Issues with Azure Pipelines for Deploying GStreamer to Azure Function App (Linux)

Question

I'm currently working on a project where I need to integrate the Azure Speech SDK with GStreamer on a Function App (Linux environment). My primary goal is to utilize GStreamer for audio processing in conjunction with the Azure Speech SDK for speech-to-text capabilities. However, I'm encountering challenges in setting up GStreamer correctly to ensure it works seamlessly with the Speech SDK.

I am deploying the Function App using Azure Pipelines, installing the GStreamer libraries in the process:

    - bash: |
        python -m venv venv
        source venv/bin/activate
        pip install --target="$(workingDirectory)/.python_packages/lib/site-packages" -r requirements.txt
        pip list
      workingDirectory: $(workingDirectory)
      displayName: 'Install application dependencies'
          
    - script: |
        sudo apt-get update
        sudo apt-get install libgstreamer1.0-0 libunwind-dev libgstreamer1.0-dev libgstreamer-plugins-base1.0-dev libgstreamer-plugins-bad1.0-dev gstreamer1.0-plugins-base gstreamer1.0-plugins-good gstreamer1.0-plugins-bad gstreamer1.0-plugins-ugly gstreamer1.0-libav gstreamer1.0-tools gstreamer1.0-x gstreamer1.0-alsa gstreamer1.0-gl gstreamer1.0-gtk3 gstreamer1.0-qt5 gstreamer1.0-pulseaudio
      displayName: 'Install GStreamer'

followed by

  jobs:
  - deployment: Deploy
    displayName: Deploy
    environment: 'development'
    pool:
      vmImage: $(vmImageName)
    strategy:
      runOnce:
        deploy:

          steps:
          - task: AzureFunctionApp@1
            displayName: 'Azure functions app deploy'
            inputs:
              azureSubscription: '$(azureSubscription)'
              appType: functionAppLinux
              appName: $(functionAppName)
              package: '$(Pipeline.Workspace)/drop/$(Build.BuildId).zip'
              deploymentMethod: 'zipDeploy'
              appSettings: 
          - script: |
              sudo apt-get update
              sudo apt-get install libunwind-dev libgstreamer1.0-0 libgstreamer1.0-dev libgstreamer-plugins-base1.0-dev libgstreamer-plugins-bad1.0-dev gstreamer1.0-plugins-base gstreamer1.0-plugins-good gstreamer1.0-plugins-bad gstreamer1.0-plugins-ugly gstreamer1.0-libav gstreamer1.0-tools gstreamer1.0-x gstreamer1.0-alsa gstreamer1.0-gl gstreamer1.0-gtk3 gstreamer1.0-qt5 gstreamer1.0-pulseaudio
            displayName: 'Install GStreamer'

However, it seems that GStreamer is not deployed to the Function App itself as I am unable to find it using SSH (gst-launch-1.0) and get the following error when executing my function:

Error processing the request: Exception with error code: \n[CALL STACK BEGIN]\n\n/home/site/wwwroot/.python_packages/lib/site-packages/azure/cognitiveservices/speech/libMicrosoft.CognitiveServices.Speech.core.so(+0x18b2e1) [0x75f9b60202e1]\n/home/site/wwwroot/.python_packages/lib/site-packages/azure/cognitiveservices/speech/libMicrosoft.CognitiveServices.Speech.core.so(+0x140af7) [0x75f9b5fd5af7]\n/home/site/wwwroot/.python_packages/lib/site-packages/azure/cognitiveservices/speech/libMicrosoft.CognitiveServices.Speech.core.so(+0x1f945e) [0x75f9b608e45e]\n/home/site/wwwroot/.python_packages/lib/site-packages/azure/cognitiveservices/speech/libMicrosoft.CognitiveServices.Speech.core.so(+0x13e5a9) [0x75f9b5fd35a9]\n/home/site/wwwroot/.python_packages/lib/site-packages/azure/cognitiveservices/speech/libMicrosoft.CognitiveServices.Speech.core.so(+0x216d8a) [0x75f9b60abd8a]\n/home/site/wwwroot/.python_packages/lib/site-packages/azure/cognitiveservices/speech/libMicrosoft.CognitiveServices.Speech.core.so(recognizer_create_speech_recognizer_from_config+0x10b) [0x75f9b5f538fd]\n/usr/lib/x86_64-linux-gnu/libffi.so.7(+0x6d1d) [0x75f9d40a2d1d]\n/usr/lib/x86_64-linux-gnu/libffi.so.7(+0x6289) [0x75f9d40a2289]\n/usr/local/lib/python3.10/lib-dynload/_ctypes.cpython-310-x86_64-linux-gnu.so(+0xd97a) [0x75f9ddd2797a]\n/usr/local/lib/python3.10/lib-dynload/_ctypes.cpython-310-x86_64-linux-gnu.so(+0xe076) [0x75f9ddd28076]\n/usr/local/bin/../lib/libpython3.10.so.1.0(_PyObject_Call+0x5c) [0x75f9df1cfb0c]\n/usr/local/bin/../lib/libpython3.10.so.1.0(_PyEval_EvalFrameDefault+0x1f11) [0x75f9df1c13f1]\n/usr/local/bin/../lib/libpython3.10.so.1.0(+0x165c41) [0x75f9df1bec41]\n/usr/local/bin/../lib/libpython3.10.so.1.0(PyVectorcall_Call+0xc5) [0x75f9df21c025]\n/usr/local/bin/../lib/libpython3.10.so.1.0(_PyEval_EvalFrameDefault+0x1f11) [0x75f9df1c13f1]\n/usr/local/bin/../lib/libpython3.10.so.1.0(+0x165c41) [0x75f9df1bec41]\n/usr/local/bin/../lib/libpython3.10.so.1.0(_PyObject_FastCallDictTstate+0x12d) [0x75f9df1c596d]\n[CALL STACK END]\n\nException with an error code: 0x29 (SPXERR_GSTREAMER_NOT_FOUND_ERROR)

The function works perfectly fine locally with GStreamer installed, but fails once deployed to the function app.

Any help would be much appreciated!

Answer 1

The following step in your pipeline is just installing the GStreamer packages to the agent machine, and it will not install the packages to the function app on Azure.

- script: |
    sudo apt-get update
    sudo apt-get install libunwind-dev libgstreamer1.0-0 libgstreamer1.0-dev libgstreamer-plugins-base1.0-dev libgstreamer-plugins-bad1.0-dev gstreamer1.0-plugins-base gstreamer1.0-plugins-good gstreamer1.0-plugins-bad gstreamer1.0-plugins-ugly gstreamer1.0-libav gstreamer1.0-tools gstreamer1.0-x gstreamer1.0-alsa gstreamer1.0-gl gstreamer1.0-gtk3 gstreamer1.0-qt5 gstreamer1.0-pulseaudio
  displayName: 'Install GStreamer'

You need to install all the required packages into the directory "$(System.DefaultWorkingDirectory)/.python_packages/lib/site-packages", and then archive this directory together with the source files of function app to a ZIP file. Then in the deploy job, deploy the ZIP file to Azure Function App.

For more details, you can reference the documentation "Build and deploy using Azure Pipelines".