Metadata integration to eduOER Repository.

In order a metadata provider to be part of the eduOER Repository he should take the following steps:

Step 1. Fill the form

eduOER Repository Questionnaire

Step 2. Expose only metadata

Since the eduOER Repository is a metadata repository(i.e refaratory) the potential providers should expose their metadata not the actual content.

Step 3. Know your metadata

eduOER metadata aggregation ecosystem offers the metadata analytics service.The metadata analytics service is a web application that offers a deeper insight of the metadata content based on statistics.This service is intended to be used by potential metadata providers who want to gain a deeper knowledge of their metadata, mine bad metadata curation practices and get a more descriptive picture of their metadata (how specific elements are used etc). The users after uploading their metadata and configuring the specific statistical experiment can get the results either as CSV files or as visualizations directly created from the web application.For more information regarding the statistical measures and how it works refer to the Metadata Analytics Web Application FAQ page.

Step 4. Metadata exposure through OAI-PMH or RSS protocols

The eduOER Metadata Aggregation engine harvests metadata using OAI-PMH or RSS protocols.Thus a metadata provider should implement these protocols.

Regarding OAI-PMH protocol the metadata schema which the metadata will utilize can be anything that fits your needs a standard, a custom or the eduOER Application Profile(based on IEEE LOM)

The eduOER Aggregation ecosystem includes OAI-PMH target service.The OAI-PMH target service offers the ability to a potential metadata provider expose its metadata using OAI-PMH protocol instead of having to set its own.The newly added metadata are exposed as a new OAI-PMH set to potential metadata harvesters.

For more info related to OAI-PMH protocol and implementations visit this link.

For more info related to RSS protocol visit this link. The current RSS schemas supported are the following:

  • Standard RSS elements.
  • itunes
  • itunesu

Refer to the eduOER aggregation possible issues page to check the possible issues that may arise during metadata aggregation(harvesting section).

Step 5. Metadata validation

The eduOER Metadata Aggregation ecosystem also includes the Metadata Validation service which is implemented by Ariadne foundation and could be used for providing validation of metadata instances against predefined application profiles, for example based on IEEE LOM. To ensure that only compliant metadata are stored in the eduOER Metadata Repository, we use the validation service to check both the syntactic and semantic validity of the instances against the used profiles. The validation service has a modular approach, and combines different sorts of validation techniques including:

  • XSD schema, mainly used for structural validation of xml metadata.
  • Schematron rules, which are very flexible and are used for:
    • Verifying the presence of mandatory elements.
    • Checking the presence of empty attribute fields. For example, in the langstring datatype of LOM, the language of a string should be recorded in a non-empty attribute “language”.
    • Enforcing inter-field dependencies, like conditional fields.
  • Checking for the correct use of the allowed terms in a vocabulary.
  • Validation of vcards present in the metadata with a separate vcard parser or validator.

The validation service could be used for validation of one or more metadata records.Also it could be used for full OAI-PMH target validation in case this target follows a specific available to the validation service application profile.

Refer to the eduOER aggregation possible issues page to check the possible issues that may arise during metadata aggregation(validation section).

Step 6. Help on the metadata transformation process

In case the exposed metadata utilize a custom metadata application profile and to ensure that only compliant metadata are stored in the eduOER Metadata Repository a metadata transformation process is performed during metadata aggregation. The metadata transformation process accepts as input an XSLT mapping file which contains the mapping rules.

With the Mint mapping tool you can define semantic mappings between the source and target schemas. An XSLT is then generated, based on these mappings, that can automatically convert all imported items.For more info on Mint Mapping tool refer to the respective wiki.

Step 7.Check the aggregation progress and results

When eduOER Metadata aggregation process starts one can use the eduOER Metadata aggregation dashboard to get an idea of the results at the various aggregation steps and find out issues.

Step 8. Check metadata statistics after aggregation

Additionally to metadata aggregation results dashboard a metadata statistical analysis dashboard offers a deeper insight at the aggregated metadata(the ones that were not filtered out during various metadata aggregation steps).

Refer to the eduOER aggregation possible issues page to check the possible issues that may arise during metadata aggregation.