Koios API Client Library for Go

Overview

A GO package for Cardano Blockchain using Koios API

Below there is an example to study, while to see the full koios-go-client documentation you can find it here

Install

Tips

To install the module, type the following command:

go get github.com/cardano-community/koios-go-client/v3

Import the module

Tips

To use the module, see the following example:

import (
  "github.com/cardano-community/koios-go-client/v3" // imports as package "koios"
)

Examples

Basic usage

package main

import (
	"context"
	"fmt"
	"log"

	koios "github.com/cardano-community/koios-go-client/v3"
)

func main() {
  // Call to koios.New without options is same as calling it with default opts.
  // See godoc for available configuration options.
  // api, err := koios.New(
  // 	koios.Host(koios.MainnetHost),
  // 	koios.APIVersion(koios.DefaultAPIVersion),
  // 	koios.Port(koios.DefaultPort),
  // 	koios.Schema(koios.DefaultSchema),
  // 	koios.HttpClient(koios.DefaultHttpClient),
  // ).
  api, err := koios.New()
  if err != nil {
    log.Fatal(err)
  }

  res, err := api.GetTip(context.Background(), nil)
  if err != nil {
	  log.Fatal(err)
  }
  fmt.Println("status: ", res.Status)
  fmt.Println("statu_code: ", res.StatusCode)

  fmt.Println("abs_slot: ", res.Data.AbsSlot)
  fmt.Println("block_no: ", res.Data.BlockNo)
  fmt.Println("block_time: ", res.Data.BlockTime)
  fmt.Println("epoch: ", res.Data.Epoch)
  fmt.Println("epoch_slot: ", res.Data.EpochSlot)
  fmt.Println("hash: ", res.Data.Hash)
}

Concurrency

func main() {
  api, _ := koios.New(
    // limit client request 1 per second even though
    // this example will send requests in goroutines.
    koios.RateLimit(1),
  )
  ctx := context.Background()
  var wg sync.WaitGroup
  servers := []string{
    koios.GuildHost,
    koios.PreviewHost,
    koios.TestnetHost,
    koios.MainnetHost,
    koios.PreProdHost,
    koios.MainnetHost,
    koios.MainnetHostEU,
  }

  // Thanks to rate limit option requests will be made
  // once in a second.
  for _, host := range servers {
    wg.Add(1)
    go func(ctx context.Context, host string) {
      defer wg.Done()
      // switching host by creating light clone of client
      // with new options
      client, err := api.WithOptions(koios.Host(host))
      res, _ := client.GET(ctx, "/tip", nil)
      defer res.Body.Close()
      body, _ := io.ReadAll(res.Body)
      fmt.Println("Host: ", host)
      fmt.Println("Response: ", string(body))
    }(ctx, host)
  }

  wg.Wait()
}