Understanding the EDI Schema Language

X12 EDI Connector uses a YAML format called EDI Schema Language (ESL) to represent EDI schemas. Basic ESLs define the structure of Electronic Data Interchange (EDI) messages in terms of:

  • structures, known as transaction sets in X12 terminology

  • groups, known as loops, in X12

  • segments, composites, and elements

ESLs for the all supported X12 versions are included. If you are using HIPAA, then a set of HIPAA variations of base X12 transaction sets are included.

You can customize X12 schema definitions to suit your data by defining an overlay schema. An overlay schema is a type of ESL that enables you to modify a base schema, such as an X12 4010 850 schema, with your specific conventions. You don’t need an overlay schema if you’re using the structure defined by the standard, but most EDI exchanges modify the base definitions in an implementation convention.

You can define your own schemas from scratch, or copy and edit a base X12 schema definition to suit your data as shown in the EDI Schema Language Reference.

Finding Schema Locations

To use the connector, you need to know the locations of the schemas in your project. If you’re using out-of-the-box X12 schemas and not customizing anything, the schema location follows the /x12/{version}/{transaction set}.esl convention.

For example, using the 005010 version and the 850 transaction set, the schema location is /x12/005010/850.esl.

If you’re using one or more custom schemas, refer to XML Schema and Trading Partner Configuration for complete information about setting your schema locations.