SSDM-3554: Implemented storage and reading of credentials from file.

src/python/pybis/pybis.py

@@ -59,7 +59,9 @@ class OpenbisCredentialStore:
         """
         if not os.path.exists(self.store_path):
             return OpenbisCredentials()
-        # TODO Implement reading a credentials file
+        with open(self.store_path, "r") as f:
+            token = f.read()
+        return OpenbisCredentials(token)
 
     def write(self, credentials):
         """Write a credentials object to the store, overwriting any previous information.

src/python/pybis/pybis_test.py

@@ -18,4 +18,5 @@ def test_credentials_store(tmpdir):
     store = OpenbisCredentialStore(str(tmpdir))
     store.write(credentials)
     disk_credentials = store.read()
-    assert credentials.token == disk_credentials.token
\ No newline at end of file
+    assert credentials.token == disk_credentials.token
+    assert not disk_credentials.has_username_and_password()