Recently I developed with Alexander Zeh an interface for an Android tablet app for the agents in an African mobile payment network. It was a pitch for the company, and while we weren’t selected we’re quite happy with our work and decided to share it with you. You can find our designs and analysis at http://bubblefoundry.com/tabletinterface/.
Oh. my. god. What a giant disaster.
I’ve been raving about how awesome Tropo is at handling SMSes to everyone I talk to, but no more. Tropo expects EVERY interaction to be the in the form of a response to a request that they’ve POSTed to your API endpoint.
Everything is part of a session THROUGH THEIR SERVER AND BACK TO YOUR CALLBACK URL. Want to send an SMS? First you need to create a session. Consider the Java library (in Scala):
val result = api.launchSession(token) if (result.getSuccess) { api.message(...) ... } |
All valid, type-safe code. launchSession() returns a TropoLaunchResult, which indicates whether the session was successfully created and, if so, its session id.
We can work with this, right? WRONG! As part of the session creation Tropo will throw a session creation object at your callback URL:
00020 0000 11:22:41 PM ApplicationInstance[http://miogiro.pr1001.cloudbees.net/tropo.json , sas_2-15-sm1778xfp7g8g0dtropo] starts execution on Thread Tropo-Thread-3899e36f1ad7650f2848c3ac12332b96
00021 0000 11:22:41 PM Thread Tropo-Thread-3899e36f1ad7650f2848c3ac12332b96 acquired engine com.tropo.rest.engine.TropoScriptEngine@78ded0e7 of type tropo-web, activeEngines = 4
00022 0000 11:22:41 PM Sending TropoML Payload on Tropo-Thread-3899e36f1ad7650f2848c3ac12332b96 [url=http://miogiro.pr1001.cloudbees.net/tropo.json]: {"session":{"id":"3899e36f1ad7650f2848c3ac12332b96","accountId":"notsharing","timestamp":"2011-12-09T23:22:41.612Z","userType":"NONE","initialText":null,"callId":null,"parameters":{"token":"notsharing","action":"create"}}}
00023 0000 11:22:41 PM Received non-2XX status code on Tropo-Thread-3899e36f1ad7650f2848c3ac12332b96 [url=http://miogiro.pr1001.cloudbees.net/tropo.json, code=500]
00024 0000 11:22:41 PM Thread Tropo-Thread-3899e36f1ad7650f2848c3ac12332b96 returned engine com.tropo.rest.engine.TropoScriptEngine@78ded0e7 of type tropo-web, activeEngines = 3
00025 0000 11:22:41 PM ApplicationInstance[http://miogiro.pr1001.cloudbees.net/tropo.json , sas_2-15-sm1778xfp7g8g0dtropo] ends execution on Thread Tropo-Thread-3899e36f1ad7650f2848c3ac12332b96
00026 0000 11:22:41 PM sas_2-15-sm1778xfp7g8g0dtropo invalidated
00027 0000 11:22:41 PM Instance 3899e36f1ad7650f2848c3ac12332b96 removed
See what’s happening? If you fail to handle it and return a 200 status code (and a Tropo JSON verb?) it kills the session, never mind that I have no need for that. That means it’s literally impossible to send an SMS without a server setup to receive callback messages from Tropo. Oh, and of course you can only specify one URL: you’re supposed to route all the different requests based upon extra parameters you stick in the session creation requests.
It literally boggles the mind how someone could have thought this was a good idea.
Tropo, if you want to fix this and need help send me an email at peter@bubblefoundry.com. Tropo competitors, if you have a sane API to send SMS messages and callbacks to response to received messages (bonus points for a Scala or even Java library) and provide UK numbers that can handle both inbound and outbound SMS, feel free also to email me at peter@bubblefoundry.com.
Daniel Salber and I will be giving the next Appsterdam Weekly Wednesday Lecture on mobile APIs. The talk is on Wednesday July 27 at 12:30 at Vijzelstraat 20, Amsterdam.
Here is our talk description:
Many mobile apps get data or send data to a server. What are the issues in implementing this kind of apps? In this talk, Peter Robinett and Daniel Salber will share their personal experiences designing and implementing both the server and client (iOS) sides of APIs for mobile apps, taking examples from their apps Smakelijk Amsterdam, Coffeeshoppr, iFebo, and JHM. Starting from questions to ask at the beginning of a project, continuing all the way through to debugging and performance, they will lead you through a broad overview of the implementation of a mobile API in your project.
If you do it right, your customers will become your best salespeople.
Android G1 Box from Alper Çugun on Vimeo.
For those interested in better understand web design, I highly recommend the article “Understanding Web Design” in A List Apart. In the piece Jeffrey Zeldman make a convincing case for the uniqueness of web design and draws an interesting analogy to typography.