Synthesis black list

DB.py

@@ -1,3 +1,5 @@
+from datetime import datetime
+
 import peewee
 
 database = peewee.SqliteDatabase('voice_cache.sqlite')
@@ -18,5 +20,16 @@ class Speaker(BaseModel):
     speaker = peewee.CharField()
 
 
+class SynthesisErrors(peewee.Model):
+    speaker = peewee.CharField()
+    text = peewee.TextField()
+    timestamp = peewee.DateTimeField(default=datetime.now)
+
+    class Meta:
+        database = database
+        primary_key = peewee.CompositeKey('speaker', 'text')
+
+
 Prefix.create_table()
 Speaker.create_table()
+SynthesisErrors.create_table()

cogs/TTSCommands.py

@@ -1,4 +1,6 @@
 # -*- coding: utf-8 -*-
+import subprocess
+
 from discord.ext import commands
 from discord.ext.commands import Context
 import discord
@@ -62,10 +64,24 @@ class TTSCommands(commands.Cog, Observ.Observer):
 
         speaker: Speakers = await self._get_speaker(message.guild.id)
 
-        wav_file_like_object = self.tts.synthesize_text(message.content, speaker=speaker)
-        sound_source = FFmpegPCMAudio(wav_file_like_object, pipe=True)
+        # check if message will fail on synthesis
+        if DB.SynthesisErrors.select()\
+                .where(DB.SynthesisErrors.speaker == speaker.value)\
+                .where(DB.SynthesisErrors.text == message.content)\
+                .count() == 1:
+            # Then we will not try to synthesis it
+            await message.channel.send(f"I will not synthesis this message due to TTS engine limitations")
+            return
 
-        voice_client.play(sound_source)
+        try:
+            wav_file_like_object = self.tts.synthesize_text(message.content, speaker=speaker)
+            sound_source = FFmpegPCMAudio(wav_file_like_object, pipe=True, stderr=subprocess.PIPE)
+            voice_client.play(sound_source)
+
+        except Exception as synth_exception:
+            logger.warning(f'Exception on synthesize {message.content!r}: {synth_exception}', exc_info=synth_exception)
+            await message.channel.send(f'Internal error')
+            DB.SynthesisErrors.create(speaker=speaker.value, text=message.content)
 
     @commands.command('getAllSpeakers')
     async def get_speakers(self, ctx: Context):