Don't let user import dash_html_components if dash not >=0.22.0

Author: rmarren1

dash_html_components/__init__.py

@@ -10,8 +10,17 @@
 
 # Module imports trigger a dash.development import, need to check this first
 if not hasattr(_dash, 'development'):
-    print("Dash was not successfully imported. Make sure you don't have a file "
-          "named \n'dash.py' in your current directory.", file=_sys.stderr)
+    print(
+        "Dash was not successfully imported. Make sure you don't have a file "
+        "named \n'dash.py' in your current directory.", file=_sys.stderr)
+    _sys.exit(1)
+
+# Must update to dash>=0.22.0 to use this version of dash-html-components
+if not hasattr(_dash.development.base_component, '_explicitize_args'):
+    print("Please update the `dash` module to >= 0.22.0 to use this "
+          "version of dash_html_components.\n"
+          "You are using version {:s}".format(_dash.version.__version__),
+          file=_sys.stderr)
     _sys.exit(1)
 
 

dash_html_components/version.py

@@ -1 +1 @@
-__version__ = '0.11.0'
+__version__ = '0.12.0'