utils-build

An Ant build script for recursively downloading, building, and installing Maven dependencies. This is mainly useful for building projects with online CI tools if there are dependencies.

Say you have two projects, A and B, where B depends on A. Maven allows you to manage this dependency, so that the build process of B will download the latest published jar of project A when needed. However, when working at both A and B, we maybe do not want to publish an artifact for each commit. In this case, it might be useful if the latest commit of project A was used during the building process of project B. Maven cannot do that, it looks always for published artifacts. However, for continuous integration tools, especially for those tools which do the builds for us automatically whenever we commit, artifacts might be to coarse grained and we would sometimes use the latest sources instead.

This small utility project provides an Ant script which closes this gap: You can specify an Ant build.xml next to your Maven pom.xml. In this build.xml, you specify the projects which should be downloaded (from GitHub), built, and installed into the local Maven repository prior to building the actual project. We would thus put such a file into the root folder of project B and specify there that (the latest commit of the source code of) project A should first be downloaded, built, and installed before B is built.

By using Ant, we get somewhat platform independent: The same scripts work under Linux and Windows. However, we may need to install Ant first or update an existing installation (see below). For this, under Linux, I provide a BASH script as well (antWebInstallerLinux.sh).

It cannot parse the dependencies directly from your pom.xml, instead you need to specify them again as specified below.

1. Requirements

• Apache Ant 1.9.4 or later
• Maven version 3.0 and above

1.1. Under Linux

Some of the available CI systems (well, basically all) and Linux configuration ship with an older version of Ant and using their sudo apt-get install won't install the required version either. Therefore, we provide the script antWebInstallerLinux.sh which can download and install the required version of Ant. You can use it as follows in your builds:

wget "https://raw.githubusercontent.com/optimizationBenchmarking/utils-build/master/antWebInstallerLinux.sh"
chmod 755 antWebInstallerLinux.sh
sudo ./antWebInstallerLinux.sh

Some CI systems (such as CodeShip) do not grant you sudo. In that case, you can run ./antWebInstallerLinux.sh --haveSudo=false. The script will then simply install Ant into the current folder and create a symbolic link to the executable.

Sometimes (shippable, snap-ci, drone io) it may cause problems to uninstall an existing Ant installation. In this case, you can run ./antWebInstallerLinux.sh --purgeAnt=false. A best attempt will be made to redirect all Ant action to the new installation.

1.2. Under Windows

Under Windows, you can use chocolately to install all required software. Once you have chocolately on your system, you can install both Maven and Ant, update PATH and then simply run ant in the build folder.

cinst maven -Version 3.2.5
cinst ant -i -Version 1.9.6
SET PATH=C:\ProgramData\chocolatey\lib\ant\apache-ant-1.9.6\bin;C:\bin\apache-maven-3.2.5\bin;%JAVA_HOME%\bin;%PATH%

Under [AppVeyor(https://ci.appveyor.com/), you can add the following lines to the install section of your appveyor.yml.

ps: if(!(Test-Path -Path 'C:\bin\apache-maven-3.2.5\' )){ cinst maven -Version 3.2.5 }
ps: if(!(Test-Path -Path 'C:\ProgramData\chocolatey\lib\ant\apache-ant-1.9.6\' )){ cinst ant -i -Version 1.9.6 }
cmd: SET PATH=C:\ProgramData\chocolatey\lib\ant\apache-ant-1.9.6\bin;C:\bin\apache-maven-3.2.5\bin;%JAVA_HOME%\bin;%PATH%

1.3. Examples

You can check the build settings of our project utils-graphics as an example of how to use this with different CI systems. You can find the config files of the CI systems in the project root folder and/or click the build badges to get to systems which require manual configurations.

2. Invocation

You can put a build.xml file like the one in the next section below into the base directory of your Maven project. Invoke it as specified in order to recursively download, build, and install the dependencies of a Maven project from GitHub repositories.

• ant (auto-detect JDK and Maven, run tests for root project)
• ant -Djdk=PATH/TO/JDK (to specify the path to the JDK)
• ant -Dmaven=PATH/TO/MAVEN (to specify the path to Maven)
• ant -DskipTests=true (to skip the tests also of the root project)
• ant -DpassToMaven=XXXX (pass XXX as "-DXXX" to Maven (including recursive builds))
• any combination of the above, such as ant -Djdk=PATH/TO/JDK -Dmaven=PATH/TO/MAVEN

3. Example Script

If started as indicated above, the target build will be executed, which first downloads a help script (dependencyBuilder.xml). In the build target, you specify the main project (in this example, utils-graphics) which you want to build, i.e., the project in whose root folder you put the build.xml script, as githubProject attribute of the buildWithDependencies macro.

This macro takes another element, dependencies, where can specify nested dependency tags defining GitHub projects which need to be installed in order to compile the root project. In this example, there is one such required project, utils-base.

Both the buildWithDependencies as well as the dependency tag accept two attributes githubProject and githubGroup. Together, they allow you to select and project on GitHub. If githubGroup is not specified, it defaults to optimizationBenchmarking.

The buildWithDependencies macro is intended to work recursively, i.e., if the required project, too, defines a build.xml file, this file will be executed with Ant. It may then download and build additional dependencies. A dependency required by multiple projects is only built and installed once. If no build.xml file is specified, the project will be built with Maven.

<project basedir="." default="build">
	<import>
		<url url="https://raw.githubusercontent.com/optimizationBenchmarking/utils-build/master/dependencyBuilder.xml" />
	</import>

	<target name="build">
		<sequential>
			<buildWithDependencies githubProject="utils-graphics">
				<dependencies>
					<dependency githubProject="utils-base" />
				</dependencies>
			</buildWithDependencies>
		</sequential>
	</target>
</project>