vspd/docs/api.md

API

General notes

• Success responses use HTTP status 200 and a JSON encoded body.

• Error responses use either HTTP status 500 or 400, and a JSON encoded error in the body, e.g. {"error":"Description"}.

• Requests which reference specific tickets need to be properly signed as described in two-way-accountability.md.

• Implementation of request and response types can be found in webapi/types.go.

Expected usage

Get VSP info

Clients should retrieve the VSP's public key so they can check the signature on future API responses. A VSP should never change their public key, so it can be requested once and cached indefinitely. vspclosed indicates that the VSP is not currently accepting new tickets. Calling /feeaddress when a VSP is closed will result in an error.

• GET /api/vspinfo

  No request body.

  Response:

  {
      "timestamp":1590599436,
      "pubkey":"SjAmrAqH7LScCUwM1qo5O6Cu7aKhrM1ORszgZwD7HmU=",
      "feepercentage":0.05,
      "vspclosed":false,
      "network":"testnet3"
  }
  

Register ticket

Registering a ticket is a two step process. The VSP will not add a ticket to its voting wallets unless both of these calls have succeeded.

Step One

Request fee amount and address for a ticket. The fee amount is only valid until the expiration time has passed. The fee amount is an absolute value measured in DCR.

• POST /feeaddress

  Request:

  {
      "timestamp":1590509066,
      "tickethash":"484a68f7148e55d05f0b64a29fe7b148572cb5272d1ce2438cf15466d347f4f4"
  }
  
  

  Response:

  {
      "timestamp":1590509066,
      "feeaddress":"Tsfkn6k9AoYgVZRV6ZzcgmuVSgCdJQt9JY2",
      "feeamount":0.001,
      "expiration":1590563759,
      "request": {"<Copy of request body>"}
  }
  

Step Two

Provide the voting key for the ticket, voting preference, and a signed transaction which pays the fee to the specified address. If the fee has expired, this call will return an error and the client will need to request a new fee by calling /feeaddress again.

The VSP will not broadcast the fee transaction until the ticket purchase has 6 confirmations. For this reason, it is important that the client ensures the output being spent in the transaction is not spent elsewhere.

The VSP will not add the ticket to its voting wallets until the fee transaction has 6 confirmations.

• POST /payfee

  Request:

  {
  "timestamp":1590509066,
  "tickethash":"484a68f7148e55d05f0b64a29fe7b148572cb5272d1ce2438cf15466d347f4f4",
  "feetx":"010000000125...737b266ffb9a93",
  "votingkey":"PtWUJWhSXsM9ztPkdtH8REe91z7uoidX8dsMChJUZ2spagm7YvrNm",
  "votechoices":{"headercommitments":"yes"}
  }
  

  Response:

  {
  "timestamp":1590509066,
  "request": {"<Copy of request body>"}
  }
  

Ticket Status

Clients can check the status of a ticket at any time after calling /feeaddress. The lifecycle of the ticket is represented with a set of boolean fields:

• ticketconfirmed is true when the ticket transaction has 6 confirmations.
• feetxreceived is true when the VSP has received a valid fee transaction.
• feetxbroadcast is true when the VSP has broadcast the fee transaction.
• feeconfirmed is true when the fee transaction has 6 confirmations.

The VSP will only add tickets to the voting wallets when all four of these conditions are met. feetxhash will only be populated if feetxbroadcast is true.

• GET /ticketstatus

  Request:

  {
      "timestamp":1590509066,
      "tickethash":"484a68f7148e55d05f0b64a29fe7b148572cb5272d1ce2438cf15466d347f4f4"
  }
  

  Response:

  {
    "timestamp":1590509066,
    "ticketconfirmed":true,
    "feetxreceived":true,
    "feetxbroadcast":true,
    "feeconfirmed":false,
    "feetxhash": "e1c02b04b5bbdae66cf8e3c88366c4918d458a2d27a26144df37f54a2bc956ac",
    "votechoices":{"headercommitments":"no"},
    "request": {"<Copy of request body>"}
  }
  

Update vote choices

Clients can update the voting preferences of their ticket at any time after after calling /payfee.

• POST /setvotechoices

  Request:

  {
    "timestamp":1590509066,
    "tickethash":"484a68f7148e55d05f0b64a29fe7b148572cb5272d1ce2438cf15466d347f4f4",
    "votechoices":{"headercommitments":"no"}
  }
  

  Response:

  {
    "timestamp":1590509066,
    "request": {"<Copy of request body>"}
  }