Show Source Feature

Overview

The show_source attribute allows the raw XML source of an exercise (or part of it) to be displayed instead of the rendered exercise.

This feature is primarily intended for:

  • Users learning how to create exercises in OpenTA

  • Course participants in “how to use OpenTA” courses

  • Authors who want to inspect XML structure directly

When activated, the raw XML is displayed in addition to the rendered content.

Activation Requirements

The show_source attribute works only if:

  1. It is present in the XML, and

  2. The corresponding course setting that enables “Show Source” is activated.

If the course setting is disabled, the attribute is silently ignored.

This allows the attribute to remain in exercise files without affecting production courses.

User Guide

Where It Can Be Placed

The show_source attribute may be placed on any first-level block:

  • <exercise>

  • <global>

  • <question>

Scope Rules

The scope depends entirely on placement.

  1. On <exercise>

    …

    Effect:

    • Displays the raw XML of the entire exercise

    • All inner show_source attributes are ignored

    • No rendering occurs anywhere in the exercise

  2. On <global>

    …

    Effect:

    • Displays only the raw XML of the <global> block

    • Other parts of the exercise render normally

    • Overridden if <exercise> has show_source

  3. On <question>

    …

    Effect:

    • Displays only the raw XML of that specific question

    • Other questions render normally

    • Overridden if <exercise> has show_source

Precedence Rules

If show_source appears in multiple places:

  1. The outermost placement takes priority.

  2. Inner placements are ignored.

Hierarchy:

exercise > global > question

What Is Displayed

When activated, the following is shown:

  • Raw XML exactly as written

  • No LaTeX processing

  • No MathJax rendering

  • No HTML interpretation

This allows users to study:

  • Structure

  • Attributes

  • Expressions

  • Hints

  • Validation patterns

Best Practices

  • Enable this feature only in instructional or development courses.

  • Avoid using it in production assessment courses.

  • Use exercise-level placement when documenting complete structure.

  • Use question-level placement when demonstrating specific constructs.

Developer Reference

Attribute Behavior

  • Attribute name: show_source

  • Expected value: "true"

  • Default behavior: If absent, no source is shown.

If the attribute appears at multiple levels, only the outermost first-level block is activated.

Rendering Logic

When show_source is active for a given scope:

  • Rendering of that scope is suppressed.

  • The raw XML string for that scope is returned.

  • Inner show_source attributes are ignored if overridden by an outer scope.

Security Considerations

  • The attribute is gated by a course-level configuration setting.

  • If the course setting is disabled, the attribute is ignored.

  • This prevents accidental exposure in production environments.

Intended Use Cases

  • Teaching XML structure in OpenTA

  • Debugging exercise structure

  • Documentation and review

  • Demonstration courses

Example: Full Exercise

a = 5 a + 3

In this case, the full raw XML is displayed instead of rendered output.