A simple showcase of a transfer HTTP Rest API written in go.
The goal of the exercise is to be able transfer funds between wallets, both between users
- User can have one or more wallets.
- Transaction are operations that affect the balance of wallets; this allows transfers between users, as the exercise requires, but supports transfer between wallets of the same user too.
- Conversion between currencies has been left out of the scope.
- A simple basic authentication has been used for simplicity, leaving other safer but more complex solutions out (In. ex. expirable tokens and signed requests.)
- This README includes the API documentation, ideally a better doc should be used, for example OpenAPI specs.
The API uses HTTP Basic authentication for simplicity. leaving other safer but more complex solutions out (In. ex. expirable tokens and signed requests.)
Authorization: Basic base64("user_login:user_pass")
Example for user A in the fixtures:
Authorization: Basic dXNlcl9hOnVzZXJfYV9wYXNz
- Method:
GET - Path:
/api/v1/wallet/{walletID}
Examples:
curl 'http://localhost:8080/api/v1/wallet/2f9b76dd-f689-456e-9080-6789718018a5' \
--header 'Authorization: Basic dXNlcl9hOnVzZXJfYV9wYXNz'
{
"id": "2f9b76dd-f689-456e-9080-6789718018a5",
"user_id": "bbc00191-b064-4655-9075-261ccef978cb",
"balance": 12.75
}
Returns a list of transactions ordered by date.
- Method:
GET - Path:
/api/v1/wallet/{walletID}/transactions - QueryParameters:
per_page (integer): Number of results to return; Default:20.from_id (uuid): Option parameters that can be used to select the start transaction for the current page.order (asc|desc): Can be used to select the order of the results. Default:asc
Example:
curl 'http://localhost:8080/api/v1/wallet/2f9b76dd-f689-456e-9080-6789718018a5/transactions' \
--header 'Authorization: Basic dXNlcl9hOnVzZXJfYV9wYXNz'
{
"results": [
{
"id": "9177ad78-e5d5-4d3c-be8c-e0e1f44bbdcc",
"amount": 20,
"balance": 20,
"transaction_type": "deposit",
"reference_id": null,
"date": "2020-09-20T10:00:00Z"
},
{
"id": "4bce4401-6b35-4fa1-94b9-ac5ce05d29b1",
"amount": -7.25,
"balance": 12.75,
"transaction_type": "transfer",
"reference_id": "97ca2b73-7988-4247-82d4-f6ba723a99c9",
"date": "2020-09-20T11:10:00Z"
}
],
"next_id": null
}
- Method:
POST - Path:
/api/v1/wallet/{walletID}/transfer - Content-Type:
application/json - RequestBody:
destination_wallet_id (uuid): Destination wallet id.amount (decimal): the amount to transfer, cannot be zero or less.message (string): Custom message.
Example:
curl -X POST 'http://localhost:8080/api/v1/wallet/2f9b76dd-f689-456e-9080-6789718018a5/transfer' \
--header 'Content-Type: application/json' \
--header 'Authorization: Basic dXNlcl9hOnVzZXJfYV9wYXNz' \
--data-raw '{
"destination_wallet_id": "4e1d841d-e53f-4785-ba4d-99df05f11eee",
"amount": 10,
"message": "Happy Birthday!"
}'
{
"id": "d2964584-701a-4525-ba97-4963081a43d4",
"issuer_id": "bbc00191-b064-4655-9075-261ccef978cb",
"origin_wallet_id": "2f9b76dd-f689-456e-9080-6789718018a5",
"destination_wallet_id": "4e1d841d-e53f-4785-ba4d-99df05f11eee",
"amount": 10,
"message": "Happy Birthday!",
"date": "2020-09-21T00:01:58.939549Z"
}
TL;DR
make up
make fixtures
To start the local development environment:
make up
To rebuild the images
make build
To stop it:
make stop
To destroy it:
make down
A set of fixtures can be re-loaded once the DB is ready.
make fixtures
make api
Unit tests
make unit
All tests: unit + integration tests
make test