import blockchain.info utxo provider client from pybitcoin

blockstack_client/backend/utxo/blockchain_info.py

@@ -0,0 +1,93 @@
+#!/usr/bin/env python2
+# -*- coding: utf-8 -*-
+"""
+    Blockstack-client
+    ~~~~~
+    copyright: (c) 2014-2015 by Halfmoon Labs, Inc.
+    copyright: (c) 2016 by Blockstack.org
+
+    This file is part of Blockstack-client.
+
+    Blockstack-client is free software: you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    Blockstack-client is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+    You should have received a copy of the GNU General Public License
+    along with Blockstack-client. If not, see <http://www.gnu.org/licenses/>.
+"""
+
+import json, requests, traceback
+
+BLOCKCHAIN_API_BASE_URL = "https://blockchain.info"
+
+from .blockchain_client import BlockchainClient
+
+class BlockchainInfoClient(BlockchainClient):
+    def __init__(self, api_key=None, timeout=30):
+        self.type = 'blockchain.info'
+        self.timeout = timeout
+        if api_key:
+            self.auth = (api_key, '')
+        else:
+            self.auth = None
+
+
+def reverse_hash(hash, hex_format=True):
+    """ hash is in hex or binary format
+    """
+    if not hex_format:
+        hash = hexlify(hash)
+    return "".join(reversed([hash[i:i+2] for i in range(0, len(hash), 2)]))
+
+
+def format_unspents(unspents):
+    return [{
+        "transaction_hash": reverse_hash(s["tx_hash"]),
+        "output_index": s["tx_output_n"],
+        "value": s["value"],
+        "script_hex": s["script"],
+        "confirmations": s["confirmations"]
+        }
+        for s in unspents
+    ]
+
+def get_unspents(address, blockchain_client=BlockchainInfoClient()):
+    """ Get the spendable transaction outputs, also known as UTXOs or
+        unspent transaction outputs.
+    """
+    if not isinstance(blockchain_client, BlockchainInfoClient):
+        raise Exception('A BlockchainInfoClient object is required')
+
+    url = BLOCKCHAIN_API_BASE_URL + "/unspent?format=json&active=" + address
+
+    auth = blockchain_client.auth
+    if auth and len(auth) == 2 and isinstance(auth[0], str):
+        url = url + "&api_code=" + auth[0]
+
+    r = requests.get(url, auth=auth, timeout=blockchain_client.timeout)
+    try:
+        unspents = r.json()["unspent_outputs"]
+    except ValueError, e:
+        raise Exception('Invalid response from blockchain.info.')
+    
+    return format_unspents(unspents)
+
+
+def broadcast_transaction(hex_tx, blockchain_client=BlockchainInfoClient()):
+    """ Dispatch a raw transaction to the network.
+    """
+    url = BLOCKCHAIN_API_BASE_URL + '/pushtx'
+    payload = {'tx': hex_tx}
+    r = requests.post(url, data=payload, auth=blockchain_client.auth, timeout=blockchain_client.timeout)
+    
+    if 'submitted' in r.text.lower():
+        return {'success': True, 'tx_hash': virtualchain.tx_get_hash(hex_tx)}
+    else:
+        raise Exception('Invalid response from blockchain.info.')
+
+