Fix issues exporting various image and chart formats. (#42)

Author: bbassett-tibco

spotfire/sbdf.pyx

@@ -1177,7 +1177,7 @@ cdef _export_obj_matplotlib_figure(obj, default_column_name):
     cdef np_c.ndarray values
 
     context = _ExportContext()
-    context.set_valuetype(sbdf_c.sbdf_vt_binary())
+    context.set_valuetype_id(sbdf_c.SBDF_BINARYTYPEID)
     with io.BytesIO() as buf:
         obj.set_canvas(matplotlib.pyplot.gcf().canvas)
         obj.savefig(buf, format="png")
@@ -1198,7 +1198,7 @@ cdef _export_obj_seaborn_grid(obj, default_column_name):
     cdef np_c.ndarray values
 
     context = _ExportContext()
-    context.set_valuetype(sbdf_c.sbdf_vt_binary())
+    context.set_valuetype_id(sbdf_c.SBDF_BINARYTYPEID)
     with io.BytesIO() as buf:
         obj.savefig(buf)
         values = np.array([buf.getvalue()], dtype='object')
@@ -1218,9 +1218,9 @@ cdef _export_obj_pil_image(obj, default_column_name):
     cdef np_c.ndarray values
 
     context = _ExportContext()
-    context.set_valuetype(sbdf_c.sbdf_vt_binary())
+    context.set_valuetype_id(sbdf_c.SBDF_BINARYTYPEID)
     with io.BytesIO() as buf:
-        obj.save(buf)
+        obj.save(buf, format="png")
         values = np.array([buf.getvalue()], dtype='object')
         context.set_arrays(values, [False])
 

spotfire/test/test_sbdf.py

@@ -9,6 +9,9 @@
 import pandas
 import pandas.testing
 import geopandas
+import matplotlib.pyplot
+import seaborn
+import PIL.Image
 
 import spotfire
 from spotfire import sbdf
@@ -413,3 +416,43 @@ def test_non_str_column_name(self):
             df2 = sbdf.import_data(f"{tempdir}/output.sbdf")
             for i, col in enumerate(df2.columns):
                 self.assertEqual(type(col), str, f"df2.columns[{i}] = {repr(col)}")
+
+    def test_image_matplot(self):
+        """Verify Matplotlib figures export properly"""
+        matplotlib.pyplot.clf()
+        fig, _ = matplotlib.pyplot.subplots()
+        with tempfile.TemporaryDirectory() as tempdir:
+            sbdf.export_data(fig, f"{tempdir}/output.sbdf")
+            df2 = sbdf.import_data(f"{tempdir}/output.sbdf")
+            self.assertEqual(len(df2), 1)
+            self.assertEqual(len(df2.columns), 1)
+            self.assertEqual(df2.columns[0], 'x')
+            val = df2.at[0, "x"]
+            self.assertEqual(val[0:8], b'\x89PNG\x0d\x0a\x1a\x0a')
+
+    def test_image_seaborn(self):
+        """Verify Seaborn grids export properly"""
+        matplotlib.pyplot.clf()
+        dataframe = pandas.DataFrame({'x': range(10), 'y': range(10, 0, -1)})
+        grid = seaborn.FacetGrid(dataframe)
+        with tempfile.TemporaryDirectory() as tempdir:
+            sbdf.export_data(grid, f"{tempdir}/output.sbdf")
+            df2 = sbdf.import_data(f"{tempdir}/output.sbdf")
+            self.assertEqual(len(df2), 1)
+            self.assertEqual(len(df2.columns), 1)
+            self.assertEqual(df2.columns[0], 'x')
+            val = df2.at[0, "x"]
+            self.assertEqual(val[0:8], b'\x89PNG\x0d\x0a\x1a\x0a')
+
+    def test_image_pil(self):
+        """Verify PIL images export properly"""
+        image = PIL.Image.new("RGB", (100, 100))
+        with tempfile.TemporaryDirectory() as tempdir:
+            sbdf.export_data(image, f"{tempdir}/output.sbdf")
+            df2 = sbdf.import_data(f"{tempdir}/output.sbdf")
+            val = df2.at[0, "x"]
+            self.assertEqual(len(df2), 1)
+            self.assertEqual(len(df2.columns), 1)
+            self.assertEqual(df2.columns[0], 'x')
+            val = df2.at[0, "x"]
+            self.assertEqual(val[0:8], b'\x89PNG\x0d\x0a\x1a\x0a')