refactor is_accumulator_update (#41)

* refactor is_accumulator_update

* bump

* add return type

Author: cctdaniel

pythclient/price_feeds.py

@@ -390,9 +390,25 @@ def parse_price_attestation(bytes_):
     }
 
 
+def is_accumulator_update(vaa, encoding=DEFAULT_VAA_ENCODING) -> bool:
+    """
+    This function checks if a given VAA is an accumulator update.
+
+    Parameters:
+    vaa (str): The VAA to check.
+    encoding (str, optional): The encoding of the VAA. Defaults to hex.
+
+    Returns:
+    bool: True if the VAA is an accumulator update, False otherwise.
+    """
+    if encode_vaa_for_chain(vaa, encoding, buffer=True)[:4].hex() == ACCUMULATOR_MAGIC:
+        return True
+    return False
+
+
 # Referenced from https://github.com/pyth-network/pyth-crosschain/blob/110caed6be3be7885773d2f6070b143cc13fb0ee/price_service/server/src/rest.ts#L139
 def vaa_to_price_infos(vaa, encoding=DEFAULT_VAA_ENCODING) -> List[PriceInfo]:
-    if encode_vaa_for_chain(vaa, encoding, buffer=True)[:4].hex() == ACCUMULATOR_MAGIC:
+    if is_accumulator_update(vaa, encoding):
         return extract_price_info_from_accumulator_update(vaa, encoding)
     parsed_vaa = parse_vaa(vaa, encoding)
     batch_attestation = parse_batch_price_attestation(parsed_vaa["payload"])

setup.py

@@ -7,7 +7,7 @@
 
 setup(
     name='pythclient',
-    version='0.1.13',
+    version='0.1.14',
     packages=['pythclient'],
     author='Pyth Developers',
     author_email='[email protected]',

tests/test_price_feeds.py

@@ -6,6 +6,7 @@
     MerkleUpdate,
     compress_accumulator_update,
     encode_vaa_for_chain,
+    is_accumulator_update,
     parse_accumulator_update,
     serialize_accumulator_update,
     vaa_to_price_info,
@@ -36,6 +37,13 @@
 ACCUMULATOR_UPDATE_DATA_SOL_DIFFERENT_VAA = "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"
 
 
+def test_is_accumulator_update():
+    # Test that a price service VAA is not an accumulator update
+    assert is_accumulator_update(HEX_VAA, "hex") == False
+    # Test that an accumulator update VAA is an accumulator update
+    assert is_accumulator_update(ACCUMULATOR_UPDATE_DATA_BTC_SAME_VAA, "base64") == True
+
+
 def test_valid_hex_vaa_to_price_info():
     price_info = vaa_to_price_info(BTC_ID, HEX_VAA)
     assert price_info.seq_num == 558149954