Engage-cordova-plugin-firestore NPM

Cordova Firestore Plugin

A Google Firebase Firestore plugin to enable realtime synchronisation between app and cloud and automatically handle limited connectivity.

What is Firestore?

From the Google documentation (https://firebase.google.com/docs/firestore/):

Cloud Firestore is a flexible, scalable database for mobile, web, and server development from Firebase and Google Cloud Platform. Like Firebase Realtime Database, it keeps your data in sync across client apps through realtime listeners and offers offline support for mobile and web so you can build responsive apps that work regardless of network latency or Internet connectivity. Cloud Firestore also offers seamless integration with other Firebase and Google Cloud Platform products, including Cloud Functions

Supported platforms

This plugin supports the following platforms:

Android
iOS
Browser

Installation

cordova plugin add cordova-plugin-firestore --variable ANDROID_FIREBASE_VERSION=11.8.0 --save

phonegap plugin add cordova-plugin-firestore --variable ANDROID_FIREBASE_VERSION=11.8.0

Omitting FIREBASE_VERSION will use a default value.

Dependencies

Promises

This plugin uses Promises. If you want to use this with Android 4.4 then you will need to include a Promise polyfill.

Firebase configuration

Android

You must ensure that google-services.json is put in the correct location. This can be achieved using the following in your config.xml:

<platform name="android">
    <resource-file src="google-services.json" target="google-services.json" />
</platform>

Dependencies

cordova-support-google-services

In order to ensure Firebase initialises correctly on Android this plugin can be used. This is not automatically added as a dependency to allow for the configuration it performs to be done manually if desired.

iOS

iOS requires GoogleService-Info.plist is put in the correct location. Similarly this can be done as follows:

<platform name="ios">
    <resource-file src="GoogleService-Info.plist" />
</platform>

Keychain Sharing Capability

If using multiple Firebase plugins it may be necessary to enable this.

What is supported?

Firestore

collection()
runTransaction(updateFunction)

DocumentSnapshot

data()
get(fieldPath)
exists
id
ref

QuerySnapshot

docs
empty
size

DocumentReference

delete()
get()
onSnapshot(optionsOrObserverOrOnNext, observerOrOnNextOrOnError, onError)
set(data, options)
update(data)
id
parent

Query

endAt(snapshotOrVarArgs)
endBefore(snapshotOrVarArgs)
limit(limit)
orderBy(field, direction)
get()
onSnapshot(callback, options)
startAfter(snapshotOrVarArgs)
startAt(snapshotOrVarArgs)
where(fieldPath, opStr, passedValue)

CollectionReference (inherits from Query)

add(data)
id
doc(id)

Transaction

get()
delete()
set()
update()

FieldValue

FieldValue.delete()
FieldValue.serverTimestamp()

Initialisation

The plugin can be initialised as follows:

      var options = {
        datePrefix: '__DATE:',
        "fieldValueDelete": "__DELETE",
        "fieldValueServerTimestamp" : "__SERVERTIMESTAMP",
        "persist": true
      };

      if (cordova.platformId === "browser") {

        options.browser = {
          apiKey: 'my API key',
          authDomain: 'my domain',
          projectId: 'my project id',
        };
      }

      Firestore.initialise(options).then(function(database) {
        myDatabaseReference = database;
      });
    });

This is initialised as a promise to allow the Browser implementation to dynamically add a reference to the Firestore Javascript SDK.

Dates

Because data is transferred to the client as JSON there is extra logic in place to handle the conversion of dates for some operations.

When initialising the plugin you can set up a prefix that is applied to a string value which is used to identify it as a date. The default prefix is __DATE:

Therefore, when a date field is retrieved from the database by the native code it will be transferred in the JSON looking similar to the following:

{
    "dateField" : "__DATE:123456789"
}

The number is seconds since epoch.

The client will receive the field as a Javascript Date.

This conversion also happens when specify a field in a where condition.

FieldValue constants

Similar to the situation with dates, there are special values used for FieldValue values:

FieldValue.delete() equates to __DELETE
FieldValue.serverTimestamp() equates to __SERVERTIMESTAMP

These values can be changed when initialisation is performed.

Learnings and notes

I have learnt a number of things whilst implementing this:

The documentation states that the database cannot be initialised in a seperate thread when using persistence. In my experience this should say it cannot be used in multiple threads.
When used on Android ensure that at least com.google.gms:google-services:3.1.1 is used in build dependencies. Earlier versions did not work for me.
Yes, I did spell initialise() with an 's' - I am from the UK