Differential D3443 Diff 9728 contrib/devtools/fetch-chainparams.py

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contrib/devtools/fetch-chainparams.py

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				#!/usr/bin/env python3
				# Copyright (c) 2019 The Bitcoin developers
				# Distributed under the MIT software license, see the accompanying
				# file COPYING or http://www.opensource.org/licenses/mit-license.php.

				import argparse
				import json
				import subprocess
				import sys

				parser = argparse.ArgumentParser(description=(
				"Fetch a block's chainparams values from the bitcoin HTTP RPC"
				"(nMinimumChainWork and defaultAssumeValid).\n\n"
				"NOTE: bitcoind must have `--rest=1` set (either as a cli argument or in"
				"the config)!"), formatter_class=argparse.RawTextHelpFormatter)
				parser.add_argument('--hostaddr', '-a',
				default="localhost",
				help="Host address of the HTTP RPC bitcoind server to call"
				"for fetching chain info. (defaults to `localhost`)")
				parser.add_argument('--hostport', '-p',
				help="Host port of the HTTP RPC bitcoind server to call"
				"for fetching chain info. (defaults to 8332 on mainnet and 18332 on testnet)")
				parser.add_argument('--testnet', '-t', action="store_true",
				help="If set, testnet chainparams will be updated instead"
				"of mainnet chainparams. If testnet is set, but hostport is not set, hostport will default to 18332.")
				parser.add_argument('--blockhash', '-b',
				help="(optional) The block hash to update chainparams"
				"with. If not specified, bestblockhash is used.")
				args = parser.parse_args()


				def curl(url):
				# Call bitcoin HTTP RPC using curl
				print("Fetching URL: {}".format(url), file=sys.stderr)
				curlArgs = ['curl', '-s', url]
				p = subprocess.Popen('curl -s ' + url, stdout=subprocess.PIPE, shell=True)
				output = p.communicate()[0]
				status = p.wait()
				if status != 0:
				print("curl error status: {}\nSee https://curl.haxx.se/libcurl/c/libcurl-errors.html for error descriptions.".format(status), file=sys.stderr)
				exit(1)
				output = output.decode('utf-8')
				try:
				return json.loads(output)
				except:
				print("Error while parsing JSON:\n{}".format(sys.exc_info()), file=sys.stderr)
				print("Output from HTTP RPC call:\n{}".format(output), file=sys.stderr)
				exit(2)


				port = args.hostport
				if not port:
				port = '18332' if args.testnet else '8332'
				url = args.hostaddr + ':' + port

				# Get best block hash and chainwork
				chaininfo = curl(url + '/rest/chaininfo.json')

				if (args.testnet is True and chaininfo['chain'] != 'test') or (args.testnet is False and chaininfo['chain'] != 'main'):
				print("The chain network specified did not match the one given by the host node!", file=sys.stderr)
				print("Did you mean to call with a different `--hostaddr` or `--hostport`, or with `--testnet` set?", file=sys.stderr)
				exit(3)

				blockhash = chaininfo['bestblockhash']
				chainwork = chaininfo['chainwork']
				if args.blockhash:
				blockhash = args.blockhash
				print("Fetching chainwork for block {}".format(blockhash), file=sys.stderr)
				block = curl(url + '/rest/block/' + blockhash + '.json')
				chainwork = block['chainwork']

				print(json.dumps({'chainwork': chainwork, 'blockhash': blockhash}))
				deadalnixUnsubmitted Not Done Inline Actions Generating a JSON is not useful. The RPC already provide all of this in JSON form, so this does exactly nothing useful. Simply shuffle around JSON fields. deadalnix: Generating a JSON is not useful. The RPC already provide all of this in JSON form, so this does…