docs(document): support readthedocs

.gitignore

@@ -7,3 +7,5 @@
 docs/_build/
 docs/_templates/
 examples/**/*.db
+
+dist/

README.rst

@@ -25,7 +25,7 @@ Flask-Identity
 A lightweight extension & library to security Flask applications quickly and simply.
 
 About Flask-Identity
-------------------
+--------------------
 
 Flask-Identity allows you to quickly add common security mechanisms to your
 Flask application. They include:

docs/configuration.rst

@@ -71,6 +71,18 @@ These configuration are used globally across all features and should be configur
 
     Default: ``'_next'``.
 
+.. py:data:: HASH_SALT
+
+    Specifies the HMAC salt. This is required for all schemes that
+    are configured for double hashing. A good salt can be generated using:
+    ``secrets.SystemRandom().getrandbits(128)``.
+
+    If this value is ``None`` (the default), then will use ``SECRET_KEY`` as salt to encrypt hash.
+
+    Strongly recommend set it to a different value for more security.
+
+    Defaults to ``None``.
+
 .. py:data:: TOKEN_SALT
 
     The salt used to encrypt session, request or cookie token.

flask_identity/config.py

@@ -53,6 +53,12 @@
     #: Default: ``'_next'``.
     'NEXT_KEY': '_next',
 
+    #: Specifies the HMAC salt. This is required for all schemes that
+    #: are configured for double hashing. A good salt can be generated using:
+    #: ``secrets.SystemRandom().getrandbits(128)``.
+    #: Defaults to ``None``.
+    'HASH_SALT': None,
+
     #: The salt used to encrypt session, request or cookie token.
     #: If this value is ``None`` (the default), then will use ``SECRET_KEY`` as salt
     #: to encrypt token.