obelisk

commit ca12144acb227a3d27bdf8d54d3c49aac64df114
parent 41f60ddbf3c1206d910918959361957948d2bcc3
Author: parazyd <parazyd@dyne.org>
Date:   Wed,  7 Apr 2021 19:57:17 +0200

Implement blockchain.transaction.get

There is support for including/excluding mempool transactions.
We default to inclusive.

Diffstat:
M
electrumobelisk/protocol.py
 | 
19
++++++++++++++++++-
M
electrumobelisk/util.py
 | 
13
++++++++++++-
M
electrumobelisk/zeromq.py
 | 
21
+++++++++++++++++++++

3 files changed, 51 insertions(+), 2 deletions(-)
diff --git a/electrumobelisk/protocol.py b/electrumobelisk/protocol.py
@@ -237,7 +237,24 @@ class ElectrumProtocol(asyncio.Protocol):  # pylint: disable=R0904,R0902
         return
 
     async def blockchain_transaction_get(self, query):
-        return
+        if "params" not in query or len(query["params"]) < 1:
+            return {"error": "malformed request"}
+        tx_hash = query["params"][0]
+        verbose = query["params"][1] if len(query["params"]) > 1 else False
+
+        # _ec, rawtx = await self.bx.fetch_blockchain_transaction(tx_hash)
+        _ec, rawtx = await self.bx.fetch_mempool_transaction(tx_hash)
+        if _ec and _ec != 0:
+            self.log.debug("Got error: %s", repr(_ec))
+            return {"error": "request corrupted"}
+        if not rawtx:
+            return {"error": f"txid {tx_hash} not found"}
+
+        if verbose:
+            # TODO: Help needed
+            return {"error": "not implemented with verbose=true"}
+
+        return {"result", safe_hexlify(rawtx)}
 
     async def blockchain_transaction_get_merkle(self, query):
         if "params" not in query or len(query["params"]) != 2:
diff --git a/electrumobelisk/util.py b/electrumobelisk/util.py
@@ -41,7 +41,7 @@ def is_hex_str(text):
         return False
     try:
         b = bytes.fromhex(text)
-    except:
+    except:  # pylint: disable=W0702
         return False
     # Forbid whitespaces in text:
     if len(text) != 2 * len(b):
@@ -61,3 +61,14 @@ def is_hash256_str(text):
 def safe_hexlify(val):
     """hexlify and return a string"""
     return str(hexlify(val), "utf-8")
+
+
+def bh2u(val):
+    """
+    str with hex representation of a bytes-like object
+
+    >>> x = bytes((1, 2, 10))
+    >>> bh2u(x)
+    '01020A'
+    """
+    return val.hex()
diff --git a/electrumobelisk/zeromq.py b/electrumobelisk/zeromq.py
@@ -24,6 +24,7 @@ import zmq
 import zmq.asyncio
 
 from electrumobelisk.libbitcoin_errors import make_error_code, ErrorCode
+from electrumobelisk.util import bh2u
 
 
 def create_random_id():
@@ -276,3 +277,23 @@ class Client:
         if error_code:
             return error_code, None
         return error_code, unpack_table("32s", data)
+
+    async def fetch_blockchain_transaction(self, txid):
+        """Fetch transaction by txid (not including mempool)"""
+        command = b"blockchain.fetch_transaction2"
+        error_code, data = await self._simple_request(
+            command,
+            bytes.fromhex(txid)[::-1])
+        if error_code:
+            return error_code, None
+        return error_code, bh2u(data)
+
+    async def fetch_mempool_transaction(self, txid):
+        """Fetch transaction by txid (including mempool)"""
+        command = b"transaction_pool.fetch_transaction2"
+        error_code, data = await self._simple_request(
+            command,
+            bytes.fromhex(txid)[::-1])
+        if error_code:
+            return error_code, None
+        return error_code, bh2u(data)