btc-project

btc-project

About this repo

This repository is the interview project for Anymind Group.

Directories

Frameworks and core dependencies

HTTP Framework: blademaster is an open source web framework based on Gin, which is developed by bilibili and is an excellent framework for production environment.

Cache: redis is the most widespread memory cache in the world.

Database: influxDB is an open source time series database.

Installation

1. Make sure redis and influxDB are installed and configured.
2. Clone this project git clone https://github.com/peterli110/btc-project.git $GOPATH/src/btc-project
3. Modify the [redis] and [influxdb] part in ./configs/config.toml if necessary.
4. Build the server by cd cmd and go build.
5. Run the server by ./cmd

Test

1. Make sure redis and influxDB are installed and configured.
2. Modify the [redis] and [influxdb] part in ./configs/config_test.toml if necessary.
3. Test with go test ./internal/... -v

Instruction

This server provides 2 APIs which accept requests with Content-Type: application/json.

Please note that since BTC is invented at the beginning of 2009, so all the time string must after 2008 and before or equal to current time.

POST /coin/add

{
	"datetime": "2020-02-19T12:34:00+00:00",
	"amount": 1.23
}

while datetime is a valid RFC 3339 time string,

amount is a positive float number which is the amount of btc.

Sample request:

curl --header "Content-Type: application/json" \
  --request POST \
  --data '{"datetime":"2020-02-19T10:28:00+00:00","amount":751.12}' \
  http://localhost:8000/coin/add

Response will be:

{
    "code": 0
}

POST /coin/search

{
	"startDatetime": "2020-02-19T12:34:00+00:00",
	"endDatetime": "2020-02-19T12:34:00+00:00"
}

while startDatetime and endDatetime are valid RFC 3339 time strings,

and endDatetime must after startDatetime.

Sample request:

curl --header "Content-Type: application/json" \
  --request POST \
  --data '{"startDatetime":"2020-02-19T08:12:00+00:00","endDatetime":"2020-02-20T08:32:00+00:00"}' \
  http://localhost:8000/coin/search

Response will be:

{
    "code": 0,
    "data": [
        {
            "datetime": "2020-02-19T10:00:00+00:00",
            "amount": 751.12
        },
        {
            "datetime": "2020-02-19T12:00:00+00:00",
            "amount": 1051.12
        }
    ]
}

Response will be always with a status http.StatusOK(200), and response body will be formatted in JSON, a sample response will be

{
		"code": 0,
		"data": [
		            "data will include search result as the response of /coin/search",
		            "and will not exist as the response of /coin/add"
                ]
}

Response Code

To simplify the project, I only use 3 response codes for convenience:

Constraints

Since the smallest unit of BTC is 10^-8, and the float calculation will lose precision, I converted the BTC to the smallest unit and use int64 to store and calculate. The InfluxDB is also use int64 to store integer values.

The maximum value of BTC that this project could store is MaxInt64 * 10^-8 = 9 * 10^10.