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Referenced Attestation

Unlocking the full potential of composability in BAS attestations, the refUID feature allows seamless referencing between attestations, establishing a hierarchy or chain of interdependent attestations. This organized structure fosters a clearer understanding of the relationships between attestations.


Incorporating refUID involves one attestation referencing another by utilizing its unique identifier (UID) as the refUID field in the new attestation. This establishes a relationship where the referenced attestation acts as a foundation or prerequisite for the new one, indicating dependencies between attestations. As a practical example, when posting on social media, your main attestation is the post UID, others can attest by liking or sharing, referencing the original UID in their new attestation.

Examples of Referenced Attestations Usage

  1. Chain of Record: In real estate, track title transfers by linking attestations of previous and current owners.
  2. Comprehensive View: Create a structured data view, where one attestation provides broader context to information in another, e.g., Comprehensive Digital Identities.
  3. Approval Systems: Track multiple party approvals by using referenced attestations, each referencing the original proposal attestation.
  4. Disputes: Indicate disagreements by creating a new attestation referencing the original in case of disputes.
  5. Version Control: Update or revise attestation data, creating a clear history by referencing the previous version.

Creating a Referenced Attestation

To reference an attestation, include its UID in the refUID field of the new attestation. BAS validates existence of the refUID, ensuring the new attestation references the specified attestation.

Referencing Multiple Attestations

For multiple references in a single attestation, use a schema with a bytes32 field as an array, accepting an array of `UIDs`` for the previous attestations you wish to reference. By passing an array of UIDs as the value, you can now efficiently reference multiple attestations in a single new attestation.