ParsePort

A killswitch for Parse. Have your app talk to your servers instead when you outgrow Parse, all without shipping a new binary or changing a line of code.

IMPORTANT! This swizzles a private Parse API and could break with any new release of the
Parse SDK. If it does, please open an issue so I know to fix it.

Parse is an incredible platform that removes a lot of headache for building backend services for your apps. As great as Parse is, using it unfortunately locks you into their platform in perpetuity, i.e. As long as you have users in the wild with app binaries using the Parse SDK you're stuck with Parse.

There are a number of reasons for wanting to avoid vendor lock in including:

• Parse is great today, but there are no guarantees the same team will be there in the future delivering a service of the same quality.

• Parse can change their pricing at anytime making it catastrophically expensive for your app overnight.

• Parse or its owner Facebook could begin to abuse their priveleged access to all Parse app metrics to act anti-competitively, e.g. by using the information unfairly in M&A. For more on this see http://swaggadocio.com/post/60416244109

Usage

When you first use ParsePort you'll be happy for your app to use Parse, but ParsePort allows you to build in the flexibility to leave Parse later without cutting a new app binary. A good strategy is to pair ParsePort with GroundControl by the prolific Mattt Thompson,

Client code

In your application delegate application:didFinishLaunchingWithOptions method:

#import <ParsePort.h>

NSString * const kParsePortURL = @"parsePortURL"

NSURL *URL = [NSURL URLWithString:@"http://example.com/defaults.plist"];

[[NSUserDefaults standardUserDefaults] registerDefaultsWithURL:URL];

NSURL * parsePortURL = [[[NSUserDefaults] standardUserDefaults]]
                                          URLForKey:kParsePortURL];
                                          
if(parsePortURL) [ParsePort useURL:[NSURL URLWithString:parsePortURL]];

Server Code

The following Sinatra app will force the Parse SDK to talk to your servers without having to release a new app binary.

require 'sinatra'
require 'plist'

get '/defaults.plist' do
  content_type 'application/x-plist'

  { parsePortURL: 'http://api.example.com/' }.to_plist
end

Caveats

This is only the client portion of a Parse migration. In true lean fashion I haven't built the server component because I don't need it yet; I'm very happy with Parse but the peace of mind knowing I have the option of a simpler migration should the need arise makes me sleep easier at night.

If the time comes when I need to move apps from Parse, I would start by looking at Helios (again by Mattt), and use some Rack middleware to make any mappings.

Contact

@stevegraham