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Pairs api v3

Version 3 of RESTful API for trading stocks (single or pairs), deployed on Heroku
Updated 9 months ago

Pairs-API v3 for trading tickers (single or pairs), deployed on Heroku & Dreamhost

Version 3 of the Flask-RESTful API.

Check this repository for the latest release: https://github.com/ozdemirozcelik/pairs-api

Built from the ground-up with Flask-RESTful & Flask-SQLAlchemy & Flask-JWT-Extended. Configured to be used with SQLite3 for local use.

A working demo for the latest release is deployed in Heroku with PostgreSQL:

https://api-pairs-v3.herokuapp.com/

Watch Demo

Watch on YouTube

Additions to v2

  • additional API resources
  • functionality to create server side sessions
  • functionality to work with TradingView webhooks (Release V3.O)
  • demo improvements:
    • new dashboard
    • list view for signals
  • functionality to work with Interactive Brokers TWS API (Release V3.1)
  • keep account position and PNL details
  • v3.3 works on heroku-22 stack

Use Cases

With Pairs-API v3 you can:

  • catch webhooks from trading platforms or signal generators
  • list, save, update and delete tickers/pairs, order and price details with API calls
  • enable and disable tickers and pairs for active trading
  • use access tokens for authentication purposes with login system backend
  • TODO: send real time orders to exchange (possibly via Interactive Brokers)
  • see account positions and PNL details

Considerations

Considering for the next version:

  • add statistical analysis and visualization
  • improve error handling, add unit tests
  • set up CI for the repository

Requirements

  • flask~=2.0.2
  • Flask-RESTful~=0.3.9
  • Flask-JWT-Extended~=4.4.0
  • flask-sqlalchemy~=2.5.1
  • flask-session~=0.4.0
  • pyjwt~=2.4.0
  • pytz~=2022.1
  • uwsgi~=2.0.20 (for Heroku deployment only)
  • psycopg2~=2.9.3 (for Heroku Postgres deployment only)

Installation

(commands in parentheses for anaconda prompt)

clone git repository:

$ git clone https://github.com/ozdemirozcelik/pairs-api-v3.git

create and activate virtual environment:

$ pip install virtualenv
(conda install virtualenv)

$ mkdir pairs-api
md pairs-api (windows)

$ cd pairs-api

$ python -m venv pairs-env
(conda create --name pairs-env)

$ source pairs-env/bin/activate
.\pairs-env\scripts\activate (windows)
(conda activate pairs-env)

install requirements:

IMPORTANT: check the need of using 'uwsgi' and 'psycopg2' from the requirements.txt before installing. These are mainly used for Heroku and Heroku Postgres.

(windows: change -if necessary- version declarations from 'flask~=2.0.2'' to 'flask==2.0.2')

$ pip install -r requirements.txt --user
(conda install --file requirements_conda.txt)

try this if conda fails to install requirements. or try with pip:

(conda config --append channels conda-forge)

check this out if you get an invalidversionspec error: https://github.com/conda/conda/issues/9519#issuecomment-690486632

run flask:

$ export FLASK_APP=app
$ export FLASK_ENV=development
$ set FLASK_DEBUG=1 
$ flask run

(windows)
set FLASK_APP=app
set FLASK_ENV=development
set FLASK_DEBUG=1 
flask run

browse to "http://127.0.0.1:5000/" to see the dashboard.

Authorization

webhooks

need a passphrase, by default it is set as 'webhook'; check signals.py:

PASSPHRASE = 'webhook'

default admin and a user

is created during database creation; check users.py::

@staticmethod
def default_users():
    # Add Default Users
    if not UserModel.find_by_username("admin"):
        admin = UserModel("admin", "123")
        admin.insert()
    if not UserModel.find_by_username("user1"):
        user = UserModel("user1", "123")
        user.insert()

resource authorization

needs currently set with Flask- JWT:

  • no token required:

    • POST signal
    • GET ticker & pair & signal
    • GET tickers & pairs
  • optional token required: "@jwt_required(optional=True)":

    • GET signals (get more signals if token is available )
  • fresh token required "@jwt_required(fresh=True)":

    • PUT, Delete signal
    • POST, PUT pair & ticker
  • admin rights & fresh token required "@jwt_required(fresh=True)":

    • DELETE signal & pair & ticker
    • GET, POST, PUT, DELETE user

Demo Configuration

app.py

resources/users.py

Demo is using custom created session management for server side sessions. If you want to use flask session, search and enable rows marked with "(flask-session-change)". Flask sessions may not be persistent in Heroku, works fine in local.

templates/setup.html

If the app is deployed remotely, a proxy can be activated to bypass CORS limitations. Proxy is set to "https://api-pairs-cors.herokuapp.com/" by default. Check if you need the enable the following lines before deployment:

(base.html)(setup.html)
// Edit your proxy and enable to overcome CORS limitations
// if (server_url != "http://127.0.0.1:5000/") {
//    const updatedURL = server_url.replace(/^https:\/\//i, 'http://');
//    var proxy_url = "https://api-pairs-cors.herokuapp.com/";
//    server_url = proxy_url + updatedURL;
//};

Check Heroku deployment to learn for more about using your own proxy server on Heroku.

Resources

Resources defined with flask_restful are:

api.add_resource(SignalWebhook, "/v3/webhook")
api.add_resource(SignalUpdateOrder, "/v3/signal/updateorder")
api.add_resource(SignalList, "/v3/signals/<string:number_of_items>")
api.add_resource(SignalListStatus,"/v3/signals/status/<string:order_status>/<string:number_of_items>",)
api.add_resource(SignalListTicker, "/v3/signals/ticker/<string:ticker_name>/<string:number_of_items>")
api.add_resource(Signal, "/v3/signal/<string:rowid>")

api.add_resource(PairRegister, "/v3/regpair")
api.add_resource(PairList, "/v3/pairs/<string:number_of_items>")
api.add_resource(Pair, "/v3/pair/<string:name>")

api.add_resource(TickerRegister, "/v3/regticker")
api.add_resource(TickerUpdatePNL, "/v3/ticker/updatepnl")
api.add_resource(TickerList, "/v3/tickers/<string:number_of_items>")
api.add_resource(Ticker, "/v3/ticker/<string:symbol>")

api.add_resource(UserRegister, "/v3/reguser")
api.add_resource(UserList, "/v3/users/<string:number_of_users>")
api.add_resource(User, "/v3/user/<string:username>")
api.add_resource(UserLogin, "/v3/login")
api.add_resource(UserLogout, "/v3/logout")
api.add_resource(TokenRefresh, "/v3/refresh")

api.add_resource(PNLRegister, "/v3/regpnl")
api.add_resource(PNLList, "/v3/pnl/<string:number_of_items>")

Request & Response Examples

Please check the POSTMAN collection to test all resources.

POST request to register a single ticker:

'http://api-pairs-v3.herokuapp.com/v3/regticker'

Request Body:

{
    "symbol": "AAPL",
    "prixch": "SMART",
    "secxch": "NASDAQ",
    "active": 1
}

Response:

{
    "message": "Stock created successfully."
}

PUT request to update a single ticker:

'http://api-pairs-v3.herokuapp.com/v3/regticker'

Request Body:

{
    "symbol": "AAPL",
    "prixch": "SMART",
    "secxch": "NASDAQ",
    "active": 1
}

Response:

{
    "symbol": "AAPL",
    "prixch": "ISLAND",
    "secxch": "BYX",
    "active": 0
}

GET request to get all tickers:

'http://api-pairs-v3.herokuapp.com/v3/tickers/0'

GET request to receive certain number of tickers (for exp: 50):

'http://api-pairs-v3.herokuapp.com/v3/tickers/2'

Response:

{
    "tickers": [
        {
            "symbol": "AAPL",
            "prixch": "SMART",
            "secxch": "NASDAQ",
            "active": 1
        },
        {
            "symbol": "DRH",
            "prixch": "SMART",
            "secxch": "SMART",
            "active": 1
        }
    ]
}

GET request to get details of a certain ticker:

'http://api-pairs-v3.herokuapp.com/v3/ticker/AAPL'

Response:

{
    "symbol": "AAPL",
    "prixch": "SMART",
    "secxch": "NASDAQ",
    "active": 1
}

DELETE request for a certain ticker:

'http://api-pairs-v3.herokuapp.com/v3/ticker/AAPL'

Response:

{
    "message": "Item deleted"
}

POST request to register a pair:

'http://api-pairs-v3.herokuapp.com/v3/regpair'

Request Body:

{
    "ticker1": "MA",
    "ticker2": "V",
    "hedge": 1.3,
    "status": 0
}

Response:

{
    "message": "'pair' created successfully."
}

PUT request to update a pair:

'http://api-pairs-v3.herokuapp.com/v3/regpair'

Request Body:

{
    "name": "MA-V",
    "ticker1": "MA",
    "ticker2": "V",
    "hedge": 1.4,
    "status": 1
}

Response:

{
    "name": "MA-V",
    "ticker1": "MA",
    "ticker2": "V",
    "hedge": 1.4,
    "status": 1,
    "notes": null
}

POST request to register a webhook signal:

'http://api-pairs-v3.herokuapp.com/v3/webhook'

Request Body:

{
    "passphrase": "webhook",
    "ticker": "AAPL",
    "order_action": "buy",
    "order_contracts": "100",
    "order_price": "400.2",
    "mar_pos": "long",
    "mar_pos_size": "100",
    "pre_mar_pos": "flat",
    "pre_mar_pos_size": "0",
    "order_comment": " Enter Long",
    "order_status": "waiting"
}

Response:

{
    "message": "Signal created successfully."
}

GET request to get a list of signals with certain trade status

'http://api-pairs-v3.herokuapp.com/v3/signals/status/waiting/2'

Response:

{
    "signals": [
        {
            "rowid": 34,
            "timestamp": "2022-05-27 00:24:17",
            "ticker": "NMFC-0.72*NASDAQ:ROIC",
            "order_action": "buy",
            "order_contracts": 100,
            "order_price": -0.01,
            "mar_pos": "long",
            "mar_pos_size": 100,
            "pre_mar_pos": "flat",
            "pre_mar_pos_size": 0,
            "order_comment": "Enter Long(...)",
            "order_status": "waiting",
            "ticker_type": "pair",
            "stk_ticker1": "NMFC",
            "stk_ticker2": "ROIC",
            "hedge_param": 0.72,
            "order_id1": null,
            "order_id2": null,
            "stk_price1": null,
            "stk_price2": null,
            "fill_price": null,
            "slip": null,
            "error_msg": null
        },
        {
            "rowid": 27,
            "timestamp": "2022-05-26 21:16:49",
            "ticker": "NMFC-0.72*NASDAQ:ROIC",
            "order_action": "buy",
            "order_contracts": 100,
            "order_price": -0.01,
            "mar_pos": "long",
            "mar_pos_size": 100,
            "pre_mar_pos": "flat",
            "pre_mar_pos_size": 0,
            "order_comment": "Enter Long(...)",
            "order_status": "waiting",
            "ticker_type": "pair",
            "stk_ticker1": "NMFC",
            "stk_ticker2": "ROIC",
            "hedge_param": 0.72,
            "order_id1": null,
            "order_id2": null,
            "stk_price1": null,
            "stk_price2": null,
            "fill_price": null,
            "slip": null,
            "error_msg": null
        }
    ]
}

PUT request to update order price and status by order id

'http://api-pairs-v3.herokuapp.com/v3/signal/updateorder'
"cancel":true to cancel the order

Request Body:

{
    "passphrase": "webhook",
    "symbol": "ROIC",
    "order_id": 8,
    "price": 15.55,
    "filled_qty": 100
}

Response: (fill_price & slip & order status for partially filled orders are calculated automatically)

{
    "rowid": 5,
    "ticker": "NMFC-0.75*ROIC",
    "order_action": "buy",
    "order_contracts": 603,
    "order_price": 0.98,
    "mar_pos": "long",
    "mar_pos_size": 603,
    "pre_mar_pos": "flat",
    "pre_mar_pos_size": 0,
    "order_comment": "Enter Long",
    "order_status": "part.filled",
    "ticker_type": "pair",
    "ticker1": "NMFC",
    "ticker2": "ROIC",
    "hedge_param": 0.75,
    "order_id1": 7,
    "order_id2": 8,
    "price1": 12.6,
    "price2": 15.55,
    "fill_price": 0.9375,
    "slip": 0.0425,
    "error_msg": null,
    "status_msg": "remained(ROIC): 352.0"
}

POST request to login with a user

'http://api-pairs-v3.herokuapp.com/v3/login'

Request Body (Token to expire in 30 min, default is 10 min):

{
    "username": "user1",
    "password": "123",
    "expire":30
}

Response:

{
    "access_token": "eyJ0eXAx...",
    "refresh_token": "eyJ0eXC...",
    "expire": 30
}

Status Codes

Pairs-API v3 returns the following status codes:

Status Code Description
200 OK
201 CREATED
400 BAD REQUEST
404 NOT FOUND
500 INTERNAL SERVER ERROR

Heroku Deployment:

Download and install Heroku CLI.

Clone repository, login to Heroku, add git remote and push:

$ git clone https://github.com/ozdemirozcelik/pairs-api-v3.git
$ heroku login
$ heroku git:remote -a [your-heroku-app-name]
$ git push heroku main

To enable PostgreSQL in your Heroku account:

  • go to Resources in your Heroku account and install 'Heroku Postgres'
  • go to Settings->Config Vars
  • copy 'DATABASE_URL' value which should look like 'postgres://sdfyebdbfbf..'
  • add a new system variable 'DATABASE_URL_SQLALCHEMY' and paste the value
  • change 'postgre' to 'postgresql' and save, it should look like: 'postgresql://sdfyebdbfbf..'

See the links below to add CORS headers to the proxied request:

https://github.com/Rob--W/cors-anywhere

https://dev.to/imiebogodson/fixing-the-cors-error-by-hosting-your-own-proxy-on-heroku-3lcb

DreamHost Shared Hosting Deployment:

Please follow the instructions here:

DreamHost Shared Hosting Deployment

TradingView as the signal generator:

You can use below template for TradingView to send a POST request as soon as an alert is triggered.

webhook URL should be: '{URL_OF_YOUR_API}/v3/webhook'

(local\webhook.json)

{
    "passphrase": "webhook",
    "ticker": "{{ticker}}",
    "order_action": "{{strategy.order.action}}",
    "order_contracts": {{strategy.order.contracts}},
    "order_price": {{strategy.order.price}},
    "mar_pos": "{{strategy.market_position}}",
    "mar_pos_size": {{strategy.market_position_size}},
    "pre_mar_pos": "{{strategy.prev_market_position}}",
    "pre_mar_pos_size": {{strategy.prev_market_position_size}},
    "order_comment": "{{strategy.order.comment}}"
}

Demo:

https://api-pairs-v3.herokuapp.com/

Using with Interactive Brokers

Recommended to be used with Interactive Brokers. Check my repository: PAIRS-IBKR

Acknowledgements

snippets:

Contributing

Pull requests are welcome.