Rxify - a simple spell for complex RxJava operators

Droidcon Boston 2017
This talk is about the operators which upon reading the document look daunting at first but if you get a grasp of them, they can be quite useful in almost all the apps you code. RxJava is your friend, it will make your life easier. With RxJava many complex tasks can be accomplished easily and without errors. As the title says, `Rxify` - you just need to cast the spells and all your work will be done. From hitting the cache-first to performing retries, just cast the spells and you are good to go. https://medium.com/@ragdroid/rxify-a-simple-spell-for-complex-rxjava-operators-part-1-4c31921583c4#.6hxqs39e6

Transcript

1. #DroidConBos @ragdroid `Rxify` Presented By : Garima Jain @ragdroid A simple spell for complex RxJava operators
2. Who?
3. #DroidConBos @ragdroid `Rxify` is for? • Already working on RxJava - More to learn.
4. #DroidConBos @ragdroid `Rxify` is for? • Already working on RxJava - More to learn. • Beginner - Time to start Rxifying your apps
5. #DroidConBos @ragdroid `Rxify` is for? • Already working on RxJava - More to learn. • Beginner - Time to start Rxifying your apps • Pros - Talk will be fun!
6. #DroidConBos @ragdroid `Rxify` is for? • Already working on RxJava - More to learn. • Beginner - Time to start Rxifying your apps • Pros - Talk will be fun! • Not Interested?
7. #DroidConBos @ragdroid `Rxify` is for?
8. What?
9. #DroidConBos @ragdroid • `Rxify` - term signifies use of RxJava • RxJava makes our lives simpler. • Cast a spell (use an operator) and we are good to go. `Rxify`
10. #DroidConBos @ragdroid • Reactive Extensions for JVM (Java Virtual Machine). • Observer pattern for sequences of data / events. RxJava
11. #DroidConBos @ragdroid RxJava makes lives simpler • Never having to worry about : • Low-level Threading • Synchronisation • Background Processing
12. Why?
13. #DroidConBos @ragdroid RxJava operators at first glance
14. #DroidConBos @ragdroid RxJava operators at first glance
15. #DroidConBos @ragdroid RxJava operators at first glance • Complex • Hard to understand • Marble Diagrams? What!!
16. “The Plan”
17. The Plan • Basics • Spells • Complex Spells • Thread Travel
18. The Plan • Basics • Spells ✦ map() ✦ flatmap() ✦ filter() • Complex Spells • Thread Travel
19. The Plan • Basics • Spells • Complex Spells ✦ zip() ✦ concat() vs merge() ✦ buffer() ✦ debounce() ✦ flatmap() vs concatMap() vs switchMap() • Thread Travel
20. The Plan • Basics • Spells • Complex Spells • Thread Travel ✦ subscribeOn() ✦ observeOn()
21. Basics
22. #DroidConBos @ragdroid • Observable produces items, • Subscriber consumes those items. • Observable calls : (Actions) • onNext() multiple times • followed by onComplete() • OR onError() Basics
23. #DroidConBos @ragdroid • Operators : • manipulate items between producer and consumer. • Schedulers • Main Thread • Computation, IO (Background Thread) • Test Scheduler Basics
24. #DroidConBos @ragdroid Observable Pattern Producer Consumer A B C items Observable emits Subscriber consumes
25. #DroidConBos @ragdroid Just-ify Simple Observable String Hello World! Observable.just("Hello World!”); Observable <String> time Hello World
26. #DroidConBos @ragdroid A B C A B C Rx-ify String Array Simple Observable List<String> source = Arrays.asList("A", "B", "C");
 Observable.fromIterable(source); Observable <String>
27. “Spells” operators
28. “Map-io” map() operator
29. #DroidConBos @ragdroid Map Transforms every element of a collection of items.
30. #DroidConBos @ragdroid Map-io Observable <Integer> Map Observable <Integer> 1 2 3 10 20 30
31. #DroidConBos @ragdroid Observable <Integer> Map Observable.fromIterable(Arrays.asList(1, 2, 3))
 .map(integer -> integer * 10); Observable <Integer> 1 2 3 10 20 30
32. “FlatMap-um” flatMap() operator
33. #DroidConBos @ragdroid FlatMap • Every element of a collection • To another collection of items • Combines them into a single collection.
34. #DroidConBos @ragdroid FlatMap-um Observable <String> FlatMap Observable <String> Hello World How Are You? Hello World How Are You?
35. #DroidConBos @ragdroid Observable <String> FlatMap List<String> source = Arrays.asList("Hello World", "How Are You");
 Observable.fromIterable(source)
 .flatMap(s -> Observable.fromIterable(
 Arrays.asList(s.split(" ")))); Observable <String> Hello World How Are You? Hello World How Are You?
36. “Filter-rum” filter() operator
37. #DroidConBos @ragdroid Filter Filter the original collection to emit items that satisfy a condition.
38. #DroidConBos @ragdroid Filter-rum Observable <Integer> Filter Observable <Integer> 1 2 3 1 4 5 6 3 5 7 7
39. #DroidConBos @ragdroid Observable <Integer> Filter Observable <Integer> 1 2 3 1 4 5 6 3 5 getSourceObservable() .filter(integer -> integer % 2 == 1) 7 7
40. “Comples spells” complex operators
41. “Zip-pyosa” zip() operator
42. #DroidConBos @ragdroid Zip • Combine multiple collections together • According to some function • Emit the result of each combination.
43. #DroidConBos @ragdroid Zip Marble Diagram
44. #DroidConBos @ragdroid Zip Marble Diagram Looks a little Overwhelming
45. #DroidConBos @ragdroid Zip Marble Diagram Looks a little Overwhelming
46. #DroidConBos @ragdroid Fictional Problem (Polyjuice Potion) • Hermione wants to prepare Polyjuice potion (P = R + H). * • She is waiting for task Ron (R) to bring FluxWeed. • She is waiting for task Harry (H) to bring hair. • Both tasks R and H are executing asynchronously. • Only after both R and H are completed then P can start. * ‘+’ is some complex function (brewing the Polyjuice in this case)
47. #DroidConBos @ragdroid Zip-Yosa Observable <FluxWeed> Zip Observable <Polyjuice> FluxWeed CrabHair Polyjuice Potion Observable <CrabHair>
48. #DroidConBos @ragdroid Observable <FluxWeed> Zip Observable <Polyjuice> FluxWeed CrabHair Polyjuice Potion Observable <CrabHair> 
 return Observable.zip( fluxWeedObservable, hairObservable,
 (fluxWeed, student) -> new PolyJuice(fluxWeed, student.getHair()) .prepare()) );
49. #DroidConBos @ragdroid Observable <FluxWeed> Zip Observable <Polyjuice> FluxWeed CrabHair Polyjuice Potion Observable <CrabHair> 
 return Observable.zip( fluxWeedObservable, hairObservable,
 (fluxWeed, student) -> new PolyJuice(fluxWeed, student.getHair()) .prepare()) );
50. #DroidConBos @ragdroid Observable <FluxWeed> Zip Observable <Polyjuice> FluxWeed CrabHair Polyjuice Potion Observable <CrabHair> 
 return Observable.zip( fluxWeedObservable, hairObservable,
 (fluxWeed, student) -> new PolyJuice(fluxWeed, student.getHair()) .prepare()) );
51. #DroidConBos @ragdroid Observable <FluxWeed> Zip Observable <Polyjuice> FluxWeed CrabHair Polyjuice Potion Observable <CrabHair> 
 return Observable.zip( fluxWeedObservable, hairObservable,
 (fluxWeed, student) -> new PolyJuice(fluxWeed, student.getHair()) .prepare()) );
52. #DroidConBos @ragdroid Can you relate the Polyjuice Potion Problem to any coding problem?
53. #DroidConBos @ragdroid Can you relate the Polyjuice Potion Problem to any coding problem? YES! When multiple API calls are executing simultaneously.
54. “Concat-ify” concat() operator “Merge-os” merge() operator VS
55. #DroidConBos @ragdroid Concat “Emit the emissions from two or more Observables without interleaving them” source “Combine multiple Observables into one by merging their emissions” source Merge
56. #DroidConBos @ragdroid Concat Merge 1 2 3 4 8 9 1 2 3 4 8 9 1 2 3 4 8 9 1 2 3 4 8 9 Concat-ify Merge-os
57. #DroidConBos @ragdroid Fictional Problem (Snape’s Assignment) • Professor Snape has requested all students to write an essay on werewolves. • The students who will turn in the essay first will get more points than the ones submitting later. • Students are divided into four house observables : • GryffindorObservable (G), • SlytherinObservable (S), • HufflepuffObservable (H) and • RavenclawObservable(R)).
58. #DroidConBos @ragdroid Observable <Gryffindor> Snape’s Assignment - Submission R1 R2 H1 H2 Observable <Ravenclaw> Observable <Hufflepuff> G1 G2 S1 S2 Observable <Slytherin>
59. #DroidConBos @ragdroid Observable<Student> concatify() {
 Observable<Student> slytherinObservable = getObservable(House.SLYTHERIN);
 Observable<Student> huffleObervable = getObservable(House.HUFFLEPUFF);
 Observable<Student> ravenObservable = getObservable(House.RAVENCLAW);
 Observable<Student> gryffindorObservable = getObservable(House.GRYFFINDOR);
 return Observable.concat(
 slytherinObservable,
 huffleObervable,
 ravenObservable,
 gryffindorObservable);
 } Snape’s Assignment - Draco’s trick
60. #DroidConBos @ragdroid Snape’s Assignment - Draco’s trick S1 S2 H1 H2 R1 R2 G1 G2 Concat-ify Observable <Gryffindor> R1 R2 H1 H2 Observable <Ravenclaw> Observable <Hufflepuff> G1 G2 S1 S2 Observable <Slytherin>
61. #DroidConBos @ragdroid Guess who is not so pleased?
62. #DroidConBos @ragdroid Guess who is not so pleased? YES!
63. #DroidConBos @ragdroid Guess who is not so pleased? YES! Poor Hermione
64. #DroidConBos @ragdroid Observable<Student> mergeos() {
 Observable<Student> slytherinObservable = getObservable(House.SLYTHERIN);
 Observable<Student> huffleObervable = getObservable(House.HUFFLEPUFF);
 Observable<Student> ravenObservable = getObservable(House.RAVENCLAW);
 Observable<Student> gryffindorObservable = getObservable(House.GRYFFINDOR);
 return Observable.merge(
 slytherinObservable,
 huffleObervable,
 ravenObservable,
 gryffindorObservable);
 } Snape’s Assignment - Hermione’s fix
65. #DroidConBos @ragdroid Snape’s Assignment - Hermione’s fix G1 S1 G2 R1 H1 S2 R2 H2 Merge-os Observable <Gryffindor> R1 R2 H1 H2 Observable <Ravenclaw> Observable <Hufflepuff> G1 G2 S1 S2 Observable <Slytherin>
66. #DroidConBos @ragdroid Snape’s Assignment - Hermione’s fix
67. #DroidConBos @ragdroid • Hit the cache first • If data found return data • Else Network call Problem : Cache First Then Network
68. #DroidConBos @ragdroid • Hit the cache first • If data found return data • Else Network call Problem : Cache First Then Network Concat-ify
69. #DroidConBos @ragdroid • Hit the cache first • If data found return data • Else Network call Observable<List<Lecture>> cacheObservable = getLecturesFromCache();
 Observable<List<Lecture>> lecturesFromServer = getLecturesFromServer();
 return cacheObservable .concatWith(lecturesFromServer)
 .take(1); Problem : Cache First Then Network
70. #DroidConBos @ragdroid Fictional Problem (The Battle) • Dumbledore’s army (Harry, Hermione, Ron and others) • Death Eaters (Lucius Malfoy, Bellatrix Lestrange and others) • Each team is casting lethal spells against the other team. • Dumbledore’s army is not as experienced as the Death Eaters. • Spells produced by Death Eaters is overwhelming the Dumbledore’s army (consumer).
71. “Buffer-undum” buffer() operator
72. #DroidConBos @ragdroid Buffer • Buffer small chunks of items • Instead of emitting one item at a time. • Emit chunks
73. #DroidConBos @ragdroid Buffer-undum Buffer Observable <Spell> 1 2 3 4 Observable <Spell> 1 2 3 4
74. #DroidConBos @ragdroid Observable <Spell> Buffer Observable <Spell> 1 2 3 4 1 2 getSpellsObservable()
 .buffer(2); //count 3 4
75. #DroidConBos @ragdroid Buffer-undum Buffer LOSS-LESS Observable <Spell> 1 2 3 4 Observable <Spell> 1 2 3 4
76. #DroidConBos @ragdroid Buffer Observable <Spell> 1 2 3 4 Observable <Spell> 1 2 3 4
77. “Debounce-y” debounce() operator
78. #DroidConBos @ragdroid Debounce Emit an item only when, some time has passed since it last emitted anything.
79. #DroidConBos @ragdroid Debounce-y Debounce Observable <Spell> 1 2 3 4 Observable <Spell> 1 2 4
80. #DroidConBos @ragdroid Observable <Spell> 1 2 3 4 Observable <Spell> 1 2 4 Debounce
81. #DroidConBos @ragdroid Observable <Spell> 1 2 3 4 Observable <Spell> 1 2 4 LOSSY Debounce
82. #DroidConBos @ragdroid Observable <Spell> 1 2 3 4 Observable <Spell> 1 2 4 PROBLEM SOLVED Debounce
83. #DroidConBos @ragdroid Observable <Spell> 1 2 3 4 Observable <Spell> 1 2 4 getSpellsObservable()
 .debounce(300, TimeUnit.MILLISECONDS); Debounce
84. #DroidConBos @ragdroid Problem : Optimize Network Traffic Track User Events using any analytics library.
85. #DroidConBos @ragdroid Problem : Optimize Network Traffic Track User Events using any analytics library. Simple Approach Server request whenever an event occurs. Over chatty producer (User Events) Slow Consumer (Network Request)
86. #DroidConBos @ragdroid Problem : Optimize Network Traffic Track User Events using any analytics library. Buffer-undum Buffer some events before making a network request. Buffer-undum
87. #DroidConBos @ragdroid Problem : Optimize Network Traffic Track User Events using any analytics library. Buffer-undum Observable.just(new ArrayList<Event>())
 .buffer(3) // buffer count
 .flatMap(events -> Observable.just(new TrackRequest(events)));
88. #DroidConBos @ragdroid Problem : Auto-Search AutoComplete Search Suggestions
89. #DroidConBos @ragdroid Problem : Auto-Search AutoComplete Search Suggestions Simple Approach Server request whenever a character is typed Over chatty producer (User Input) Slow Consumer (Network Request)
90. #DroidConBos @ragdroid AutoComplete Search Suggestions Debounce-y Make a network request only if user has stopped typing. Debounce-y Solution : Auto-Search
91. #DroidConBos @ragdroid Solution : Subject
92. #DroidConBos @ragdroid Solution : Subject Producer Consumer A B C items Observable emits Subscriber consumes
93. #DroidConBos @ragdroid Solution : Subject Producer Consumer A B C items Subject emits Subscriber consumes subject.onNext()
94. #DroidConBos @ragdroid Solution : Subject Producer Consumer A B C items Subject emits Subject consumes subject.onNext() subject.subscribe()
95. #DroidConBos @ragdroid Solution : Subject Subject<T> extends Observable<T> implements Observer<T> { }
96. #DroidConBos @ragdroid Solution : Subject Subject<T> extends Observable<T> implements Observer<T> { } AsyncSubject BehaviorSubject PublishSuject ReplaySubject
97. #DroidConBos @ragdroid Solution : Subject Subject<T> extends Observable<T> implements Observer<T> { } via-Hedwig We are going to use a PublishSubject for this purpose.
98. #DroidConBos @ragdroid Solution : Subject Subject<T> extends Observable<T> implements Observer<T> { } via-Hedwig PublishSubject : once you subscribe, you get all the subsequent items.
99. #DroidConBos @ragdroid AutoComplete Search Suggestions Debounce-y publishSubject
 .debounce(300, TimeUnit.MILLISECONDS)
 .flatMap(new Function<String, ObservableSource<List<Book>>>() {
 @Override
 public ObservableSource<List<Book>> apply(String searchTerm) {
 return dataSource.getBook(searchTerm);
 }
 }) Solution : Auto-Search
100. #DroidConBos @ragdroid Observable <String> B Book Solution : Auto-Search Debounce-y String B Book Boo Bo x x
101. #DroidConBos @ragdroid AutoComplete Search Suggestions Debounce-y Solution : Auto-Search publishSubject
 .debounce(300, TimeUnit.MILLISECONDS)
 .flatMap(new Function<String, ObservableSource<List<Book>>>() {
 @Override
 public ObservableSource<List<Book>> apply(String searchTerm) {
 return dataSource.getBook(searchTerm);
 }
 })
102. #DroidConBos @ragdroid Observable <List<Book>> flatMap-um Observable <String> B Solution : Auto-Search (FlatMap) List1 List2 Book
103. #DroidConBos @ragdroid Observable <List<Book>> Observable <String> B Solution : Auto-Search (FlatMap) List1 Nice & Good! List2 Book
104. #DroidConBos @ragdroid Observable <List<Book>> Observable <String> B Solution : Auto-Search (FlatMap) What if Response (“Book) arrived before Response(“B”)? Book
105. #DroidConBos @ragdroid Observable <List<Book>> List1 List2 flatMap-um Observable <String> B Book Solution : Auto-Search (FlatMap) 1000ms 200ms
106. #DroidConBos @ragdroid Solution : Auto-Search
107. #DroidConBos @ragdroid Solution : Auto-Search (FlatMap)
108. “ConcatMap-pum” concatMap() operator
109. #DroidConBos @ragdroid ConcatMap • Just like flatMap(), but … • Concatenates rather than merges
110. #DroidConBos @ragdroid Observable <List<Book>> List1 List2 flatMap-um Observable <String> B Book Solution : Auto-Search (FlatMap) 1000ms 200ms
111. #DroidConBos @ragdroid Observable <List<Book>> List1 concatMap-um Observable <String> B Book Solution : Auto-Search (ConcatMap) 1000ms 200ms
112. #DroidConBos @ragdroid Observable <List<Book>> List1 concatMap-um Observable <String> B Book Solution : Auto-Search (ConcatMap) 1000ms 200ms S U B S C R I B E
113. #DroidConBos @ragdroid Observable <List<Book>> List1 concatMap-um Observable <String> B Solution : Auto-Search (ConcatMap) 1000ms Book 200ms List2
114. #DroidConBos @ragdroid Solution : Auto-Search (ConcatMap)
115. #DroidConBos @ragdroid Solution : Auto-Search (ConcatMap) TOO SLOW!
116. “SwitchMap-pum” switchMap() operator
117. #DroidConBos @ragdroid SwitchMap • Just like flatMap(), but … • Unsubscribe to previous observable • When new item emitted
118. #DroidConBos @ragdroid SwitchMap Do not think of “SwitchMap” as switch() {case: }
119. #DroidConBos @ragdroid SwitchMap Think of it as switchTo(newObservable)
120. #DroidConBos @ragdroid SwitchMap It was earlier called flatMapLatest()
121. #DroidConBos @ragdroid Observable <List<Book>> List1 List2 flatMap-um Observable <String> B Book Solution : Auto-Search (FlatMap) 1000ms 200ms
122. #DroidConBos @ragdroid Observable <List<Book>> List1 List2 switchMap-um Observable <String> B Book Solution : Auto-Search (SwitchMap) 1000ms 200ms
123. #DroidConBos @ragdroid Observable <List<Book>> List2 switchMap-um Observable <String> B Book Solution : Auto-Search (SwitchMap) 200ms UNSUBSCRIBE
124. #DroidConBos @ragdroid Solution : Auto-Search (SwitchMap)
125. #DroidConBos @ragdroid Solution : Auto-Search (SwitchMap) ALL SET!
126. “Thread Travel” with RxJava
127. #DroidConBos @ragdroid Thread It’s a thread of execution in a program.
128. #DroidConBos @ragdroid Schedulers For introducing multi-threading.
129. #DroidConBos @ragdroid Schedulers • Schedulers.computation() - for computational work • Schedulers.io() - for IO-bound work • AndroidSchedulers.mainThread() - executes actions on Android main thread • new TestScheduler() - intended for testing purposes
130. #DroidConBos @ragdroid • A new Thread is like a parallel universe • We all live in the main thread • Switching a thread - opening a portal to another dimension Fictional Threading
131. #DroidConBos @ragdroid • Hermione is always eager to gain knowledge. • Two lectures are going on at the same time. • She is stuck in the dilemma of how to attend both the lectures. Fictional Problem (Hermione’s Time Turner)
132. #DroidConBos @ragdroid • Hermione is always eager to gain knowledge. • Two lectures are going on at the same time. • She is stuck in the dilemma of how to attend both the lectures. Fictional Problem (Hermione’s Time Turner) via-Hedwig Time Turner allows hermione travel back in time
133. “Expecto-SubscribeOn” subscribeOn() operator
134. #DroidConBos @ragdroid SubscribeOn “specify the Scheduler on which an Observable will operate”
135. #DroidConBos @ragdroid SubscribeOn • Specify the Starting Scheduler • Switch threads
136. #DroidConBos @ragdroid SubscribeOn Start the magic
137. “Observe-ate” observeOn() operator
138. #DroidConBos @ragdroid ObserveOn • True magic of thread travel • Switch threads
139. #DroidConBos @ragdroid ObserveOn • True magic of thread travel • Switch threads via-Hedwig Potterly speaking, observe-ate can open portals to different dimensions
140. #DroidConBos @ragdroid Main Dimension Hermione’s Time Turner : Solution Main Thread
141. #DroidConBos @ragdroid Expecto-subscribeOn Background Main Thread Hermione’s Time Turner : Solution
142. #DroidConBos @ragdroid Expecto-subscribeOn Task Started Background Thread Hermione’s Time Turner : Solution ⌛ Main Thread
143. #DroidConBos @ragdroid Expecto-subscribeOn observe-ate Task Started Task Completed Hermione’s Time Turner : Solution Main Thread Background Thread
144. #DroidConBos @ragdroid Expecto-subscribeOn observe-ate Task Started Task Completed Hermione’s Time Turner : Solution Main Thread Background Thread
145. #DroidConBos @ragdroid Hermione’s Time Turner : Solution Observable.defer(new Callable<ObservableSource<Lecture>>() {
 @Override
 public ObservableSource<Lecture> call() {
 return Observable.just(new Lecture(id)) .delay(id, TimeUnit.SECONDS);
 }
 }); getLectureObservable()
146. #DroidConBos @ragdroid Hermione’s Time Turner : Solution lectureOneObservable = getLectureObservable(1)
 .subscribeOn(AndroidSchedulers.mainThread())
 .observeOn(AndroidSchedulers.mainThread())
 .doOnNext(lecture -> {
 if (getView() != null) {
 getView().append("Attended Lecture " + lecture.getId());
 }
 });
147. #DroidConBos @ragdroid Hermione’s Time Turner : Solution lectureTwoObservable = getLectureObservable(2)
 .subscribeOn(Schedulers.io())
 .observeOn(AndroidSchedulers.mainThread())
 .doOnNext(lecture -> {
 if (getView() != null) {
 getView().append("Attended Lecture " + lecture.getId());
 }
 });
148. #DroidConBos @ragdroid Hermione’s Time Turner : Solution 
 Observable.zip(lectureOneObservable, lectureTwoObservable,
 (lecture, lecture2) -> String.format("Attended Lectures %s and %s", lecture.getId(), lecture2.getId()))
 .subscribe(message -> {
 if (getView() != null) {
 getView().append(message);
 }
 }); Zip the two
149. #DroidConBos @ragdroid Hermione’s Time Turner : Action
150. #DroidConBos @ragdroid • Learn by practice • Make RxJava your friend and not a foe • Learn by examples - Kaushik Gopal RxJava https://github.com/kaushikgopal/RxJava-Android-Samples • Have a look at the source code of demo app https://github.com/ragdroid/rxify • Slides at speakerdeck https://speakerdeck.com/ragdroid/rxify-a-simple-spell-for-complex-rxjava-operators-1 • My Medium blogs for more details https://medium.com/@ragdroid What’s Next
151. #DroidConBos @ragdroid Acknowledgements via-Hedwig - Android community - Vikas @vickyturtle - Julien - Fueled - Ritesh @_Riteshhh - Droidcon Boston team
152. #DroidConBos @ragdroid Acknowledgements via-Hedwig The terms lossy and lossless have been inspired from the post here.
153. #DroidConBos @ragdroid Acknowledgements via-Hedwig Technical Definitions have been taken from website. http://reactivex.io/documentation/operators.html
154. #DroidConBos @ragdroid Acknowledgements via-Hedwig Response on medium article from Paul Woitaschek : https://medium.com/@woitaschek/its-better-to-use-switchmap- as-you-don-t-care-about-old-results-315029110c75
155. #DroidConBos @ragdroid Acknowledgements via-Hedwig Gifs have been taken from giphy.com.
156. #DroidConBos @ragdroid Thank You
157. FUELED http://fueled.com hello@fueled.com +1.800.962.4587 568 Broadway, 11th Flr. New York, NY 10012 Questions?