ClassifAI Text-to-Speech Feature Flow (with OpenAI)

This diagram illustrates the sequence of operations when a user triggers the Text-to-Speech feature in ClassifAI using OpenAI as the provider. It shows the interaction between the WordPress application layers, the database, and the external OpenAI API.

Key Database Interactions:

• wp_posts: Stores the original post content and details for the generated audio attachment.
• wp_postmeta:
  • For the original post: Stores metadata like _classifai_post_audio_id (ID of the audio attachment), _classifai_post_audio_timestamp, _classifai_display_generated_audio (boolean to control frontend display), _classifai_post_audio_hash, and _classifai_text_to_speech_error (if any error occurs).
  • For the attachment: Standard WordPress attachment metadata.
• wp_options: Stores ClassifAI plugin settings, including feature enablement, selected provider (OpenAI), OpenAI API key, and selected voice/model for Text-to-Speech.

WordPress REST API Endpoint:

• Endpoint: GET /classifai/v1/synthesize-speech/{post_id}
• Purpose: Triggers the speech synthesis process for a given post.
• Handler: Classifai\Features\TextToSpeech::rest_endpoint_callback()
• Response: JSON indicating success or failure, including the audio_id if successful.

OpenAI API Endpoint:

• Endpoint: POST https://api.openai.com/v1/audio/speech
• Purpose: Converts text input to audio.
• Key Request Data: model (e.g., tts-1, tts-1-hd), input (the text to synthesize), voice (e.g., alloy, nova).
• Authentication: Via API Key in request headers.
• Response: Audio stream (e.g., MP3 format).