Add unittests for writing IDs to metadata. The test for mpl still fails as...

Add unittests for writing IDs to metadata. The test for mpl still fails as writing metadata with mpl is still not resolved.

plotid/publish.py

@@ -110,7 +110,7 @@ class PublishOptions:
 
         """
         # Export plot figure to picture.
-        plot_paths = save_plot(self.figure, self.plot_names)
+        plot_paths = save_plot(self.figure, self.plot_names, figure_ids=self.figure_ids)
         match self.data_storage:
             case "centralized":
                 self.centralized_data_storage()

plotid/save_plot.py

@@ -12,7 +12,7 @@ import matplotlib
 import matplotlib.pyplot as plt
 
 
-def save_plot(figures, plot_names, extension="png"):
+def save_plot(figures, plot_names, figure_ids=[], extension="png"):
     """
     Export plot(s).
 
@@ -22,8 +22,10 @@ def save_plot(figures, plot_names, extension="png"):
         Figure that was tagged and now should be saved as picture.
     plot_name : str or list of str
         Names of the files where the plots will be saved to.
-    extension : str
-        File extension for the plot export.
+    figure_ids: str or list of str, optional
+        IDs of the figures that will be added to the metadata of the exported images.
+    extension : str, optional
+        File extension for the plot export. Default is png.
 
     Returns
     -------
@@ -71,7 +73,7 @@ def save_plot(figures, plot_names, extension="png"):
         elif all(x in str(type(fig)) for x in ["PIL", "ImageFile"]):
             plot_path.append(plot_names[i] + ".tmp." + extension)
             img_exif = fig.getexif()
-            img_exif[270] = "Identiplier2"
+            img_exif[270] = figure_ids[i]
             fig.save(plot_path[i], exif=img_exif)
         else:
             raise TypeError(f"Figure number {i} is not a valid figure object.")

tests/test_save_plot.py

@@ -14,6 +14,7 @@ FIGURE = plt.figure()
 PLOT_NAME = "PLOT_NAME"
 IMG1 = "image1.png"
 IMG2 = "image2.jpg"
+IDS = ["ID0", "ID1", "ID2"]
 
 
 class TestSavePlot(unittest.TestCase):
@@ -27,44 +28,57 @@ class TestSavePlot(unittest.TestCase):
 
     def test_save_plot_matplotlib(self):
         """
-        Test if save_plot succeeds with valid arguments
-        using the matplotlib engine.
+        Test if save_plot succeeds with valid arguments using the matplotlib engine.
+        Check if ID was NOT set in metadata.
         """
         plot_paths = save_plot(FIGURE, [PLOT_NAME], extension="jpg")
         self.assertIsInstance(plot_paths, list)
+        img_exif = Image.open(plot_paths[0]).getexif()
+        assert 270 not in img_exif
         os.remove(PLOT_NAME + ".tmp.jpg")
 
     def test_save_plot_image_png(self):
         """
         Test if save_plot succeeds with valid arguments using the image engine
-        and a png file.
+        and a png file. Check if IDs are in metadata.
         """
         img1 = Image.open(IMG1)
-        plot_paths = save_plot(img1, [PLOT_NAME])
+        plot_paths = save_plot(img1, [PLOT_NAME], figure_ids=[IDS[1]])
         self.assertIsInstance(plot_paths, list)
+        img_exif = Image.open(plot_paths[0]).getexif()
+        assert img_exif[270] == IDS[1]
         os.remove(PLOT_NAME + ".tmp.png")
 
     def test_save_plot_image_jpg(self):
         """
         Test if save_plot succeeds with valid arguments using the image engine
-        and a list of jpg files.
+        and a list of jpg files. Check if IDs are in metadata.
         """
         img2 = Image.open(IMG2)
         imgs_as_list = [img2, img2]
-        plot_paths = save_plot(imgs_as_list, [PLOT_NAME], extension="jpg")
+        plot_paths = save_plot(
+            imgs_as_list, [PLOT_NAME], extension="jpg", figure_ids=IDS[0:2]
+        )
         self.assertIsInstance(plot_paths, list)
-        os.remove(PLOT_NAME + "1.tmp.jpg")
-        os.remove(PLOT_NAME + "2.tmp.jpg")
+        for i in (1, 2):
+            img_exif = Image.open(plot_paths[i - 1]).getexif()
+            assert img_exif[270] == IDS[i - 1]
+            os.remove(PLOT_NAME + f"{i}.tmp.jpg")
 
     def test_more_figs_than_names(self):
         """
         Test if a warning is raised if more figures than plot names are given.
-        Additionally, check if files are named correctly.
+        Additionally, check if files are named correctly and IDs are set in exif
+        metadata.
         """
         with self.assertWarns(Warning):
-            save_plot([FIGURE, FIGURE, FIGURE], [PLOT_NAME])
+            plot_paths = save_plot(
+                [FIGURE, FIGURE, FIGURE], [PLOT_NAME], figure_ids=IDS
+            )
         for i in (1, 2, 3):
             assert os.path.isfile(PLOT_NAME + f"{i}.tmp.png")
+            img_exif = Image.open(plot_paths[i]).getexif()
+            assert img_exif[270] == IDS[i - 1]
             os.remove(PLOT_NAME + f"{i}.tmp.png")
 
     def test_more_names_than_figs(self):