estimate timestamps instead of using block headers

lbry/extras/daemon/json_response_encoder.py

@@ -159,7 +159,6 @@ class JSONResponseEncoder(JSONEncoder):
             return
         tx_height = txo.tx_ref.height
         best_height = self.ledger.headers.height
-        timestamp = self.ledger.headers.synchronous_get(tx_height)['timestamp'] if 0 < tx_height <= best_height else None
         output = {
             'txid': txo.tx_ref.id,
             'nout': txo.position,
@@ -167,7 +166,7 @@ class JSONResponseEncoder(JSONEncoder):
             'amount': dewies_to_lbc(txo.amount),
             'address': txo.get_address(self.ledger) if txo.has_address else None,
             'confirmations': (best_height+1) - tx_height if tx_height > 0 else tx_height,
-            'timestamp': timestamp
+            'timestamp': self.ledger.headers.estimated_timestamp(tx_height)
         }
         if txo.is_spent is not None:
             output['is_spent'] = txo.is_spent
@@ -245,7 +244,7 @@ class JSONResponseEncoder(JSONEncoder):
                 if isinstance(value, int):
                     meta[key] = dewies_to_lbc(value)
         if 0 < meta.get('creation_height', 0) <= self.ledger.headers.height:
-            meta['creation_timestamp'] = self.ledger.headers.synchronous_get(meta['creation_height'])['timestamp']
+            meta['creation_timestamp'] = self.ledger.headers.estimated_timestamp(meta['creation_height'])
         return meta
 
     def encode_input(self, txi):
@@ -307,7 +306,7 @@ class JSONResponseEncoder(JSONEncoder):
             'added_on': managed_stream.added_on,
             'height': tx_height,
             'confirmations': (best_height + 1) - tx_height if tx_height > 0 else tx_height,
-            'timestamp': self.ledger.headers.synchronous_get(tx_height)['timestamp'] if 0 < tx_height <= best_height else None,
+            'timestamp': self.ledger.headers.estimated_timestamp(tx_height),
             'is_fully_reflected': managed_stream.is_fully_reflected
         }
 

lbry/stream/stream_manager.py

@@ -338,7 +338,7 @@ class StreamManager:
                     'claim_sequence': -1,
                     'address': txo.get_address(wallet_manager.ledger),
                     'valid_at_height': txo.meta.get('activation_height', None),
-                    'timestamp': wallet_manager.ledger.headers.synchronous_get(tx_height)['timestamp'],
+                    'timestamp': wallet_manager.ledger.headers.estimated_timestamp(tx_height),
                     'supports': []
                 }
             else:

lbry/wallet/header.py

@@ -33,6 +33,8 @@ class Headers:
     genesis_hash = b'9c89283ba0f3227f6c03b70216b9f665f0118d5e0fa729cedf4fb34d6a34f463'
     target_timespan = 150
     checkpoint = (600_000, b'100b33ca3d0b86a48f0d6d6f30458a130ecb89d5affefe4afccb134d5a40f4c2')
+    first_block_timestamp = 1466646588  # block 1, as 0 is off by a lot
+    timestamp_average_offset = 160.6855883050695  # calculated at 733447
 
     validate_difficulty: bool = True
 
@@ -111,12 +113,8 @@ class Headers:
             raise IndexError(f"{height} is out of bounds, current height: {self.height}")
         return self.deserialize(height, self.get_raw_header(height))
 
-    def synchronous_get(self, height):
-        if isinstance(height, slice):
-            raise NotImplementedError("Slicing of header chain has not been implemented yet.")
-        if not 0 <= height <= self.height:
-            raise IndexError(f"{height} is out of bounds, current height: {self.height}")
-        return self.deserialize(height, self.get_raw_header(height))
+    def estimated_timestamp(self, height):
+        return self.first_block_timestamp + (height * self.timestamp_average_offset)
 
     def get_raw_header(self, height) -> bytes:
         self.io.seek(height * self.header_size, os.SEEK_SET)
@@ -283,10 +281,6 @@ class Headers:
             header = headers[start:end]
             yield self.hash_header(header), self.deserialize(height+idx, header)
 
-    @property
-    def claim_trie_root(self):
-        return self[self.height]['claim_trie_root']
-
     @staticmethod
     def header_hash_to_pow_hash(header_hash: bytes):
         header_hash_bytes = unhexlify(header_hash)[::-1]

lbry/wallet/ledger.py

@@ -899,7 +899,7 @@ class Ledger(metaclass=LedgerRegistry):
         headers = self.headers
         history = []
         for tx in txs:  # pylint: disable=too-many-nested-blocks
-            ts = headers.synchronous_get(tx.height)['timestamp'] if tx.height > 0 else None
+            ts = headers.estimated_timestamp(tx.height)['timestamp']
             item = {
                 'txid': tx.id,
                 'timestamp': ts,

tests/integration/blockchain/test_resolve_command.py

@@ -49,11 +49,11 @@ class ResolveCommand(BaseResolveTestCase):
         self.assertTrue(claim['is_channel_signature_valid'])
         self.assertEqual(
             claim['timestamp'],
-            self.ledger.headers.synchronous_get(claim['height'])['timestamp']
+            self.ledger.headers.estimated_timestamp(claim['height'])
         )
         self.assertEqual(
             claim['signing_channel']['timestamp'],
-            self.ledger.headers.synchronous_get(claim['signing_channel']['height'])['timestamp']
+            self.ledger.headers.estimated_timestamp(claim['signing_channel']['height'])
         )
 
         # resolving claim foo by itself

tests/unit/stream/test_stream_manager.py

@@ -84,6 +84,9 @@ async def get_mock_wallet(sd_hash, storage, balance=10.0, fee=None):
     })
 
     class FakeHeaders:
+        def estimated_timestamp(self, height):
+            return 1984
+
         def __init__(self, height):
             self.height = height