Class: Prescient::Provider::HuggingFace

Inherits:
Base
  • Object
show all
Includes:
HTTParty
Defined in:
lib/prescient/provider/huggingface.rb

Overview

Hugging Face router-backed Inference Providers API adapter.

Constant Summary collapse

FEATURE_EXTRACTION_PATH =

Router path for the Hugging Face feature-extraction provider.

Returns:

  • (String) —

    Feature-extraction endpoint template

'/hf-inference/models/%<model>s/pipeline/feature-extraction'
CHAT_COMPLETIONS_PATH =

OpenAI-compatible router path for Hugging Face chat completions.

Returns:

  • (String) —

    Chat-completions endpoint path

'/v1/chat/completions'
MODEL_LIST_PATH =

OpenAI-compatible router path for listing available chat models.

Returns:

  • (String) —

    Model-list endpoint path

'/v1/models'
EMBEDDING_DIMENSIONS =

Known embedding dimensions for commonly used models.

{
  'sentence-transformers/all-MiniLM-L6-v2'     => 384,
  'sentence-transformers/all-mpnet-base-v2'    => 768,
  'sentence-transformers/all-roberta-large-v1' => 1024,
}.freeze

Instance Attribute Summary

Attributes inherited from Base

#options, #provider_name

Instance Method Summary collapse

Methods inherited from Base

#available?, #build_prompt, #clean_text, #default_context_configs, #default_prompt_templates, #extract_embedding_text, #extract_text_values, #format_context_item, #handle_errors, #validate_embedding_dimensions

Constructor Details

#initialize(**options) ⇒ HuggingFace

Returns a new instance of HuggingFace.



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# File 'lib/prescient/provider/huggingface.rb', line 30

def initialize(**options)
  super
  self.class.default_timeout(@options[:timeout] || 60)
end

Instance Method Details

#generate_embedding(text, **options) ⇒ Array<Float>

Generate an embedding through Hugging Face feature extraction.

Parameters:

  • text (String) —

    Text to embed

Returns:

  • (Array<Float>) —

    Embedding vector



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# File 'lib/prescient/provider/huggingface.rb', line 38

def generate_embedding(text, **options)
  handle_errors do
    clean_text_input = clean_text(text)

    embedding_model = options[:model] || @options[:embedding_model]
    response = self.class.post(FEATURE_EXTRACTION_PATH % { model: embedding_model },
                               headers: {
                                 'Content-Type'  => 'application/json',
                                 'Authorization' => "Bearer #{@options[:api_key]}",
                               },
                               body:    { inputs: clean_text_input }.to_json)

    validate_response!(response, 'embedding generation')

    # HuggingFace returns embeddings as nested arrays, get the first one
    embedding_data = response.parsed_response
    embedding_data = embedding_data.first if embedding_data.is_a?(Array) && embedding_data.first.is_a?(Array)

    raise Prescient::InvalidResponseError, 'No embedding returned' unless embedding_data.is_a?(Array)

    expected_dimensions = EMBEDDING_DIMENSIONS[embedding_model] || @options[:embedding_dimensions]
    unless expected_dimensions
      raise Prescient::Error,
            "Embedding dimensions are required for model #{embedding_model}"
    end

    validate_embedding_dimensions(embedding_data, expected_dimensions)
  end
end

#generate_response(prompt, context_items = [], **options) ⇒ Hash

Generate text through a Hugging Face text-generation model.

Parameters:

  • prompt (String) —

    Prompt to send

  • context_items (Array<Hash, String>) (defaults to: []) —

    Optional context items

Returns:

  • (Hash) —

    Normalized response data



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# File 'lib/prescient/provider/huggingface.rb', line 72

def generate_response(prompt, context_items = [], **options)
  handle_errors do
    formatted_prompt = build_prompt(prompt, context_items)

    response = self.class.post(CHAT_COMPLETIONS_PATH,
                               headers: {
                                 'Content-Type'  => 'application/json',
                                 'Authorization' => "Bearer #{@options[:api_key]}",
                               },
                               body:    {
                                 model:       options[:model] || @options[:chat_model],
                                 messages:    [{ role: 'user', content: formatted_prompt }],
                                 max_tokens:  options[:max_tokens] || 2000,
                                 temperature: options[:temperature] || 0.7,
                                 top_p:       options[:top_p] || 0.9,
                               }.to_json)

    validate_response!(response, 'text generation')

    parsed_response = response.parsed_response
    generated_text = parsed_response.dig('choices', 0, 'message', 'content') if parsed_response.is_a?(Hash)
    raise Prescient::InvalidResponseError, 'No response generated' unless generated_text

    {
      response:        generated_text.strip,
      model:           options[:model] || @options[:chat_model],
      provider:        'huggingface',
      processing_time: nil,
      metadata:        {
        usage:         parsed_response['usage'],
        finish_reason: parsed_response.dig('choices', 0, 'finish_reason'),
      },
    }
  end
end

#health_check ⇒ Hash

Check availability of the configured embedding and text models.

The embedding model is checked against the model metadata API on huggingface.co, while the chat model is checked against the router's OpenAI-compatible /v1/models listing. ready requires both checks to succeed.

Returns:

  • (Hash) —

    Provider health information



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# File 'lib/prescient/provider/huggingface.rb', line 116

def health_check
  handle_errors do
    embedding_response = self.class.get("https://huggingface.co/api/models/#{@options[:embedding_model]}",
                                        headers: { 'Authorization' => "Bearer #{@options[:api_key]}" })
    chat_response = self.class.get(MODEL_LIST_PATH,
                                   headers: { 'Authorization' => "Bearer #{@options[:api_key]}" })

    embedding_healthy = embedding_response.success?
    chat_models = chat_response.parsed_response['data'] || []
    chat_healthy = chat_response.success? && chat_models.any? { |model| model['id'] == @options[:chat_model] }

    {
      status:          embedding_healthy && chat_healthy ? 'healthy' : 'partial',
      provider:        'huggingface',
      reachable:       true,
      embedding_model: {
        name:      @options[:embedding_model],
        available: embedding_healthy,
      },
      chat_model:      {
        name:      @options[:chat_model],
        available: chat_healthy,
      },
      ready:           embedding_healthy && chat_healthy,
    }
  end
rescue Prescient::Error => e
  {
    status:    'unavailable',
    provider:  'huggingface',
    reachable: false,
    error:     e.class.name,
    message:   e.message,
    ready:     false,
  }
end

#list_models ⇒ Array<Hash>

Return the configured Hugging Face models.

This method does not query the Hugging Face APIs. It reflects the current adapter configuration only.

Returns:

  • (Array<Hash>) —

    Model descriptors



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# File 'lib/prescient/provider/huggingface.rb', line 159

def list_models
  # HuggingFace doesn't provide a simple API to list all models
  # Return the configured models
  [
    {
      name:       @options[:embedding_model],
      type:       'embedding',
      dimensions: EMBEDDING_DIMENSIONS[@options[:embedding_model]],
    },
    {
      name: @options[:chat_model],
      type: 'text-generation',
    },
  ]
end

#validate_configuration! ⇒ Object (protected)

Raises:



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# File 'lib/prescient/provider/huggingface.rb', line 177

def validate_configuration!
  missing_options = [:api_key, :embedding_model, :chat_model].select { |opt| @options[opt].nil? }
  return unless missing_options.any?

  raise Prescient::Error, "Missing required options: #{missing_options.join(', ')}"
end