use dns resolver to get account key

Author: cctdaniel

pythclient/pythclient.py

@@ -13,18 +13,18 @@
 from .solana import SolanaAccount, SolanaClient, SolanaPublicKey, SOLANA_DEVNET_HTTP_ENDPOINT, SOLANA_DEVNET_WS_ENDPOINT, SolanaPublicKeyOrStr
 from .pythaccounts import PythAccount, PythMappingAccount, PythProductAccount, PythPriceAccount
 from . import exceptions, config, ratelimit
+from .utils import get_key
 
-V1_FIRST_MAPPING_ACCOUNT_KEY = "ArppEFcsybCLE8CRtQJLQ9tLv2peGmQoKWFuiUWm4KBP"
-V2_FIRST_MAPPING_ACCOUNT_KEY = "BmA9Z6FjioHJPpjT39QazZyhDRUdZy2ezwx4GiDdE2u2"
-V2_PROGRAM_KEY = "gSbePebfvPy7tRqimPoVecS2UsBvYv46ynrzWocc92s"
+V2_FIRST_MAPPING_ACCOUNT_KEY = get_key("devnet", "mapping")
+V2_PROGRAM_KEY = get_key("devnet", "program")
 
 
 class PythClient:
     def __init__(self, *,
                  solana_client: Optional[SolanaClient] = None,
                  solana_endpoint: str = SOLANA_DEVNET_HTTP_ENDPOINT,
                  solana_ws_endpoint: str = SOLANA_DEVNET_WS_ENDPOINT,
-                 first_mapping_account_key: str = V1_FIRST_MAPPING_ACCOUNT_KEY,
+                 first_mapping_account_key: str = V2_FIRST_MAPPING_ACCOUNT_KEY,
                  program_key: Optional[str] = None,
                  aiohttp_client_session: Optional[aiohttp.ClientSession] = None) -> None:
         self._first_mapping_account_key = SolanaPublicKey(first_mapping_account_key)

pythclient/utils.py

@@ -0,0 +1,33 @@
+import ast
+import dns.resolver
+from loguru import logger
+from typing import Optional
+
+DEFAULT_VERSION = "v2"
+
+
+def get_key(network: str, type: str, version: str = DEFAULT_VERSION) -> Optional[str]:
+    """
+    Get the program or mapping keys from dns TXT records.
+
+    Example dns records:
+
+        devnet-program-v2.pyth.network
+        mainnet-program-v2.pyth.network
+        testnet-mapping-v2.pyth.network
+    """
+    url = f"{network}-{type}-{version}.pyth.network"
+    try:
+        answer = dns.resolver.resolve(url, "TXT")
+    except dns.resolver.NXDOMAIN:
+        logger.error("TXT record for {} not found", url)
+        return ""
+    if len(answer) != 1:
+        logger.error("Invalid number of records returned for {}!", url)
+        return ""
+    # Example of the raw_key:
+    #     "program=FsJ3A3u2vn5cTVofAjvy6y5kwABJAqYWpe4975bi2epH"
+    raw_key = ast.literal_eval(list(answer)[0].to_text())
+    # program=FsJ3A3u2vn5cTVofAjvy6y5kwABJAqYWpe4975bi2epH"
+    _, key = raw_key.split("=", 1)
+    return key