Autolab Features Documentation

This guide details the usage of features in Autolab.

Features Documented (Work in Progress):


Scoreboards are a central concept of Autolab and are created by the output of Autograders. They anonomously rank students submitted assignments inspiring health competition and desire to improve. They are simple and highly customizable. Scoreboard's can be added/edited on the edit assessment screen (/courses/<course>/assessments/<assessment>/edit).

Scoreboard Edit

In general, scoreboards are configured using a JSON string.

Default Scoreboard

The default scoreboard displays the total problem scores, followed by each individual problem score, sorted in descending order by the total score.

Custom Scoreboards

Autograded assignments have the option of creating custom scoreboards. You can specify your own custom scoreboard using a JSON column specification.

The column spec consists of a "scoreboard" object, which is an array of JSON objects, where each object describes a column.

Example: a scoreboard with one column, called Score.

    "scoreboard": [ 

A custom scoreboard sorts the first three columns, from left to right, in descending order. You can change the default sort order for a particular column by adding an optional "asc:1" element to its hash.

Example: Scoreboard with two columns, "Score" and "Ops", with "Score" sorted descending, and then "Ops" ascending:

    "scoreboard": [ 
        {"hdr":"Ops", "asc":1} 

Scoreboard Entries

The values for each row in a custom scoreboard come directly from a scoreboard array object in the autoresult string produced by the Tango, the autograder.

Example: Autoresult returning the score (97) for a single autograded problem called autograded, and a scoreboard entry with two columns: the autograded score (Score) and the number of operations (Ops):

    "scores": {
    "scoreboard":[97, 128] 

For more information on how to use Autograders and Scoreboards together, visit the Guide for Lab Authors.

Embedded Forms

This feature allows an instructor to create an assessment which does not require a file submission on the part of the student. Instead, when an assessment is created, the hand-in page for that assessment will display an HTML form of the instructor’s design. When the student submits the form, the information is sent directly in JSON format to the Tango grading server for evaluation.

Tango Required

Tango is needed to use this feature. Please install Tango and connect it to Autolab before proceeding.

Embedded Form

Creating an Embedded Form

Create an HTML file with a combination of the following elements. The HTML file need only include form elements, because it will automatically be wrapped in a <form></form> block when it is rendered on the page.

In order for the JSON string (the information passed to the grader) to be constructed properly, your form elements must follow the following conventions:

  • A unique name attribute
  • A value attribute which corresponds to the correct answer to the question (unless it is a text field or text area)

HTML Form Reference:

Text Field (For short responses)

<input type=“text” name=“question-1”/>

Text Area (For coding questions)

<textarea name=“question-2” style=“width:100%”/>

Radio Button (For multiple choice)

<div class = “row>
    <input name=“question-3” type=“radio” value=“object” id=“q3-1”/>
    <label for="q3-1">Object</label>
    <input name=“question-3” type=“radio” value=“boolean” id=“q3-2”/>
    <label for=“q3-2”>Boolean</label>

Dropdown (For multiple choice or select all that apply)

<select multiple name="question-4">
    <option value="1">Option 1</option>
    <option value="2">Option 2</option>
    <option value="3">Option 3</option>

Example Form (shown in screenshot above)

<input type="text" name="question-1" id="q1" placeholder="What's your name?" />

<div class = "row">
    <input name="question-2" type="radio" value="freshman" id="q3-1"/>
    <label for="q3-1">Freshman</label>

    <input name="question-2" type="radio" value="sophomore" id="q3-2"/>
    <label for="q3-2">Sophomore</label>

    <input name="question-2" type="radio" value="junior" id="q3-3"/>
    <label for="q3-3">Junior</label>

    <input name="question-2" type="radio" value="senior" id="q3-4"/>
    <label for="q3-4">Senior</label>
<label for="q4">What's your favorite language?</label>
<select name="question-3" id="q4">
    <option value="C">C</option>
    <option value="Python">Python</option>
    <option value="Java">Java</option>

Navigate to the Basic section of editing an assessment (/courses/<course>/assessments/<assessment>/edit), check the check box, and upload the HTML file. Ensure you submit the form by clicking Save at the bottom of the page.

Embedded Form Edit

Grading an Embedded Form

When a student submits a form, the form data is sent to Tango in the form of a JSON string in the file out.txt. In your grading script, parse the contents of out.txt as a JSON object. The JSON object will be a key-value pair data structure, so you can access the students response string (value) by its unique key (the name attribute).

For the example form shown above, the JSON object will be as follows:

    "question-1":"John Smith",

Use this information to do any processing you need in Tango.If you find any problems, please file an issue on the Autolab Github.