Certificate data model

The Certificate struct is the same logical record whether you read it onchain, send it in JSON to the HTTP API, or encode it as a tuple for mint_certificate.

Field reference

Field	Onchain type	Description
registration_date	uint256	Unix timestamp of registration
delivery_correlative	String[10]	Short delivery / batch identifier
participant_names	String[100]	Participant first name(s)
participant_last_names	String[100]	Participant last name(s)
course_name	String[100]	Course title
hours_number	uint256	Total course hours
sessions_number	uint256	Number of sessions
issuing_institution	String[100]	Issuing institution name
image_url	String[256]	Image URL for metadata
certificate_url	String[256]	PDF or landing page for the credential

JSON (HTTP API)

Request bodies use snake_case keys. Numeric fields may be sent as integers or decimal strings; responses return registration_date, hours_number, and sessions_number as decimal strings for JSON safety.

See Certificate metadata fields in the API reference.

Onchain tuple order

When encoding data_ for mint_certificate, use the table order top to bottom (matches ABI tuple ordering).

Python-style example

factory.mint_certificate(
    certificate_address,
    (
        1734567890,
        "DLV-001",
        "John",
        "Doe",
        "EBG Course",
        40,
        10,
        "EBG Academy",
        "https://example.com/img.png",
        "https://example.com/cert.pdf",
    ),
    recipient_address,
)

Collection deployment strings

Factory create_certificate uses separate limits:

Argument	Max length (chars)
name_	25
symbol_	5
base_uri_	80

Choose base_uri_ so tokenURI aligns with your metadata host (see NFT metadata).