Add cache into engineservice for intermediate data.

Signed-off-by: Bofu Chen (bafu) <bofu@dt42.io>

inference/engineservice.py

@@ -41,6 +41,15 @@
 
 
 class DLEngine(object):
+    def __init__(self):
+        self.model_input_cache = []
+        self.model_output_cache = ''
+        self.cache = {
+            'model_input': [],
+            'model_output': '',
+            'model_output_filepath': ''
+        }
+
     def process_input(self, tensor):
         return tensor
 
@@ -51,9 +60,12 @@ def inference(self, tensor):
     def process_output(self, output):
         return output
 
-    def save_output(self, output, filepath):
-        with open(filepath, 'w') as f:
-            f.write(output)
+    def cache_data(self, key, value):
+        self.cache[key] = value
+
+    def save_cache(self):
+        with open(self.cache['model_output_filepath'], 'w') as f:
+            f.write(self.model_output_cache)
 
 
 class EventHandler(PatternMatchingEventHandler):
@@ -99,14 +111,17 @@ def server(self):
         while True:
             input_name = self.image_queue.get()
             image_data = cv2.imread(input_name).astype(np.float32)
+            self.cache_data('model_input', image_data)
             image_data = self.engine.process_input(image_data)
 
             output = self.engine.inference(image_data)
             model_outputs = self.engine.process_output(output)
+            self.cache_data('model_ouptut', model_outputs)
 
             output_name = input_name + '.txt'
             output_done_name = output_name + '.done'
-            self.engine.save_output(model_outputs, output_name)
+            self.cache_data('model_output_filepath', output_name)
+            self.engine.save_cache()
             self.touch(output_done_name)
             logging.debug(input_name + " classified!")