Agent: Change ICredentialCollector interface to return Sequence

Being able to check if the ICredentialCollector returned an empty
Sequence is useful and easier than checking for an "empty" Iterable.

monkey/infection_monkey/credential_collectors/mimikatz_collector/mimikatz_credential_collector.py

@@ -1,4 +1,4 @@
-from typing import Iterable
+from typing import Sequence
 
 from infection_monkey.credential_collectors import LMHash, NTHash, Password, Username
 from infection_monkey.i_puppet.credential_collection import Credentials, ICredentialCollector
@@ -8,12 +8,12 @@ from .windows_credentials import WindowsCredentials
 
 
 class MimikatzCredentialCollector(ICredentialCollector):
-    def collect_credentials(self, options=None) -> Iterable[Credentials]:
+    def collect_credentials(self, options=None) -> Sequence[Credentials]:
         creds = pypykatz_handler.get_windows_creds()
         return MimikatzCredentialCollector._to_credentials(creds)
 
     @staticmethod
-    def _to_credentials(win_creds: Iterable[WindowsCredentials]) -> [Credentials]:
+    def _to_credentials(win_creds: Sequence[WindowsCredentials]) -> [Credentials]:
         all_creds = []
         for win_cred in win_creds:
             identities = []

monkey/infection_monkey/credential_collectors/ssh_collector/ssh_credential_collector.py

@@ -1,5 +1,5 @@
 import logging
-from typing import Dict, Iterable, List
+from typing import Dict, Iterable, Sequence
 
 from infection_monkey.credential_collectors import SSHKeypair, Username
 from infection_monkey.credential_collectors.ssh_collector import ssh_handler
@@ -17,7 +17,7 @@ class SSHCredentialCollector(ICredentialCollector):
     def __init__(self, telemetry_messenger: ITelemetryMessenger):
         self._telemetry_messenger = telemetry_messenger
 
-    def collect_credentials(self, _options=None) -> List[Credentials]:
+    def collect_credentials(self, _options=None) -> Sequence[Credentials]:
         logger.info("Started scanning for SSH credentials")
         ssh_info = ssh_handler.get_ssh_info(self._telemetry_messenger)
         logger.info("Finished scanning for SSH credentials")
@@ -25,7 +25,7 @@ class SSHCredentialCollector(ICredentialCollector):
         return SSHCredentialCollector._to_credentials(ssh_info)
 
     @staticmethod
-    def _to_credentials(ssh_info: Iterable[Dict]) -> List[Credentials]:
+    def _to_credentials(ssh_info: Iterable[Dict]) -> Sequence[Credentials]:
         ssh_credentials = []
 
         for info in ssh_info:

monkey/infection_monkey/i_puppet/credential_collection/i_credential_collector.py

@@ -1,10 +1,10 @@
 from abc import ABC, abstractmethod
-from typing import Iterable, Mapping, Optional
+from typing import Mapping, Optional, Sequence
 
 from .credentials import Credentials
 
 
 class ICredentialCollector(ABC):
     @abstractmethod
-    def collect_credentials(self, options: Optional[Mapping]) -> Iterable[Credentials]:
+    def collect_credentials(self, options: Optional[Mapping]) -> Sequence[Credentials]:
         pass

monkey/infection_monkey/puppet/puppet.py

@@ -32,7 +32,7 @@ class Puppet(IPuppet):
         credential_collector = self._plugin_registry.get_plugin(
             name, PluginType.CREDENTIAL_COLLECTOR
         )
-        return list(credential_collector.collect_credentials(options))
+        return credential_collector.collect_credentials(options)
 
     def run_pba(self, name: str, options: Dict) -> PostBreachData:
         return self._mock_puppet.run_pba(name, options)

monkey/tests/unit_tests/infection_monkey/credential_collectors/test_mimikatz_collector.py

@@ -1,4 +1,4 @@
-from typing import List
+from typing import Sequence
 
 import pytest
 
@@ -23,8 +23,8 @@ def patch_pypykatz(win_creds: [WindowsCredentials], monkeypatch):
     )
 
 
-def collect_credentials() -> List[Credentials]:
-    return list(MimikatzCredentialCollector().collect_credentials())
+def collect_credentials() -> Sequence[Credentials]:
+    return MimikatzCredentialCollector().collect_credentials()
 
 
 @pytest.mark.parametrize(