Refactor exceptions

* Suffix names for custom exceptions with "Error"
* Introduce exceptions for when the coressponding encoder isn't found

spotdl/encode/encode_base.py

@@ -1,8 +1,11 @@
+import shutil
 import os
 
 from abc import ABC
 from abc import abstractmethod
 
+from spotdl.encode.exceptions import EncoderNotFoundError
+
 """
   NOTE ON ENCODERS
   ================
@@ -25,6 +28,12 @@ from abc import abstractmethod
 class EncoderBase(ABC):
     @abstractmethod
     def __init__(self, encoder_path, loglevel, additional_arguments):
+        if shutil.which(encoder_path) is None:
+            raise EncoderNotFoundError(
+                "{} executable does not exist or was not found in PATH.".format(
+                    encoder_path
+                )
+            )
         self.encoder_path = encoder_path
         self._loglevel = loglevel
         self._additional_arguments = additional_arguments

spotdl/encode/encoders/avconv.py

@@ -2,16 +2,21 @@ import subprocess
 import os
 from logzero import logger as log
 from spotdl.encode import EncoderBase
+from spotdl.encode.exceptions import EncoderNotFoundError
+from spotdl.encode.exceptions import AvconvNotFoundError
 
 class EncoderAvconv(EncoderBase):
     def __init__(self, encoder_path="avconv"):
-        print("Using avconv is deprecated and this will be removed in",
-              "future versions. Use ffmpeg instead.")
+        print("Using EncoderAvconv is deprecated and will be removed"
+              "in future versions. Use EncoderFFmpeg instead.")
         encoder_path = encoder_path
         _loglevel = "-loglevel 0"
         _additional_arguments = ["-ab", "192k"]
 
-        super().__init__(encoder_path, _loglevel, _additional_arguments)
+        try:
+            super().__init__(encoder_path, _loglevel, _additional_arguments)
+        except EncoderNotFoundError as e:
+            raise AvconvNotFoundError(e.args[0])
 
     def set_argument(self, argument):
         super().set_argument(argument)

spotdl/encode/encoders/ffmpeg.py

@@ -1,7 +1,10 @@
 import subprocess
 import os
 from logzero import logger as log
+
 from spotdl.encode import EncoderBase
+from spotdl.encode.exceptions import EncoderNotFoundError
+from spotdl.encode.exceptions import FFmpegNotFoundError
 
 RULES = {
     "m4a": {
@@ -17,14 +20,15 @@ RULES = {
     },
 }
 
+
 class EncoderFFmpeg(EncoderBase):
     def __init__(self, encoder_path="ffmpeg"):
-        encoder_path = encoder_path
         _loglevel = "-hide_banner -nostats -v panic"
         _additional_arguments = ["-b:a", "192k", "-vn"]
-
-        super().__init__(encoder_path, _loglevel, _additional_arguments)
-
+        try:
+            super().__init__(encoder_path, _loglevel, _additional_arguments)
+        except EncoderNotFoundError as e:
+            raise FFmpegNotFoundError(e.args[0])
         self._rules = RULES
 
     def set_argument(self, argument):
@@ -41,18 +45,16 @@ class EncoderFFmpeg(EncoderBase):
         if initial_arguments is None:
             raise TypeError(
                 'The input format ("{}") is not supported.'.format(
-                input_extension,
+                input_encoding,
             )
         )
-
         arguments = initial_arguments.get(output_encoding)
         if arguments is None:
             raise TypeError(
                 'The output format ("{}") is not supported.'.format(
-                output_extension,
+                output_encoding,
             )
         )
-
         return arguments
 
     def set_debuglog(self):
@@ -61,12 +63,10 @@ class EncoderFFmpeg(EncoderBase):
     def _generate_encode_command(self, input_file, output_file):
         input_encoding = self.get_encoding(input_file)
         output_encoding = self.get_encoding(output_file)
-
         arguments = self._generate_encoding_arguments(
             input_encoding,
             output_encoding
         )
-
         command = [self.encoder_path] \
             + ["-y", "-nostdin"] \
             + self._loglevel.split() \
@@ -82,10 +82,8 @@ class EncoderFFmpeg(EncoderBase):
             input_file,
             output_file
         )
-
         returncode = subprocess.call(encode_command)
         encode_successful = returncode == 0
-
         if encode_successful and delete_original:
             os.remove(input_file)
 

spotdl/encode/encoders/tests/test_ffmpeg.py

@@ -0,0 +1,188 @@
+from spotdl.encode import EncoderBase
+# from spotdl.encode import exceptions
+from spotdl.encode.encoders import EncoderFFmpeg
+
+import pytest
+
+
+class TestEncoderFFmpeg:
+    def test_subclass(self):
+        assert issubclass(EncoderFFmpeg, EncoderBase)
+
+
+class TestEncodingDefaults:
+    def m4a_to_mp3_encoder(input_file, output_file):
+        command = [
+            'ffmpeg', '-y', '-nostdin', '-hide_banner', '-nostats', '-v', 'panic',
+            '-i', input_file,
+            '-codec:v', 'copy',
+            '-codec:a', 'libmp3lame',
+            '-ar', '48000',
+            '-b:a', '192k',
+            '-vn', output_file
+        ]
+        return command
+
+    def m4a_to_webm_encoder(input_file, output_file):
+        command = [
+            'ffmpeg', '-y', '-nostdin', '-hide_banner', '-nostats', '-v', 'panic',
+            '-i', input_file,
+            '-codec:a', 'libopus',
+            '-vbr', 'on',
+            '-b:a', '192k',
+            '-vn', output_file
+        ]
+        return command
+
+    def m4a_to_m4a_encoder(input_file, output_file):
+        command = [
+            'ffmpeg', '-y', '-nostdin', '-hide_banner', '-nostats', '-v', 'panic',
+            '-i', input_file,
+            '-acodec', 'copy',
+            '-b:a', '192k',
+            '-vn', output_file
+        ]
+        return command
+
+    def m4a_to_flac_encoder(input_file, output_file):
+        command = [
+            'ffmpeg', '-y', '-nostdin', '-hide_banner', '-nostats', '-v', 'panic',
+            '-i', input_file,
+            '-codec:a', 'flac',
+            '-ar', '48000',
+            '-b:a', '192k',
+            '-vn', output_file
+        ]
+        return command
+
+    @pytest.mark.parametrize("files, expected_command", [
+        (("test.m4a", "test.mp3"), m4a_to_mp3_encoder("test.m4a", "test.mp3")),
+        (("abc.m4a", "cba.webm"), m4a_to_webm_encoder("abc.m4a", "cba.webm")),
+        (("bla bla.m4a", "ble ble.m4a"), m4a_to_m4a_encoder("bla bla.m4a", "ble ble.m4a")),
+        (("😛.m4a", "• tongue.flac"), m4a_to_flac_encoder("😛.m4a", "• tongue.flac")),
+    ])
+    def test_generate_encode_command(self, files, expected_command):
+        encoder = EncoderFFmpeg()
+        assert encoder._generate_encode_command(*files) == expected_command
+
+
+class TestEncodingInDebugMode:
+    def m4a_to_mp3_encoder_with_debug(input_file, output_file):
+        command = [
+            'ffmpeg', '-y', '-nostdin', '-loglevel', 'debug',
+            '-i', input_file,
+            '-codec:v', 'copy',
+            '-codec:a', 'libmp3lame',
+            '-ar', '48000',
+            '-b:a', '192k',
+            '-vn', output_file
+        ]
+        return command
+
+    def m4a_to_webm_encoder_with_debug(input_file, output_file):
+        command = [
+            'ffmpeg', '-y', '-nostdin', '-loglevel', 'debug',
+            '-i', input_file,
+            '-codec:a', 'libopus',
+            '-vbr', 'on',
+            '-b:a', '192k',
+            '-vn', output_file
+        ]
+        return command
+
+    def m4a_to_m4a_encoder_with_debug(input_file, output_file):
+        command = [
+            'ffmpeg', '-y', '-nostdin', '-loglevel', 'debug',
+            '-i', input_file,
+            '-acodec', 'copy',
+            '-b:a', '192k',
+            '-vn', output_file
+        ]
+        return command
+
+    def m4a_to_flac_encoder_with_debug(input_file, output_file):
+        command = [
+            'ffmpeg', '-y', '-nostdin', '-loglevel', 'debug',
+            '-i', input_file,
+            '-codec:a', 'flac',
+            '-ar', '48000',
+            '-b:a', '192k',
+            '-vn', output_file
+        ]
+        return command
+
+    @pytest.mark.parametrize("files, expected_command", [
+        (("test.m4a", "test.mp3"), m4a_to_mp3_encoder_with_debug("test.m4a", "test.mp3")),
+        (("abc.m4a", "cba.webm"), m4a_to_webm_encoder_with_debug("abc.m4a", "cba.webm")),
+        (("bla bla.m4a", "ble ble.m4a"), m4a_to_m4a_encoder_with_debug("bla bla.m4a", "ble ble.m4a")),
+        (("😛.m4a", "• tongue.flac"), m4a_to_flac_encoder_with_debug("😛.m4a", "• tongue.flac")),
+    ])
+    def test_generate_encode_command_with_debug(self, files, expected_command):
+        encoder = EncoderFFmpeg()
+        encoder.set_debuglog()
+        assert encoder._generate_encode_command(*files) == expected_command
+
+
+class TestEncodingAndTrimSilence:
+    def m4a_to_mp3_encoder_and_trim_silence(input_file, output_file):
+        command = [
+            'ffmpeg', '-y', '-nostdin', '-hide_banner', '-nostats', '-v', 'panic',
+            '-i', input_file,
+            '-codec:v', 'copy',
+            '-codec:a', 'libmp3lame',
+            '-ar', '48000',
+            '-b:a', '192k',
+            '-vn',
+            '-af', 'silenceremove=start_periods=1',
+            output_file
+        ]
+        return command
+
+    def m4a_to_webm_encoder_and_trim_silence(input_file, output_file):
+        command = [
+            'ffmpeg', '-y', '-nostdin', '-hide_banner', '-nostats', '-v', 'panic',
+            '-i', input_file,
+            '-codec:a', 'libopus',
+            '-vbr', 'on',
+            '-b:a', '192k',
+            '-vn',
+            '-af', 'silenceremove=start_periods=1',
+            output_file
+        ]
+        return command
+
+    def m4a_to_m4a_encoder_and_trim_silence(input_file, output_file):
+        command = [
+            'ffmpeg', '-y', '-nostdin', '-hide_banner', '-nostats', '-v', 'panic',
+            '-i', input_file,
+            '-acodec', 'copy',
+            '-b:a', '192k',
+            '-vn',
+            '-af', 'silenceremove=start_periods=1',
+            output_file
+        ]
+        return command
+
+    def m4a_to_flac_encoder_and_trim_silence(input_file, output_file):
+        command = [
+            'ffmpeg', '-y', '-nostdin', '-hide_banner', '-nostats', '-v', 'panic',
+            '-i', input_file,
+            '-codec:a', 'flac',
+            '-ar', '48000',
+            '-b:a', '192k',
+            '-vn',
+            '-af', 'silenceremove=start_periods=1',
+            output_file
+        ]
+        return command
+
+    @pytest.mark.parametrize("files, expected_command", [
+        (("test.m4a", "test.mp3"), m4a_to_mp3_encoder_and_trim_silence("test.m4a", "test.mp3")),
+        (("abc.m4a", "cba.webm"), m4a_to_webm_encoder_and_trim_silence("abc.m4a", "cba.webm")),
+        (("bla bla.m4a", "ble ble.m4a"), m4a_to_m4a_encoder_and_trim_silence("bla bla.m4a", "ble ble.m4a")),
+        (("😛.m4a", "• tongue.flac"), m4a_to_flac_encoder_and_trim_silence("😛.m4a", "• tongue.flac")),
+    ])
+    def test_generate_encode_command_and_trim_silence(self, files, expected_command):
+        encoder = EncoderFFmpeg()
+        encoder.set_trim_silence()
+        assert encoder._generate_encode_command(*files) == expected_command

spotdl/encode/exceptions.py

@@ -0,0 +1,20 @@
+class EncoderNotFoundError(Exception):
+    __module__ = Exception.__module__
+
+    def __init__(self, message=None):
+        super(EncoderNotFoundError, self).__init__(message)
+
+
+class FFmpegNotFoundError(EncoderNotFoundError):
+    __module__ = Exception.__module__
+
+    def __init__(self, message=None):
+        super(FFmpegNotFoundError, self).__init__(message)
+
+
+class AvconvNotFoundError(EncoderNotFoundError):
+    __module__ = Exception.__module__
+
+    def __init__(self, message=None):
+        super(AvconvNotFoundError, self).__init__(message)
+

spotdl/encode/tests/test_encode_base.py

@@ -0,0 +1,13 @@
+from spotdl.encode import EncoderBase
+
+import pytest
+
+def test_abstract_base_class_encoderbase():
+    encoder_path = "ffmpeg"
+    _loglevel = "-hide_banner -nostats -v panic"
+    _additional_arguments = ["-b:a", "192k", "-vn"]
+
+    with pytest.raises(TypeError):
+        # This abstract base class must be inherited from
+        # for instantiation
+        EncoderBase(encoder_path, _loglevel, _additional_arguments)

spotdl/encode/tests/test_exceptions.py

@@ -0,0 +1,14 @@
+from spotdl.encode.exceptions import EncoderNotFoundError
+from spotdl.encode.exceptions import FFmpegNotFoundError
+from spotdl.encode.exceptions import AvconvNotFoundError
+
+import pytest
+
+
+class TestEncoderNotFoundSubclass:
+    def test_ffmpeg_not_found_subclass(self):
+        assert issubclass(FFmpegNotFoundError, EncoderNotFoundError)
+
+    def test_avconv_not_found_subclass(self):
+        assert issubclass(AvconvNotFoundError, EncoderNotFoundError)
+