[enh] Reallow to print result in json and readd compatibility for apps

bin/yunohost

@@ -2,7 +2,7 @@
 # -*- coding: utf-8 -*-
 
 import sys
-import os.path
+import os
 
 from_source = False
 
@@ -23,10 +23,18 @@ if __name__ == '__main__':
     init(_from_source=from_source)
 
     # Additional arguments
-    use_cache = True
+    cache = True
+    json = False
     if '--no-cache' in sys.argv:
-        use_cache = False
+        cache = False
         sys.argv.remove('--no-cache')
+    if '--json' in sys.argv:
+        json = True
+        sys.argv.remove('--json')
+
+    ## Compatibility with previous moulinette
+    if not os.isatty(1):
+        json = True
 
     args = list(sys.argv)
     args.pop(0)
@@ -46,5 +54,5 @@ if __name__ == '__main__':
         sys.exit(1)
 
     # Execute the action
-    ret = cli(['yunohost'], args, use_cache)
+    ret = cli(['yunohost'], args, print_json=json, use_cache=cache)
     sys.exit(ret)