Add SUPERSET_HOME environment variable

docs/faq.rst

@@ -126,13 +126,13 @@ be applied, it's as simple as that.
 
 Why does fabmanager or superset freezed/hung/not responding when started (my home directory is NFS mounted)?
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-superset creates and uses an sqlite database at ``~/.superset/superset.db``. Sqlite is known to `don't work well if used on NFS`__ due to broken file locking implementation on NFS.
+By default, superset creates and uses an sqlite database at ``~/.superset/superset.db``. Sqlite is known to `don't work well if used on NFS`__ due to broken file locking implementation on NFS.
 
 __ https://www.sqlite.org/lockingv3.html
 
-One work around is to create a symlink from ~/.superset to a directory located on a non-NFS partition.
+You can override this path using the ``SUPERSET_HOME`` environment variable.
 
-Another work around is to change where superset stores the sqlite database by adding ``SQLALCHEMY_DATABASE_URI = 'sqlite:////new/localtion/superset.db'`` in superset_config.py (create the file if needed), then adding the directory where superset_config.py lives to PYTHONPATH environment variable (e.g. ``export PYTHONPATH=/opt/logs/sandbox/airbnb/``).
+Another work around is to change where superset stores the sqlite database by adding ``SQLALCHEMY_DATABASE_URI = 'sqlite:////new/location/superset.db'`` in superset_config.py (create the file if needed), then adding the directory where superset_config.py lives to PYTHONPATH environment variable (e.g. ``export PYTHONPATH=/opt/logs/sandbox/airbnb/``).
 
 How do I add new columns to an existing table
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superset/config.py

@@ -24,7 +24,10 @@
 STATS_LOGGER = DummyStatsLogger()
 
 BASE_DIR = os.path.abspath(os.path.dirname(__file__))
-DATA_DIR = os.path.join(os.path.expanduser('~'), '.superset')
+if 'SUPERSET_HOME' in os.environ:
+    DATA_DIR = os.environ['SUPERSET_HOME']
+else:
+    DATA_DIR = os.path.join(os.path.expanduser('~'), '.superset')
 if not os.path.exists(DATA_DIR):
     os.makedirs(DATA_DIR)