Accessing steemd RPC programatically using Golang

steemd_rpc_example.go

package main

import (
	"flag"
	"fmt"
	"log"
	"net/rpc/jsonrpc"
	"time"

	"golang.org/x/net/websocket"
)

func main() {
	if err := run(); err != nil {
		log.Fatalln("Error:", err)
	}
}

type Config struct {
	BlockInterval int `json:"STEEMIT_BLOCK_INTERVAL"`
}

type DynamicGlobalProperties struct {
	LastIrreversibleBlockNum int `json:"last_irreversible_block_num"`
}

func run() error {
	// Process flags.
	flagAddress := flag.String("rpc_endpoint", "ws://localhost:8090", "steemd RPC endpoint address")
	flag.Parse()

	// Dial the connection to the JSON-RPC endpoint.
	addr := *flagAddress
	log.Println("---> CONNECT", addr)
	conn, err := websocket.Dial(addr, "", "http://localhost")
	if err != nil {
		return err
	}
	defer conn.Close()

	// Instantiate a JSON-RPC client.
	client := jsonrpc.NewClient(conn)

	// Get config.
	log.Println("---> CALL get_config")
	var config Config
	if err := client.Call("get_config", nil, &config); err != nil {
		return err
	}

	// Loop in a similar way as in the Python example.
	lastBlock := 160900
	for {
		log.Println("---> CALL get_dynamic_global_properties")
		var props DynamicGlobalProperties
		if err := client.Call("get_dynamic_global_properties", nil, &props); err != nil {
			return err
		}

		for props.LastIrreversibleBlockNum-lastBlock > 0 {
			log.Printf("---> CALL get_block %v", lastBlock)
			var block map[string]interface{}
			if err := client.Call("get_block", lastBlock, &block); err != nil {
				return err
			}

			fmt.Println(block)
			lastBlock++
		}

		time.Sleep(time.Duration(config.BlockInterval) * time.Second)
	}
}