From 1fcb39ea64192fc83e7b52f067856bdf977ec2c1 Mon Sep 17 00:00:00 2001 From: Barry Warsaw Date: Thu, 14 Apr 2022 17:48:59 -0700 Subject: gh-91520: Rewrite imghdr inlining for clarity and completeness (#91521) * Rewrite imghdr inlining for clarity and completeness * Move MIMEImage class back closer to the top of the file since it's the important thing. * Use a decorate to mark a given rule function and simplify the rule function names for clarity. * Copy over all the imghdr test data files into the email package's test data directory. This way when imghdr is actually removed, it won't affect the MIMEImage guessing tests. * Rewrite and extend the MIMEImage tests to test for all supported auto-detected MIME image subtypes. * Remove the now redundant PyBanner048.gif data file. * See https://github.com/python/cpython/pull/91461#discussion_r850313336 Co-authored-by: Oleg Iarygin Co-authored-by: Oleg Iarygin --- Doc/includes/email-mime.py | 10 +-- Lib/email/mime/image.py | 140 ++++++++++++++++--------------- Lib/test/test_email/data/PyBanner048.gif | Bin 896 -> 0 bytes Lib/test/test_email/data/python.bmp | Bin 0 -> 1162 bytes Lib/test/test_email/data/python.exr | Bin 0 -> 2635 bytes Lib/test/test_email/data/python.gif | Bin 0 -> 405 bytes Lib/test/test_email/data/python.jpg | Bin 0 -> 543 bytes Lib/test/test_email/data/python.pbm | 3 + Lib/test/test_email/data/python.pgm | Bin 0 -> 269 bytes Lib/test/test_email/data/python.png | Bin 0 -> 1020 bytes Lib/test/test_email/data/python.ppm | Bin 0 -> 781 bytes Lib/test/test_email/data/python.ras | Bin 0 -> 1056 bytes Lib/test/test_email/data/python.sgi | Bin 0 -> 1967 bytes Lib/test/test_email/data/python.tiff | Bin 0 -> 1326 bytes Lib/test/test_email/data/python.webp | Bin 0 -> 432 bytes Lib/test/test_email/data/python.xbm | 6 ++ Lib/test/test_email/test_email.py | 34 ++++++-- 17 files changed, 114 insertions(+), 79 deletions(-) delete mode 100644 Lib/test/test_email/data/PyBanner048.gif create mode 100644 Lib/test/test_email/data/python.bmp create mode 100644 Lib/test/test_email/data/python.exr create mode 100644 Lib/test/test_email/data/python.gif create mode 100644 Lib/test/test_email/data/python.jpg create mode 100644 Lib/test/test_email/data/python.pbm create mode 100644 Lib/test/test_email/data/python.pgm create mode 100644 Lib/test/test_email/data/python.png create mode 100644 Lib/test/test_email/data/python.ppm create mode 100644 Lib/test/test_email/data/python.ras create mode 100644 Lib/test/test_email/data/python.sgi create mode 100644 Lib/test/test_email/data/python.tiff create mode 100644 Lib/test/test_email/data/python.webp create mode 100644 Lib/test/test_email/data/python.xbm diff --git a/Doc/includes/email-mime.py b/Doc/includes/email-mime.py index c87db6a..34c6bdb 100644 --- a/Doc/includes/email-mime.py +++ b/Doc/includes/email-mime.py @@ -1,7 +1,7 @@ -# Import smtplib for the actual sending function +# Import smtplib for the actual sending function. import smtplib -# Here are the email package modules we'll need +# Here are the email package modules we'll need. from email.message import EmailMessage # Create the container email message. @@ -13,13 +13,13 @@ msg['From'] = me msg['To'] = ', '.join(family) msg.preamble = 'You will not see this in a MIME-aware mail reader.\n' -# Open the files in binary mode. Use imghdr to figure out the -# MIME subtype for each specific image. +# Open the files in binary mode. You can also omit the subtype +# if you want MIMEImage to guess it. for file in pngfiles: with open(file, 'rb') as fp: img_data = fp.read() msg.add_attachment(img_data, maintype='image', - subtype='jpeg') + subtype='png') # Send the email via our own SMTP server. with smtplib.SMTP('localhost') as s: diff --git a/Lib/email/mime/image.py b/Lib/email/mime/image.py index fac238c..e19dea9 100644 --- a/Lib/email/mime/image.py +++ b/Lib/email/mime/image.py @@ -10,137 +10,143 @@ from email import encoders from email.mime.nonmultipart import MIMENonMultipart +class MIMEImage(MIMENonMultipart): + """Class for generating image/* type MIME documents.""" + + def __init__(self, _imagedata, _subtype=None, + _encoder=encoders.encode_base64, *, policy=None, **_params): + """Create an image/* type MIME document. + + _imagedata is a string containing the raw image data. If the data + type can be detected (jpeg, png, gif, tiff, rgb, pbm, pgm, ppm, + rast, xbm, bmp, webp, and exr attempted), then the subtype will be + automatically included in the Content-Type header. Otherwise, you can + specify the specific image subtype via the _subtype parameter. + + _encoder is a function which will perform the actual encoding for + transport of the image data. It takes one argument, which is this + Image instance. It should use get_payload() and set_payload() to + change the payload to the encoded form. It should also add any + Content-Transfer-Encoding or other headers to the message as + necessary. The default encoding is Base64. + + Any additional keyword arguments are passed to the base class + constructor, which turns them into parameters on the Content-Type + header. + """ + _subtype = _what(_imagedata) if _subtype is None else _subtype + if _subtype is None: + raise TypeError('Could not guess image MIME subtype') + MIMENonMultipart.__init__(self, 'image', _subtype, policy=policy, + **_params) + self.set_payload(_imagedata) + _encoder(self) + + +_rules = [] + + # Originally from the imghdr module. -def _what(h): - for tf in tests: - if res := tf(h): +def _what(data): + for rule in _rules: + if res := rule(data): return res else: return None -tests = [] -def _test_jpeg(h): +def rule(rulefunc): + _rules.append(rulefunc) + return rulefunc + + +@rule +def _jpeg(h): """JPEG data with JFIF or Exif markers; and raw JPEG""" if h[6:10] in (b'JFIF', b'Exif'): return 'jpeg' elif h[:4] == b'\xff\xd8\xff\xdb': return 'jpeg' -tests.append(_test_jpeg) -def _test_png(h): +@rule +def _png(h): if h.startswith(b'\211PNG\r\n\032\n'): return 'png' -tests.append(_test_png) -def _test_gif(h): +@rule +def _gif(h): """GIF ('87 and '89 variants)""" if h[:6] in (b'GIF87a', b'GIF89a'): return 'gif' -tests.append(_test_gif) -def _test_tiff(h): +@rule +def _tiff(h): """TIFF (can be in Motorola or Intel byte order)""" if h[:2] in (b'MM', b'II'): return 'tiff' -tests.append(_test_tiff) -def _test_rgb(h): +@rule +def _rgb(h): """SGI image library""" if h.startswith(b'\001\332'): return 'rgb' -tests.append(_test_rgb) -def _test_pbm(h): +@rule +def _pbm(h): """PBM (portable bitmap)""" if len(h) >= 3 and \ - h[0] == ord(b'P') and h[1] in b'14' and h[2] in b' \t\n\r': + h[0] == ord(b'P') and h[1] in b'14' and h[2] in b' \t\n\r': return 'pbm' -tests.append(_test_pbm) -def _test_pgm(h): +@rule +def _pgm(h): """PGM (portable graymap)""" if len(h) >= 3 and \ - h[0] == ord(b'P') and h[1] in b'25' and h[2] in b' \t\n\r': + h[0] == ord(b'P') and h[1] in b'25' and h[2] in b' \t\n\r': return 'pgm' -tests.append(_test_pgm) -def _test_ppm(h): +@rule +def _ppm(h): """PPM (portable pixmap)""" if len(h) >= 3 and \ - h[0] == ord(b'P') and h[1] in b'36' and h[2] in b' \t\n\r': + h[0] == ord(b'P') and h[1] in b'36' and h[2] in b' \t\n\r': return 'ppm' -tests.append(_test_ppm) -def _test_rast(h): +@rule +def _rast(h): """Sun raster file""" if h.startswith(b'\x59\xA6\x6A\x95'): return 'rast' -tests.append(_test_rast) -def _test_xbm(h): +@rule +def _xbm(h): """X bitmap (X10 or X11)""" if h.startswith(b'#define '): return 'xbm' -tests.append(_test_xbm) -def _test_bmp(h): +@rule +def _bmp(h): if h.startswith(b'BM'): return 'bmp' -tests.append(_test_bmp) -def _test_webp(h): +@rule +def _webp(h): if h.startswith(b'RIFF') and h[8:12] == b'WEBP': return 'webp' -tests.append(_test_webp) -def _test_exr(h): +@rule +def _exr(h): if h.startswith(b'\x76\x2f\x31\x01'): return 'exr' - -tests.append(_test_exr) - - -class MIMEImage(MIMENonMultipart): - """Class for generating image/* type MIME documents.""" - - def __init__(self, _imagedata, _subtype=None, - _encoder=encoders.encode_base64, *, policy=None, **_params): - """Create an image/* type MIME document. - - _imagedata is a string containing the raw image data. If the data - type can be detected (jpeg, png, gif, tiff, rgb, pbm, pgm, ppm, - rast, xbm, bmp, webp, and exr attempted), then the subtype will be - automatically included in the Content-Type header. Otherwise, you can - specify the specific image subtype via the _subtype parameter. - - _encoder is a function which will perform the actual encoding for - transport of the image data. It takes one argument, which is this - Image instance. It should use get_payload() and set_payload() to - change the payload to the encoded form. It should also add any - Content-Transfer-Encoding or other headers to the message as - necessary. The default encoding is Base64. - - Any additional keyword arguments are passed to the base class - constructor, which turns them into parameters on the Content-Type - header. - """ - if _subtype is None: - if (_subtype := _what(_imagedata)) is None: - raise TypeError('Could not guess image MIME subtype') - MIMENonMultipart.__init__(self, 'image', _subtype, policy=policy, - **_params) - self.set_payload(_imagedata) - _encoder(self) diff --git a/Lib/test/test_email/data/PyBanner048.gif b/Lib/test/test_email/data/PyBanner048.gif deleted file mode 100644 index 7e308f5..0000000 Binary files a/Lib/test/test_email/data/PyBanner048.gif and /dev/null differ diff --git a/Lib/test/test_email/data/python.bmp b/Lib/test/test_email/data/python.bmp new file mode 100644 index 0000000..675f951 Binary files /dev/null and b/Lib/test/test_email/data/python.bmp differ diff --git a/Lib/test/test_email/data/python.exr b/Lib/test/test_email/data/python.exr new file mode 100644 index 0000000..773c81e Binary files /dev/null and b/Lib/test/test_email/data/python.exr differ diff --git a/Lib/test/test_email/data/python.gif b/Lib/test/test_email/data/python.gif new file mode 100644 index 0000000..efa0be3 Binary files /dev/null and b/Lib/test/test_email/data/python.gif differ diff --git a/Lib/test/test_email/data/python.jpg b/Lib/test/test_email/data/python.jpg new file mode 100644 index 0000000..21222c0 Binary files /dev/null and b/Lib/test/test_email/data/python.jpg differ diff --git a/Lib/test/test_email/data/python.pbm b/Lib/test/test_email/data/python.pbm new file mode 100644 index 0000000..1848ba7 --- /dev/null +++ b/Lib/test/test_email/data/python.pbm @@ -0,0 +1,3 @@ +P4 +16 16 +ûñ¿úßÕ­±[ñ¥a_ÁX°°ðððð?ÿÿ \ No newline at end of file diff --git a/Lib/test/test_email/data/python.pgm b/Lib/test/test_email/data/python.pgm new file mode 100644 index 0000000..8349f2a Binary files /dev/null and b/Lib/test/test_email/data/python.pgm differ diff --git a/Lib/test/test_email/data/python.png b/Lib/test/test_email/data/python.png new file mode 100644 index 0000000..1a987f7 Binary files /dev/null and b/Lib/test/test_email/data/python.png differ diff --git a/Lib/test/test_email/data/python.ppm b/Lib/test/test_email/data/python.ppm new file mode 100644 index 0000000..7d9cdb3 Binary files /dev/null and b/Lib/test/test_email/data/python.ppm differ diff --git a/Lib/test/test_email/data/python.ras b/Lib/test/test_email/data/python.ras new file mode 100644 index 0000000..130e96f Binary files /dev/null and b/Lib/test/test_email/data/python.ras differ diff --git a/Lib/test/test_email/data/python.sgi b/Lib/test/test_email/data/python.sgi new file mode 100644 index 0000000..ffe9081 Binary files /dev/null and b/Lib/test/test_email/data/python.sgi differ diff --git a/Lib/test/test_email/data/python.tiff b/Lib/test/test_email/data/python.tiff new file mode 100644 index 0000000..39d0bfc Binary files /dev/null and b/Lib/test/test_email/data/python.tiff differ diff --git a/Lib/test/test_email/data/python.webp b/Lib/test/test_email/data/python.webp new file mode 100644 index 0000000..e824ec7 Binary files /dev/null and b/Lib/test/test_email/data/python.webp differ diff --git a/Lib/test/test_email/data/python.xbm b/Lib/test/test_email/data/python.xbm new file mode 100644 index 0000000..cfbee2e --- /dev/null +++ b/Lib/test/test_email/data/python.xbm @@ -0,0 +1,6 @@ +#define python_width 16 +#define python_height 16 +static char python_bits[] = { + 0xDF, 0xFE, 0x8F, 0xFD, 0x5F, 0xFB, 0xAB, 0xFE, 0xB5, 0x8D, 0xDA, 0x8F, + 0xA5, 0x86, 0xFA, 0x83, 0x1A, 0x80, 0x0D, 0x80, 0x0D, 0x80, 0x0F, 0xE0, + 0x0F, 0xF8, 0x0F, 0xF8, 0x0F, 0xFC, 0xFF, 0xFF, }; diff --git a/Lib/test/test_email/test_email.py b/Lib/test/test_email/test_email.py index b87dae2..6ead594 100644 --- a/Lib/test/test_email/test_email.py +++ b/Lib/test/test_email/test_email.py @@ -798,7 +798,7 @@ class TestMessageAPI(TestEmailBase): class TestEncoders(unittest.TestCase): def test_EncodersEncode_base64(self): - with openfile('PyBanner048.gif', 'rb') as fp: + with openfile('python.gif', 'rb') as fp: bindata = fp.read() mimed = email.mime.image.MIMEImage(bindata) base64ed = mimed.get_payload() @@ -1555,24 +1555,44 @@ class TestMIMEAudio(unittest.TestCase): # Test the basic MIMEImage class class TestMIMEImage(unittest.TestCase): - def setUp(self): - with openfile('PyBanner048.gif', 'rb') as fp: + def _make_image(self, ext): + with openfile(f'python.{ext}', 'rb') as fp: self._imgdata = fp.read() self._im = MIMEImage(self._imgdata) def test_guess_minor_type(self): - self.assertEqual(self._im.get_content_type(), 'image/gif') + for ext, subtype in { + 'bmp': None, + 'exr': None, + 'gif': None, + 'jpg': 'jpeg', + 'pbm': None, + 'pgm': None, + 'png': None, + 'ppm': None, + 'ras': 'rast', + 'sgi': 'rgb', + 'tiff': None, + 'webp': None, + 'xbm': None, + }.items(): + self._make_image(ext) + subtype = ext if subtype is None else subtype + self.assertEqual(self._im.get_content_type(), f'image/{subtype}') def test_encoding(self): + self._make_image('gif') payload = self._im.get_payload() self.assertEqual(base64.decodebytes(bytes(payload, 'ascii')), - self._imgdata) + self._imgdata) def test_checkSetMinor(self): + self._make_image('gif') im = MIMEImage(self._imgdata, 'fish') self.assertEqual(im.get_content_type(), 'image/fish') def test_add_header(self): + self._make_image('gif') eq = self.assertEqual self._im.add_header('Content-Disposition', 'attachment', filename='dingusfish.gif') @@ -1747,7 +1767,7 @@ class TestMIMEText(unittest.TestCase): # Test complicated multipart/* messages class TestMultipart(TestEmailBase): def setUp(self): - with openfile('PyBanner048.gif', 'rb') as fp: + with openfile('python.gif', 'rb') as fp: data = fp.read() container = MIMEBase('multipart', 'mixed', boundary='BOUNDARY') image = MIMEImage(data, name='dingusfish.gif') @@ -3444,7 +3464,7 @@ multipart/report def test_mime_classes_policy_argument(self): with openfile('audiotest.au', 'rb') as fp: audiodata = fp.read() - with openfile('PyBanner048.gif', 'rb') as fp: + with openfile('python.gif', 'rb') as fp: bindata = fp.read() classes = [ (MIMEApplication, ('',)), -- cgit v0.12