pouchdb-selector-fun.js

// This is a follow on example from @bennadel blogpost https://www.bennadel.com/blog/3256-monkey-patching-the-mango-find-plugin-to-use-alldocs-in-pouchdb-6-2-0.htm
// This uses allDocs() with the keys selector to do a quick find for specific id's.
// It then uses pouchdb-selector-core to further filter the results. pouchdb-selector-core is the library that does the in-memory filtering
// for pouchdb-find and in the changes feed and with replication


// use pouchdb-browser here if you are running this in the browser
var PouchDB = require('pouchdb-node');
var selectors = require('pouchdb-selector-core');

const db = new PouchDB("doc-test");

const selector = {
  interests: {
    $in: ["Cooking"]
  }
};

db.bulkDocs([
  {
      _id: "friend:kim",
      name: "Kim",
      age: 42,
      interests: [ "Movies", "Computers", "Cooking" ],
      collection_friend: true
  },
  {
      _id: "friend:sarah",
      name: "Sarah",
      age: 35,
      interests: [ "Museums", "Working Out", "Movies" ],
      collection_friend: true
  },
  {
      _id: "friend:joanna",
      name: "Joanna",
      age: 29,
      interests: [ "Working Out", "Poetry", "Dancing" ],
      collection_friend: true
  },

  // Let's add some garbage documents as well in order to ensure that
  // our subsequent queries don't try to pull back more data that we
  // anticipate (ie, none of these documents should show up).
  {
      _id: "a",
      collection_garbage: true
  },
  {
      _id: "z",
      collection_garbage: true
  }
])
.then(resp => {
  return db.allDocs({include_docs: true, keys:["friend:kim", "friend:sarah"]})
})
.then(resp => {
  //This creates a new array of just the docs from allDocs and then filters it according to the selector
  const docs = resp.rows.map(row => row.doc).filter(doc => selectors.matchesSelector(doc, selector));
  console.log('Output', docs);

  //Have this here so we can just re-run the code without having to check if the initial docs are loaded
  return db.destroy();
})