[execution][loop] Implement output setup and writing

beat/backend/python/execution/loop.py

@@ -48,7 +48,6 @@ import json
 import zmq
 
 from ..algorithm import Algorithm
-from ..baseformat import baseformat
 from ..dataformat import DataFormat
 from ..helpers import create_inputs_from_configuration
 from ..helpers import create_outputs_from_configuration
@@ -209,6 +208,14 @@ class LoopExecutor(object):
             databases=databases,
         )
 
+        self.output_list, _ = create_outputs_from_configuration(
+            self.data,
+            self.algorithm,
+            self.prefix,
+            cache_root,
+            input_list=self.input_list,
+        )
+
         self.message_handler = message_handler
         self.message_handler.setup(self.algorithm, self.prefix)
         self.message_handler.set_executor(self)
@@ -251,6 +258,14 @@ class LoopExecutor(object):
         logger.debug("User loop has validated: {}\n{}".format(is_valid, answer))
         return is_valid, answer
 
+    def write(self):
+        """Write the loop output"""
+
+        retval = self.runner.write(self.output_list)
+
+        logger.debug("User loop wrote output: {}".format(retval))
+        return retval
+
     @property
     def address(self):
         """ Address of the message handler"""
@@ -267,3 +282,9 @@ class LoopExecutor(object):
 
         self.message_handler.join()
         self.message_handler = None
+
+    def close(self):
+        """Close all outputs"""
+
+        for output in self.output_list:
+            output.close()