Add support for multi user in credentials file

README.rst

@@ -85,6 +85,18 @@ and ``password`` from that file as login credentials.
    { "username": "myusername", "password": "mypassword" }
 
 
+You can also provide multiple username and password tuples in a file as login credentials.
+The tuple to be used can be chosen by providing its username when calling pycaching.login(),
+e.g. pycaching.login("myusername2"). The first username and password tuple specified will be
+used as default if pycaching.login() is called without providing a username.
+
+.. code-block:: json
+
+   # sample .gc_credentials JSON file with mutiple users
+   [ { "username": "myusername1", "password": "mypassword1" },
+     { "username": "myusername2", "password": "mypassword2" } ]
+
+
 .. code-block:: python
 
     import pycaching

pycaching/geocaching.py

@@ -85,7 +85,7 @@ def login(self, username=None, password=None):
 
         if not username or not password:
             try:
-                username, password = self._load_credentials()
+                username, password = self._load_credentials(username=username)
             except FileNotFoundError as e:
                 raise LoginFailedException("Credentials file not found and "
                                            "no username and password is given.") from e
@@ -136,7 +136,7 @@ def login(self, username=None, password=None):
             raise LoginFailedException("Cannot login to the site "
                                        "(probably wrong username or password).")
 
-    def _load_credentials(self):
+    def _load_credentials(self, username=None):
         """Load credentials from file.
 
         Find credentials file in either current directory or user's home directory. If exists, load
@@ -164,7 +164,28 @@ def _load_credentials(self):
 
         # load contents
         with open(credentials_file, "r") as f:
-            credentials = json.load(f)
+            cred = json.load(f)
+            if isinstance(cred, dict):
+                if username is None:
+                    credentials = cred
+                else:
+                    if "username" in cred and cred["username"] == username:
+                        credentials = cred
+                    else:
+                        raise KeyError("User {} requested but not found in credential.".format(username))
+            elif isinstance(cred, list):
+                if username is None and len(cred) > 0:
+                    credentials = cred[0]
+                else:
+                    for c in cred:
+                        if "username" in c and c["username"] == username:
+                            credentials = c
+                            break
+                    else:
+                        raise KeyError("User {} requested but not found in credentials.".format(username))
+            else:
+                raise KeyError("Credential data type is unexpected {}".format(type(cred)))
+
             if "password" in credentials and "password_cmd" in credentials:
                 raise KeyError("Ambiguous keys. Choose either \"password\" or \"password_cmd\".")
             elif "password" in credentials:

test/test_geocaching.py

@@ -187,6 +187,8 @@ def test_logout(self):
     def test_load_credentials(self):
         filename_backup = self.gc._credentials_file
         credentials = {"username": _username, "password": _password}
+        multi_credentials = [{"username": _username+"1", "password": _password+"1"},
+                             {"username": _username+"2", "password": _password+"2"}]
         empty_valid_json = {}
         nonsense_str = b"ss{}ef"
         password_cmd = "echo {}".format(_password)
@@ -213,6 +215,59 @@ def test_load_credentials(self):
             finally:
                 os.remove(valid.name)
 
+        with self.subTest("Try to load valid credentials with username from current directory"):
+            try:
+                with NamedTemporaryFile(dir=".", delete=False) as valid:
+                    valid.write(json.dumps(credentials).encode())
+                self.gc._credentials_file = os.path.basename(valid.name)
+                username, password = self.gc._load_credentials(_username)
+                self.assertEqual(_username, username)
+                self.assertEqual(_password, password)
+            finally:
+                os.remove(valid.name)
+
+        with self.subTest("Try to load valid credentials with not existing username from current directory"):
+            try:
+                with NamedTemporaryFile(dir=".", delete=False) as valid:
+                    valid.write(json.dumps(credentials).encode())
+                self.gc._credentials_file = os.path.basename(valid.name)
+                with self.assertRaises(KeyError):
+                    username, password = self.gc._load_credentials(_username+"3")
+            finally:
+                os.remove(valid.name)
+
+        with self.subTest("Try to load valid multi credentials with default user from current directory"):
+            try:
+                with NamedTemporaryFile(dir=".", delete=False) as valid:
+                    valid.write(json.dumps(multi_credentials).encode())
+                self.gc._credentials_file = os.path.basename(valid.name)
+                username, password = self.gc._load_credentials()
+                self.assertEqual(_username+"1", username)
+                self.assertEqual(_password+"1", password)
+            finally:
+                os.remove(valid.name)
+
+        with self.subTest("Try to load valid multi credentials with user from current directory"):
+            try:
+                with NamedTemporaryFile(dir=".", delete=False) as valid:
+                    valid.write(json.dumps(multi_credentials).encode())
+                self.gc._credentials_file = os.path.basename(valid.name)
+                username, password = self.gc._load_credentials(_username+"2")
+                self.assertEqual(_username+"2", username)
+                self.assertEqual(_password+"2", password)
+            finally:
+                os.remove(valid.name)
+
+        with self.subTest("Try to load valid multi credentials with not existing user from current directory"):
+            try:
+                with NamedTemporaryFile(dir=".", delete=False) as valid:
+                    valid.write(json.dumps(multi_credentials).encode())
+                self.gc._credentials_file = os.path.basename(valid.name)
+                with self.assertRaises(KeyError):
+                    username, password = self.gc._load_credentials(_username+"3")
+            finally:
+                os.remove(valid.name)
+
         with self.subTest("Try to load empty file from current directory"):
             try:
                 with NamedTemporaryFile(dir=".", delete=False) as empty:
@@ -223,6 +278,36 @@ def test_load_credentials(self):
             finally:
                 os.remove(empty.name)
 
+        with self.subTest("Try to load very empty multi credential file from current directory"):
+            try:
+                with NamedTemporaryFile(dir=".", delete=False) as valid:
+                    valid.write(json.dumps([]).encode())
+                self.gc._credentials_file = os.path.basename(valid.name)
+                with self.assertRaises(KeyError):
+                    username, password = self.gc._load_credentials()
+            finally:
+                os.remove(valid.name)
+
+        with self.subTest("Try to load empty multi credential file from current directory"):
+            try:
+                with NamedTemporaryFile(dir=".", delete=False) as valid:
+                    valid.write(json.dumps([empty_valid_json]).encode())
+                self.gc._credentials_file = os.path.basename(valid.name)
+                with self.assertRaises(KeyError):
+                    username, password = self.gc._load_credentials()
+            finally:
+                os.remove(valid.name)
+
+        with self.subTest("Try to load multi credential file with invalid format from current directory"):
+            try:
+                with NamedTemporaryFile(dir=".", delete=False) as valid:
+                    valid.write(json.dumps("username").encode())
+                self.gc._credentials_file = os.path.basename(valid.name)
+                with self.assertRaises(KeyError):
+                    username, password = self.gc._load_credentials()
+            finally:
+                os.remove(valid.name)
+
         with self.subTest("Try to load nonsense file from current directory"):
             try:
                 with NamedTemporaryFile(dir=".", delete=False) as nonsense: