Our API includes various endpoints that involve on-chain activities and updates, such as ownership verification and smart contract deployment. In order to provide smooth experience and maximum level of security, we employ cryptographic challenges and signatures tailored to each supported blockchain.
Account Creation
To create a new account for the customer and set it up for fund transfers with OffBlocks, we need to deploy a smart-contract account to the respective blockchain. The customer remains the ultimate owner of this account, and to manage funds for off-chain transactions on the user's behalf, we need them to sign a session key issued in the form of a cryptographic challenge. Similar to other endpoints, the challenge returned by the endpoint is a Base64-encoded string.
Create new customer account
post
/customers/{customerId}/accounts
Creates new account for the customer and generates a challenge to be signed in order to create a related blockchain account
Authorizations
AuthorizationstringRequired
Bearer authentication header of the form Bearer <token>.
Path parameters
customerIdstring · uuidRequired
Unique customer ID
Header parameters
SignaturestringRequired
HTTP message signature
Signature-InputstringRequired
HTTP message signature input
Idempotency-Keystring · uuidRequired
Idempotency key (UUID)
Content-DigeststringRequired
Content digest
Body
typestring · enumRequired
Type of the account
Possible values:
currenciesstring[]Required
Currencies of the account, at least one is required (ISO-4217)
Responses
201
Successful operation
application/json
400
Invalid request
401
Not authorised
404
Customer not found
500
Internal error
post
/customers/{customerId}/accounts
To submit a signed challenge, please use the corresponding endpoint.
Sign previously issued account challenge
post
/accounts/{accountId}/challenge/sign
Signs previously issued challenge to sign account creation or deletion transaction on-chain
Authorizations
AuthorizationstringRequired
Bearer authentication header of the form Bearer <token>.
Path parameters
accountIdstring · uuidRequired
Unique account ID
Header parameters
SignaturestringRequired
HTTP message signature
Signature-InputstringRequired
HTTP message signature input
Idempotency-Keystring · uuidRequired
Idempotency key (UUID)
Content-DigeststringRequired
Content digest
Body
Cryptographic signature generated using owner's EOA private key according to chain-specific algorithm. Signature is used for signing on-chain transactions such as creating a new account, authorising a recurring payment or setting up spending limits
ownerIdstringRequired
Unique signer account ID in a form of a valid on-chain address
If, for any reason, the original challenge is lost or cannot be signed immediately, you can fetch it again using a dedicated endpoint. If we encounter an error during signature validation via /sign endpoint, a new challenge will be issued for you to retrieve.
Retrieve account challenge
get
/accounts/{accountId}/challenge
Retrieves challenge to sign account creation or deletion transaction on-chain. This operation invalidates any previously issued challenges for the account
Authorizations
AuthorizationstringRequired
Bearer authentication header of the form Bearer <token>.
POST /v1/accounts/{accountId}/challenge/sign HTTP/1.1
Host: api.offblocks.xyz
Authorization: Bearer YOUR_SECRET_TOKEN
Signature: text
Signature-Input: text
Idempotency-Key: 123e4567-e89b-12d3-a456-426614174000
Content-Digest: text
Content-Type: application/json
Accept: */*
Content-Length: 415
{
"ownerId": "eip155:1:0xab16a96D359eC26a11e2C2b3d8f8B8942d5Bfcdb",
"challenge": "LS0tLS1CRUdJTiBQVUJMSUMgS0VZLS0tLS0KTUZZd0VBWUhLb1pJemowQ0FRWUZLNEVFQUFvRFFnQUUzTEw1RldmVFgvL3BJaXNEL0xneFVIT2lxdlFTSUVWTgpGekloOTdLZXBlWk1iZVZsUGd1akZ4Yk5MN2x1ZVhRQnBpUWUzNmZLN0xSbXZNNHdEaWZFTkE9PQotLS0tLUVORCBQVUJMSUMgS0VZLS0tLS0=",
"signature": "IfvwaW1eCqLvQaK0/7YjvK8HBGHWHPclHHQWH4L+w6Q3CFS8CjSzq0h8G8AhzTGMc0xRrik3TyvrDm8t1JtL9Bw="
}
GET /v1/accounts/{accountId}/challenge HTTP/1.1
Host: api.offblocks.xyz
Authorization: Bearer YOUR_SECRET_TOKEN
Signature: text
Signature-Input: text
Accept: */*
