Activate Maven profiles in Cloud Manager

In some limited cases, you may need to vary your build process slightly when running inside Cloud Manager as opposed to when it runs on developer workstations. For these cases, Maven Profiles can be used to define how the build should be different in different environments, including Cloud Manager.

Activation of a Maven Profile inside the Cloud Manager build environment should be done by looking for CM_BUILD environment variable. Conversely, a profile intended to be used only outside of the Cloud Manager build environment should be done by looking for the absence of this variable.

For example, if you wanted to output a simple message only when the build is run inside Cloud Manager, you would do the following:

        <profile>
            <id>cmBuild</id>
            <activation>
                  <property>
                        <name>env.CM_BUILD</name>
                  </property>
            </activation>
            <build>
                <plugins>
                    <plugin>
                        <artifactId>maven-antrun-plugin</artifactId>
                        <version>1.8</version>
                        <executions>
                            <execution>
                                <phase>initialize</phase>
                                <configuration>
                                    <target>
                                        <echo>I'm running inside Cloud Manager!</echo>
                                    </target>
                                </configuration>
                                <goals>
                                    <goal>run</goal>
                                </goals>
                            </execution>
                        </executions>
                    </plugin>
                </plugins>
            </build>
        </profile>
NOTE
To test this profile on a developer workstation, you can either enable it on the command line (with -PcmBuild) or in your Integrated Development Environment (IDE).

And if you wanted to output a simple message only when the build is run outside of Cloud Manager, you would do the following:

        <profile>
            <id>notCMBuild</id>
            <activation>
                  <property>
                        <name>!env.CM_BUILD</name>
                  </property>
            </activation>
            <build>
                <plugins>
                    <plugin>
                        <artifactId>maven-antrun-plugin</artifactId>
                        <version>1.8</version>
                        <executions>
                            <execution>
                                <phase>initialize</phase>
                                <configuration>
                                    <target>
                                        <echo>I'm running outside Cloud Manager!</echo>
                                    </target>
                                </configuration>
                                <goals>
                                    <goal>run</goal>
                                </goals>
                            </execution>
                        </executions>
                    </plugin>
                </plugins>
            </build>
        </profile>

Password-protected Maven repository support

Artifacts from a password-protected Maven repository should be used cautiously because code deployed this way isn’t fully subjected to the quality checks enforced by Cloud Manager’s quality gates. Adobe also advises that you also deploy the Java sources and the whole project source code alongside with the binary.

TIP
Artifacts from password-protected Maven repositories should only be used in rare cases and for code not tied to AEM.

To use a password-protected Maven repository from Cloud Manager, specify the password (and optionally, the username) as a secret Pipeline Variable and then reference that secret inside a file named .cloudmanager/maven/settings.xml in the Git repository. This file follows the Maven Settings File schema.

When the Cloud Manager build process starts, the <servers> element in this file is merged into the default settings.xml file provided by Cloud Manager. Custom servers should not use server IDs that start with adobe and cloud-manager. Such IDs are considered reserved. Cloud Manager mirrors only those server IDs that match one of the specified prefixes or the default ID central.

With this file in place, the server ID would be referenced from inside a <repository> and/or <pluginRepository> element inside the pom.xml file. Generally, these <repository> and/or <pluginRepository> elements would be contained inside a Cloud Manager-specific profile, although that is not strictly necessary.

As an example, suppose that the repository is at https://repository.myco.com/maven2, the username Cloud Manager should use is cloudmanager and the password is secretword.

First, set the password as a secret on the pipeline:

$ aio cloudmanager:set-pipeline-variables PIPELINEID --secret CUSTOM_MYCO_REPOSITORY_PASSWORD secretword

Then reference the following from the .cloudmanager/maven/settings.xml file:

<?xml version="1.0" encoding="UTF-8"?>
<settings xmlns="http://maven.apache.org/SETTINGS/1.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
        xsi:schemaLocation="http://maven.apache.org/SETTINGS/1.0.0 http://maven.apache.org/xsd/settings-1.0.0.xsd">
    <servers>
        <server>
            <id>myco-repository</id>
            <username>cloudmanager</username>
            <password>${env.CUSTOM_MYCO_REPOSITORY_PASSWORD}</password>
        </server>
    </servers>
</settings>

And finally reference the server id inside the pom.xml file:

<profiles>
    <profile>
        <id>cmBuild</id>
        <activation>
                <property>
                    <name>env.CM_BUILD</name>
                </property>
        </activation>
        <build>
            <repositories>
                <repository>
                    <id>myco-repository</id>
                    <name>MyCo Releases</name>
                    <url>https://repository.myco.com/maven2</url>
                    <snapshots>
                        <enabled>false</enabled>
                    </snapshots>
                    <releases>
                        <enabled>true</enabled>
                    </releases>
                </repository>
            </repositories>
            <pluginRepositories>
                <pluginRepository>
                    <id>myco-repository</id>
                    <name>MyCo Releases</name>
                    <url>https://repository.myco.com/maven2</url>
                    <snapshots>
                        <enabled>false</enabled>
                    </snapshots>
                    <releases>
                        <enabled>true</enabled>
                    </releases>
                </pluginRepository>
            </pluginRepositories>
        </build>
    </profile>
</profiles>

Deploy sources

It is a good practice to deploy the Java sources alongside with the binary to a Maven repository.

Configure the maven-source-plugin in your project:

        <plugin>
            <groupId>org.apache.maven.plugins</groupId>
            <artifactId>maven-source-plugin</artifactId>
            <executions>
                <execution>
                    <id>attach-sources</id>
                    <goals>
                        <goal>jar-no-fork</goal>
                    </goals>
                </execution>
            </executions>
        </plugin>

Deploy project sources

It is good practice to deploy the whole project source alongside with the binary to a Maven repository. Doing so allows rebuilding the exact artifact.

Configure the maven-assembly-plugin in your project:

        <plugin>
            <groupId>org.apache.maven.plugins</groupId>
            <artifactId>maven-assembly-plugin</artifactId>
            <executions>
                <execution>
                    <id>project-assembly</id>
                    <phase>package</phase>
                    <goals>
                        <goal>single</goal>
                    </goals>
                    <configuration>
                        <descriptorRefs>
                            <descriptorRef>project</descriptorRef>
                        </descriptorRefs>
                    </configuration>
                </execution>
            </executions>
        </plugin>

Skip content packages

In Cloud Manager, builds may produce any number of content packages. For a variety of reasons, it may be desirable to produce a content package but not deploy it. For example, this approach can be useful when you build content packages solely for testing or when another step in the build process repackages them. That is, as a sub-package of another package.

To accommodate these scenarios, Cloud Manager looks for a property named cloudManagerTarget in the properties of built content packages. If this property is set to none, the package is skipped and not deployed. The mechanism to set this property depends on the way the build is producing the content package. For example, with the filevault-maven-plugin you would configure the plug-in like this:

        <plugin>
            <groupId>org.apache.jackrabbit</groupId>
            <artifactId>filevault-package-maven-plugin</artifactId>
            <extensions>true</extensions>
            <configuration>
                <properties>
                    <cloudManagerTarget>none</cloudManagerTarget>
                </properties>
        <!-- other configuration -->
            </configuration>
        </plugin>

With the content-package-maven-plugin, it is similar:

        <plugin>
            <groupId>com.day.jcr.vault</groupId>
            <artifactId>content-package-maven-plugin</artifactId>
            <extensions>true</extensions>
            <configuration>
                <properties>
                    <cloudManagerTarget>none</cloudManagerTarget>
                </properties>
        <!-- other configuration -->
            </configuration>
        </plugin>

Build Artifact reuse

In many cases, the same code is deployed to multiple AEM environments. Where possible, Cloud Manager avoids rebuilding the code base when it detects that the same Git commit is used in multiple full-stack pipeline executions.

When an execution is started, the current HEAD commit for the branch pipeline is extracted. The commit hash is visible in the UI and by way of the API. When the build step completes successfully, the resulting artifacts are stored based on that commit hash and may be reused in subsequent pipeline executions.

Packages are reused across pipelines if they are in the same program. When looking for packages that can be reused, AEM disregards branches and reuses artifacts across branches.

When a reuse occurs, the build and code quality steps are effectively replaced with the results from the original execution. The log file for the build step lists the artifacts and the execution information that was used to build them originally.

The following is an example of such log output.

The following build artifacts were reused from the prior execution 4 of pipeline 1 which used commit f6ac5e6943ba8bce8804086241ba28bd94909aef:
build/aem-guides-wknd.all-2021.1216.1101633.0000884042.zip (content-package)
build/aem-guides-wknd.dispatcher.cloud-2021.1216.1101633.0000884042.zip (dispatcher-configuration)

The log of the code quality step contains similar information.

Examples

Example 1

Consider that your program has two development pipelines:

  • Pipeline 1 on branch foo
  • Pipeline 2 on branch bar

Both branches are on the same commit ID.

  1. Running pipeline 1 first builds the packages normally.
  2. Then running pipeline 2 reuses packages created by pipeline 1.

Example 2

Consider that your program has two branches: Branch foo and Branch bar.

Both branches have the same commit ID.

  1. A development pipeline builds and executes foo.
  2. Subsequently, a production pipeline builds and executes bar.

In this case, the artifact from foo is reused for the production pipeline because the same commit hash was identified.

Opt out

If desired, the reuse behavior can be disabled for specific pipelines by setting the pipeline variable CM_DISABLE_BUILD_REUSE to true. If this variable is set, the commit hash is still extracted. The resulting artifacts are stored for later use, but any previously stored artifacts are not reused. To understand this behavior, consider the following scenario:

  1. A new pipeline is created.
  2. The pipeline is executed (execution #1) and the current HEAD commit is becdddb. The execution is successful and the resulting artifacts are stored.
  3. The CM_DISABLE_BUILD_REUSE variable is set.
  4. The pipeline is re-executed without changing code. Although there are stored artifacts associated with becdddb, they are not reused due to the CM_DISABLE_BUILD_REUSE variable.
  5. The code is changed and the pipeline is executed. The HEAD commit is now f6ac5e6. The execution is successful and the resulting artifacts are stored.
  6. The CM_DISABLE_BUILD_REUSE variable is deleted.
  7. The pipeline is re-executed without changing the code. Because there are stored artifacts associated with f6ac5e6, those artifacts are reused.