add min version check for dnspython

Author: blink1073

pymongo/asynchronous/srv_resolver.py

@@ -17,9 +17,10 @@
 
 import ipaddress
 import random
+from importlib.metadata import version
 from typing import TYPE_CHECKING, Any, Optional, Union
 
-from pymongo.common import CONNECT_TIMEOUT
+from pymongo.common import CONNECT_TIMEOUT, check_for_min_version
 from pymongo.errors import ConfigurationError
 
 if TYPE_CHECKING:
@@ -32,6 +33,15 @@ def _have_dnspython() -> bool:
     try:
         import dns  # noqa: F401
 
+        dns_version = version("dnspython")
+        required_version, is_valid = check_for_min_version(dns_version, "dnspython")
+        if not is_valid:
+            raise RuntimeError(
+                f"pymongo requires dnspython>={required_version}, "
+                f"found version {dns_version}. "
+                "Install a compatible version with pip"
+            )
+
         return True
     except ImportError:
         return False
@@ -80,6 +90,8 @@ def __init__(
         srv_service_name: str,
         srv_max_hosts: int = 0,
     ):
+        # Ensure the version of dnspython is compatible.
+        _have_dnspython()
         self.__fqdn = fqdn
         self.__srv = srv_service_name
         self.__connect_timeout = connect_timeout or CONNECT_TIMEOUT

pymongo/synchronous/srv_resolver.py

@@ -17,9 +17,10 @@
 
 import ipaddress
 import random
+from importlib.metadata import version
 from typing import TYPE_CHECKING, Any, Optional, Union
 
-from pymongo.common import CONNECT_TIMEOUT
+from pymongo.common import CONNECT_TIMEOUT, check_for_min_version
 from pymongo.errors import ConfigurationError
 
 if TYPE_CHECKING:
@@ -32,6 +33,15 @@ def _have_dnspython() -> bool:
     try:
         import dns  # noqa: F401
 
+        dns_version = version("dnspython")
+        required_version, is_valid = check_for_min_version(dns_version, "dnspython")
+        if not is_valid:
+            raise RuntimeError(
+                f"pymongo requires dnspython>={required_version}, "
+                f"found version {dns_version}. "
+                "Install a compatible version with pip"
+            )
+
         return True
     except ImportError:
         return False
@@ -80,6 +90,8 @@ def __init__(
         srv_service_name: str,
         srv_max_hosts: int = 0,
     ):
+        # Ensure the version of dnspython is compatible.
+        _have_dnspython()
         self.__fqdn = fqdn
         self.__srv = srv_service_name
         self.__connect_timeout = connect_timeout or CONNECT_TIMEOUT