LISTCAT JSON format - AWS Mainframe Modernization

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LISTCAT JSON format

The LISTCAT JSON format is defined by the following attributes:

  • optional "catalogId": identifier of the legacy catalog as a String, or "default" for the default catalog.

  • "identifier": the data set name, as a String.

  • "isIndexed": a boolean flag to indicate KSDS: true for KSDS, false otherwise.

  • "isLinear": a boolean flag to indicate ESDS: true for ESDS, false otherwise.

  • "isRelative": a boolean flag to indicate RRDS: true for RRDS, false otherwise

  • Note: "isIndexed", "isLinear", and "isRelative" are mutually exclusive.

  • "isFixedLengthRecord": a boolean flag: set to true if fixed length records data set, false otherwise.

  • "avgRecordSize": Average record size in bytes, expressed as a positive integer.

  • "maxRecordSize": Maximal Record size in bytes, expressed as an integer. Should be equal to avgRecordSize for fixed length record size.

  • for KSDS only: Mandatory primary Key definition (as nested object)

    • labelled "primaryKey"

    • "offset": 0-based bytes offset for the primary key in the record.

    • "length": length in bytes of the primary key.

    • "unique": must be set to true for primary key.

  • for KSDS/ESDS, collection of alternate keys (as collection of nested objects):

    • labelled "alternateKeys"

    • For each alternate key:

      • "offset": 0-based bytes offset for the alternate key in the record.

      • "length": length in bytes of the alternate key.

      • "unique": must be set to true for alternate key, if the key does not accept duplicate entries, false otherwise.

  • if no alternate keys are present, provide an empty collection:

    alternateKeys: []

The following is a sample KSDS LISTCAT JSON file.

{
  "catalogId": "default",
  "identifier": "AWS_M2_CARDDEMO_CARDXREF_VSAM_KSDS",
  "isIndexed": true,
  "isLinear": false,
  "isRelative": false,
  "isFixedLengthRecord": true,
  "avgRecordSize": 50,
  "maxRecordSize": 50,
  "primaryKey": {
    "offset": 0,
    "length": 16,
    "unique": true
  },
  "alternateKeys": [
    {
      "offset": 25,
      "length": 11,
      "unique": false
    }
  ]
}