discourse-ai/lib/completions/endpoints/aws_bedrock.rb

107 lines
3.1 KiB
Ruby

# frozen_string_literal: true
require "aws-sigv4"
module DiscourseAi
module Completions
module Endpoints
class AwsBedrock < Base
def self.can_contact?(model_name)
%w[claude-instant-1 claude-2].include?(model_name) &&
SiteSetting.ai_bedrock_access_key_id.present? &&
SiteSetting.ai_bedrock_secret_access_key.present? &&
SiteSetting.ai_bedrock_region.present?
end
def normalize_model_params(model_params)
model_params = model_params.dup
# temperature, stop_sequences are already supported
#
if model_params[:max_tokens]
model_params[:max_tokens_to_sample] = model_params.delete(:max_tokens)
end
model_params
end
def default_options
{ max_tokens_to_sample: 3_000, stop_sequences: ["\n\nHuman:", "</function_calls>"] }
end
def provider_id
AiApiAuditLog::Provider::Anthropic
end
private
def model_uri
# Bedrock uses slightly different names
bedrock_model_id = model.split("-")
bedrock_model_id[-1] = "v#{bedrock_model_id.last}"
bedrock_model_id = bedrock_model_id.join("-")
api_url =
"https://bedrock-runtime.#{SiteSetting.ai_bedrock_region}.amazonaws.com/model/anthropic.#{bedrock_model_id}/invoke"
api_url = @streaming_mode ? (api_url + "-with-response-stream") : api_url
URI(api_url)
end
def prepare_payload(prompt, model_params, _dialect)
default_options.merge(prompt: prompt).merge(model_params)
end
def prepare_request(payload)
headers = { "content-type" => "application/json", "Accept" => "*/*" }
signer =
Aws::Sigv4::Signer.new(
access_key_id: SiteSetting.ai_bedrock_access_key_id,
region: SiteSetting.ai_bedrock_region,
secret_access_key: SiteSetting.ai_bedrock_secret_access_key,
service: "bedrock",
)
Net::HTTP::Post
.new(model_uri)
.tap do |r|
r.body = payload
signed_request =
signer.sign_request(req: r, http_method: r.method, url: model_uri, body: r.body)
r.initialize_http_header(headers.merge(signed_request.headers))
end
end
def decode(chunk)
Aws::EventStream::Decoder
.new
.decode_chunk(chunk)
.first
.payload
.string
.then { JSON.parse(_1) }
.dig("bytes")
.then { Base64.decode64(_1) }
rescue JSON::ParserError,
Aws::EventStream::Errors::MessageChecksumError,
Aws::EventStream::Errors::PreludeChecksumError => e
Rails.logger.error("#{self.class.name}: #{e.message}")
nil
end
def extract_completion_from(response_raw)
JSON.parse(response_raw, symbolize_names: true)[:completion].to_s
end
def partials_from(decoded_chunk)
[decoded_chunk]
end
end
end
end
end