Minimize HipsTile classs functionality

hips/tiles/tests/test_tile.py

@@ -1,61 +1,34 @@
 # Licensed under a 3-clause BSD style license - see LICENSE.rst
-from astropy.utils.data import get_pkg_data_filename
 from astropy.tests.helper import remote_data
-from ..description import HipsDescription
 from ..tile import HipsTile
-from pathlib import Path
-import numpy as np
 
-class TestHipsTile:
-    @classmethod
-    def setup_class(cls):
-        filename = get_pkg_data_filename('data/properties.txt')
-        hips_description = HipsDescription.read(filename)
-
-        cls.fits_tile = HipsTile(hips_description=hips_description, order=6,
-                            ipix=30889, format='fits', tile_width=512)
-        cls.jpg_tile = HipsTile(hips_description=hips_description, order=6,
-                            ipix=30889, format='jpg', tile_width=512)
-        cls.fits_tile.base_url = 'http://alasky.unistra.fr/2MASS/H'
-        cls.jpg_tile.base_url = 'http://alasky.unistra.fr/2MASS/H'
-
-    def test_base_url(self):
-        assert self.fits_tile.base_url == 'http://alasky.unistra.fr/2MASS/H'
-        assert self.jpg_tile.base_url == 'http://alasky.unistra.fr/2MASS/H'
-
-    def test_tile_url(self):
-        assert self.fits_tile.tile_url == 'http://alasky.unistra.fr/2MASS/H/Norder6/Dir30000/Npix30889.fits'
-        assert self.jpg_tile.tile_url == 'http://alasky.unistra.fr/2MASS/H/Norder6/Dir30000/Npix30889.jpg'
-
-    @remote_data
-    def test_fetch(self):
-        self.fits_tile.fetch()
-        self.jpg_tile.fetch()
-
-        shape_fits_precomp = (512, 512)
-        shape_jpg_precomp = (512, 512, 3)
-        data_precomp = [0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1]
-        assert self.fits_tile.data.shape == shape_fits_precomp
-        assert self.jpg_tile.data.shape == shape_jpg_precomp
-        assert list(self.fits_tile.data[510][:12]) == data_precomp
-
-    def test_read(self):
-        self.fits_tile.read()
-        self.jpg_tile.read()
-
-        shape_fits_precomp = (512, 512)
-        shape_jpg_precomp = (512, 512, 3)
-        data_precomp = [0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1]
-        assert (self.fits_tile.data.shape) == shape_fits_precomp
-        assert (self.jpg_tile.data.shape) == shape_jpg_precomp
-        assert list(self.fits_tile.data[510][:12]) == data_precomp
-
-    def test_write(self):
-        filename = 'test_file'
-        self.fits_tile.write(filename)
-        self.jpg_tile.write(filename)
-
-        path_fits = self.fits_tile.path.joinpath(''.join([filename, '.', self.fits_tile.format]))
-        path_jpg = self.jpg_tile.path.joinpath(''.join([filename, '.', self.jpg_tile.format]))
-        assert True == path_fits.is_file()
-        assert True == path_jpg.is_file()
+@remote_data
+def test_fetch():
+    fits_tile = HipsTile.fetch('fits', 'http://alasky.unistra.fr/2MASS/H/Norder6/Dir30000/Npix30889.fits')
+    jpg_tile = HipsTile.fetch('jpg', 'http://alasky.unistra.fr/2MASS/H/Norder6/Dir30000/Npix30889.jpg')
+
+    shape_fits_precomp = (512, 512)
+    shape_jpg_precomp = (512, 512, 3)
+    data_precomp = [0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1]
+    assert fits_tile.data.shape == shape_fits_precomp
+    assert jpg_tile.data.shape == shape_jpg_precomp
+    assert list(fits_tile.data[510][:12]) == data_precomp
+
+def test_read_write():
+    fits_tile = HipsTile.read('fits', 'Npix30889.fits')
+    jpg_tile = HipsTile.read('jpg', 'Npix30889.jpg')
+
+    shape_fits_precomp = (512, 512)
+    shape_jpg_precomp = (512, 512, 3)
+    data_precomp = [0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 1]
+    assert (fits_tile.data.shape) == shape_fits_precomp
+    assert (jpg_tile.data.shape) == shape_jpg_precomp
+    assert list(fits_tile.data[510][:12]) == data_precomp
+
+    fits_tile.write('test_file.fits')
+    jpg_tile.write('test_file.jpg')
+
+    path_fits = fits_tile.path / 'test_file.fits'
+    path_jpg = jpg_tile.path / 'test_file.jpg'
+    assert True == path_fits.is_file()
+    assert True == path_jpg.is_file()

hips/tiles/tile.py

@@ -1,5 +1,5 @@
 # Licensed under a 3-clause BSD style license - see LICENSE.rst
-from .description import HipsDescription
+from astropy.io.fits.header import Header
 from astropy.io import fits
 from pathlib import Path
 from io import BytesIO
@@ -15,39 +15,25 @@
 class HipsTile:
     """HiPS tile container.
 
-    This class provides methods for fetching, reading,
-    and writing a HiPS tile. It also contains a few
-    getters and setters around frequently used
-    HiPS tile attributes.
+    This class provides methods for fetching, reading, and writing a HiPS tile.
 
     Parameters
     ----------
-    hips_description : `HipsDescription`
-        Class HipsDescription contains HiPS properties
-    order : `int`
-        Order of the HiPS tile
-    ipix : `int`
-        HEALPix pixel number
-    format : `format`
+    format : `str`
         Format of HiPS tile
-    data : `numpy.ndarray`
-        Pixel values of HiPS tile
-    tile_width : `int`
-        Width of HiPS tile
-    base_url : `str`
-        Base URL of HiPS tile
+    data : `int`
+        Data containing HiPS tile
+    header : `format`
+        Header of HiPS tile
 
     Examples
     --------
     ::
 
         >>> import urllib.request
-        >>> from hips.tiles import HipsDescription
         >>> from astropy.tests.helper import remote_data
         >>> text = urllib.request.urlopen('https://raw.githubusercontent.com/hipspy/hips/master/hips/tiles/tests/data/properties.txt').read() # doctest: +REMOTE_DATA
-        >>> hips_description = HipsDescription.parse(str(text))
-        >>> hips_tile = HipsTile(hips_description=hips_description, order=6, ipix=30889, format='fits', tile_width=512)
-        >>> hips_tile.read()
+        >>> hips_tile = HipsTile.read('fits', 'Npix30889.fits')
         >>> hips_tile.data
         array([[0, 0, 0, ..., 0, 0, 0],
                [0, 0, 0, ..., 0, 0, 0],
@@ -58,51 +44,57 @@ class HipsTile:
                [0, 0, 0, ..., 1, 0, 1]], dtype=int16)
         """
 
-    def __init__(self, hips_description: HipsDescription, order: int, ipix: int, format: str,
-                 data: np.ndarray=None, tile_width: int=512, base_url: str=None) -> None:
-        self.hips_description = hips_description
-        self.order = order
-        self.ipix = ipix
-        self.tile_width = tile_width
+    def __init__(self, format: str, data: np.ndarray=None, header: Header=None) -> None:
         self.format = format
         self.data = data
-        self.base_url = base_url
-
-    @staticmethod
-    def _directory(ipix: int) -> int:
-        """Directory of the HiPS tile (`int`)."""
-        return np.around(ipix, decimals=-(len(str(ipix)) - 1))
+        self.header = header
 
     @property
     def path(self) -> Path:
         """Default path for tile storage (`Path`)."""
         return Path('hips', 'tiles', 'tests', 'data')
 
-    @property
-    def tile_url(self) -> str:
-        """HiPS tile url (`str`)."""
-        return ''.join([self.base_url, '/Norder', str(self.order), '/Dir',
-               str(self._directory(self.ipix)), '/Npix', str(self.ipix), '.', self.format])
+    @classmethod
+    def fetch(cls, format: str, url: str) -> HipsTile:
+        """Fetch HiPS tile and load into memory (`HipsTile`).
 
-    def fetch(self) -> None:
-        """Fetch HiPS tile and load into memory (`None`)."""
-        raw_image = BytesIO(urllib.request.urlopen(self.tile_url).read())
-        if self.format == 'fits':
+        Parameters
+        ----------
+        format : `str`
+            Format of HiPS tile
+        url : `str`
+            URL containing HiPS tile
+        """
+        raw_image = BytesIO(urllib.request.urlopen(url).read())
+        if format == 'fits':
             hdulist = fits.open(raw_image)
-            self.data = np.array(hdulist[0].data)
-            self.header = hdulist[0].header
+            data = np.array(hdulist[0].data)
+            header = hdulist[0].header
+            return cls(format, data, header)
         else:
-            self.data = np.array(Image.open(raw_image))
+            data = np.array(Image.open(raw_image))
+            return cls(format, data)
 
-    def read(self) -> None:
-        """Read HiPS tile data from a directory and load into memory (`None`)."""
-        path = self.path / (''.join(['Npix', str(self.ipix), '.', self.format]))
-        if self.format == 'fits':
+    @classmethod
+    def read(cls, format: str, filename: str) -> 'HipsTile':
+        """Read HiPS tile data from a directory and load into memory (`HipsTile`).
+
+        Parameters
+        ----------
+        format : `str`
+            Format of HiPS tile
+        filename : `str`
+            File name of HiPS tile
+        """
+        path = Path('hips', 'tiles', 'tests', 'data') / filename
+        if format == 'fits':
             hdulist = fits.open(path)
-            self.data = np.array(hdulist[0].data)
-            self.header = hdulist[0].header
+            data = np.array(hdulist[0].data)
+            header = hdulist[0].header
+            return cls(format, data, header)
         else:
-            self.data = np.array(Image.open(str(path)))
+            data = np.array(Image.open(str(path)))
+            return cls(format, data)
 
     def write(self, filename: str) -> None:
         """Write HiPS tile by a given filename (`None`).
@@ -112,7 +104,7 @@ def write(self, filename: str) -> None:
         filename : `str`
             Name of the file
         """
-        path = self.path / (''.join([filename, '.', self.format]))
+        path = self.path / filename
         if self.format == 'fits':
             hdu = fits.PrimaryHDU(self.data, header=self.header)
             hdulist = fits.HDUList([hdu])