index.js

var _ = require('underscore')

module.exports = {

    /**
     * Convert a mongodb query into an ES query
     * @param  {Object} q - the mongodb query
     * @return {Object} the ES query
     */
    // https://www.elastic.co/guide/en/elasticsearch/reference/current/query-filter-context.html
    convert: function(q) {

        console.log('query')
        console.log(JSON.stringify(q))

        // http://stackoverflow.com/questions/15690706/recursively-looping-through-an-object-to-build-a-property-list
        // recursively list the properties of this object
        var es = {
            query: {
                bool: {
                    must: [],
                    //should: []
                }
            }
        }

        es.query.bool.must.push({bool:{must:[]}})
        es.query.bool.must.push({bool:{should:[]}})
        //es.query.bool.should.push({bool:{must:[]}})
        //es.query.bool.should.push({bool:{should:[]}})

        var inAnd, inOr, inIn
        var inProps = []
        function iterate(obj) {
            for (var property in obj) {
                console.log('\n')
                if (obj.hasOwnProperty(property)) {
                    // operator
                    if (typeof obj[property] == "object" && (property == "$and" || obj[property].$and)) {
                        console.log('step1')
                        console.log(property)
                        console.log(obj[property])
                        inAnd = true
                        inOr = false
                        iterate(obj[property])
                    }
                    // operator
                    else if (typeof obj[property] == "object" && (property == "$or" || obj[property].$or)) {
                        console.log('step2')
                        console.log(property)
                        console.log(obj[property])
                        inOr = true
                        inAnd = false
                        iterate(obj[property])
                    }
                    // operator
                    else if (typeof obj[property] == "object" && (property == "$in" || obj[property].$in)) {
                        console.log('step3')
                        console.log(property)
                        console.log(obj[property])
                        inProps.push(property)
                        inIn = true
                        inOr = false
                        inAnd = false
                        iterate(obj[property])
                    }
                    // non-operator (a number index) ... could have operator inside though...
                    else if (typeof obj[property] == "object" && !obj[property].$and && !obj[property].$or && !obj[property].$in) {
                        var innerOperator = false
                        _.each(Object.keys(obj[property]), function(key) {
                            if (obj[property][key].$in || obj[property][key].$and || obj[property][key].$or) {
                                innerOperator = true
                            }
                        })
                        if (!innerOperator) {
                            console.log('step4')
                            console.log(property)
                            console.log(obj[property])
                            if (inAnd === true) {
                                console.log('step5 pushing: ' + JSON.stringify({match: obj[property]}))
                                es.query.bool.must[0].bool.must.push({match: obj[property]})
                            }
                            if (inOr === true) {
                                console.log('step7 pushing: ' + JSON.stringify({match: obj[property]}))
                                es.query.bool.must[1].bool.should.push({match: obj[property]})
                            }
                        }
                        else iterate(obj[property])
                    }
                    else if (inIn) {
                        var mq = {match:{}}
                        mq.match[inProps[0]] = obj[property]
                        console.log('step8 pushing: ' + JSON.stringify(mq))
                        es.query.bool.must[0].bool.must.push(mq)
                    }
                    else {
                        var mq = {match:{}}
                        mq.match[property] = obj[property]
                        console.log('step9 pushing: ' + JSON.stringify(mq))
                        es.query.bool.must[0].bool.must.push(mq)
                    }
                }
            }
        }

        iterate(q)

        console.log('result')
        console.log(JSON.stringify(es))

        return es
    }

};