Overview¶

What is Handcar?¶

Handcar is a web service that provides a restful JSON interface to the MC3 system’s learning objectives. To learn more about MC3, see the MC3 home page

Known issues/Issues under consideration for implementation in future releases¶

These items are known issues that are currently unsupported, but under consideration for implementation in future releases.

1. Free form querying using keywords to find objectives
2. Managing the configuration data for a bank directly via Handcar
3. Providing a metadata so the UI can dynamically validate data values
4. Support for the Assessment service
5. Managing assets directly via a separate repository service
6. Support for additional asset content types (mime types)
7. Storage of additional information such as name, description or extensions on Parent-Child relationships
8. Getting branding information about a bank or an asset
9. Cross bank relationships will not be blocked in all situations but are not fully supported as many details remain to be worked out

Other Related Documentation¶

Detailed documentation on all of the methods and data elements is contained in “Contract Docs” which fully explain the contract.

See http://mc3-demo.mit.edu/handcar/contractdocs/

Model Diagram¶

Model Description¶

Banks contain three main types of objects:

• Objectives– Learning Objectives which come in three distinct types:

  • Topics – also called concepts which define an area of knowledge , typically expressed as NOUNS
  • Outcomes – which are specific learning goals, typically expressed starting with VERBS
  • Generic Outcomes – which are outcomes that hold no real data themselves but simply tie together topics and content via a Bloom type – For example if the topic is “Derivative” a generic outcome could be “Learn Derivative”

• Activities which are tied to objectives - that a student may do in order to master the objective

• Assets which are tied to activities – that are typically the content that a student consumes as part of the activity

• In the model a single asset have multiple “Asset Contents” which may be different resolutions of the same asset, for example the same asset can have a thumbnail representation and full size JPG versions of the same picture.

• Relationships – Alternative View of Relationships between objectives, see The Relationship Service

Additionally there are configuration “types” and “grade scales” used to organize and categorize these three main objects.

For a detailed description of each of these objects and data fields see the Contract Documentation

Implementation Details¶

Handcar is a Java Servlet that uses Jersey to generate a RESTful API. It uses Moxy to serialize the objects into JSON.