@acusti/parsing

@acusti/parsing exports parseAsJSON, a function that takes a string and attempts to parse it as JSON, returning the resulting JS value, or null if the string defeated all attempts at parsing it. This is especially useful for generative AI when you prompt an LLM to generate a response in JSON, because most models are unable to consistently generate valid JSON, and even when they do, will often have a pre- or post-amble as a part of the response.

The unit tests show the kinds of LLM responses and syntax errors that the package can fix and convert into a valid result.

Usage

npm install @acusti/parsing
# or
yarn add @acusti/parsing

Import parseAsJSON (it’s a named export) and pass a string to it:

import { parseAsJSON } from '@acusti/parsing';

// it might neglect to close the outer curly braces
parseAsJSON(`  Sure, here's an example of a JSON response for the "Contact Form" page:
{
    "heading": "Get in Touch",
    "form": {
        "email": "[e-mail]",
        "message": "Please enter your message or inquiry below"
    }
`);
/* results in:
{
    heading: 'Get in Touch',
    form: {
        email: '[e-mail]',
        message: 'Please enter your message or inquiry below',
    },
}
*/

// you might get a "key": "value" list with no syntax around it
parseAsJSON(` Here are the props for the "Blog" page:
Props:
"blogPostImage1": "/images/blog-post-image1.jpg",
"blogPostSubheading1": "Exploring the Art of Sourdough Baking",
"blogPostHeading1": "The Magic of Sourdough",
"blogPostLede1": "At Masa Madre, we're passionate about creating the perfect sourdough bread. Learn more about the art and craft of this ancient tradition.",
"blogPostImage2": "/images/blog-post-image2.jpg",
"blogPostSubheading2": "From Seed to Loaf",
"blogPostHeading2": "Our Journey to Your Table",
"blogPostLede2": "Discover the journey of our sourdough bread, from the seed to the loaf.",
"blogPostImage3": "/images/blog-post-image3.jpg",
"blogPostSubheading3": "Sourdough 101",
"blogPostHeading3": "Learn the Basics of Artisanal Bread Making",
"blogPostLede3": "Get started on your sourdough journey with our beginner's guide to artisanal bread making.",
`);
/* results in:
{
    blogPostImage1: '/images/blog-post-image1.jpg',
    blogPostSubheading1: 'Exploring the Art of Sourdough Baking',
    blogPostHeading1: 'The Magic of Sourdough',
    blogPostLede1: "At Masa Madre, we're passionate about creating the perfect sourdough bread. Learn more about the art and craft of this ancient tradition.",
    blogPostImage2: '/images/blog-post-image2.jpg',
    blogPostSubheading2: 'From Seed to Loaf',
    blogPostHeading2: 'Our Journey to Your Table',
    blogPostLede2: 'Discover the journey of our sourdough bread, from the seed to the loaf.',
    blogPostImage3: '/images/blog-post-image3.jpg',
    blogPostSubheading3: 'Sourdough 101',
    blogPostHeading3: 'Learn the Basics of Artisanal Bread Making',
    blogPostLede3: "Get started on your sourdough journey with our beginner's guide to artisanal bread making.",
}
*/

// in case llama 2 decides to give you a markdown table to represent the JSON
parseAsJSON(`Here are the props for Vytas' Hatha Yoga classes:
Props:
| Prop Name | Value |
| blogPostImage1 | /vytas-yoga-class-background.jpg |
| shortBlogPostCaption1 | "Find inner peace and balance through physical postures and breathing techniques" |
| blogPostHeading1 | "Hatha Yoga Classes with Vytas" |
| miniBlogPostLede1 | "Discover the transformative power of Hatha Yoga with Vytas, a seasoned yoga teacher" |
| blogPostImage2 | /vytas-yoga-community-background.jpg |
| shortBlogPostCaption2 | "Join a supportive community of like-minded individuals and deepen your practice with Vytas" |
| blogPostHeading2 | "Community and Connection" |
| miniBlogPostLede2 | "Vytas' Hatha Yoga classes offer a sense of community and connection" | |`);
/* results in:
{
    'Prop Name': 'Value',
    blogPostImage1: '/vytas-yoga-class-background.jpg',
    shortBlogPostCaption1: 'Find inner peace and balance through physical postures and breathing techniques',
    blogPostHeading1: 'Hatha Yoga Classes with Vytas',
    miniBlogPostLede1: 'Discover the transformative power of Hatha Yoga with Vytas, a seasoned yoga teacher',
    blogPostImage2: '/vytas-yoga-community-background.jpg',
    shortBlogPostCaption2: 'Join a supportive community of like-minded individuals and deepen your practice with Vytas',
    blogPostHeading2: 'Community and Connection',
    miniBlogPostLede2: "Vytas' Hatha Yoga classes offer a sense of community and connection",
}
*/

// it might prematurely close the outer JSON object even though the content continues
parseAsJSON(
    '```json\n{"heading":"Organic Produce","subheading":"The Benefits of Going Organic","description":"Organic produce is grown without the use of synthetic pesticides, herbicides, or fertilizers."},"items":[{"heading":"Organic Fruits","subheading":"Nature\'s Sweet Treats"},{"heading":"Organic Vegetables","subheading":"Fresh from the Garden"}]}\n```',
);
/* results in:
{
    heading: 'Organic Produce',
    subheading: 'The Benefits of Going Organic',
    description: 'Organic produce is grown without the use of synthetic pesticides, herbicides, or fertilizers.',
    items: [
        {
            heading: 'Organic Fruits',
            subheading: "Nature's Sweet Treats",
        },
        {
            heading: 'Organic Vegetables',
            subheading: 'Fresh from the Garden',
        },
    ],
}
*/

Again, there are more examples of the kinds of things that the parser can handle in the unit tests.

Also, if you’re wondering the best way to get an LLM to return JSON, I found the few-shot prompting approach suggested in Pinecone’s Llama 2: AI Developers Handbook helpful with a variety of different models (Llama 2 7B, OpenChat 3.5, OpenHermes 2.5, Zephyr 7B).