rethink-filter-parser

RethinkDB filter parser

This is pretty experimental, and mostly for my own edification. It turns simple lambdas into ReQL, for no good reason, other than to give a sort of C# style interface. Half the things you should be able to do aren't implemented yet. Also, it converts the function to a string then parses it, so it'll bork on a wide variety of otherwise reasonable-looking functions.

Installation

$ npm install --save rethink-filter-parser

Usage

Import and use.

import parser from 'rethink-filter-parser';
 
// ...
 
r.table('people').filter(parser((x) => x.age > 18))
// equivalent to r.table('people').filter(r.row('age').gt(18))

Note that the choice of the name x to stand for the row is arbitrary: it could be called something else, as long as there is exactly one argument.

The 'preferred' way is to use rethink-plus:

import parser from 'rethink-filter-parser';
import RethinkPlus from 'rethink-plus';
 
let db = new RethinkPlus({plugins: [parser.plugin]});
let adults = await db.table.people.filter((x) => x.age > 16);

You can add context to use within your lambda - the 2nd argument can be referred to by ctx:

let people = await db.table.people.filter((x) => x.age > ctx, minAge);

If you pass an object, the fields are accessible just by name:

let people = await db.table.people.filter((x) => x.age > minAge, {minAge});

Note that the lambda is parsed, not run, and so it can't 'see' other variables in the scope: hence the context parameter.

Finally, if you're stuck without lambdas, you can use a good old-fashioned function, as long as it only has one statement and it begins with return:

db.table.people.filter(function (x) { return x.age > minAge; }, {minAge})

That sort of defeats the point though...

Licence etc

ISC licence, do what you like. It's pretty much only half-written, so if you're interested in this project get in touch and I'll make an effort to finish it!