How to setup your Android app to use Protobuf with Kotlin flavor and ignoring Protobuf pros and cons!

1. @mohsenoid
Using in an Android app
+ extra Kotlin flavor

2. @mohsenoid
2014 FIFA World Cup Brazil
A Short Story

3. @mohsenoid

4. @mohsenoid
In a single Text Message: 160 Char
W14(3)|Type*(1)|#ofGoals(128)|UserPoint(4)|Qualified(16)|Error**(1)|Checksum(1)
*Type: RESULT("R") / PREDICT("P") / STATES("S")
** Error: User last predict message error call back

5. @mohsenoid
The Automotive
Assistant
Germanautolabs.com
HelloChris.ai

6. @mohsenoid
* MTU: Maximum Transmission Unit
* Package/Sec: 7.5~1.25 milliseconds
https://punchthrough.com/blog/posts/maximizing-ble-throughput-on-ios-and-android
BLE Data Throughput
Best case MTU Worst case MTU
512 Bytes 20 Bytes!!!

7. @mohsenoid
Google developed Protocol Buffers for internal usage and
also provided a code generator for multiple languages.
https://github.com/google/protobuf
C++ / Java / Python / Objective-C / C# / JavaNano / JavaScript / Ruby / Go / PHP / Dart

8. @mohsenoid
● Protocol Buffers is a method of serializing structured data
● Useful in developing programs to communicate with each
other and also good for storing data
● interface description language: describes the structure of
some data
● a program that generates source code from description
for generating or parsing a stream of bytes that
represents the structured data
What is Protocol Buffers?

9. @mohsenoid
Setting up the Application project

10. @mohsenoid
top-level build.gradle
buildscript {
ext.protobufVersion = '0.8.3'
...
dependencies {
...
classpath "com.google.protobuf:protobuf-gradle-plugin:$protobufVersion"
}
...

11. @mohsenoid
creating a Java module

12. @mohsenoid
Java module build.gradle
apply plugin: 'com.google.protobuf'
…
// lite version is recommended for Android apps
implementation 'com.google.protobuf:protobuf-lite:3.0.0'
...

13. @mohsenoid
Protobuf plugin settings
protobuf {
protoc { // setting proto compiler
artifact = 'com.google.protobuf:protoc:3.0.0'
}
plugins { // ask proto plugin to use java lite code generator
javalite {
artifact = 'com.google.protobuf:protoc-gen-javalite:3.0.0'
}
}

14. @mohsenoid
Protobuf plugin settings
generateProtoTasks {
all().each { task ->
task.builtins {
remove java // because of using javalite we should remove java outputs
}
task.plugins {
javalite {} // and use javalite
}
}

15. @mohsenoid
Protobuf plugin output
sourceSets {
main.java.srcDirs += "${protobuf.generatedFilesBaseDir}/main/javalite"
}

16. @mohsenoid
Default proto dir
src/main/proto

17. @mohsenoid
a sample proto file
syntax = "proto2";
package tutorial;
option java_package = "com.mohsenoid.tutorial";
option java_outer_classname = "AddressBookProtos";

18. @mohsenoid
message Person {
required string name = 1;
required int32 id = 2;
optional string email = 3;
message PhoneNumber {
required string number = 1;
optional PhoneType type = 2 [default = HOME];
}
repeated PhoneNumber phones = 4;

19. @mohsenoid
enum PhoneType {
MOBILE = 0;
HOME = 1;
WORK = 2;
}
}
message AddressBook {
repeated Person people = 1;
}

20. @mohsenoid

21. @mohsenoid
Kotlin reported issue

22. @mohsenoid
Kotlin reported issue #100:
https://github.com/google/protobuf-gradle-plugin/issues/100
compileKotlin {
dependsOn('generateProto')
}
compileTestKotlin {
dependsOn('generateProto')
}

23. @mohsenoid
Let’s finish it!

24. @mohsenoid
Protocol buffer is a useful way of
serializing and deserializing data
(also obfuscating!!!)
perfectly optimized in case of data transmission size and also avoiding all manual data typing

25. @mohsenoid
@mohsenoid
Google Project: https://developers.google.com/protocol-buffers
Definition: https://developers.google.com/protocol-buffers/docs/proto3
Sample Repo: https://github.com/mohsenoid/protobuf_android_sample
Article: https://proandroiddev.com/96132340de5c