1.6. The Auditor RESTful JSON API¶

The API specified here follows the general conventions for all details not specified in the individual requests. The glossary defines all specific terms used in this section.

1.6.1. Authentication ¶

Each auditor instance has separate authentication settings for the private API resources of that instance.

Currently, the API supports two main authentication methods:

external: With this method, no checks are done by the auditor backend. Instead, a reverse proxy / API gateway must do all authentication/authorization checks.
token: With this method, the client must provide a Authorization: Bearer $TOKEN header, where $TOKEN is a secret authentication token configured for the instance which must begin with the RFC 8959 prefix.

1.6.2. Obtaining Auditor Version ¶

This API is used by merchants to obtain a list of all exchanges audited by this auditor. This may be required for the merchant to perform the required know-your-customer (KYC) registration before issuing contracts.

GET /config¶

Get the protocol version and some meta data about the auditor. This specification corresponds to current protocol being version 1.

Response:

200 OK:: The auditor responds with an AuditorVersion object. This request should virtually always be successful.

Details:

interface AuditorVersion {
  // libtool-style representation of the Taler protocol version, see
  // https://www.gnu.org/software/libtool/manual/html_node/Versioning.html#Versioning
  // The format is "current:revision:age".  Note that the auditor
  // protocol is versioned independently of the exchange's protocol.
  version: string;

  // URN of the implementation (needed to interpret 'revision' in version).
  // @since v0, may become mandatory in the future.
  implementation?: string;

  // Return which currency this auditor is auditing for.
  currency: string;

  // EdDSA master public key of the auditor.
  auditor_public_key: EddsaPublicKey;

  // EdDSA master public key of the exchange.
  // Added in protocol v1.
  exchange_master_public_key: EddsaPublicKey;
}

Note

This API is still experimental (and is not yet implemented at the time of this writing).

1.6.3. Obtaining Exchange Signing Keys List ¶

This API is used by auditor to obtain a list of all exchanges signing keys to be audited.

GET /exchange-sign-keys¶

Get a list of all exchange signing keys to be audited by the auditor.

Response:

200 OK:: The auditor responds with a ExchangeSignKeysList object. This request should virtually always be successful.

Details:

interface ExchangeSignKeysList {
  // Exchange signing keys to be audited by the auditor.
  exchange-sign-key: ExchangeSignKeyEntry[];
}

interface ExchangeSignKeyEntry {

  // Public online signing key of the exchange.
  exchange_pub: EddsaPublicKey;

  // Base URL of the exchange.
  master_sig: EddsaSignature;

  // Time when online signing key will first be use.
  ep_valid_from: Timestamp;

  // Time when this online signing key will no longer be used.
  ep_expire_sign: Timestamp;

  // Time when this online signing key legally expires.
  ep_expire_legal: Timestamp;
}

Note

This API is still experimental (and is not yet implemented at the time of this writing).

1.6.4. Deposit Confirmations ¶

Merchants should probabilistically submit some of the deposit confirmations they receive from the exchange to auditors to ensure that the exchange does not lie about recording deposit confirmations with the exchange. Participating in this scheme ensures that in case an exchange runs into financial trouble to pay its obligations, the merchants that did participate in detecting the bad behavior can be paid out first.

PUT /deposit-confirmation¶

Submits a DepositConfirmation to the exchange. Should succeed unless the signature provided is invalid or the exchange is not audited by this auditor.

Response:

200 Ok:: The auditor responds with a DepositAudited object. This request should virtually always be successful.
403 Forbidden:: The signature on the deposit confirmation is invalid.
410 Gone:: The public key used to sign the deposit confirmation was revoked.

Details:

interface DepositAudited {
  // TODO: maybe change to 204 No content instead?
}

interface DepositConfirmation {

  // Hash over the contract for which this deposit is made.
  h_contract_terms: HashCode;

  // Hash over the extensions.
  h_extensions: HashCode;

  // Hash over the wiring information of the merchant.
  h_wire: HashCode;

  // Time when the deposit confirmation confirmation was generated.
  timestamp: Timestamp;

  // How much time does the merchant have to issue a refund
  // request?  Zero if refunds are not allowed.
  refund_deadline: Timestamp;

  // By what time does the exchange have to wire the funds?
  wire_deadline: Timestamp;

  // Amount to be deposited, excluding fee.  Calculated from the
  // amount with fee and the fee from the deposit request.
  amount_without_fee: Amount;

  // Array of public keys of the deposited coins.
  coin_pubs: EddsaPublicKey[];

  // Array of deposit signatures of the deposited coins.
  // Must have the same length as coin_pubs.
  coin_sigs: EddsaSignature[];

  // The Merchant's public key.  Allows the merchant to later refund
  // the transaction or to inquire about the wire transfer identifier.
  merchant_pub: EddsaPublicKey;

  // Signature from the exchange of type
  // TALER_SIGNATURE_EXCHANGE_CONFIRM_DEPOSIT.
  exchange_sig: EddsaSignature;

  // Public signing key from the exchange matching exchange_sig.
  exchange_pub: EddsaPublicKey;

  // Master public key of the exchange corresponding to master_sig.
  // Identifies the exchange this is about.
  // @deprecated since v1 (now ignored, global per auditor)
  master_pub: EddsaPublicKey;

  // When does the validity of the exchange_pub end?
  ep_start: Timestamp;

  // When will the exchange stop using the signing key?
  ep_expire: Timestamp;

  // When does the validity of the exchange_pub end?
  ep_end: Timestamp;

  // Exchange master signature over exchange_sig.
  master_sig: EddsaSignature;
}

Note

This API is still experimental (and is not yet implemented at the time of this writing). A key open question is whether the auditor should sign the response information.

This API is used by the auditor to obtain a list of all deposit confirmations that the auditor did not receive by the exchange, only by the merchant.

GET /deposit-confirmation¶

Get a list of all deposit confirmations that were not received by the auditor from the exchange to be manually audited.

Response:

200 OK:: The auditor responds with a DepositConfirmationList object.
204 No Content:: No missing deposit confirmations found.

Details:

interface DepositConfirmationList {
  // Deposit confirmations to be audited.
  deposit-confirmations: DepositConfirmation[];
}

interface DepositConfirmation {

  // Database row id of entry
  row_id: Integer;

  // Time when the deposit confirmation confirmation was generated.
  timestamp: Timestamp;

  // How much time does the merchant have to issue a refund
  // request?  Zero if refunds are not allowed.
  refund_deadline: Timestamp;

  // By what time does the exchange have to wire the funds?
  wire_deadline: Timestamp;

  // Amount to be deposited, excluding fee.  Calculated from the
  // amount with fee and the fee from the deposit request.
  amount_without_fee: Amount;
}

Note

This API is still experimental (and is not yet implemented at the time of this writing).

This API is used by the auditor to delete an audited deposit confirmation.

DELETE /deposit-confirmation/$SERIAL_ID¶

Delete deposit confirmation entry with given serial_id.

Response:

204 No content:: The deposit confirmation was deleted.
401 Unauthorized:: Unauthorized request.
404 Not found:: The deposit confirmation was unknown.

Note

This API is still experimental (and is not yet implemented at the time of this writing).

1.6.5. Obtaining list of auditor balances ¶

This API is used to obtain a list of all the balances that are stored by the auditor.

GET /balances¶

Get a list of all balances stored by the auditor.

Response:

200 OK:: The auditor responds with a BalanceList object.
409 Conflict:: Balance missing or other error occured.

Details:

interface BalanceList {
  // Total amount reported
  auditor_total_reported_balance: Amount;

  // Amount potentially missing
  auditor_missing_balance: Amount;

  //...
}

Note

This API is still experimental (and is not yet implemented at the time of this writing). The API will be further developed as needed.

1.6.6. Obtaining list of pending denominations ¶

This API is used by the auditor to obtain a list of pending denominations

GET /pending-denominations¶

Get a list of all pending denominations.

Response:

200 OK:: The auditor responds with a PendingDenominationList object.
204 No content:: No pending demoninations found.

Details:

interface PendingDenominationList {
  // PendingDenominationList of the auditor.
  pending_denomination: PendingDenomination[];
}

interface PendingDenomination {

  // Balance of denomination.
  denom_balance: Amount;

  // Amount that was lost due to failures by the exchange.
  denom_loss: Amount;

  // Amount at risk of loss due to recoup operations.
  denom_risk: Amount;

  // Amount actually lost due to recoup operations after a revocation.
  recoup_loss: Amount;
}

Note

This API is still experimental (and is not yet implemented at the time of this writing).

1.6.7. Complaints ¶

This API is used by the wallet or merchants to submit proof of misbehavior of an exchange to the auditor.

Note

To be designed and implemented.

PUT /complain¶

Complain about misbehavior to the auditor.

1.5. Wallet-Core API Documentation

1.7. Backup and Synchronization RESTful API

GNU Taler

1.6. The Auditor RESTful JSON API¶

1.6.1. Authentication¶

1.6.2. Obtaining Auditor Version¶

1.6.3. Obtaining Exchange Signing Keys List¶

1.6.4. Deposit Confirmations¶

1.6.5. Obtaining list of auditor balances¶

1.6.6. Obtaining list of pending denominations¶

1.6.7. Complaints¶

1.6.1. Authentication ¶

1.6.2. Obtaining Auditor Version ¶

1.6.3. Obtaining Exchange Signing Keys List ¶

1.6.4. Deposit Confirmations ¶

1.6.5. Obtaining list of auditor balances ¶

1.6.6. Obtaining list of pending denominations ¶

1.6.7. Complaints ¶