Copy contents of altcoin defcoind to a postgres database

populate-defcoin.rb

=begin

WARNING - I think this goes without saying for random gists you find on the internet, but you 
probably shouldn't use this in production. 


For every altcoin you want to store, create this schema:

CREATE SCHEMA altcoin;

CREATE TABLE altcoin.block (
	hash character varying PRIMARY KEY,
	details json
);

CREATE TABLE altcoin.transaction (
	hash character varying PRIMARY KEY,
	block_hash character varying,
	details json,
	status character varying
);



Todo:
Validate
 	Missing Blocks
	Incomplete Blocks (Missing Transactions)
	
=end





require 'net/http'
require 'uri'
require 'json'
require 'pg'
 
$altcoin = 'defcoin' 
$rpc_url = 'http://user:password@127.0.0.1:1338'
$db_url  = 'host=127.0.0.1 dbname=pgcoin'
 
# This number should not be higher than the number of connections allowed by postgres
$max_threads = 90

# This class is just a copy from the Bitcoin class shared here: https://en.bitcoin.it/wiki/API_reference_(JSON-RPC)  
class CoinRPC
  def initialize(service_url)
    @uri = URI.parse(service_url)
  end
 
  def method_missing(name, *args)
    post_body = { 'method' => name, 'params' => args, 'id' => 'jsonrpc' }.to_json
    resp = JSON.parse( http_post_request(post_body) )
    raise JSONRPCError, resp['error'] if resp['error']
    resp['result']
  end
 
  def http_post_request(post_body)
    http    = Net::HTTP.new(@uri.host, @uri.port)
    request = Net::HTTP::Post.new(@uri.request_uri)
    request.basic_auth @uri.user, @uri.password
    request.content_type = 'application/json'
    request.body = post_body
    http.request(request).body
  end
 
  class JSONRPCError < RuntimeError; end
end
 
 

def insertBlock block

  conn = PG.connect($db_url)
  
  conn.prepare('InsertBlock', 'insert into defcoin.block (hash, details) values ($1, $2)')
  conn.prepare('InsertGenesisTX', 'insert into defcoin.transaction (hash, block_hash) values ($1, $2)')
  conn.prepare('InsertTX', 'insert into defcoin.transaction (hash, block_hash, details) values ($1, $2, $3)')
  
  conn.exec_prepared('InsertBlock', [ block["hash"], JSON.generate(block) ])
  
  block["tx"].each do |tx_hash|
    if block["height"] == 0
      conn.exec_prepared('InsertGenesisTX', [ tx_hash, block["hash"] ])
    else 
      t = CoinRPC.new($rpc_url) 	
      transaction = t.decoderawtransaction(t.getrawtransaction(tx_hash))
      conn.exec_prepared('InsertTX', [ transaction["txid"], block["hash"], JSON.generate(transaction) ])
    end
  end
	
  conn.finish
  Thread.exit
end


def getLastSyncedBlock 

  conn = PG.connect($db_url)
  res  = conn.exec('SELECT details->>\'hash\' as h from defcoin.block order by (details->>\'height\')::integer DESC LIMIT 1 ')
  
  unless res.cmd_tuples() == 0
    lastBlockHash = res[0]['h']
  end

  conn.finish
  lastBlockHash

end


if $0 == __FILE__
  h = CoinRPC.new($rpc_url)

  p 'Checking for last stored block'
  startingBlock = getLastSyncedBlock() 
  if startingBlock.nil?
    p 'Could not find a block, starting at the Genesis'
    block = h.getblock(h.getblockhash(0))
    p block["hash"]
    Thread.new{insertBlock(block)}
  else 
    p startingBlock
    block = h.getblock(startingBlock)
    p 'Next Hash Found ' + block["hash"]   
  end
  
  
  nextBlockHash = block["nextblockhash"]
  
  while true
    if Thread.list.count < $max_threads
      begin
        while nextBlockHash.nil? 
		p "Up to date, sleeping"
 		p block["hash"]
	      sleep 60
          block = h.getblock(block["hash"])
          nextBlockHash = block["nextblockhash"]
        end
        block = h.getblock(nextBlockHash)
        nextBlockHash = block["nextblockhash"]
        Thread.new{insertBlock(block)}
      rescue
        p nextBlockHash
      end
    end
  end
end