Is your app really connected?

Presentation about connectivity in the Android applications shown during DroidCon Poland in Kraków on 01.12.2017.

Transcript

1. Is your app really connected? Piotr Wittchen wittchen.io github.com/pwittchen
3. Does your app call any web API? Sure. Almost every mobile app does.
4. What happens when the user wants to download some data? Scenario #1 1. User opens the app 2. Device is connected to the network 3. App downloads data from server 4. User can read data Senario #2 1. User opens the app 2. Device is not connected to the network 3. App tries to download data from server 4. ... 5. Connection timeout 6. Nothing happens or app crashes 7. User is not happy :-( Happy path :-D Unhappy path ;-(
5. What can we do about it? Source: https://developer.android.com/training/basics/network-ops/managing.html Is that enough?
6. Of course not It would be too easy. Don’t you think so? :-)
7. Let’s see another use case 1. User opens an app 2. Device is disconnected from the network 3. Connectivity check fails 4. Device gets connected to the network 5. User cannot access the network with the app 6. User is unhappy :-( Unhappy path ;-( How to fix this situation?
8. Let’s use the BroadcastReceiver! Now, we can react on the connectivity changes in real time
9. Lollipop arrives! We got a new shiny Android version! Hooray! But wait… Network Monitoring API has changed.
10. Lollipop arrives! We got a new shiny Android version! Hooray! But wait… Network Monitoring API has changed.
11. Marshmallow arrives! We got a new shiny Android version! Hooray! But wait… There’s a Doze Mode. We need yet another BroadcastReceiver notifying app that network is down when the phone sleeps.
12. Handling different connection types https://developer.android.com/training/basics/network-ops/managing.html
13. Handling different connection types https://developer.android.com/training/basics/network-ops/managing.html
14. Handling different connection types https://developer.android.com/training/basics/network-ops/managing.html
15. WiFi network can be disconnected from the Internet
16. Handling Internet connectivity Executed in a separate non-UI thread
17. China banned the Google! China is behind the Walled Garden We need to ping other host than Google or verify HTTP Status 204 (No Content)
18. Checking Internet connectivity in the Walled Garden Executed in a separate non-UI thread
20. ClearText Traffic Starting with Android 9.0 (API level 28), cleartext support is disabled by default. We need to apply additional network security configuration in such cases. • https://developer.android.com/training/articles/security-config#CleartextTrafficPermitted • https://stackoverflow.com/questions/45940861/android-8-cleartext-http-traffic-not-permitted/50834 600#50834600
21. How often should we check Internet connectivity? It depends on our use case Continuous checking in a given interval is more reliable, but consumes more data transfer and drains the battery Sometimes one time check is enough
22. Mixing it all together Network BroadcastReceiver for pre-Lollipop devices Managing different connection types Network Callback from Lollipop Checking Internet connectivity for Walled Garden Doze mode Checking Internet connectivity with Socket Frequency of checking Internet connectivity Handling connectivity check asynchronously ClearText traffic
24. So what should I do now? You can implement all of that stuff by yourself or...
25. You can use ReactiveNetwork library! It will do all the work for you
26. Why would I use it? • ~3 years of development and maintenance • 10 developers contributed to the code-base • 41 releases so far • More than 80% of code covered by unit tests • Documentation, JavaDocs and exemplary apps • Works with RxJava1.x and RxJava2.x (on separate artifacts and git branches) • Up to date with the latest RxJava version (which is used as a dependency) • Works with Java and Kotlin • It’s free and open-source: https://github.com/pwittchen/ReactiveNetwork • Backed by Travis Continuous Integration Server • Verified by static code analysis tools (CheckStyle, PMD, FindBugs, Lint, NullAway) • Tested in production • Available on the Maven Central Repository (easy to use with Gradle)
27. ReactiveNetwork does not force you to use any concrete solution or strategy Pick whatever you need from it or extend it
28. The simplest example
29. The simplest example
30. The simplest example
31. The simplest example
32. Filtering connection types
33. Filtering connection types
34. Filtering connection types
35. Network observing strategies is implemented by: Correct strategy is chosen by the library automatically, but we can use any strategy explicitly if we want to.
36. Internet observing strategies is implemented by:
37. Observing Internet Connectivity (periodically)
38. Observing Internet Connectivity (periodically)
39. Observing Internet Connectivity (periodically)
40. Observing Internet Connectivity (periodically)
41. Checking Internet Connectivity (only once)
42. Checking Internet Connectivity (only once)
43. Customization of the Internet connectivity check We can use and type from RxJava2 depending on our use case We can customize: • host • port • timeout in ms • initial observing interval in ms • ping interval in ms • strategy https://github.com/pwittchen/ReactiveNetwork#observing-internet-connectivity
44. Chaining stream of network and Internet connectivity
45. Chaining stream of network and Internet connectivity
46. Chaining stream of network and Internet connectivity
47. Chaining stream of network and Internet connectivity
48. Chaining stream of network and Internet connectivity
49. Chaining stream of network and Internet connectivity
50. Chaining stream of network and Internet connectivity
51. Chaining stream of network and Internet connectivity
52. Integration with OkHttp
53. Integration with OkHttp
54. Integration with OkHttp
55. Integration with OkHttp
56. Integration with OkHttp
57. Integration with OkHttp
58. Integration with OkHttp
59. Integration with OkHttp
60. Integration with OkHttp
61. Integration with OkHttp
62. Integration with OkHttp
63. Integration with OkHttp
64. Integration with Retrofit
65. Integration with Retrofit
66. Integration with Retrofit
67. Integration with Retrofit
68. Integration with Retrofit
69. Integration with Retrofit
70. Integration with Retrofit
71. Integration with Retrofit
72. Integration with Retrofit
73. Respecting battery state How to perform a data synchronization, while being connected to AC and WiFi network at the same time?
74. https://github.com/pwittchen/RxBattery
75. Respecting battery state
76. Respecting battery state
77. Respecting battery state
78. Respecting battery state
79. Respecting battery state
80. Respecting battery state
81. Respecting battery state
82. Respecting battery state
83. Respecting battery state
84. Integration with any code based on RxJava is possible
85. ReactiveNetwork follows the official Google recommendations https://developer.android.com/develop/quality-guidelines/building-for-billions-connectivity.html https://developer.android.com/develop/quality-guidelines/building-for-billions-data-cost.html https://developer.android.com/training/basics/network-ops/managing.html Make your app usable offline Use less bandwidth on slower connections Detect network changes, then change app behavior
86. https://github.com/pwittchen/ReactiveNetwork/#who-is-using-this-library Is anyone using this library now? and others 5M+ downloads 10M+ downloads 50k+ downloads 1k+ downloads 500k+ downloads
87. Is anyone using this library now?
88. Is anyone using this library now?
89. Is anyone using this library now?
90. Contributions are welcome! https://github.com/pwittchen/ReactiveNetwork
91. Summary • We need to be aware of network and Internet connectivity • Apps can work off-line • Apps can be disconnected from the network anytime • WiFi network can be disconnected from the Internet anytime • Battery of the device should not be drained • Mobile data transfer should be used carefully • We should provide the best User Experience possible • Do not reinvent the wheel - we have libraries :-)
92. Is your app really connected? Piotr Wittchen wittchen.io github.com/pwittchen Thank you for the attention! Questions?