Merge pull request #10 from mirsazzathossain/dev

feat: Add celestial_capture function for downloading images from SkyView

Author: mirsazzathossain

rgc/utils/data.py

@@ -8,9 +8,11 @@
 __author__ = "Mir Sazzat Hossain"
 
 
+from pathlib import Path
 from typing import cast
 
 import pandas as pd
+from astroquery.skyview import SkyView
 from astroquery.vizier import Vizier
 
 
@@ -42,3 +44,33 @@ def catalog_quest(name: str, service: str = "Vizier") -> pd.DataFrame:
         return cast(pd.DataFrame, catalog[0].to_pandas())
     else:
         raise _UnsupportedServiceError()
+
+
+def celestial_capture(survey: str, ra: float, dec: float, filename: str) -> None:
+    """
+    Capture a celestial image using the SkyView service.
+
+    :param survey: The name of the survey to be used e.g. 'VLA FIRST (1.4 GHz)'.
+    :type survey: str
+
+    :param ra: The right ascension of the celestial object.
+    :type ra: float
+
+    :param dec: The declination of the celestial object.
+    :type dec: float
+
+    :param filename: The name of the file to save the image.
+    :type filename: str
+    """
+    image = SkyView.get_images(position=f"{ra}, {dec}", survey=survey, coordinates="J2000", pixels=(150, 150))[0]
+
+    comment = str(image[0].header["COMMENT"])
+    comment = comment.replace("\n", " ")
+    comment = comment.replace("\t", " ")
+
+    image[0].header.remove("comment", comment, True)
+    image[0].header.add_comment(comment)
+
+    folder_path = Path(filename).parent
+    Path(folder_path).mkdir(parents=True, exist_ok=True)
+    image.writeto(filename, overwrite=True)

tests/test_celestial_capture.py

@@ -0,0 +1,39 @@
+from unittest.mock import MagicMock, patch
+
+from rgc.utils.data import celestial_capture
+
+
+@patch("rgc.utils.data.SkyView")
+@patch("rgc.utils.data.Path")
+def test_celestial_capture(mock_path, mock_skyview):
+    # Mock SkyView.get_images method
+    mock_image = MagicMock()
+    mock_image[0].header = MagicMock()
+    mock_image[0].header.__getitem__.return_value = "Sample comment"
+    mock_image[0].header.remove = MagicMock()
+    mock_image[0].header.add_comment = MagicMock()
+    mock_image.writeto = MagicMock()
+    mock_skyview.get_images.return_value = [mock_image]
+
+    # Mock Path functionality
+    mock_path_instance = MagicMock()
+    mock_path_instance.parent = "mock_folder"
+    mock_path.return_value = mock_path_instance
+
+    # Call the function
+    celestial_capture("DSS2 Red", 10.684, 41.269, "test_image.fits")
+
+    # Verify that SkyView.get_images was called with correct parameters
+    mock_skyview.get_images.assert_called_once_with(
+        position="10.684, 41.269", survey="DSS2 Red", coordinates="J2000", pixels=(150, 150)
+    )
+
+    # Verify that image.writeto was called with correct filename
+    mock_image.writeto.assert_called_once_with("test_image.fits", overwrite=True)
+
+    # Verify Path.mkdir was called to create directories
+    mock_path_instance.mkdir.assert_called_once_with(parents=True, exist_ok=True)
+
+    # Verify header methods were called
+    mock_image[0].header.remove.assert_called_once_with("comment", "Sample comment", True)
+    mock_image[0].header.add_comment.assert_called_once_with("Sample comment")