Currency Exchange Server - Golang

Swap allows you to retrieve currency exchange rates from various services such as Google, Yahoo, Fixer, CurrencyLayer or 1Forge and optionally cache the results.

Playground

/GET Examples for single exchanger:

• GET /convert?from=USD&to=AED&amount=2&exchanger=yahoo
• GET /convert?from=EUR&to=GBP&amount=1&exchanger=google&cacheTime=300s
• GET /convert?from=USD&to=SAR&amount=1&exchanger=themoneyconverter

/POST Examples for single or multi exchanger:

• CURL examples:

  curl -X POST \
    https://go-swap-server.herokuapp.com/convert \
    -H 'Content-Type: application/json' \
    -d '{
    "amount": 2.5,
    "from": "USD",
    "to": "AED",
    "decimalPoints": 4,
    "cacheTime": "120s",
    "exchanger": [
      {
        "name": "yahoo"
      },
      {
        "name": "google"
      },
      {
        "name": "themoneyconverter",
        "userAgent": "Mozilla/5.0 (Macintosh; Intel Mac OS X 10.8; rv:21.0) Gecko/20100101 Firefox/21.0"
      }
    ]
  }'
  
   # Response example
   # {
   #    "to": "AED",
   #    "from": "USD",
   #    "exchangerName": "yahoo",
   #    "exchangeValue": 3.6721,
   #    "originalAmount": 2.5,
   #    "convertedAmount": 9.1802,
   #    "convertedText": "2.5 USD is worth 9.1802 AED",
   #    "rateDateTime": "2018-09-30T07:45:45Z",
   #    "rateFromCache": false
   # }  

• Run in SwaggerUI
• 

QuickStart

# Or using docker  
$ docker pull meio/go-swap-server:latest && \
  docker run --rm --name go-swap-server -p 5000:5000 -it meio/go-swap-server:latest

Programmatically

$ go get github.com/me-io/go-swap

package main

import (
	"fmt"
	ex "github.com/me-io/go-swap/pkg/exchanger"
	"github.com/me-io/go-swap/pkg/swap"
)

func main() {
	SwapTest := swap.NewSwap()

	SwapTest.
		AddExchanger(ex.NewGoogleApi(nil)).
		Build()

	euroToUsdRate := SwapTest.Latest("EUR/USD")
	fmt.Println(euroToUsdRate.GetRateValue())
}

Features

• Convert with Single exchange source /GET
• Convert with Multi exchange sources with fallback mechanism /POST
  • Google
  • Yahoo
  • CurrencyLayer
  • Fixer.io
  • themoneyconverter.com
  • openexchangerates.org
  • 1forge.com
• Rate Caching - 120s Default
  • Memory - Default
  • Redis
• Rate decimal points rounding 4 Default
• Swagger UI
• Clear API Request and Response
• Docker image, Binary release and Heroku Demo
• Clear documentation and 90%+ code coverage
• Unit tested on live and mock data

Screens

Documentation

The documentation for the current branch can be found here.

Services

Exchanger	type	#	$
Google	HTML / Regex	✔️	Free
Yahoo	JSON / API	✔️	Free
Currency Layer	JSON / API	✔️	Paid - ApiKey
Fixer.io	JSON / API	✔️	Paid - ApiKey
1forge	API	✔️	Freemium / Paid - ApiKey
The Money Converter	HTML / Regex	✔️	Free
Open Exchange Rates	API	✔️	Freemium / Paid - ApiKey

Uptime Monitor

TODO LIST

• error structure for empty json or regex not matched
• convert panic to api json error
• increase tests
• verbose logging
• godoc
• static bundle public folder ./cmd/server/public
• v 1.0.0 release ( docker / binary github / homebrew mac )
• support historical rates if possible
• benchmark & performance optimization memory leak
• contributors list

Contributing

Anyone is welcome to contribute, however, if you decide to get involved, please take a moment to review the guidelines:

• Only one feature or change per pull request
• Write meaningful commit messages
• Follow the existing coding standards

Credits

Inspired by florianv/swap

License

The code is available under the MIT license.