Garantex USDT Rates GRPC Service

A Go microservice that fetches the USDT exchange rate (ask/bid) from the Grinex exchange and exposes it via gRPC.
Exchange data is stored in PostgreSQL on every request.

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Features

• gRPC endpoint GetRates for retrieving USDT ask/bid prices
• Data fetched from Grinex API
• PostgreSQL integration
• Healthcheck endpoint
• Graceful shutdown
• Configurable via .yaml config and environment variables
• Dockerized with Docker Compose
• Linting and unit testing support

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🏁 Quick Start

1. Clone the repository

git clone https://github.com/Webblurt/garantex-usdt-rates.git
cd garantex-usdt-rates

2. Create .env file

cat <<EOF > .env
POSTGRES_USER=postgres
POSTGRES_PASSWORD=postgres
POSTGRES_DB=rates
EOF

3. Build the project

make build

4. Start services with Docker Compose

docker-compose up --build

The app will be available on localhost:50051 (gRPC port).

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Running Tests

make test

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Configuration

Configuration is managed via a YAML file and environment variables.

config/config.yaml

server:
  port: "50051"

postgres:
  dsn: "host=postgres port=5432 user=postgres password=postgres dbname=rates sslmode=disable"

grinex:
  url: "https://grinex.io/api/v2/depth"

Environment Variables (.env)

POSTGRES_USER=postgres
POSTGRES_PASSWORD=postgres
POSTGRES_DB=rates

You can override values in the config file using environment variables or command-line flags (if implemented).

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Makefile Commands

make build - Build the Go app make run - Run the app locally make test - Run unit tests make lint - Run code linter (golangci-lint) make docker-build - Build Docker image

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Healthcheck

A gRPC health check endpoint is available (standard grpc-health-probe compatible).

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Requirements

• Go 1.22+
• Docker & Docker Compose
• golangci-lint (for make lint)

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Running without Docker

go run ./cmd/app

Ensure PostgreSQL is running locally and credentials match config/config.yaml.

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GRPC API

GetRates (Unary)

Returns current USDT ask and bid prices with timestamp.

rpc GetRates (google.protobuf.Empty) returns (RateResponse);