Rafael dos Santos Silva 2c0f535bab
FEATURE: HyDE-powered semantic search. (#136)
* FEATURE: HyDE-powered semantic search.

It relies on the new outlet added on discourse/discourse#23390 to display semantic search results in an unobtrusive way.

We'll use a HyDE-backed approach for semantic search, which consists on generating an hypothetical document from a given keywords, which gets transformed into a vector and used in a asymmetric similarity topic search.

This PR also reorganizes the internals to have less moving parts, maintaining one hierarchy of DAOish classes for vector-related operations like transformations and querying.

Completions and vectors created by HyDE will remain cached on Redis for now, but we could later use Postgres instead.

* Missing translation and rate limiting

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Co-authored-by: Roman Rizzi <rizziromanalejandro@gmail.com>
2023-09-05 11:08:23 -03:00

35 lines
878 B
Ruby

# frozen_string_literal: true
module DiscourseAi
module Embeddings
module HydeGenerators
class Llama2 < DiscourseAi::Embeddings::HydeGenerators::Base
def prompt(search_term)
<<~TEXT
[INST] <<SYS>>
You are a helpful bot
You create forum posts about a given topic
<</SYS>>
Topic: #{search_term}
[/INST]
Here is a forum post about the above topic:
TEXT
end
def models
["Llama2-*-chat-hf"]
end
def hypothetical_post_from(query)
::DiscourseAi::Inference::HuggingFaceTextGeneration.perform!(
prompt(query),
SiteSetting.ai_embeddings_semantic_search_hyde_model,
token_limit: 400,
).dig(:generated_text)
end
end
end
end
end