Handle missing PortAudio system dependency

And add info about PortAudio to the README file.

.github/workflows/tests.yaml

@@ -35,6 +35,14 @@ jobs:
       - name: Check out repository
         uses: actions/checkout@v3
 
+      #----------------------------------------------
+      #           Install PortAudio
+      #----------------------------------------------
+      - name: Install PortAudio
+        run: |
+          apt-get update
+          apt-get --assume-yes install portaudio19-dev python-all-dev
+
       #----------------------------------------------
       #  --- configure poetry & install project  ----
       #----------------------------------------------

README.md

@@ -42,8 +42,13 @@ The package is written in Python. The web chatbot UI is made with [Streamlit](ht
 - Python >= 3.9
 - A valid [OpenAI API key](https://platform.openai.com/account/api-keys)
   - Set in the Web UI or through the environment variable `OPENAI_API_KEY`
+- Optionally, to enable voice chat, you also need:
+  - [PortAudio](https://www.portaudio.com/docs/v19-doxydocs/index.html)
+    - Install on Ubuntu with `sudo apt-get --assume-yes install portaudio19-dev python-all-dev`
+    - Install on CentOS/RHEL with `sudo yum install portaudio portaudio-devel`
 
 ## Installation
+This, naturally, assumes your systems fulfills all [requirements](#system-requirements).
 ### Using pip
 ```shell
 pip install pyrobbot
@@ -68,16 +73,17 @@ and general `rob` options. For info about specific subcommands and the
 options that apply to them only, **please run `rob SUBCOMMAND -h`** (note
 that the `-h` goes after the subcommand in this case).
 
-### Chatting by Voice
-```shell
-rob voice
-```
 
 ### Using the Web UI
 ```shell
 rob
 ```
 
+### Chatting by Voice
+```shell
+rob voice
+```
+
 ### Running on the Terminal
 ```shell
 rob .

pyproject.toml

@@ -4,7 +4,7 @@
   license = "MIT"
   name = "pyrobbot"
   readme = "README.md"
-  version = "0.2.0"
+  version = "0.2.1"
 
 [build-system]
   build-backend = "poetry.core.masonry.api"

pyrobbot/text_to_speech.py

@@ -7,13 +7,23 @@
 import numpy as np
 import pygame
 import scipy.io.wavfile as wav
-import sounddevice as sd
 import soundfile as sf
 import speech_recognition as sr
 from gtts import gTTS
 from loguru import logger
 from pygame import mixer
 
+try:
+    import sounddevice as sd
+
+    _sounddevice_imported = True
+except OSError as error:
+    logger.error(error)
+    logger.error(
+        "Can't use module `sounddevice`. Please check your system's PortAudio install."
+    )
+    _sounddevice_imported = False
+
 
 @dataclass
 class LiveAssistant:
@@ -25,6 +35,12 @@ class LiveAssistant:
     inactivity_sound_intensity_threshold: float = 0.02
 
     def __post_init__(self):
+        if not _sounddevice_imported:
+            logger.error(
+                "Module `sounddevice`, needed for audio recording, is not available."
+            )
+            logger.error("Cannot continue. Exiting.")
+            raise SystemExit(1)
         mixer.init()
 
     def speak(self, text):