index.ts•4.01 kB
/**
* Copyright 2024 Google LLC
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
import { gemini15Flash, googleAI } from '@genkit-ai/googleai'; // Import specific plugins/models for generative AI
import * as fs from 'fs/promises'; // Import file system promises for reading files
import { genkit, z } from 'genkit'; // Import Genkit framework and Zod schema validation
import { logger } from 'genkit/logging'; // Import logger for debugging and logging
// If using Node.js <18:
// import fetch from 'node-fetch'; // Install this if `fetch` is not natively available.
const ai = genkit({
plugins: [googleAI()], // Initialize Genkit with Google AI plugin
});
logger.setLogLevel('debug'); // Set logging level to debug for detailed logs
export const warAndPeaceFlow = ai.defineFlow(
{
name: 'warAndPeaceFlow', // Define a unique name for this flow
inputSchema: z.object({
query: z.string().optional(), // Define user input schema for query, optional string
textFilePath: z.string().optional(), // Define schema for the text file path, optional string
}),
outputSchema: z.string(), // Define the expected output schema, a string
},
async ({ query, textFilePath }) => {
const defaultQuery =
"Describe Pierre Bezukhov's transformation throughout the novel."; // Default query if the user doesn't provide one
let textContent;
if (textFilePath) {
// Read the content from the provided file path
textContent = await fs.readFile(textFilePath, 'utf-8');
} else {
// Fetch the default content from the provided link
const response = await fetch(
'https://www.gutenberg.org/cache/epub/2600/pg2600.txt'
);
if (!response.ok) {
const errMsg = (await response.json()).error?.message || '';
throw new Error(
`Failed to fetch default text content: ${response.statusText}. ${errMsg}`
);
}
textContent = await response.text();
}
// Generate a response using AI with the following parameters
const llmResponse = await ai.generate({
messages: [
{
role: 'user', // User message providing context or query
content: [{ text: textContent }], // Include the loaded text content as an array of parts
},
{
role: 'model', // Model's response to the user's query
content: [
{
text: 'Here is some analysis based on the text provided.',
},
],
metadata: {
cache: {
ttlSeconds: 300, // Cache TTL for this specific response
},
},
},
],
config: {
version: 'gemini-1.5-flash-001', // Specify the model version
temperature: 0.7, // Control randomness in the output
maxOutputTokens: 1000, // Limit the maximum number of tokens for the response
topK: 50, // Limit token selection to top K probabilities
topP: 0.9, // Apply nucleus sampling with 0.9 threshold
stopSequences: ['END'], // Define custom sequences to stop the generation
},
tools: [], // No tools used in this request
model: gemini15Flash, // Specify the generative model to use
prompt: query || defaultQuery, // Use user's query or default query for the main task
returnToolRequests: false, // Prevent tool requests from being returned automatically
});
return llmResponse.text; // Return the generated response text
}
);