors: true,

    // level of logging
    // possible values: LOG_DISABLE || LOG_ERROR || LOG_WARN || LOG_INFO || LOG_DEBUG
    logLevel: karmaConstants.LOG_INFO,

    // enable / disable watching file and executing tests whenever any file changes
    autoWatch: true,

    reporters: ['mocha'],
    mochaReporter: {
      showDiff: true,
      output: 'minimal'
    },

    // Continuous Integration mode
    // if true, Karma captures browsers, runs the tests and exits
    singleRun: !watchMode,
    browserDisconnectTimeout: 10000, // default 2000
    browserDisconnectTolerance: 1, // default 0
    browserNoActivityTimeout: 4 * 60 * 1000, // default 10000

require('karma-jasmine-html-reporter'),
      require('karma-coverage-istanbul-reporter'),
      require('@angular-devkit/build-angular/plugins/karma')
    ],
    client: {
      clearContext: false // leave Jasmine Spec Runner output visible in browser
    },
    coverageIstanbulReporter: {
      dir: join(__dirname, '../../coverage'),
      reports: ['html', 'lcovonly'],
      fixWebpackSourcePaths: true
    },
    reporters: ['progress', 'kjhtml'],
    port: 9876,
    colors: true,
    logLevel: constants.LOG_INFO,
    autoWatch: true,
    browsers: ['Chrome'],
    singleRun: true
  };
};

require('karma-jasmine-html-reporter'),
      require('karma-coverage-istanbul-reporter'),
      require('@angular-devkit/build-angular/plugins/karma')
    ],
    client: {
      clearContext: false // leave Jasmine Spec Runner output visible in browser
    },
    coverageIstanbulReporter: {
      dir: join(__dirname, '../../coverage'),
      reports: ['html', 'lcovonly'],
      fixWebpackSourcePaths: true
    },
    reporters: ['progress', 'kjhtml'],
    port: 9876,
    colors: true,
    logLevel: constants.LOG_INFO,
    autoWatch: true,
    browsers: ['Chrome'],
    singleRun: false,
    captureTimeout: 180000,
    browserDisconnectTimeout: 180000,
    browserDisconnectTolerance: 3,
    browserNoActivityTimeout: 999999999,
    reportSlowerThan: 1000
  };
};

},
    customLaunchers: {
      Chrome_travis_ci: {
        base: 'Chrome',
        flags: [
          '--headless',
          '--disable-gpu',
          // Without a remote debugging port, Google Chrome exits immediately.
          '--remote-debugging-port=9222',
        ],
      },
    },
    browsers: process.env.TRAVIS ? ['Chrome_travis_ci'] : ['Chrome'],
    port: 9876,
    colors: true,
    logLevel: constants.LOG_INFO,
    autoWatch: true,
    singleRun: true,
  };
};

// available reporters: https://npmjs.org/browse/keyword/karma-reporter
    reporters: ['mocha'],
    mochaReporter: {
      showDiff: true,
      output: 'minimal'
    },

    // web server port
    port: 9876,

    // enable / disable colors in the output (reporters and logs)
    colors: true,

    // level of logging
    // possible values: config.LOG_DISABLE || config.LOG_ERROR || config.LOG_WARN || config.LOG_INFO || config.LOG_DEBUG
    logLevel: karmaConstants.LOG_INFO,

    // enable / disable watching file and executing tests whenever any file changes
    autoWatch: true,

    // start these browsers
    // available browser launchers: https://npmjs.org/browse/keyword/karma-launcher
    browsers: ['ChromeHeadless'],

    // Continuous Integration mode
    // if true, Karma captures browsers, runs the tests and exits
    singleRun: !watchMode,

    // Concurrency level
    // how many browser should be started simultaneous
    concurrency: Infinity,
    browserDisconnectTimeout: 100000,

require('karma-coverage-istanbul-reporter'),
      require('@angular-devkit/build-angular/plugins/karma')
    ],
    preprocessors: { 'dist/libs/ngx-pub-sub/**/!(*spec).js': ['coverage'] },
    client: {
      clearContext: false // leave Jasmine Spec Runner output visible in browser
    },
    coverageIstanbulReporter: {
      dir: join(__dirname, '../../coverage'),
      reports: ['html', 'lcovonly'],
      fixWebpackSourcePaths: true
    },
    reporters: ['progress', 'kjhtml'],
    port: 9876,
    colors: true,
    logLevel: constants.LOG_INFO,
    autoWatch: false,
    browsers: ['ChromeHeadless'],
    phantomjsLauncher: {
      // Have phantomjs exit if a ResourceError is encountered (useful if karma exits without killing phantom)
      exitOnResourceError: true
    },
    singleRun: true
  };
};

require('karma-jasmine-html-reporter'),
      require('karma-coverage-istanbul-reporter'),
      require('@angular-devkit/build-angular/plugins/karma'),
    ],
    client: {
      clearContext: false, // leave Jasmine Spec Runner output visible in browser
    },
    coverageIstanbulReporter: {
      dir: join(__dirname, '../../coverage'),
      reports: ['html', 'lcovonly'],
      fixWebpackSourcePaths: true,
    },
    reporters: ['progress', 'kjhtml'],
    port: 9876,
    colors: true,
    logLevel: constants.LOG_INFO,
    autoWatch: true,
    browsers: ['ChromeHeadless'],
    flags: ['--no-sandbox', '--disable-gpu', '--disable-web-security'],
    singleRun: true,
  }
}