⏰ Dagger Track

A gradle plugin that automatically adds clock tracking for your components and subcomponents.

For example, for HomeFragment calling inject method you will see following output in your logcat at runtime:

D/DaggerTrack: Total time of me.amanjeet.daggertrack.ui.HomeFragment: 10420ms
D/DaggerTrack: Total On CPU time of me.amanjeet.daggertrack.ui.HomeFragment: 4230ms
D/DaggerTrack: Total Off CPU time of me.amanjeet.daggertrack.ui.HomeFragment: 6190ms

Pro tip

You can filter your logcat with adb logcat -s DaggerTrack

DaggerTrack automatically filters the components and their subcomponents and adds tracking logs to .class files so that you can see them in logcat at runtime whenever inject is called.

Installation Guide

Dagger Track is distributed via maven central. Dagger Track requires Gradle 6.0 or higher.

You can find the snapshots of development version in following sonatype. Include the following in your build.gradle.

Groovy

buildscript {
    repositories {
        mavenCentral()
        google()
        maven {
            url 'https://s01.oss.sonatype.org/content/repositories/snapshots'
        }
    }
    dependencies {
        classpath "me.amanjeet.daggertrack:dagger-track:1.0.6-SNAPSHOT"
    }
}

Kotlin

buildscript {
    repositories {
        mavenCentral()
        google()
        maven("https://s01.oss.sonatype.org/content/repositories/snapshots")
    }
    dependencies {
        classpath("me.amanjeet.daggertrack:dagger-track:1.0.6-SNAPSHOT")
    }
}

In your app level build.gradle apply the plugin:

If you use plugin DSL:

Groovy

plugins {
    id 'com.android.application' <---- Only works with android application & library 
    id 'me.amanjeet.daggertrack'
}

Kotlin

plugins {
    id("com.android.application") <---- Only works with android application & library 
    id("me.amanjeet.daggertrack")
}

or if you are using older versions of Gradle:

apply plugin: 'com.android.application' <---- Only works with android application & library 
apply plugin: 'me.amanjeet.daggertrack'

Note that DaggeTrack must be applied after the Android gradle plugin.

You need to tell dagger track which variant it should run on:

Groovy

daggerTrack {
    applyFor = ["debug"]
}

Kotlin

daggerTrack {
    applyFor = arrayOf("debug")
}

Integrate the dagger-track-clocks library in your app build.gradle, necessary for providing the different clocks during logging:

Groovy

implementation 'me.amanjeet.daggertrack:dagger-track-clocks:1.0.6-SNAPSHOT'

Kotlin

implementation("me.amanjeet.daggertrack:dagger-track-clocks:1.0.6-SNAPSHOT")

Sync your project and voila ✅ you are ready for tracking.

Internal Working

1. The plugin registers a gradle transform which helps you to perform transformations on java/kotlin bytecode.
2. The transform filters out all the components and their subcomponents in project.
3. Javassist exposes fluent APIs to perform operations easily on java byte code.
4. Through Javassist insertBefore and insertAfter API on a CtMethod all the relevant logs are embedded to byte code.
5. dagger-track-clock module has the clock APIs necessary to get wall clock time and CPU time at any instant.
6. To calculate CPU time at any instant we are using getrusage linux API provided in #include <sys/resource.h> header by default in all linux systems. For usage see the man page here.

Example of Generated Byte Code

For a given component, lets say DaggerApplicationComponent. The inject method for our application class will be transformed as follows:

public void inject(DaggerTrackApp daggerTrackApp) {
  long initialTime = DaggerTrackClocks.getUptimeMillis();
  long initialCpuTime = DaggerTrackClocks.getCpuTimeMillis();
  // injection here
  this.injectDaggerTrackApp(daggerTrackApp);
  Object var11 = null;
  long var12 = DaggerTrackClocks.getUptimeMillis();
  long var14 = DaggerTrackClocks.getCpuTimeMillis();
  // Logging starts here
  Log.d("DaggerTrack", "Total time of me.amanjeet.daggertrack.DaggerTrackApp: " + (var12 - initialTime) + "ms");
  Log.d("DaggerTrack", "Total On CPU time of me.amanjeet.daggertrack.DaggerTrackApp: " + (var14 - initialCpuTime) + "ms");
  Log.d("DaggerTrack", "Total Off CPU time of me.amanjeet.daggertrack.DaggerTrackApp: " + (var12 - initialTime - (var14 - initialCpuTime)) + "ms");
}

License

Copyright 2020 Amanjeet Singh

Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at

    http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.