//building ruleConditions
var ruleConditions = {$and: []};

var fromConditions = mongoRequestsHelper.getFromConditions(rule.from);
if (fromConditions) ruleConditions.$and.push(fromConditions);

//and 4 similar blocks

if (mongoRequestsHelper.getFromConditions(rule.moversFilter)) ruleConditions.push(mongoRequestsHelper.getFromConditions(rule.moversFilter))

const clauses = [
    mongoRequestsHelper.getFromConditions(rule.A),
    mongoRequestsHelper.getFromConditions(rule.B),
    mongoRequestsHelper.getFromConditions(rule.C),
    mongoRequestsHelper.getFromConditions(rule.D),
    ......
];

const ruleConditions = {
    // filter out non-truthy clauses
    $and: clauses.filter(clause => clause)
};