discourse-ai/lib/inference/hugging_face_text_generatio...

147 lines
4.5 KiB
Ruby

# frozen_string_literal: true
module ::DiscourseAi
module Inference
class HuggingFaceTextGeneration
CompletionFailed = Class.new(StandardError)
TIMEOUT = 120
def self.perform!(
prompt,
model,
temperature: 0.7,
top_p: nil,
top_k: nil,
typical_p: nil,
max_tokens: 2000,
repetition_penalty: 1.1,
user_id: nil,
tokenizer: DiscourseAi::Tokenizer::Llama2Tokenizer,
token_limit: nil
)
raise CompletionFailed if model.blank?
url = URI(SiteSetting.ai_hugging_face_api_url)
headers = { "Content-Type" => "application/json" }
if SiteSetting.ai_hugging_face_api_key.present?
headers["Authorization"] = "Bearer #{SiteSetting.ai_hugging_face_api_key}"
end
token_limit = token_limit || SiteSetting.ai_hugging_face_token_limit
parameters = {}
payload = { inputs: prompt, parameters: parameters }
prompt_size = tokenizer.size(prompt)
parameters[:top_p] = top_p if top_p
parameters[:top_k] = top_k if top_k
parameters[:typical_p] = typical_p if typical_p
parameters[:max_new_tokens] = token_limit - prompt_size
parameters[:temperature] = temperature if temperature
parameters[:repetition_penalty] = repetition_penalty if repetition_penalty
parameters[:return_full_text] = false
payload[:stream] = true if block_given?
Net::HTTP.start(
url.host,
url.port,
use_ssl: url.scheme == "https",
read_timeout: TIMEOUT,
open_timeout: TIMEOUT,
write_timeout: TIMEOUT,
) do |http|
request = Net::HTTP::Post.new(url, headers)
request_body = payload.to_json
request.body = request_body
http.request(request) do |response|
if response.code.to_i != 200
Rails.logger.error(
"HuggingFaceTextGeneration: status: #{response.code.to_i} - body: #{response.body}",
)
raise CompletionFailed
end
log =
AiApiAuditLog.create!(
provider_id: AiApiAuditLog::Provider::HuggingFaceTextGeneration,
raw_request_payload: request_body,
user_id: user_id,
)
if !block_given?
response_body = response.read_body
parsed_response = JSON.parse(response_body, symbolize_names: true)
log.update!(
raw_response_payload: response_body,
request_tokens: tokenizer.size(prompt),
response_tokens: tokenizer.size(parsed_response.first[:generated_text]),
)
return parsed_response
end
response_data = +""
begin
cancelled = false
cancel = lambda { cancelled = true }
response_raw = +""
response.read_body do |chunk|
if cancelled
http.finish
return
end
response_raw << chunk
chunk
.split("\n")
.each do |line|
data = line.split("data:", 2)[1]
next if !data || data.squish == "[DONE]"
if !cancelled
begin
# partial contains the entire payload till now
partial = JSON.parse(data, symbolize_names: true)
# this is the last chunk and contains the full response
next if partial[:token][:special] == true
response_data << partial[:token][:text].to_s
yield partial, cancel
rescue JSON::ParserError
nil
end
end
end
rescue IOError
raise if !cancelled
ensure
log.update!(
raw_response_payload: response_raw,
request_tokens: tokenizer.size(prompt),
response_tokens: tokenizer.size(response_data),
)
end
end
return response_data
end
end
def self.try_parse(data)
JSON.parse(data, symbolize_names: true)
rescue JSON::ParserError
nil
end
end
end
end
end