Proof of Transfer

Integrating Proof of Transfer capability into a Canton Network Explorer gives users a seamless interface to verify transaction statuses natively, while preserving privacy.

Integration Blueprint

To provide a seamless customer journey, the Explorer handles incoming payload information—an UpdateID and a Transfer Object payload—usually supplied via direct user copy-pasting or automated routing via a platform referral URL parameter. The platform then submits this data payload to the DA Registry API to render an indisputable confirmation receipt.

Step-by-Step Implementation Flow

Follow this workflow sequence to build the verification stack inside your network explorer ecosystem.

1. Configure the Target Inbound Route

Create a dedicated, public route in your application routing profile (e.g., /verify-transfer) designated to handle incoming cryptographic verification payloads. Ensure the handler is equipped to extract query string components seamlessly if redirected from external wallet histories.

2. Construct the Payload Input Form Interface

Design a clean input card component. If parameters are present in the URL path, auto-populate the data fields for the user. If blank, provide a structured text area box allowing the user to paste their raw transaction JSON payload manually.

3. Query the DA Registry Endpoint

Dispatch an asynchronous network request from your application frontend layer directly to the live DA Registry network service infrastructure node using the structured body schemas.

Curl Request Signature

curl -X POST "[https://api.utilities.digitalasset.com/api/utilities/v0/registry/transfer/v0/proof](https://api.utilities.digitalasset.com/api/utilities/v0/registry/transfer/v0/proof)" \
  -H "Content-Type: application/json" \
  -d '{
    "updateId": "1220b1223907e943aa24b52e874a78c86067bafcdb429958994cbd2b33fc41df5e1a",
    "transfer": {
      "sender": "issuer::12204b6be4677e1e110e63cb3dcd89c62025932458547a09e580458e29e822e9ee26",
      "receiver": "holder::12204b6be4677e1e110e63cb3dcd89c62025932458547a09e580458e29e822e9ee26",
      "amount": "1.0000000000",
      "instrumentId": {
        "admin": "registrar::12204b6be4677e1e110e63cb3dcd89c62025932458547a09e580458e29e822e9ee26",
        "id": "INST"
      },
      "requestedAt": "2025-12-09T13:29:42.6187Z",
      "executeBefore": "2025-12-12T13:28:53.7492Z",
      "inputHoldingCids": [
        "0020a2a23208de8d9fec1efd1c377d9a4343eac83f27b26b554f1c9e95c9653c05ca12122056c38daac3b523885fe8436215c72d0181e81e34379918246fc0ef75852990f9"
      ]
    }
  }'

4. Parse Outcomes & Render Visual Verification Status

Read the structured enum value returned from the API service. Update the client view container to reflect the deterministic ledger evaluation output cleanly using descriptive status layouts.

API Request Schema Specifications

Your interface layer must accurately frame the request body definitions before transmitting data packages to the network node validation server.

Technical Payload Fields

updateId

string

required

The unique cryptographic ledger hash tracking indicator marking the target execution sequence window.

transfer

object

required

The private core transaction details package required to process cryptographic balance sheet verification.

Show Properties Block

sender

string

required

The specific identity fingerprint address origin string dispatching the digital asset.

receiver

string

required

The destination identity fingerprint address authorized to take legal custody of the asset.

amount

string

required

Alphanumeric decimal string specifying the absolute transfer token unit volume.

instrumentId

object

required

Identifies the core registry blueprint details governing the tokenized asset.

requestedAt

string (date-time)

required

ISO-8601 string mapping the exact timestamp historical moment the transfer workflow initialization sequence fired.

executeBefore

string (date-time)

required

The drop-dead expiration constraint timeline timestamp bounding the transaction validity lifecycle on-chain.

inputHoldingCids

array of strings

required

The explicit array of structural tracking contract identifiers used directly to fund the ledger movement.

UI Component States & Response Handling

To ensure alignment with network expectations, map the direct string responses from the DA Registry API into intuitive, color-coded dashboard indicators for your end users.

Success Resolution
Pending Evaluation
Failure Response
Validation Error Handling

Rendering UI Target: Balanced Verification Badge

The transaction variables are authenticated against the ledger state and indicate successful contract finalization.

Response Sample

{
  "status": "Success"
}

Interface Suggestion: Render a prominent checkmark module highlighting an “Indisputably Settled” receipt statement. Users can confidently treat this transaction as settled.

Rendering UI Target: Progress Indicator Badge

The parameters represent a structurally valid ledger entry path, but the contract steps are still moving through live execution queues.

Response Sample

{
  "status": "Pending"
}

Interface Suggestion: Inform users that the asset transfer is in an intermediate lifecycle phase (e.g., a two-step transfer workflow where the destination party hasn’t formally accepted an open offer yet). Advise re-evaluating once final settlement commits.

Rendering UI Target: Terminated Execution Badge

The proof data successfully resolved to a historical ledger event path, but the workflow instructions failed execution or were rejected.

Response Sample

{
  "status": "Failure"
}

Interface Suggestion: Update the dashboard to inform the user that the transaction request was intentionally canceled, explicitly aborted by a counterparty, or simply expired on-chain.

Rendering UI Target: Input Mismatch Panel (HTTP 400)

The input fields failed lookup, are missing parameters, or contain structured mismatches against live on-chain transactional tracking parameters.

Response Sample

{
  "error": "invalid_request",
  "error_description": "Something went wrong"
}

Data Privacy Guardrail Rule: The backend deliberately zero-discloses tracking details to prevent unwanted transaction state farming by unauthorized actors. Ensure your Explorer frontend handles errors elegantly with a general “Invalid Proof Credentials” module rather than displaying custom data logs.

​Integration Blueprint

​Step-by-Step Implementation Flow

​API Request Schema Specifications

​Technical Payload Fields

​UI Component States & Response Handling

​Rendering UI Target: Balanced Verification Badge

​Rendering UI Target: Progress Indicator Badge

​Rendering UI Target: Terminated Execution Badge

​Rendering UI Target: Input Mismatch Panel (HTTP 400)

Integration Blueprint

Step-by-Step Implementation Flow

API Request Schema Specifications

Technical Payload Fields

UI Component States & Response Handling

Rendering UI Target: Balanced Verification Badge

Rendering UI Target: Progress Indicator Badge

Rendering UI Target: Terminated Execution Badge

Rendering UI Target: Input Mismatch Panel (HTTP 400)