llama-stack-mirror/llama_stack/core/prompts/prompts.py

# Copyright (c) Meta Platforms, Inc. and affiliates.
# All rights reserved.
#
# This source code is licensed under the terms described in the LICENSE file in
# the root directory of this source tree.

import json
from typing import Any

from pydantic import BaseModel

from llama_stack.apis.prompts import ListPromptsResponse, Prompt, Prompts
from llama_stack.providers.utils.kvstore import KVStore, kvstore_impl
from llama_stack.providers.utils.kvstore.config import KVStoreConfig


class PromptServiceConfig(BaseModel):
    """Configuration for the built-in prompt service.

    :param kvstore: Configuration for the key-value store backend
    """

    kvstore: KVStoreConfig


async def get_provider_impl(config: PromptServiceConfig, deps: dict[Any, Any]):
    """Get the prompt service implementation."""
    impl = PromptServiceImpl(config, deps)
    await impl.initialize()
    return impl


class PromptServiceImpl(Prompts):
    """Built-in prompt service implementation using KVStore."""

    def __init__(self, config: PromptServiceConfig, deps: dict[Any, Any]):
        self.config = config
        self.deps = deps
        self.kvstore: KVStore

    async def initialize(self) -> None:
        self.kvstore = await kvstore_impl(self.config.kvstore)

    def _get_prompt_key(self, prompt_id: str, version: str | None = None) -> str:
        if version:
            return f"prompts:v1:{prompt_id}:{version}"
        return f"prompts:v1:{prompt_id}:default"

    def _get_version_key(self, prompt_id: str, version: str) -> str:
        """Get the KVStore key for a specific prompt version."""
        return f"prompts:v1:{prompt_id}:{version}"

    def _get_list_key_prefix(self) -> str:
        """Get the key prefix for listing prompts."""
        return "prompts:v1:"

    def _serialize_prompt(self, prompt: Prompt) -> str:
        """Serialize a prompt to JSON string for storage."""
        return json.dumps(
            {
                "prompt_id": prompt.prompt_id,
                "prompt": prompt.prompt,
                "version": prompt.version,
                "variables": prompt.variables or {},
            }
        )

    def _deserialize_prompt(self, data: str) -> Prompt:
        """Deserialize a prompt from JSON string."""
        obj = json.loads(data)
        return Prompt(
            prompt_id=obj["prompt_id"], prompt=obj["prompt"], version=obj["version"], variables=obj.get("variables", {})
        )

    async def list_prompts(self) -> ListPromptsResponse:
        """List all prompts (default versions only)."""
        prefix = self._get_list_key_prefix()
        keys = await self.kvstore.keys_in_range(prefix, prefix + "\xff")

        prompts = []
        for key in keys:
            if key.endswith(":default"):
                try:
                    default_version = await self.kvstore.get(key)
                    if default_version:
                        prompt_id = key.replace(prefix, "").replace(":default", "")
                        version_key = self._get_version_key(prompt_id, default_version)
                        data = await self.kvstore.get(version_key)
                        if data:
                            prompt = self._deserialize_prompt(data)
                            prompts.append(prompt)
                except (json.JSONDecodeError, KeyError):
                    continue

        prompts.sort(key=lambda p: p.prompt_id or "", reverse=True)
        return ListPromptsResponse(data=prompts)

    async def get_prompt(self, prompt_id: str, version: str | None = None) -> Prompt:
        """Get a prompt by its identifier and optional version."""
        if version:
            key = self._get_version_key(prompt_id, version)
            data = await self.kvstore.get(key)
            if data is None:
                raise ValueError(f"Prompt {prompt_id} version {version} not found")
        else:
            default_key = self._get_prompt_key(prompt_id)
            default_version = await self.kvstore.get(default_key)
            if default_version is None:
                raise ValueError(f"Prompt with ID '{prompt_id}' not found")

            key = self._get_version_key(prompt_id, default_version)
            data = await self.kvstore.get(key)
            if data is None:
                raise ValueError(f"Prompt with ID '{prompt_id}' not found")

        return self._deserialize_prompt(data)

    async def create_prompt(
        self,
        prompt: str,
        variables: dict[str, str] | None = None,
    ) -> Prompt:
        """Create a new prompt."""
        if variables is None:
            variables = {}

        prompt_obj = Prompt(prompt_id=Prompt.generate_prompt_id(), prompt=prompt, version="1", variables=variables)

        version_key = self._get_version_key(prompt_obj.prompt_id, "1")
        data = self._serialize_prompt(prompt_obj)
        await self.kvstore.set(version_key, data)

        default_key = self._get_prompt_key(prompt_obj.prompt_id)
        await self.kvstore.set(default_key, "1")

        return prompt_obj

    async def update_prompt(
        self,
        prompt_id: str,
        prompt: str,
        variables: dict[str, str] | None = None,
    ) -> Prompt:
        """Update an existing prompt (increments version)."""
        if variables is None:
            variables = {}

        current_prompt = await self.get_prompt(prompt_id)
        new_version = str(int(current_prompt.version) + 1)

        updated_prompt = Prompt(prompt_id=prompt_id, prompt=prompt, version=new_version, variables=variables)

        version_key = self._get_version_key(prompt_id, new_version)
        data = self._serialize_prompt(updated_prompt)
        await self.kvstore.set(version_key, data)

        default_key = self._get_prompt_key(prompt_id)
        await self.kvstore.set(default_key, new_version)

        return updated_prompt

    async def delete_prompt(self, prompt_id: str) -> None:
        """Delete a prompt and all its versions."""
        await self.get_prompt(prompt_id)

        prefix = f"prompts:v1:{prompt_id}:"
        keys = await self.kvstore.keys_in_range(prefix, prefix + "\xff")

        for key in keys:
            await self.kvstore.delete(key)

    async def set_default_version(self, prompt_id: str, version: str) -> Prompt:
        """Set which version of a prompt should be the default (latest)."""
        version_key = self._get_version_key(prompt_id, version)
        data = await self.kvstore.get(version_key)
        if data is None:
            raise ValueError(f"Prompt {prompt_id} version {version} not found")

        default_key = self._get_prompt_key(prompt_id)
        await self.kvstore.set(default_key, version)

        return self._deserialize_prompt(data)