Adapter-specific query leak in FeathersJS service pagination

Answer

Use a before hook on the service’s find method to filter or translate params.query before it reaches the adapter. This hook provides a single place to enforce a common query syntax and prevent adapter‑specific operators from leaking into your service layer.

Confirmed facts

• FeathersJS passes the raw params.query object directly to the underlying adapter; the framework does not insert a universal normalization layer.
• Official adapters (@feathersjs/sequelize, @feathersjs/mongoose, @feathersjs/knex) understand the standard FeathersJS query syntax ($limit, $skip, $sort, $select, $or, $gt, $lt, $in, etc.). Any unknown keys are forwarded unchanged, which allows adapter‑specific operators to leak.
• A before hook can inspect, remove, or map keys in context.params.query and then let the cleaned query continue to the adapter.

Steps to implement normalization

1. Create a hook function (e.g., normalizeQuery.js) that:
   • Defines a whitelist of allowed standard keys (including pagination and sorting).
   • Optionally maps known adapter‑specific operators to their standard equivalents (if you need to retain them).
   • Removes or transforms any keys not in the whitelist/map.
   • Preserves $limit, $skip, $sort to keep pagination intact.
2. Register the hook globally or per‑service:

   // app.hooks.js
   module.exports = {
     before: {
       find: [ normalizeQuery ]
     }
   };

3. Test the hook with a query that mixes standard and adapter‑specific keys to confirm the unwanted keys are stripped or translated as expected.

Missing diagnostic detail

Do you need to retain any adapter‑specific operators (e.g., Sequelize.Op.like, MongoDB $text) in your normalized query? If yes, you must extend the hook with a translation map; if no, a simple whitelist‑filter is sufficient.