From 364111db89a5473be9224d92845ac4d811352b9e Mon Sep 17 00:00:00 2001
From: Matthias Bisping <matthias.bisping@iqser.com>
Date: Sat, 26 Mar 2022 19:38:34 +0100
Subject: [PATCH] preprocessor refactoring

---
 .../estimator/preprocessor/preprocessor.py          | 12 ++++++------
 .../preprocessor/preprocessors/__init__.py          |  0
 .../preprocessor/preprocessors/tensor_conversion.py | 13 +++++++++++++
 test/unit_tests/preprocessor_test.py                |  6 ++++++
 4 files changed, 25 insertions(+), 6 deletions(-)
 create mode 100644 image_prediction/estimator/preprocessor/preprocessors/__init__.py
 create mode 100644 image_prediction/estimator/preprocessor/preprocessors/tensor_conversion.py

diff --git a/image_prediction/estimator/preprocessor/preprocessor.py b/image_prediction/estimator/preprocessor/preprocessor.py
index aab8f12..5f8b026 100644
--- a/image_prediction/estimator/preprocessor/preprocessor.py
+++ b/image_prediction/estimator/preprocessor/preprocessor.py
@@ -1,12 +1,12 @@
-from image_prediction.estimator.adapter.adapter import EstimatorAdapter
+import abc
 
 
-class Preprocessor:
-    def __init__(self):
+class Preprocessor(abc.ABC):
+
+    @staticmethod
+    @abc.abstractmethod
+    def preprocess(batch):
         pass
 
-    # def preprocess(self, batch):
-    #     return (map(image_to_normalized_tensor, batch))
-
     def __call__(self, batch):
         return self.preprocess(batch)
diff --git a/image_prediction/estimator/preprocessor/preprocessors/__init__.py b/image_prediction/estimator/preprocessor/preprocessors/__init__.py
new file mode 100644
index 0000000..e69de29
diff --git a/image_prediction/estimator/preprocessor/preprocessors/tensor_conversion.py b/image_prediction/estimator/preprocessor/preprocessors/tensor_conversion.py
new file mode 100644
index 0000000..f8e5943
--- /dev/null
+++ b/image_prediction/estimator/preprocessor/preprocessors/tensor_conversion.py
@@ -0,0 +1,13 @@
+from image_prediction.estimator.preprocessor.preprocessor import Preprocessor
+from image_prediction.estimator.preprocessor.utils import images_to_batch_tensor
+
+
+class BasicPreprocessor(Preprocessor):
+    """Converts images to tensors"""
+
+    @staticmethod
+    def preprocess(images):
+        return images_to_batch_tensor(images)
+
+    def __call__(self, images):
+        return self.preprocess(images)
diff --git a/test/unit_tests/preprocessor_test.py b/test/unit_tests/preprocessor_test.py
index 327e3fb..562e7e6 100644
--- a/test/unit_tests/preprocessor_test.py
+++ b/test/unit_tests/preprocessor_test.py
@@ -1,6 +1,7 @@
 import numpy as np
 from PIL import Image
 
+from image_prediction.estimator.preprocessor.preprocessors.tensor_conversion import BasicPreprocessor
 from image_prediction.estimator.preprocessor.utils import image_to_normalized_tensor, images_to_batch_tensor
 
 
@@ -18,3 +19,8 @@ def test_images_to_batch_tensor(images):
     tensor = images_to_batch_tensor(images)
     assert isinstance(tensor, np.ndarray)
     assert tensor.ndim == 4
+
+
+def test_basic_preprocessor(images):
+    tensor = BasicPreprocessor().preprocess(images)
+    assert tensor.ndim == 4