avram/andevcon-gradle.html

## andevcon-gradle.html
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class: center, middle, inverse

# Embracing Gradle
### Practical build automation for the Android world

Avram Lyon<br>Scopely

AnDevCon Boston, 2014<br><br>http://tiny.cc/gradle

---
class: center

# March-July 2012

## One title, one codebase

Debug / Release

Google / Amazon

Free / Paid
## =
## 6 Builds
---
class: center, middle, inverse

# the road to gradle is paved with home-brew and make-do
## this is Scopely's road there

---
# `rake` and `ant`
.footnote[why use one build tool when you can use two?]

* `goog-free-prod.yaml`:
```yaml
app_name: Dice with Buddies Free
facebook_app_id: 12345678912
```

* `config/AndroidManifest.xml.erb`:
```xml
<application app:label=<%=app_name%> ...>
```
* `config/strings.xml.erb`:
```xml
<string name="facebook_app_id"><%=facebook_app_id%></string>
```

```sh
$ rake configure env=goog-free-prod
    + config/goog-free-prod.yaml
      config/amzn-paid-prod.yaml
 config/AndroidManifest.xml.erb  => AndroidManifest.xml
 config/strings.xml.erb          => res/values/strings.xml
$ ant clean release
```

???
So we had all this building nicely on TeamCity, and on people's boxes.

---
# `ant`-`rake`r

1. Worked
2. `rake` and `ant` experts certainly would have done better
3. i18n… Not really.
4. Dependency management? What's that?
5. All builds had assets and jars for all versions
6. IDE treated as standard Ant-style project
  * But it wouldn't build until you `rake`d


---
# More builds
## January 2013
* More codebases
  1. Android-Core (90%+ of code)
  2. Dice-Android (assets, code tweaks)
  3. MiniGolf-Android (+ more)
* Unity components!
* More developers!

---
class: middle
# Complication multiplies!

```sh
# generate templated files (Manifest, resources, etc.)
rake configure env=goog-free-prod
# Build Unity *.so's and assets, copy them into the Android project
rake unity unzipUnity
# Build the game APK
ant release
```
* Versioning specified as argument to `rake configure`
* `build.xml` fairly standard, with addition of simple package renaming task

---
class: middle
# The Good
* Encapsulated magic in `rake configure` and `rake unity`
* Arbitrary Ruby code in templates

---
class: middle, inverse
# The Bad
* Encapsulated magic in `rake configure` and `rake unity`
* Arbitrary Ruby code in templates
* Ruby? How did that happen?
* See previous slides.

???
We had investigated other options, and tried some preliminary work with Maven and even with pre-Google I/O Gradle. But Ant worked.
---
class: center

# May 2013

## Three titles

Debug / Release

Google / Amazon

Free / Paid
## =
## 18 Builds

---
class: middle, center, inverse
# Google I/O 2013

# Gradle + Android Studio

---
class: middle
# Decision to Move
1. Flavors
1. Flavors
1. Testing for library projects
1. Flavors
1. Extensibility
1. Dependency management
1. Embrace the future
1. Flavors

???
Build system migrations have very substantial mental costs... We moved in July, after starting investigation in May.

---
```xml
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="<%=@gamepackage%>"
    android:versionCode="<%=@versionCode%>"
    android:installLocation="auto"
    android:versionName="<%=@version%>" >

    <uses-sdk android:minSdkVersion="8" android:targetSdkVersion="17" />
    <uses-permission android:name="android.permission.INTERNET"/>
    <uses-permission android:name="android.permission.READ_PHONE_STATE"/>
    <uses-permission android:name="android.permission.ACCESS_NETWORK_STATE"/>
    <uses-permission android:name="android.permission.ACCESS_WIFI_STATE"/>
    <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/>
    <uses-permission android:name="android.permission.READ_CONTACTS" />
    <uses-permission android:name="android.permission.SEND_SMS" />
    <uses-permission android:name="android.permission.RECEIVE_BOOT_COMPLETED"/>
    <uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION"/>
    <!-- Start game-specific permissions -->
<% ERB.new(open(@merge_permissions).read(), nil, nil, "@mergeperm").result(binding)  %>
<%=@mergeperm%>
    <!-- End game-specific permissions -->

    <% if @store == "GoogleCheckout" %>
      <uses-permission android:name="com.android.vending.BILLING" />
      <uses-permission android:name="com.android.vending.CHECK_LICENSE" />

      <!-- Used for GCM, a Google-only service -->
      <uses-permission android:name="com.google.android.c2dm.permission.RECEIVE" />
      <uses-permission android:name="android.permission.GET_ACCOUNTS" />
      <uses-permission android:name="android.permission.WAKE_LOCK" />

      <permission android:name="<%=@package%>.permission.C2D_MESSAGE" android:protectionLevel="signature" />
    <uses-permission android:name="<%=@package%>.permission.C2D_MESSAGE" />
    <% end %>
```

---
# Typical values
```yaml
# Game-defining settings
version: 2.8.0
game: Dice
gamepackage: com.withbuddies.dice
gameurlscheme: dwb

# Build settings
merge_activities: config/AndroidManifest.merge_activities.erb
merge_permissions: config/AndroidManifest.merge_permissions.erb
intent_filter_overrides: []
```
`amzn-free-test.yaml`
```yaml
package: com.withbuddies.dice.free
store: AmazonMarketplace
```

(it keeps on going)

---
class: middle, inverse
# Converting to Gradle equivalents

We didn't actually convert everything immediately.

???
We first added Gradle as a drop-in optional build system, which we only required for some tests.

---
class: middle
## Gradle starts with sane, opionionated configuration by convention

```
/src/main/java
/src/main/res
/src/main/assets
/src/main/AndroidManifest.xml

/src/androidTest/java
/src/androidTest/res
...
```
---
# Ant convention

```
/project/src
/project/res
/project/assets
/project/AndroidManifest.xml

/testProject/src
/testProject/res
/testProject/AndroidManifest.xml
```

---
# Make Gradle bend to Ant's will

```groovy
android {
  sourceSets {
        main {
            manifest {
                srcFile 'project/AndroidManifest.xml'
            }
            java {
                srcDirs = ['library/src']
            }
            res {
                srcDirs = ['library/res']
            }
            assets {
                srcDirs = ['library/assets']
            }
            // --snip--
        }

        androidTest {
          // no manifest
          java {
            srcDirs = ['test/src']
          }
          res {
            srcDirs = ['test/res']
          }
        }
    }
}
```

---
# Custom package name

```groovy
android {
    flavorGroups "store", "bundle", "config"

    productFlavors {
        free {
            flavorGroup "bundle"
            packageName 'com.withbuddies.dice.free'
        }
        paid {
            flavorGroup "bundle"
            packageName 'com.withbuddies.dice'
        }
        ...
    }
}
```

Build with:
`./gradlew installFreeRelease`

???
We'll see flavors again. They are extremely useful but they are, unfortunately, just part of the Android plugin for Gradle, and are not available in standard Java projects.

---
class: middle, inverse
# But… GCM is broken!

---
# Manifest fragments
`src/free/AndroidManifest.xml`:
```xml
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android">
    <application>
        <receiver android:name="com.withbuddies.core.push.GCMReceiver" android:permission="com.google.android.c2dm.permission.SEND" >
            <intent-filter>
                <action android:name="com.google.android.c2dm.intent.RECEIVE" />
                <action android:name="com.google.android.c2dm.intent.REGISTRATION" />
                <category android:name="com.withbuddies.dice.free" />
            </intent-filter>
        </receiver>
    </application>

    <permission android:name="com.withbuddies.dice.free.permission.C2D_MESSAGE" android:protectionLevel="signature" />
    <uses-permission android:name="com.withbuddies.dice.free.permission.C2D_MESSAGE" />
</manifest>
```
`src/paid/AndroidManifest.xml` (trimmed out some detail):
```xml
    <category android:name="com.withbuddies.dice" />
    <permission android:name="com.withbuddies.dice.permission.C2D_MESSAGE" android:protectionLevel="signature" />
    <uses-permission android:name="com.withbuddies.dice.permission.C2D_MESSAGE" />
```

---
# Intelligent "new" manifest merging

Optional as of Android plugin 0.10

```groovy
android {
  useOldManifestMerger false
}
```

`src/main/AndroidManifest.xml`:
```xml
<manifest xmlns:android="http://schemas.android.com/apk/res/android">
    <application>
        <receiver android:name="com.withbuddies.core.push.GCMReceiver" android:permission="com.google.android.c2dm.permission.SEND" >
            <intent-filter>
                <action android:name="com.google.android.c2dm.intent.RECEIVE" />
                <action android:name="com.google.android.c2dm.intent.REGISTRATION" />
                <category android:name="${packageName}" />
            </intent-filter>
        </receiver>
    </application>

    <permission android:name="${packageName}.permission.C2D_MESSAGE" android:protectionLevel="signature" />
    <uses-permission android:name="${packageName}.permission.C2D_MESSAGE" />
</manifest>
```

Information: http://tools.android.com/tech-docs/new-build-system/user-guide/manifest-merger

???
This is the kind of killer feature that justified the move to Gradle in the first place-- for us at Scopely, it is one of the things that we had had a grudging respect for in the rake+ant days.

This kind of merge has rather complete documentation, and it can do a lot


---
# Amazon vs. Google
```groovy
android {
    flavorGroups "store", "bundle", "config"

    productFlavors {
        goog {
            flavorGroup "store"
        }
        amzn {
            flavorGroup "store"
        }
        ...
    }
}
```

---
# Amazon vs. Google
`src/goog/AndroidManifest.xml`:
```xml
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android">
      <uses-permission android:name="com.android.vending.BILLING" />
      <uses-permission android:name="com.android.vending.CHECK_LICENSE" />

      <!-- Used for GCM, a Google-only service -->
      <uses-permission android:name="com.google.android.c2dm.permission.RECEIVE" />
      <uses-permission android:name="android.permission.GET_ACCOUNTS" />
      <uses-permission android:name="android.permission.WAKE_LOCK" />
</manifest>
```
Because Amazon will reject you if you have the GCM or billing permissions in your manifest.

---
# How do I know what build I am?

## Old school: Set value in generated properties file or resource file
```yaml
DEBUG=<%= @mode == "test" %>
BUNDLE=<%=@bundle%>   # dicefree or dicepaid
MODE=<%=@mode%>
TARGET=<%=@target%>
```

Likely use case is controlling ads or premium features.

---
## Slightly newer school: Override a resource
* `src/main/res/values/configuration.xml`:

```xml
<?xml version="1.0" encoding="utf-8"?>
<resources>
    <string name="configuration_bundle">dicefree</string>
</resources>
```

* `src/paid/res/values/paid_configuration.xml`:

```xml
<?xml version="1.0" encoding="utf-8"?>
<resources>
    <string name="configuration_bundle">dicepaid</string>
</resources>
```

* `src/free/res/values/free_configuration.xml`:

```xml
<?xml version="1.0" encoding="utf-8"?>
<resources>
    <string name="configuration_bundle">dicefree</string>
</resources>
```

???
Note that resources always override on a per-resources basis, not on a per-file basis. The naming of `free_configuration` and `paid_configuration` is purely for disambiguation in the IDE.

---
## Newest school: Key off `BuildConfig`

Remember old `BuildConfig.DEBUG`? It has family.

```java
public static final String BUILD_TYPE = "debug";
public static final String FLAVOR = "googFree";
public static final String FLAVOR_store = "goog";
public static final String FLAVOR_bundle = "free";
```

This also means no overhead retrieving from properties files or resources.

## Other uses

```groovy
def buildTime = new Date().format("yyyy-MM-dd'T'HH:mm'Z'", TimeZone.getTimeZone("UTC"))

android {
    defaultConfig {
          buildConfigField "String", "BUILD_TIME", "\"$buildTime\""
    }
}
```

---
# Versioning

```xml
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="<%=@gamepackage%>"
    android:versionCode="<%=@versionCode%>"
    android:installLocation="auto"
    android:versionName="<%=@version%>" >
```

## Version Code and Version

```groovy
android {
  versionCode getVersionCode()
  versionName getVersionName()
}
```

---
# Getting groovy with versions
```groovy
def getVersionName = { ->
    return project.hasProperty('versionName') ? versionName : null
}

 /*
  * Make from version name and build number
  */
def versionCodeFromVersionName = { ->
    if (project.hasProperty('versionName')) {
        String[] parts = versionName.tokenize(".");
        int[] numbers = new int[parts.length + 1];
        for (int i = 0; i < parts.length; i++)
            numbers[i] = Integer.parseInt(parts[i].trim());
        if (project.hasProperty('buildNumber')) {
            numbers[parts.length] = Integer.parseInt(buildNumber) % 10000;
        }
        int number = 0;
        number += numbers[0] * 1000000
        number += numbers[1] * 100000
        number += numbers[2] * 10000
        number += numbers[3]
        return number
    } else {
        return -1
    }
}
```

???
Uses the {@literal versionName} and {@literal buildNumber} properties of the project to construct an informative version code. Per the Android definition of the version code, it must be a 32-bit positive integer, and subsequently uploaded APKs of a single app must have monotonically increasing version codes. The version name and build number together provide a fairly good guarantee of this.

---
# Getting groovy with versions

Properties can be set in a properties file:

`gradle.properties`:
```yaml
versionName=3.1.4
```

Or on the command line:

`./gradlew installGoogFreeRelease -PbuildNumber=35`

---
# Multiproject builds

* `./build.gradle` – Frequently empty, unless specifying defaults.
* `./settings.gradle` – Enumeration of all projects that will be used with `compile project(":Core-Project")`

## "Project" dependencies
```groovy
include 'ads-sdk'
include 'Core-Project'
include 'Game1'
include 'anotherDirectory/anotherProject'
```

Argument to `include` must be the path to the dependency's `build.gradle`

---
# Typical defaults for parent project

```groovy
subprojects {
    buildscript {
        repositories {
            mavenCentral()
        }
        dependencies {
            classpath 'com.android.tools.build:gradle:0.10.2'
        }
    }

    apply plugin: 'android'

    compileSdkVersion 19

    buildToolsVersion "19.1.0"

    // Configures the dexer. Our projects frequently exhaust the default heap allocated to the dexer
    dexOptions {
        incremental true
        javaMaxHeapSize "4g"
        preDexLibraries = "true".equals(System.getProperty("pre-dex", "true"))
    }

    defaultConfig {
        minSdkVersion 14
        targetSdkVersion 19
    }
}
```
---
# Pulling code into a "plugin"

```groovy
apply from: '../client-build-scripts/Android/Universal/base_build.gradle'
```

`base_build.gradle`:
```groovy
task assembleFiles(type: Copy, dependsOn: )
    from(jar.outputs.files) {
        into 'lib'
    }

    from(configurations.runtime) {
        into 'lib'
    }

    from('build/scripts') {
        into 'bin'
    }

    from("$rootProject.projectDir/templates") {
        into 'scripts'
        include 'upstart-template.conf.template'
        rename { file -> "${project.name}.conf" }
        expand(serviceName: project.name)

    }
}
```

???
Uses Groovy strings (should look familiar from the next-gen manifest merging)
Uses Groovy templating

---
# More on Groovy templating (optional)
(Non-Android example)
```upstart
# Upstart service configuration
# Generated from /templates/upstart-template.conf.template

description "titan-${serviceName}"

start on filesystem and started networking
stop on shutdown

script
    export HOME="/opt/scopely"

    echo \$\$ > /var/run/${serviceName}.pid
    exec sudo -u ubuntu \$HOME/${serviceName}/bin/${serviceName} >> /var/log/${serviceName}.sys.log 2>&1
end script

pre-start script
    echo "[`date -u +%Y-%m-%dT%T.%3NZ`] (sys) Starting" >> /var/log/${serviceName}.sys.log
end script

pre-stop script
    rm /var/run/titan-${serviceName}.pid
    echo "[`date -u +%Y-%m-%dT%T.%3NZ`] (sys) Stopping" >> /var/log/${serviceName}.sys.log
end script
```

---
class: middle, inverse
# A real plugin
See https://github.com/ajlyon/unity-gradle-plugin

### Plugin docs:
See http://www.gradle.org/docs/current/userguide/custom_plugins.html

---
# Plugins you don't need to write
* `android-sdk-manager` @ `'com.jakewharton.sdkmanager:gradle-plugin:0.10.+'`

Automatically downloads the specified versions of Android and build tools. Perfect for CI.

* `android-test` @ `'org.robolectric.gradle:gradle-android-test-plugin:0.10.0'`

Runs Robolectric tests on the JVM. Run by Pivotal, which took over from Jake Wharton.

---
# Gradle Support
## IDEs
1. IntelliJ / Android Studio
1. Eclipse. Not worth trying at present; can grok the `java` plugin but not `android`

## Build Servers
First class support:
1. TeamCity
1. Jenkins (+ Gradle plugin, of course)

Things move fast -- wait a bit before bumping versions of IDE or Gradle.


???
This is one of the most vital areas at present-- growing quickly.
---
# Future directions for Gradle
1. NDK development
1. Gradle and LibGDX: http://www.badlogicgames.com/wordpress/?p=3336
1. Gradle for C#
  * Defunct project by Unity3d: https://github.com/Unity-Technologies/kaizen
1. Gradle for Obj-C

---
# Further reading:
* The Android plugin manual, but it occasionally is a bit behind: http://tools.android.com/tech-docs/new-build-system/user-guide
* Every new version. Read the release notes carefully.
* Gradle User Guide: http://www.gradle.org/docs/current/userguide/userguide.html
* Xavier Ducrohet on Google+: https://plus.google.com/+XavierDucrohet/posts
* Google Developer Tools on Google+: https://plus.google.com/communities/114791428968349268860
* adt-dev community on Google Groups: https://groups.google.com/forum/#!forum/adt-dev

???
Communication can be a weakness in this project... It has a history of moving faster than its docs and than its announcements.

---
# Questions?
# Feedback
eventmobi.com/andevconboston
# Me
@ajlyon<br>ajlyon@gmail.com<br>
Scopely is hiring!
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  </body>
</html>
	<!DOCTYPE html>
	<html>
	<head>
	<title>Title</title>
	<meta http-equiv="Content-Type" content="text/html; charset=UTF-8"/>
	<style type="text/css">
	@import url(http://fonts.googleapis.com/css?family=Yanone+Kaffeesatz);
	@import url(http://fonts.googleapis.com/css?family=Droid+Serif:400,700,400italic);
	@import url(http://fonts.googleapis.com/css?family=Ubuntu+Mono:400,700,400italic);
	body {
	font-family: 'Droid Serif';
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	font-family: 'Yanone Kaffeesatz';
	font-weight: 400;
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	.remark-slide-content h3 { font-size: 1.6em; }
	.footnote {
	position: absolute;
	bottom: 3em;
	}
	li p { line-height: 1.25em; }
	.red { color: #fa0000; }
	.large { font-size: 2em; }
	a, a > code {
	color: rgb(249, 38, 114);
	text-decoration: none;
	}
	code {
	-moz-border-radius: 5px;
	-web-border-radius: 5px;
	background: #e7e8e2;
	border-radius: 5px;
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	.remark-code, .remark-inline-code { font-family: 'Ubuntu Mono'; }
	.remark-code-line-highlighted { background-color: #373832; }
	.pull-left {
	float: left;
	width: 47%;
	}
	.pull-right {
	float: right;
	width: 47%;
	}
	.pull-right ~ p {
	clear: both;
	}
	#slideshow .slide .content code {
	font-size: 0.8em;
	}
	#slideshow .slide .content pre code {
	font-size: 0.9em;
	padding: 15px;
	}
	.inverse {
	background: #272822;
	color: #777872;
	text-shadow: 0 0 20px #333;
	}
	.inverse h1, .inverse h2 {
	color: #f3f3f3;
	line-height: 0.8em;
	}

	/* Slide-specific styling */
	#slide-inverse .footnote {
	bottom: 12px;
	left: 20px;
	}
	#slide-how .slides {
	font-size: 0.9em;
	position: absolute;
	top: 151px;
	right: 140px;
	}
	#slide-how .slides h3 {
	margin-top: 0.2em;
	}
	#slide-how .slides .first, #slide-how .slides .second {
	padding: 1px 20px;
	height: 90px;
	width: 120px;
	-moz-box-shadow: 0 0 10px #777;
	-webkit-box-shadow: 0 0 10px #777;
	box-shadow: 0 0 10px #777;
	}
	#slide-how .slides .first {
	background: #fff;
	position: absolute;
	top: 20%;
	left: 20%;
	z-index: 1;
	}
	#slide-how .slides .second {
	position: relative;
	background: #fff;
	z-index: 0;
	}

	/* Two-column layout */
	.left-column {
	color: #777;
	width: 20%;
	height: 92%;
	float: left;
	}
	.left-column h2:last-of-type, .left-column h3:last-child {
	color: #000;
	}
	.right-column {
	width: 75%;
	float: right;
	padding-top: 1em;
	}
	</style>
	</head>
	<body>
	<textarea id="source">

	class: center, middle, inverse

	# Embracing Gradle
	### Practical build automation for the Android world

	Avram Lyon<br>Scopely

	AnDevCon Boston, 2014<br><br>http://tiny.cc/gradle

	---
	class: center

	# March-July 2012

	## One title, one codebase

	Debug / Release

	Google / Amazon

	Free / Paid
	## =
	## 6 Builds
	---
	class: center, middle, inverse

	# the road to gradle is paved with home-brew and make-do
	## this is Scopely's road there

	---
	# `rake` and `ant`
	.footnote[why use one build tool when you can use two?]

	* `goog-free-prod.yaml`:
	```yaml
	app_name: Dice with Buddies Free
	facebook_app_id: 12345678912
	```

	* `config/AndroidManifest.xml.erb`:
	```xml
	<application app:label=<%=app_name%> ...>
	```
	* `config/strings.xml.erb`:
	```xml
	<string name="facebook_app_id"><%=facebook_app_id%></string>
	```

	```sh
	$ rake configure env=goog-free-prod
	+ config/goog-free-prod.yaml
	config/amzn-paid-prod.yaml
	config/AndroidManifest.xml.erb => AndroidManifest.xml
	config/strings.xml.erb => res/values/strings.xml
	$ ant clean release
	```

	???
	So we had all this building nicely on TeamCity, and on people's boxes.

	---
	# `ant`-`rake`r

	1. Worked
	2. `rake` and `ant` experts certainly would have done better
	3. i18n… Not really.
	4. Dependency management? What's that?
	5. All builds had assets and jars for all versions
	6. IDE treated as standard Ant-style project
	* But it wouldn't build until you `rake`d


	---
	# More builds
	## January 2013
	* More codebases
	1. Android-Core (90%+ of code)
	2. Dice-Android (assets, code tweaks)
	3. MiniGolf-Android (+ more)
	* Unity components!
	* More developers!

	---
	class: middle
	# Complication multiplies!

	```sh
	# generate templated files (Manifest, resources, etc.)
	rake configure env=goog-free-prod
	# Build Unity *.so's and assets, copy them into the Android project
	rake unity unzipUnity
	# Build the game APK
	ant release
	```
	* Versioning specified as argument to `rake configure`
	* `build.xml` fairly standard, with addition of simple package renaming task

	---
	class: middle
	# The Good
	* Encapsulated magic in `rake configure` and `rake unity`
	* Arbitrary Ruby code in templates

	---
	class: middle, inverse
	# The Bad
	* Encapsulated magic in `rake configure` and `rake unity`
	* Arbitrary Ruby code in templates
	* Ruby? How did that happen?
	* See previous slides.

	???
	We had investigated other options, and tried some preliminary work with Maven and even with pre-Google I/O Gradle. But Ant worked.
	---
	class: center

	# May 2013

	## Three titles

	Debug / Release

	Google / Amazon

	Free / Paid
	## =
	## 18 Builds

	---
	class: middle, center, inverse
	# Google I/O 2013

	# Gradle + Android Studio

	---
	class: middle
	# Decision to Move
	1. Flavors
	1. Flavors
	1. Testing for library projects
	1. Flavors
	1. Extensibility
	1. Dependency management
	1. Embrace the future
	1. Flavors

	???
	Build system migrations have very substantial mental costs... We moved in July, after starting investigation in May.

	---
	```xml
	<?xml version="1.0" encoding="utf-8"?>
	<manifest xmlns:android="http://schemas.android.com/apk/res/android"
	package="<%=@gamepackage%>"
	android:versionCode="<%=@versionCode%>"
	android:installLocation="auto"
	android:versionName="<%=@version%>" >

	<uses-sdk android:minSdkVersion="8" android:targetSdkVersion="17" />
	<uses-permission android:name="android.permission.INTERNET"/>
	<uses-permission android:name="android.permission.READ_PHONE_STATE"/>
	<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE"/>
	<uses-permission android:name="android.permission.ACCESS_WIFI_STATE"/>
	<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/>
	<uses-permission android:name="android.permission.READ_CONTACTS" />
	<uses-permission android:name="android.permission.SEND_SMS" />
	<uses-permission android:name="android.permission.RECEIVE_BOOT_COMPLETED"/>
	<uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION"/>
	<!-- Start game-specific permissions -->
	<% ERB.new(open(@merge_permissions).read(), nil, nil, "@mergeperm").result(binding) %>
	<%=@mergeperm%>
	<!-- End game-specific permissions -->

	<% if @store == "GoogleCheckout" %>
	<uses-permission android:name="com.android.vending.BILLING" />
	<uses-permission android:name="com.android.vending.CHECK_LICENSE" />

	<!-- Used for GCM, a Google-only service -->
	<uses-permission android:name="com.google.android.c2dm.permission.RECEIVE" />
	<uses-permission android:name="android.permission.GET_ACCOUNTS" />
	<uses-permission android:name="android.permission.WAKE_LOCK" />

	<permission android:name="<%=@package%>.permission.C2D_MESSAGE" android:protectionLevel="signature" />
	<uses-permission android:name="<%=@package%>.permission.C2D_MESSAGE" />
	<% end %>
	```

	---
	# Typical values
	```yaml
	# Game-defining settings
	version: 2.8.0
	game: Dice
	gamepackage: com.withbuddies.dice
	gameurlscheme: dwb

	# Build settings
	merge_activities: config/AndroidManifest.merge_activities.erb
	merge_permissions: config/AndroidManifest.merge_permissions.erb
	intent_filter_overrides: []
	```
	`amzn-free-test.yaml`
	```yaml
	package: com.withbuddies.dice.free
	store: AmazonMarketplace
	```

	(it keeps on going)

	---
	class: middle, inverse
	# Converting to Gradle equivalents

	We didn't actually convert everything immediately.

	???
	We first added Gradle as a drop-in optional build system, which we only required for some tests.

	---
	class: middle
	## Gradle starts with sane, opionionated configuration by convention

	```
	/src/main/java
	/src/main/res
	/src/main/assets
	/src/main/AndroidManifest.xml

	/src/androidTest/java
	/src/androidTest/res
	...
	```
	---
	# Ant convention

	```
	/project/src
	/project/res
	/project/assets
	/project/AndroidManifest.xml

	/testProject/src
	/testProject/res
	/testProject/AndroidManifest.xml
	```

	---
	# Make Gradle bend to Ant's will

	```groovy
	android {
	sourceSets {
	main {
	manifest {
	srcFile 'project/AndroidManifest.xml'
	}
	java {
	srcDirs = ['library/src']
	}
	res {
	srcDirs = ['library/res']
	}
	assets {
	srcDirs = ['library/assets']
	}
	// --snip--
	}

	androidTest {
	// no manifest
	java {
	srcDirs = ['test/src']
	}
	res {
	srcDirs = ['test/res']
	}
	}
	}
	}
	```

	---
	# Custom package name

	```groovy
	android {
	flavorGroups "store", "bundle", "config"

	productFlavors {
	free {
	flavorGroup "bundle"
	packageName 'com.withbuddies.dice.free'
	}
	paid {
	flavorGroup "bundle"
	packageName 'com.withbuddies.dice'
	}
	...
	}
	}
	```

	Build with:
	`./gradlew installFreeRelease`

	???
	We'll see flavors again. They are extremely useful but they are, unfortunately, just part of the Android plugin for Gradle, and are not available in standard Java projects.

	---
	class: middle, inverse
	# But… GCM is broken!

	---
	# Manifest fragments
	`src/free/AndroidManifest.xml`:
	```xml
	<?xml version="1.0" encoding="utf-8"?>
	<manifest xmlns:android="http://schemas.android.com/apk/res/android">
	<application>
	<receiver android:name="com.withbuddies.core.push.GCMReceiver" android:permission="com.google.android.c2dm.permission.SEND" >
	<intent-filter>
	<action android:name="com.google.android.c2dm.intent.RECEIVE" />
	<action android:name="com.google.android.c2dm.intent.REGISTRATION" />
	<category android:name="com.withbuddies.dice.free" />
	</intent-filter>
	</receiver>
	</application>

	<permission android:name="com.withbuddies.dice.free.permission.C2D_MESSAGE" android:protectionLevel="signature" />
	<uses-permission android:name="com.withbuddies.dice.free.permission.C2D_MESSAGE" />
	</manifest>
	```
	`src/paid/AndroidManifest.xml` (trimmed out some detail):
	```xml
	<category android:name="com.withbuddies.dice" />
	<permission android:name="com.withbuddies.dice.permission.C2D_MESSAGE" android:protectionLevel="signature" />
	<uses-permission android:name="com.withbuddies.dice.permission.C2D_MESSAGE" />
	```

	---
	# Intelligent "new" manifest merging

	Optional as of Android plugin 0.10

	```groovy
	android {
	useOldManifestMerger false
	}
	```

	`src/main/AndroidManifest.xml`:
	```xml
	<manifest xmlns:android="http://schemas.android.com/apk/res/android">
	<application>
	<receiver android:name="com.withbuddies.core.push.GCMReceiver" android:permission="com.google.android.c2dm.permission.SEND" >
	<intent-filter>
	<action android:name="com.google.android.c2dm.intent.RECEIVE" />
	<action android:name="com.google.android.c2dm.intent.REGISTRATION" />
	<category android:name="${packageName}" />
	</intent-filter>
	</receiver>
	</application>

	<permission android:name="${packageName}.permission.C2D_MESSAGE" android:protectionLevel="signature" />
	<uses-permission android:name="${packageName}.permission.C2D_MESSAGE" />
	</manifest>
	```

	Information: http://tools.android.com/tech-docs/new-build-system/user-guide/manifest-merger

	???
	This is the kind of killer feature that justified the move to Gradle in the first place-- for us at Scopely, it is one of the things that we had had a grudging respect for in the rake+ant days.

	This kind of merge has rather complete documentation, and it can do a lot


	---
	# Amazon vs. Google
	```groovy
	android {
	flavorGroups "store", "bundle", "config"

	productFlavors {
	goog {
	flavorGroup "store"
	}
	amzn {
	flavorGroup "store"
	}
	...
	}
	}
	```

	---
	# Amazon vs. Google
	`src/goog/AndroidManifest.xml`:
	```xml
	<?xml version="1.0" encoding="utf-8"?>
	<manifest xmlns:android="http://schemas.android.com/apk/res/android">
	<uses-permission android:name="com.android.vending.BILLING" />
	<uses-permission android:name="com.android.vending.CHECK_LICENSE" />

	<!-- Used for GCM, a Google-only service -->
	<uses-permission android:name="com.google.android.c2dm.permission.RECEIVE" />
	<uses-permission android:name="android.permission.GET_ACCOUNTS" />
	<uses-permission android:name="android.permission.WAKE_LOCK" />
	</manifest>
	```
	Because Amazon will reject you if you have the GCM or billing permissions in your manifest.

	---
	# How do I know what build I am?

	## Old school: Set value in generated properties file or resource file
	```yaml
	DEBUG=<%= @mode == "test" %>
	BUNDLE=<%=@bundle%> # dicefree or dicepaid
	MODE=<%=@mode%>
	TARGET=<%=@target%>
	```

	Likely use case is controlling ads or premium features.

	---
	## Slightly newer school: Override a resource
	* `src/main/res/values/configuration.xml`:

	```xml
	<?xml version="1.0" encoding="utf-8"?>
	<resources>
	<string name="configuration_bundle">dicefree</string>
	</resources>
	```

	* `src/paid/res/values/paid_configuration.xml`:

	```xml
	<?xml version="1.0" encoding="utf-8"?>
	<resources>
	<string name="configuration_bundle">dicepaid</string>
	</resources>
	```

	* `src/free/res/values/free_configuration.xml`:

	```xml
	<?xml version="1.0" encoding="utf-8"?>
	<resources>
	<string name="configuration_bundle">dicefree</string>
	</resources>
	```

	???
	Note that resources always override on a per-resources basis, not on a per-file basis. The naming of `free_configuration` and `paid_configuration` is purely for disambiguation in the IDE.

	---
	## Newest school: Key off `BuildConfig`

	Remember old `BuildConfig.DEBUG`? It has family.

	```java
	public static final String BUILD_TYPE = "debug";
	public static final String FLAVOR = "googFree";
	public static final String FLAVOR_store = "goog";
	public static final String FLAVOR_bundle = "free";
	```

	This also means no overhead retrieving from properties files or resources.

	## Other uses

	```groovy
	def buildTime = new Date().format("yyyy-MM-dd'T'HH:mm'Z'", TimeZone.getTimeZone("UTC"))

	android {
	defaultConfig {
	buildConfigField "String", "BUILD_TIME", "\"$buildTime\""
	}
	}
	```

	---
	# Versioning

	```xml
	<manifest xmlns:android="http://schemas.android.com/apk/res/android"
	package="<%=@gamepackage%>"
	android:versionCode="<%=@versionCode%>"
	android:installLocation="auto"
	android:versionName="<%=@version%>" >
	```

	## Version Code and Version

	```groovy
	android {
	versionCode getVersionCode()
	versionName getVersionName()
	}
	```

	---
	# Getting groovy with versions
	```groovy
	def getVersionName = { ->
	return project.hasProperty('versionName') ? versionName : null
	}

	/*
	* Make from version name and build number
	*/
	def versionCodeFromVersionName = { ->
	if (project.hasProperty('versionName')) {
	String[] parts = versionName.tokenize(".");
	int[] numbers = new int[parts.length + 1];
	for (int i = 0; i < parts.length; i++)
	numbers[i] = Integer.parseInt(parts[i].trim());
	if (project.hasProperty('buildNumber')) {
	numbers[parts.length] = Integer.parseInt(buildNumber) % 10000;
	}
	int number = 0;
	number += numbers[0] * 1000000
	number += numbers[1] * 100000
	number += numbers[2] * 10000
	number += numbers[3]
	return number
	} else {
	return -1
	}
	}
	```

	???
	Uses the {@literal versionName} and {@literal buildNumber} properties of the project to construct an informative version code. Per the Android definition of the version code, it must be a 32-bit positive integer, and subsequently uploaded APKs of a single app must have monotonically increasing version codes. The version name and build number together provide a fairly good guarantee of this.

	---
	# Getting groovy with versions

	Properties can be set in a properties file:

	`gradle.properties`:
	```yaml
	versionName=3.1.4
	```

	Or on the command line:

	`./gradlew installGoogFreeRelease -PbuildNumber=35`

	---
	# Multiproject builds

	* `./build.gradle` – Frequently empty, unless specifying defaults.
	* `./settings.gradle` – Enumeration of all projects that will be used with `compile project(":Core-Project")`

	## "Project" dependencies
	```groovy
	include 'ads-sdk'
	include 'Core-Project'
	include 'Game1'
	include 'anotherDirectory/anotherProject'
	```

	Argument to `include` must be the path to the dependency's `build.gradle`

	---
	# Typical defaults for parent project

	```groovy
	subprojects {
	buildscript {
	repositories {
	mavenCentral()
	}
	dependencies {
	classpath 'com.android.tools.build:gradle:0.10.2'
	}
	}

	apply plugin: 'android'

	compileSdkVersion 19

	buildToolsVersion "19.1.0"

	// Configures the dexer. Our projects frequently exhaust the default heap allocated to the dexer
	dexOptions {
	incremental true
	javaMaxHeapSize "4g"
	preDexLibraries = "true".equals(System.getProperty("pre-dex", "true"))
	}

	defaultConfig {
	minSdkVersion 14
	targetSdkVersion 19
	}
	}
	```
	---
	# Pulling code into a "plugin"

	```groovy
	apply from: '../client-build-scripts/Android/Universal/base_build.gradle'
	```

	`base_build.gradle`:
	```groovy
	task assembleFiles(type: Copy, dependsOn: )
	from(jar.outputs.files) {
	into 'lib'
	}

	from(configurations.runtime) {
	into 'lib'
	}

	from('build/scripts') {
	into 'bin'
	}

	from("$rootProject.projectDir/templates") {
	into 'scripts'
	include 'upstart-template.conf.template'
	rename { file -> "${project.name}.conf" }
	expand(serviceName: project.name)

	}
	}
	```

	???
	Uses Groovy strings (should look familiar from the next-gen manifest merging)
	Uses Groovy templating

	---
	# More on Groovy templating (optional)
	(Non-Android example)
	```upstart
	# Upstart service configuration
	# Generated from /templates/upstart-template.conf.template

	description "titan-${serviceName}"

	start on filesystem and started networking
	stop on shutdown

	script
	export HOME="/opt/scopely"

	echo \$\$ > /var/run/${serviceName}.pid
	exec sudo -u ubuntu \$HOME/${serviceName}/bin/${serviceName} >> /var/log/${serviceName}.sys.log 2>&1
	end script

	pre-start script
	echo "[`date -u +%Y-%m-%dT%T.%3NZ`] (sys) Starting" >> /var/log/${serviceName}.sys.log
	end script

	pre-stop script
	rm /var/run/titan-${serviceName}.pid
	echo "[`date -u +%Y-%m-%dT%T.%3NZ`] (sys) Stopping" >> /var/log/${serviceName}.sys.log
	end script
	```

	---
	class: middle, inverse
	# A real plugin
	See https://github.com/ajlyon/unity-gradle-plugin

	### Plugin docs:
	See http://www.gradle.org/docs/current/userguide/custom_plugins.html

	---
	# Plugins you don't need to write
	* `android-sdk-manager` @ `'com.jakewharton.sdkmanager:gradle-plugin:0.10.+'`

	Automatically downloads the specified versions of Android and build tools. Perfect for CI.

	* `android-test` @ `'org.robolectric.gradle:gradle-android-test-plugin:0.10.0'`

	Runs Robolectric tests on the JVM. Run by Pivotal, which took over from Jake Wharton.

	---
	# Gradle Support
	## IDEs
	1. IntelliJ / Android Studio
	1. Eclipse. Not worth trying at present; can grok the `java` plugin but not `android`

	## Build Servers
	First class support:
	1. TeamCity
	1. Jenkins (+ Gradle plugin, of course)

	Things move fast -- wait a bit before bumping versions of IDE or Gradle.


	???
	This is one of the most vital areas at present-- growing quickly.
	---
	# Future directions for Gradle
	1. NDK development
	1. Gradle and LibGDX: http://www.badlogicgames.com/wordpress/?p=3336
	1. Gradle for C#
	* Defunct project by Unity3d: https://github.com/Unity-Technologies/kaizen
	1. Gradle for Obj-C

	---
	# Further reading:
	* The Android plugin manual, but it occasionally is a bit behind: http://tools.android.com/tech-docs/new-build-system/user-guide
	* Every new version. Read the release notes carefully.
	* Gradle User Guide: http://www.gradle.org/docs/current/userguide/userguide.html
	* Xavier Ducrohet on Google+: https://plus.google.com/+XavierDucrohet/posts
	* Google Developer Tools on Google+: https://plus.google.com/communities/114791428968349268860
	* adt-dev community on Google Groups: https://groups.google.com/forum/#!forum/adt-dev

	???
	Communication can be a weakness in this project... It has a history of moving faster than its docs and than its announcements.

	---
	# Questions?
	# Feedback
	eventmobi.com/andevconboston
	# Me
	@ajlyon<br>ajlyon@gmail.com<br>
	Scopely is hiring!
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