[SYNPY-1282] Adds Type Hinting to client.py (#987)

Adds type hints to several functions in `client.py` and a quick note to CONTRIBUTING.md because of an issue getting the `pipenv install` to work properly.

CONTRIBUTING.md

@@ -59,6 +59,7 @@ Perform the following one-time steps to set up your local environment.
 1. This package uses Python, if you have not already, please install [pyenv](https://github.com/pyenv/pyenv#installation) to manage your Python versions. Versions supported by this package are all versions >=3.8 and <=3.11. If you do not install `pyenv` make sure that Python and `pip` are installed correctly and have been added to your PATH by running `python3 --version` and `pip3 --version`. If your installation was successful, your terminal will return the versions of Python and `pip` that you installed.  **Note**: If you have `pyenv` it will install a specific version of Python for you.
 
 2. Install `pipenv` by running `pip install pipenv`.
+    - If you already have `pipenv` installed, ensure that the version is >=2023.9.8 to avoid compatibility issues.
 
 3. Install `synapseclient` locally using pipenv:
 

synapseclient/client.py

@@ -221,16 +221,16 @@ class Synapse(object):
     # TODO: add additional boolean for write to disk?
     def __init__(
         self,
-        repoEndpoint=None,
-        authEndpoint=None,
-        fileHandleEndpoint=None,
-        portalEndpoint=None,
-        debug=None,
-        skip_checks=False,
-        configPath=CONFIG_FILE,
-        requests_session=None,
-        cache_root_dir=None,
-        silent=None,
+        repoEndpoint: str = None,
+        authEndpoint: str = None,
+        fileHandleEndpoint: str = None,
+        portalEndpoint: str = None,
+        debug: bool = None,
+        skip_checks: bool = False,
+        configPath: str = CONFIG_FILE,
+        requests_session: requests.Session = None,
+        cache_root_dir: str = None,
+        silent: bool = None,
     ):
         self._requests_session = requests_session or requests.Session()
 
@@ -296,20 +296,20 @@ def _init_logger(self):
         logging.getLogger("py.warnings").handlers = self.logger.handlers
 
     @property
-    def max_threads(self):
+    def max_threads(self) -> int:
         return self._max_threads
 
     @max_threads.setter
     def max_threads(self, value: int):
         self._max_threads = min(max(value, 1), MAX_THREADS_CAP)
 
     @property
-    def username(self):
+    def username(self) -> Union[str, None]:
         # for backwards compatability when username was a part of the Synapse object and not in credentials
         return self.credentials.username if self.credentials is not None else None
 
     @functools.lru_cache()
-    def getConfigFile(self, configPath):
+    def getConfigFile(self, configPath: str) -> configparser.RawConfigParser:
         """
         Retrieves the client configuration information.
 
@@ -328,11 +328,11 @@ def getConfigFile(self, configPath):
 
     def setEndpoints(
         self,
-        repoEndpoint=None,
-        authEndpoint=None,
-        fileHandleEndpoint=None,
-        portalEndpoint=None,
-        skip_checks=False,
+        repoEndpoint: str = None,
+        authEndpoint: str = None,
+        fileHandleEndpoint: str = None,
+        portalEndpoint: str = None,
+        skip_checks: bool = False,
     ):
         """
         Sets the locations for each of the Synapse services (mostly useful for testing).
@@ -385,14 +385,14 @@ def setEndpoints(
 
     def login(
         self,
-        email=None,
-        password=None,
-        apiKey=None,
-        sessionToken=None,
-        rememberMe=False,
-        silent=False,
-        forced=False,
-        authToken=None,
+        email: str = None,
+        password: str = None,
+        apiKey: str = None,
+        sessionToken: str = None,
+        rememberMe: bool = False,
+        silent: bool = False,
+        forced: bool = False,
+        authToken: str = None,
     ):
         """
         Valid combinations of login() arguments:
@@ -508,26 +508,26 @@ def login(
                 )
             )
 
-    def _get_config_section_dict(self, section_name):
+    def _get_config_section_dict(self, section_name: str) -> dict:
         config = self.getConfigFile(self.configPath)
         try:
             return dict(config.items(section_name))
         except configparser.NoSectionError:
             # section not present
             return {}
 
-    def _get_config_authentication(self):
+    def _get_config_authentication(self) -> str:
         return self._get_config_section_dict(
             config_file_constants.AUTHENTICATION_SECTION_NAME
         )
 
-    def _get_client_authenticated_s3_profile(self, endpoint, bucket):
+    def _get_client_authenticated_s3_profile(self, endpoint: str, bucket: str) -> str:
         config_section = endpoint + "/" + bucket
         return self._get_config_section_dict(config_section).get(
             "profile_name", "default"
         )
 
-    def _get_transfer_config(self):
+    def _get_transfer_config(self) -> dict:
         # defaults
         transfer_config = {"max_threads": DEFAULT_NUM_THREADS, "use_boto_sts": False}
 
@@ -552,7 +552,7 @@ def _get_transfer_config(self):
 
         return transfer_config
 
-    def _getSessionToken(self, email, password):
+    def _getSessionToken(self, email: str, password: str) -> str:
         """Returns a validated session token."""
         try:
             req = {"email": email, "password": password}
@@ -572,7 +572,7 @@ def _getSessionToken(self, email, password):
                 raise SynapseAuthenticationError("Invalid username or password.")
             raise
 
-    def _getAPIKey(self, sessionToken):
+    def _getAPIKey(self, sessionToken: str) -> str:
         """Uses a session token to fetch an API key."""
 
         headers = {"sessionToken": sessionToken, "Accept": "application/json"}
@@ -591,7 +591,7 @@ def _is_logged_in(self) -> bool:
             return False
         return True
 
-    def logout(self, forgetMe=False):
+    def logout(self, forgetMe: bool = False):
         """
         Removes authentication information from the Synapse client.
 
@@ -654,7 +654,7 @@ def getUserProfile(
             )
         )
 
-    def _findPrincipals(self, query_string):
+    def _findPrincipals(self, query_string: str) -> typing.List[UserGroupHeader]:
         """
         Find users or groups by name or email.