Purpose

This repository contains the backend of TradingLab.

It is written in Golang using Postgresql as database.

The code is hosted on DigitalOceans.

There are two main branches: production and staging.

The code is automatically re-compiled at any changes, so it is possibile to simply refresh the webpage to run the new code.

Architecture

The router is Gorilla Mux, using http and websocket.

To allow a dynamic experience to the users, the trading section creates a websocket which is called every time there is a change in the page, returning fresh processed data. In this way if multiple users are watching the same page, they will be all updated almost in real-time, almost at the same time.

In order to know when a user interacts with the platform, a specific Postgresql function is triggered, requiring to the server to activate a specific websocket.

Each new websocket is stored in the variable trades_wss:

type TradesSnapshot struct {
	UserDetails    UserDetails
	Trades         []Trade
	CountTrades    int
	TotalReturnUsd float64
	TotalReturnBtc float64
	Roi            float64
}

type WsTrade struct {
	UserToSee User
	RequestId string
	Channel   chan TradesSnapshot
	Ws        *websocket.Conn
}

trades_wss = make(map[string][]WsTrade)

In this way, every time user_a wants to see the profile of user_b:

1. send initial snapshot
2. instanciate websocket
3. add to trades_wss: user_b as key and user_a as value
4. if user_b makes a change, get trades_wss[user_b], obtaining user_a
5. if user_a closes the page the websocket is deleted from trades_wss

Run

Set environmental variables:

export TL_APP_ENV=
export TL_DB_USER=
export TL_DB_PASS=
export TL_DB_HOST=
export TL_DB_PORT=
export DO_KEY=
export DO_SECRET=
export CDN_PATH=
export ADMIN_TOKEN=
export CONTRACT_SUBSCRIPTION=
export MOONBEAM_ENDPOINT=
export DISCORD_WEBHOOK_URL=

Build and run the program:

modd

Test

go test -v -cover -parallel 1

To visualise test coverage

go test -v -parallel 1 -coverprofile=coverage.html && go tool cover -html=coverage.html

Migrate

Use Makefile to migrate up or down the database To clean migration, after making sure everything is correct, fix the table "schema_migrations" in the database.

Docs

swag init -ot go,yaml