Code Zen

Building CodeCoin: A Blockchain DApp prototype

If you know me, there is a good chance that you know how 👍 I am about Blockchain and Decentralized apps. I have given a few talks on it but till recently these were mostly either focused on Bitcoin or on the academics of Blockchain technology. At a recent Comcast Labweek, I was finally able to get my hands dirty with building a Blockchain based decentralized app (DApp) on Ethereum.

Labweek is a week long hackathon at the T&P org in Comcast that lets people work on pretty much anything. I was pretty fortunate to end up working with a bunch of really smart engineers here. The problem we decided to look into was the challenge of funding open source projects. I am pretty passionate about open source technologies but I have seen great ideas die on Github because supporting a project when you aren’t getting paid for it is really hard. Our solution to this problem was a bounty system for Github issues that we called CodeCoin.

The way CodeCoin worked was as follows:

A project using CodeCoin would sign up on our site and download some Git hooks.
When anyone creates an issue on Github, we create an Ethereum wallet for the issue and post the wallet address back to Github so its the first comment on the issue.
We use a Chrome extension that adds a “Fund this issue” button on the Github page that starts the Ethereum payment flow.
To actually handle the payment, we require MetaMask that we can trigger using its JavaScript api
Ether is held in the wallet till the issue is marked resolved and merged into master. At this time another Git hook fires that tells our server to release the Ether into the wallets of all the developers who worked on the issue.

Issue page design. Most of the UI changes came from a custom Chrome extension

Note that while we held the Ether on our side in wallets, the right way to do this would have been to use a Smart Contract. We started down that route but since most of the code was done in like 2 days (while juggling other real projects), wallets seemed like the easier route.

Releasing money into developer accounts was also a hack. Since developers don’t sign up to Github with any digital wallet address, we need the wallet addresses as part of the final commit message. This could be done with a lookup on a service like Keybase.IO maybe and with more time we would have tried integrating it to our prototype. In fact it was the next week that I heard about their own Git offering. I haven’t read enough about that yet though.

Development notes:

For local development, we used the TestRPC library to run a Ethereum chain simulation on our machine.
We used web3js, the Ethereum JavaScript api for doing most of the actual transactions
Web3js was injected into the browser by the MetaMask extension. There were some challenges getting Metamask to talk to the TestRPC. Basically, you had to make sure that you initialized MetaMask with the same seed words as you used for your account on TestRPC (which makes sense) but there isn’t a way afaik to change that information in MetaMask. Early on, we were restarting TestRPC without configuring the initial accounts so we’d have to reinstall MetaMask to configure it with the new account. Chalk that to our own unfamiliarity with the whole setup.

We did try to use Solidity to run a smart contract on TestRPC which worked for the demo apps, but canned that effort in the last moment as we were running out of time

All in all, it was a fun couple of days of intense coding and I feel I learnt a lot. Most of all I enjoyed working with a group of really smart peers, most of whom I didn’t know before the project at all. Hopefully we get to do more of that in the future 🙂

Notes from Oculus Connect 4

I had a great time last week attending Oculus Connect 4. Just like last year, the keynotes were really interesting and the sessions pretty informative. Here are some quick thoughts on the whole event:

Oculus Go and Santa Cruz

Oculus announced two new self contained headsets: the Go, a 3DoF inexpensive ($199) headset that will be coming early next year and much later, Project Santa Cruz, the 6DoF headset with inside-out tracking. Whats interesting is that both these devices will run mobile CPU/GPUs which means that 3 of the 4 VR headsets released by Oculus will have mobile processing power. If you are a VR developer, you better be optimizing your code to run on low horsepower devices, not beefy gaming machines.

Both Go and Santa Cruz are running a fork of Android

The move to inexpensive hardware makes sense, since Oculus has declared it their goal to bring 1 billion people into VR (no time frame was given 😉 )

Oculus Dash and new Home Experience

The older Oculus Home experience is also going away in favor of the new Dash dashboard that you’ll be able to bring up within any application. Additionally you’ll be able to pin certain screens from Dash enabled applications (which based on John Carmack‘s talk seem to be just Android apks). There could be an interesting rise of apps dedicated to this experience, kinda like Dashboard widgets for Mac when that was a thing.

Image result for Oculus Dash — Oculus Dash

The removal of the app-launcher from Oculus Home means Home now becomes a personal space that you can modify with props and environments to your liking. It looks beautiful, though not very useful. Hopefully it lasts longer than PlayStation’s Home

Image result for new Oculus Home Connect 4 — **New Oculus Home (pic from TechCrunch,com)**

New Avatars

The Oculus Avatars have also undergone a change. They no longer have the weird mono-color/ wax-dolls look but actually look more human with full color. This was also done to allow for custom props and costumes that you’ll be able to dress your avatar in in the future (go Capitalism 😉 )

Image result for new Oculus avatars — New Avatars (Pic from VentureBeat.com)

Another change is that the new Avatars have eyes with pupils! The previous ones with pupil-less eyes creeped me out. The eyes have also been coded to follow things happening in the scene to make them feel more real.

Oh and finally, the Avatar SDK is going to go cross platform, which means if you use the Avatars in your app, you’ll be able to use them in other VR platforms as well like Vive and DayDream.

Venues

One of the interesting things announced at Connect was Venues: a social experience for events like concerts, sports etc. It will be interesting to see how that goes.

There were numerous other talks that were interesting, from Lessons from One Year of Facebook Social to analyzing what is working in the app store. All the videos are on their YouTube Channel

Conclusion:

While I was wowed by a lot of the technology presented, it definitely feels like VR has a Crossing the Chasm problem: They have a pretty passionate alpha-user base but are trying really hard to actually get the larger non-gaming-centric audience in.

Image result for Crossing the Chasm

Oculus Go seems like a good idea to get the hardware and experience more widely distributed but what is really needed is that killer app that you really have to try in VR. The technology pieces are right there for the entrepreneur with the right idea.

Tips and Thoughts on Mobile WebVR Development

I have been involved in a few VR projects this last year. While the earlier prototypes used Unity as the development environment, some of the new ones use WebVR, an emerging web standard for VR development.

WebVR, as opposed to native-app VR, does have a few advantages:

JavaScript tooling is pretty good and getting better
Automatically falls back to an in-browser 3D experience on non-VR devices
Not having to compile the app to quickly check the changes in a browser is pretty awesome

The biggest thing though is that the kind of experiences we have always thought about: moving from one VR experience, is not possible in a series of native apps. I have heard the future of VR referred to as a “web of connected VR experiences” and that is the vision that is truly exciting.

Cyberspace as imagined by Ghost in the Shell

That said, current tooling is much better for VR native apps with most tools focusing on Unity, which is really the de-facto tool for game developers. However I really hope the tooling on WebVR side starts getting better.

Developing for WebVR

The way we currently build for WebVR is by using AFrame, a VR framework built on top of WebGL primarily maintained by Mozilla and the WebVR community. AFrame is built on top of ThreeJS, the most popular 3D library for WebGL. For desktop VR development, the only desktop browser that you don’t have to finagle with too much is Firefox. Most of the development is done on Oculus Rifts connected to some beefy PCs.

Another tool worth noting is Glitch which provides instant development setups for JavaScript based apps. Glitch has been very useful to quickly try out an idea and share it internally. The develop -> preview flow is pretty straight forward.

The developer workflow for mobile VR development though is a different story. While our current prototype had no requirements to be mobile, I recently tried it on a Google’s Daydream and found a few bugs. Fixing those seemed trivial, but actually doing that was a lot more painful than I would have thought. Here are some problems I ran into:

Cannot start a WebVR experience from inside VR

Currently there is no available web browser that can launch from the DayDream VR home menu. While Chrome on Android supports WebVR and will trigger a “Insert into Headset” DayDream action when a user taps on a VR button on a WebVR experience, there is no way to get to that experience from within DayDream itself. You cannot pin a WebVR experience to your DayDream Home and WebVR experiences don’t appear in your recent VR apps section.

This is actually really frustrating. The workflow to debug a DayDream error is:

Fix(?) bug
On phone, go to Chrome, launch app
Tap “VR” mode
Insert phone into headset
Verify Chrome Remote Debugger is still connected
See if the bug still appears
Pop phone out of headset

The constant popping of the phone in and out of the headset get old really fast. One option may be to add a “reload” button in your WebVR experience but I am not sure if that will work, since you aren’t supposed to be able to enter VR mode without an explicit user action (like a button tap)

One thought I did have was to create an Android app with the Manifest declaring it as a DayDream app, and then have its main view just be a WebView. Unfortunately that didn’t work, though I did get the app in the DayDream Home view. A different idea was to let this app launch Chrome with my WebVR app’s URL. Again, there were challenges: For one Chrome launched in conventional view and did not automatically trigger the VR split view for the left and right lenses. To add to this hack, I added a trigger to call AFrame’s enterVR() method when the page loaded which kinda worked but every launch caused this weird blink when the app went from 2D to VR mode that it was actually painful to use.

One HUGE tip in this workflow: Make sure you have enabled the DayDream debug menu selected the “Skip VR Entry Screens” without which the workflow mentioned adds like 2 more steps per debug.

Using Chrome Remote Debug

For a lot of my testing, all I needed was the console.log function from developer tools. You can see your logs using Chrome Developer Tools’ Remote Debug feature. Not sure I was doing it wrong but I kept losing connection to the active tab every time I reloaded the page to check. Really annoying. At the end of the day, I did discover the A-Frame Log Component, which I haven’t used yet, but intend to very soon.

Lack of a DayDream Controller Emulator

If you are developing for VR, your productivity is directly proportional to how much of the development you can do without putting on the headset. With WebVR, since your app automatically works in a browser, you can do a lot of development without the headset. Unfortunately this breaks down when you are trying to code around user interactions. You can use the Mouse as a raycast source which gets you partly there but you really want an emulator for the hand controllers to try different things out.

DayDream officially has an emulator for its controller, but that controller only seems to target Unity and Unreal based projects. There are other projects like DayFrame for AFrame but since my problem was specific to the DayDream controller, using a proxy emulator didn’t make much sense.

What I really wanted to do was to pair the official Google DayDream controller to my PC but I haven’t been able to find any way to do that yet.

Conclusion

I have been generally enjoying working with AFrame and it has a surprisingly (to me) strong community of active developers. However the developer workflows, esp for on-device testing, still need work. Ideally what I am looking for is a one click that deploys my WebVR app to a server and then launches DayDream pointed to the WebVR page running in fullscreen VR. Or even better, a WebVR/AFrame equivalent of Create React App or similar boilerplate projects, that automatically sets up all the best tools for developing and testing WebVR projects on both the browser and on-device.

Gotchas with JavaScript Promises and Fetch

This year has definitely been one of “return to JavaScript” for me (among other things) and its really interesting to see how far it has come. Between Cloud Functions, complex client applications using React, native app development with React Native and now even using AFrame/ThreeJS for WebVR development, I have been writing a LOT of JavaScript across the stack.

JavaScript’s increased responsibilities have unfortunately brought with it a corresponding increase in complexity which trips up many a returning developer (Gina Trapani’s excellent post is a good read if you are one of them..er..us). This month I have spent quite a few hours dealing with JavaScript’s Fetch API and the whole Promises API. There are a couple of gotchas there that I ran into that are worth sharing. Maybe they can save you a couple of hours down the road

Fetch and Promises start executing immediately. You cannot create a Promise object and store it to be executed later. If you are trying to avoid that, one option is to create a function that returns the Promise when needed.
Fetch requests have no concept of a timeout. If you need a Fetch request to be aborted after a certain number of seconds, the best way I have seen is to use Promise.race along with a different function that then throws the error to reject the Promise chain.
Making multiple calls with Fetch? Promise.all is a great option except that all requests / Promises start executing in parallel. If you need to execute them in sequence (like I did), you are out of luck without writing some utility code or leveraging a library. I ended up using this npm module.
Server error responses to Fetch calls are still interpreted as successes and call the success callback handler. Which means that you have to check for errors in your onSuccess which feels just wrong.

These are definitely some … debatable calls made by the guys deciding the api. If there are other gotchas you have run into, please share them here as well.

Slides from my “State of Blockchain Tech” talk

I recently gave a talk to the Comcast T&P Engineering group on the current state of Blockchain technology and where its going. The deck from the talk is shared below

Different Programming Metaphors

Its interesting that for an industry pushing humanity into the future, Software engineering practices have not changed significantly in the last 50 years. We are still using basic text editors with syntax highlighting, often on machines with hundreds of times the power of the devices they were originally designed for, an irony highlighted by Bret Victor in his talk linked below

I have been thinking about this for a while and collecting links on different ideas around this for the last few years. The deck below collects some of these ideas. If you have others that could be added, please leave a comment.

React Native Slides from my Modev DC talk

I was recently invited to give a talk at a Modev DC event held at the Capital One building. The slides are embedded below.

They are mostly based on my previous blog post on using React Native in an existing Android application which you can read here.

Thanks Modev, Luis and the Capital One team for having me over

Thoughts on Google IO 2017

Screen Shot 2017-05-20 at 3.43.40 PM.png

I spent this entire week in the west coast attending North America GDG Managers’ Summit and the I/O events. I am still processing some of the conversations from the Managers’ summit and how to use them to improve GDG Philadelphia that I help run so I’ll leave that to a future blog post so this post is restricted to the I/O event only.

The list of announcements both big and small are a mile long and have been well covered by other publications. My own gist of the announcements is here (feel free to send me a pull request if you wanna add anything there). Here are some thoughts on just I/O this year:

AI All the Things

Google’s internal things to pepper their products with features only possible using AI is clearly bearing fruit. From just pure utility features like enhanced copy and paste on Android to flagship features like Google Lens that allows object recognition in photos and videos on Google Photo and Assistant. I am particularly excited by the TensorflowLite project and programming for AI is something I am going to learn this year.

Immersive Computing (VR / AR / MR / xR)

People seem to love coming up with new terminology in this space. Google buckets the VR/AR technologies into “Immersive Computing”. They are doing some really interesting things in this space and I am glad to see them continue to push the state of art here. I was particularly impressed by Project Seurat that uses algorithms to allow developers to use simpler geometry to mimic complex, even movie quality, 3D models.

On the Tango / Augmented Reality side, Google Visual Positioning System truly impresses as well. In fact in one conversation, a Googler mentioned that the Google Maps team was heavily involved in the VPS development.

Visualization of a how a VPS (visual positioning service) map gets generated. This map of a Lowe's store has 10M+ feature points in it. pic.twitter.com/QMEkBIOtXY

— Clay Bavor (@claybavor) May 19, 2017

There were also some great demos of AR capture and reconstruction using the upcoming Asus Zenphone AR. Big question is when does a Google Pixel get a depth sensor and Tango support?

Actions on Google

Google’s new Actions platform that lets you build skills for Google Assistant on the Home, Android and iPhone was very interesting. The tooling basically consists of 3 components:

Actions on Google console that lets you manage your …um..actions
The API.ai tier that your actions probably need to manage natural language input
Chatbase, Google’s analytics platform for Chatbots that lets you observe your bots’ growth and engagement over time

I liked the system and it seems pretty trivial to make a simple Chatbot…I mean Action. They also announced a competition for the platform so get ready to see a lot of new ways you can order pizzas 😉

Android Dev

Android SDK + Firebase

Google continues to push Firebase as an essential part of Android development. Google cloud services have been catching up to AWS’ for a while and Firebase seems to be a great option to AWS Mobile. AWS’ tools are not friendly to a mobile developer and the Firebase tools do seem much more approachable. The addition of services like Performance Monitoring makes Firebase even more essential a part of the Android developers’ toolkit.

Google Play Developer Console Updates

I haven’t pushed anything to the Google Play Store since Picscribe in 2013. The publisher tools back then were functional and did a decent job I thought, but the latest updates to the publisher experience are fantastic. More tools to run A/B tests, greater visibility on top reasons for crashes, pre-release testing etc will allow developers to really optimize their apps just from the store.

Kotlin is an official second language for Android development

I am mostly ambivalent about Kotlin (😱). I had no particular issues with using Java for Android development, except maybe an occasional gripe about not being able to pass functions around. I am happy for Kotlin’s less verbose syntax but dread what happened with Swift’s introduction to the iOS ecosystem where the focus seemed to change from cool apps to various academic discussions (if I hear about monads one more time…).

Also the rapid evolution of the language meant that code examples and Stack Overflow answers stopped working in a few months. Lets hope this is less of an issue on the Android side.

And of course a new developer moving to Android now needs to know not only Java but Kotlin as well since the codebase will be a mix of the two.

On the flip side, the copy Java and paste as Kotlin feature in Android Studio is pretty dope

Cloud Functions: The rise of Lambdas

With so much functionality exposed as services from either Google or Amazon, developers can really power their apps with very little backend code development. That said, this leads to the rise in the need for some kind of glue layer that connects all these components together. Firebase’ Cloud Functions and Amazon’s Lambdas serve this need. The workflow for Amazon Lambdas is still slightly awkward, but Firebase’s workflow feels a lot better.

Final thoughts

There were a lot for cool technologies for show at I/O and it was awesome. The other amazing part was just meeting old friends from across the world and even making some new ones.

Philly GDG reunion! @androidphilly #io17 pic.twitter.com/DJCTXYZXmV

— Corey Latislaw #io17 (@corey_latislaw) May 19, 2017

I will also say this: This was one of the BEST organized events I have ever attended and kudos to Google for pulling it off. The session reservation system worked well, there was ample shade, food and drink and even they even got the weather to be nice for 3 days 😉

Till next year!

I won one of Phildelphia Business Journal’s 10 “Tech Disruptors for 2017” awards

They say don’t bury the lede but I just gave it away in the title ;). Phildelphia Business Journal comes up with a list of 10 Tech Disruptors every year who are “blazing new trails and inspiring others in the technology community”. I am one of the 10 for this year, and in extremely smart company of local CEOs, CTOs and Founders.

phl

Thanks for the honor @PHLBizJournal. Its great to see your name in the paper (well for the right reasons 😉 )

The return of the QR code

Over the last few years I have found myself defending QR codes in different conversations. While huge in the rest of the world, QR codes were never embraced in the west. Aesthetics was one that I had heard multiple times (“They are so ugly”) but they solved a real problem: bridging the offline world with the online one.

For whatever reason, neither Apple nor Google devices ship with a default QR code reader. ~~Apple’s default camera app has some image recognition built in which lets you scan iTunes gift cards, but neither Apple nor~~ (more surprisingly) Google showed any interest in QR codes. (Update: Apple added QR support for the default camera app in iOS 11)

But QR codes have snuck up in our society in the last few years. Some of these aren’t normal QR codes and maybe deserve their own label (scan codes?) but the idea remains the same: a graphic that codifies text that a scanner (camera) can read from a distance.

Snapchat popularized the idea with their Snapcodes that let users add other Snapchat users as friends.
Twitter, Kik, Facebook Messenger and Google Allo followed and now scanning a code to initiate a connection is starting to become normal.

Apps like the desktop experience for WhatsApp and the rumored upcoming desktop experience for Google Allo use QR codes to authorize their desktop accounts with the mobile ones
Airline and train tickets are using QR codes for their mobile boarding passes.
Windows’ error reporting

Screen Shot 2017-05-13 at 11.50.37 AM

Today, at F8, Facebook’s big developer event, they announced that Messenger will now support their scan-code, what they call Parametric Codes, which you’ll be able to use to do all sorts of things from friending to payments (offline payments via scan-codes is a big deal in China, where Messenger is taking a lot of its feature development cues from).

As happy as I am to see the return of these codes, the proprietary nature of each of them is a little bit of a bummer, but hopefully they will make the idea of scanning a code to connect with the real world more mainstream.

Update:

YCombinator Blog has a very interesting article on the rise of WeChat, but this section on QR codes is especially interesting

WeChat’s elevation of the QR code as a link from the offline became the lynchpin for China’s online-to-offline boom in 2015. Previously, to engage with a service or brand, a user would have to search or enter a website address. WeChat’s Pony Ma says of QR codes, “it is a label of abundant online information attached to the offline world”. This logic explains why WeChat chose to promote QR codes in the first place. QR codes never took off in the U.S. for three key reasons: (1) the #1 phone and the #1 social app didn’t allow you to scan QR codes. (2) Because of this, people had to download dedicated scanner apps, and then the QR code would take them to a mobile website, which is arguably more cumbersome than simply typing in the URL or searching for the brand on social media. (3) Early use cases focused on low-value, marketing related content and at times was merely spam. So, even though QR codes would’ve been U.S. marketers’ dream, it was a few steps too far to be useful.

With the established adoption of QR codes, WeChat launched “Mini Programs” as an extension of WeChat Official Accounts designed to enable users to access services in a more frictionless way just like the web browser did