object-cache-graph-thing

A thing for making object traversals quicker

Object traversals are slow, recursion is not fun, and waiting 10s for a page to load because you have to parse a JSON blob 17 times is terrible. This tries to fix some of that.

Instead of trying ot recursively search an object to find all children that match a pattern, let's only search it once, construct a graph of all instances of the thing we care about, and manipulate that graph.

Example:

import ObjectCache from 'object-cache-graph-thing';
 
const objectThatICareAbout = {
    a: [
        { foo: true },
        { foo: false, c: { foo: true } }
    ]
    b: { foo: true }
}
 
// Find all objects that have a property `foo`
// The predicate function returns what to store for a given path in the object
// If a falsy value is returned, then that path is ignored and not cached.
const predicate = (testObj) => _.isObject(testObj) && _.has(testObj, 'foo') && foo
 
const cache = new ObjectCache(objectThatICareAbout, predicate);
 
 
// Get all the paths where `foo` is a prop
cache.getPaths(); // [ ['a', 0], ['a', 1], ['a', 1, 'c'], ['b'] ]
 
// Get a sub-graph relative to child
// same as new `ObjectCache(objectThatICareAbout.a, predicate)`, without the overhead of parsing again
cache.getCacheForPath(['a']);
 

API

import ObjectCache from 'object-cache-graph-thing';

ObjectCache instances

Methods

ObjectCache.prototype.constructor(seedObject : Object, predicate : Function)

Constructs a new ObjectCache instance

ObjectCache.prototype.getCacheForValue(val : Any)

Create a new ObjectCache instance for the given value

ObjectCache.prototype.getCacheForPath(path: Array)

Create a new ObjectCache instance for the given subtree

ObjectCache.prototype.getPaths()

Get all the current paths in the tree

ObjectCache.prototype.getValues()

Get all the current values in the tree