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Querying offline Sanity datasets with GROQ

Did you know you can query your .ndjson files from Sanity dataset exports with GROQ? Check this out:

Initial motivation

I wanted to explore the idea of letting users query backup data in the Baccup application, and started by exploring what the ndjson format really was. Turns out, it’s really simple. It’s just a giant JSON array, except objects in that array are separated by a newline. ndjson stands for newline-delimited JSON.

That got me thinking, it would be trivial to do a sort of “object visualizer”, where each object (which would have an arbitrary schema) could be represented visually and queried. I was probably thinking about my experience working with MongoDB at that point. I could then possibly create a GraphQL-like query language to query these objects and create some sort of filter function to explore the dataset.

Aren’t you just reinventing GROQ?

If you got here in the previous paragraph, you’re smarter than me (low bar). After I made that connection, I looked up GROQ and turns out, there’s a specification document. TLDR, I learned that it’s a query language to query any JSON document (read: not just Sanity ones) and best of all, just when I thought I wanted to work on my own GROQ implementation in TypeScript, I discovered groq-js already exists.

(I told you the bar was low. )

From here, it’s just about creating an interface where you could select any .ndjson file and run the groq-js library against it. Check it out. Or if you want to try running GROQ queries against any JSON object input, check out groq.dev.

Insights/lightbulb moments

  • GROQ works with any JSON input, not just Sanity dataset exports. This gave me the idea of creating a minimalist CMS that runs on just a .json file, and where the query language is still GROQ.
  • With an assets-included Sanity dataset export, asset entries are included simiar to this: image@file://./images/379904115c36fd84f7b1e996188b5bccc7e9662f-150x150.jpg. This maps neatly to the assets folder in the same export.
  • Looking at .ndjson files gave me the idea of portable websites that could run completely offline with a sort of lightweight GROQ client, but keeping Sanity as the CMS/content-editing experience.
  • we could plausibly create entire ‘point-in-time’ website snapshots with a little engineering.

Credit where it’s due

Sanity has released the GROQ spec and tools to work with it, so it was really easy to connect the dots and put all this together. I can only imagine the powerful tools we could create for the Sanity community. Definitely excited to experiment more in this area.