Component ball_administration [Package ball]

Provide a suite of utility functions for logging administration. More...

Namespaces
namespace	ball

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Detailed Description

Outline

• Purpose
• Classes
• Description
  • Usage
    • Example 1: Managing Categories

Purpose:

Provide a suite of utility functions for logging administration.

Classes:

ball::Administration

namespace for logging administration utilities

See also:

Component ball_loggermanager

Description:

This component provides a namespace, ball::Administration, containing a suite of utility functions to facilitate administration of the ball logging subsystem from a console operator's perspective. Utilities are provided for adding a category to the registry maintained by the singleton instance of ball::LoggerManager (hereafter the "logger manager"), for setting the threshold levels of one or more categories, for setting a limit on the maximum number of categories allowed, and for retrieving the threshold levels of (established) categories. Note that a precondition of all of the utility functions is that the logger manager singleton must be initialized and not in the process of being shut down.

Usage:

This section illustrates intended use of this component.

Example 1: Managing Categories:

The code fragments in this example demonstrate several administration utilities that are used to create categories, and to set and access their threshold levels.

First we initialize the logger manager (for the purposes of this example, we use a minimal configuration):

  ball::LoggerManagerConfiguration lmConfig;
  ball::LoggerManagerScopedGuard   lmGuard(lmConfig);

Next define some hypothetical category names:

  const char *equityCategories[] = {
      "EQUITY.MARKET.NYSE",
      "EQUITY.MARKET.NASDAQ",
      "EQUITY.GRAPHICS.MATH.FACTORIAL",
      "EQUITY.GRAPHICS.MATH.ACKERMANN"
  };
  const int NUM_CATEGORIES = sizeof equityCategories
                           / sizeof equityCategories[0];

Category naming is by convention only. In this example, we have chosen a hierarchical naming convention that uses . to separate the constituents of category names.

In the following, the addCategory method is used to define a category for each of the category names in equityCategories. The threshold levels for each of the categories are set to slightly different values to help distinguish them when they are printed later. The addCategory method returns the address of the new category:

  for (int i = 0; i < NUM_CATEGORIES; ++i) {
      int retValue = ball::Administration::addCategory(
                                                equityCategories[i],
                                                ball::Severity::e_TRACE + i,
                                                ball::Severity::e_WARN  + i,
                                                ball::Severity::e_ERROR + i,
                                                ball::Severity::e_FATAL + i);
      assert(0 == retValue);  // added new category
  }

In the following, each of the new categories is accessed from the registry and its name and threshold levels are printed to bsl::cout:

  for (int i = 0; i < NUM_CATEGORIES; ++i) {
      const char* name    = equityCategories[i];
      int recordLevel     = ball::Administration::recordLevel(name);
      int passLevel       = ball::Administration::passLevel(name);
      int triggerLevel    = ball::Administration::triggerLevel(name);
      int triggerAllLevel = ball::Administration::triggerAllLevel(name);

      using namespace bsl;
      cout << "Category name: "       << name            << endl;
      cout << "\tRecord level:      " << recordLevel     << endl;
      cout << "\tPass level:        " << passLevel       << endl;
      cout << "\tTrigger level:     " << triggerLevel    << endl;
      cout << "\tTrigger-all level: " << triggerAllLevel << endl;
  }

The following is printed to stdout:

  Category name: EQUITY.MARKET.NYSE
          Record level:      192
          Pass level:        96
          Trigger level:     64
          Trigger-all level: 32

  Category name: EQUITY.MARKET.NASDAQ
          Record level:      193
          Pass level:        97
          Trigger level:     65
          Trigger-all level: 33

  Category name: EQUITY.GRAPHICS.MATH.FACTORIAL
          Record level:      194
          Pass level:        98
          Trigger level:     66
          Trigger-all level: 34

  Category name: EQUITY.GRAPHICS.MATH.ACKERMANN
          Record level:      195
          Pass level:        99
          Trigger level:     67
          Trigger-all level: 35

The following is similar to the first for-loop above, but this time the setThresholdLevels method is used to modify the threshold levels of existing categories. The setThresholdLevels method returns 1 in each case indicating the number of existing categories that were affected by the call:

  for (int i = 0; i < NUM_CATEGORIES; ++i) {
      const int returnValue = ball::Administration::setThresholdLevels(
                                                equityCategories[i],
                                                ball::Severity::e_TRACE - i,
                                                ball::Severity::e_WARN  - i,
                                                ball::Severity::e_ERROR - i,
                                                ball::Severity::e_FATAL - i);
      assert(1 == returnValue);  // modified one category
  }

When the NUM_CATEGORIES categories are accessed from the registry a second time and printed, the following is output to stdout showing the new threshold levels of the categories:

  Category name: EQUITY.MARKET.NYSE
          Record level:      192
          Pass level:        96
          Trigger level:     64
          Trigger-all level: 32

  Category name: EQUITY.MARKET.NASDAQ
          Record level:      191
          Pass level:        95
          Trigger level:     63
          Trigger-all level: 31

  Category name: EQUITY.GRAPHICS.MATH.FACTORIAL
          Record level:      190
          Pass level:        94
          Trigger level:     62
          Trigger-all level: 30

  Category name: EQUITY.GRAPHICS.MATH.ACKERMANN
          Record level:      189
          Pass level:        93
          Trigger level:     61
          Trigger-all level: 29

Finally, the category registry is closed to further additions by setting its maximum capacity to (the original) NUM_CATEGORIES:

  ball::Administration::setMaxNumCategories(NUM_CATEGORIES);

Following this call to setMaxNumCategories, subsequent calls to addCategory will fail (until such time as setMaxNumCategories is called again with an argument value that is either 0 or is greater than NUM_CATEGORIES, where 0 indicates the category registry has unlimited capacity).