Support both object and array syntax queries

- Support multiple parameters for querying, in both object and array syntax
- Change documentation to ES5 format

Author: rickerbh

README.md

@@ -307,21 +307,31 @@ Additionaly for elasticsearch6 the number of shards, number of replicas, the ref
 Use the `firestore` type to support Google's Firestore database, and store your KeyFile in a location accessible by your application.
 
 ```javascript
-const options = {
-  repository: {
-    type: 'firestore',
-    projectId: 'YOUR_PROJECT_ID',
-    keyFilename: '/path/to/keyfile.json',
-  },
-};
+    const options = {
+        repository: {
+            type: 'firestore',
+            projectId: 'YOUR_PROJECT_ID',
+            keyFilename: '/path/to/keyfile.json'
+        },
+    };
 ```
 
 ### Find Queries
 
-Find queries in Firestore are not compatible with MongoDb syntax. The query parameter passed to `find` or `findOne` should be an array with the separate query fields as individual elements, as they will be `apply`'d and passed to the `where` function on the `Query` object.
+Simple (equality comparison) find queries are supported by passing javascript objects as the query parameter, or more complex queries can be executed via nested arrays. In the case of multiple key/value pairs or nested arrays, the composite predicates form logical ANDs.
 
 ``` javascript
-    aRepo.find(['aProp', '==', 'aValue'], (err, vm) => {
+    // Simple Object format
+    aRepo.find({'aProp': 'aValue', 'secondProp': 'secondValue'}, function (err, vm) {
+        if (err) {
+            console.log('Repo find error', err);
+            return;
+        }
+        console.log('Found', vm);
+    });
+
+    // Nested array syntax, allows for more complex predicates
+    aRepo.find([['aProp', '==', 'aValue'], ['secondProp', '<', 10000]], function (err, vm) {
         if (err) {
             console.log('Repo find error', err);
             return;

lib/databases/firestore.js

@@ -21,6 +21,24 @@ function implementError (callback) {
   throw err;
 }
 
+function parseFirestoreQuery(query) {
+  if (_.isArray(query)) {
+    return query;
+  } else if (_.isPlainObject(query)) {
+    return _.map(query, function(value, key) {
+      return [key, '==', value];
+    });
+  }
+  throw new Error('Unknown query type');
+};
+
+function firestoreQueryParser(collectionRef, queryParams) {
+  var params = parseFirestoreQuery(queryParams);
+  return _.reduce(params, function(acc, q) {
+    return acc.where.apply(acc, q);
+  }, collectionRef);
+}
+
 _.extend(Firestore.prototype, {
 
   connect: function (callback) {
@@ -72,14 +90,14 @@ _.extend(Firestore.prototype, {
   },
 
   find: function (queryParams, queryOptions, callback) {
+    // NOTE: queryOptions is ignored
+
     this.checkConnection();
 
-    // NOTE: Query should be an array, e.g., ['foo', '==', 'bar']
-    // queryOptions is ignored
     var self = this;
-
     var collectionRef = this.db.collection(this.collection);
-    var query = collectionRef.where.apply(collectionRef, queryParams);
+
+    var query = firestoreQueryParser(collectionRef, queryParams);
     query.get().then(function (querySnapshot) {
       var vms = _.map(querySnapshot.docs, function(documentSnapshot) {
         var vm = new ViewModel(documentSnapshot.data(), self);
@@ -90,13 +108,14 @@ _.extend(Firestore.prototype, {
     });
   },
 
-  findOne: function (query, queryOptions, callback) {
+  findOne: function (queryParams, queryOptions, callback) {
+    // NOTE: queryOptions is ignored
     this.checkConnection();
 
-    // NOTE: Query should be an array, e.g., ['foo', '==', 'bar']
     var self = this;
     var collectionRef = this.db.collection(this.collection);
-    var query = collectionRef.where.apply(collectionRef, query);
+
+    var query = firestoreQueryParser(collectionRef, queryParams);
     query.limit(1).get().then(function (querySnapshot) {
       if (querySnapshot.size == 0) {
         callback(null, null);