Query Language

The Verifier’s query language defines precise requirements for acceptable credentials. By specifying fields and applying JSON Schema filters, you ensure that only credentials meeting exact criteria are accepted.

Key Concepts

• Paths: Identify data fields in a credential’s JSON structure using JSONPath syntax.

• Filters: Apply JSON Schema rules (e.g., type, enum, pattern) to validate content at the specified path.

Example

Proof of Purchase Credential Requirement:

• type includes "ProofOfPurchase".

• credentialSubject.id matches the pattern ^did:empe:.*$.

[
  {
    "fields": [
      {
        "path": ["$.type"],
        "filter": {
          "type": "array",
          "contains": {"const": "ProofOfPurchase"}
        }
      },
      {
        "path": ["$.credentialSubject.id"],
        "filter": {
          "type": "string",
          "pattern": "^did:empe:.*$"
        }
      }
    ]
  }
]

By combining paths and filters, the Verifier ensures that only credentials meeting your defined requirements pass the verification process.