ignore_errors parameter supported in shell plugin

platypush/plugins/shell/__init__.py

@@ -9,13 +9,14 @@ class ShellPlugin(Plugin):
     """
 
     @action
-    def exec(self, cmd):
+    def exec(self, cmd, ignore_errors=False):
         """
         Execute a command.
 
         :param cmd: Command to execute
         :type cmd: str
 
+        :param ignore_errors: If set, then any errors in the command execution will be ignored. Otherwise a RuntimeError will be thrown (default value: False)
         :returns: A response object where the ``output`` field will contain the command output as a string, and the ``errors`` field will contain whatever was sent to stderr.
         """
 
@@ -23,6 +24,10 @@ class ShellPlugin(Plugin):
             return subprocess.check_output(
                 cmd, stderr=subprocess.STDOUT, shell=True).decode('utf-8')
         except subprocess.CalledProcessError as e:
+            if ignore_errors:
+                self.logger.warning('Command {} failed with error: {}'.format(
+                    cmd, e.output.decode('utf-8')))
+            else:
                 raise RuntimeError(e.output.decode('utf-8'))