物理上更改Maven pom.xml <properties>值

Question

I'm building a deployment pipeline for a couple of projects that depend on each other. Each build produces a new release build with a unique version number, which is deployed to a Maven repository. The downstream projects in the pipeline are then triggered with that new version as a dependency and built in like manner.

What I need is to change a property value in the pom.xml (or all poms in a multi module project) before building the project. For example in the following code the "0.1.200" would be changed to "0.1.345" (or whatever the latest build number is). Using system properties is not an option, because the updated pom will be deployed in a Maven repository, so the change must be persistent.

<properties>
    <foo.version>0.1.200</foo.version>
</properties>

<dependencies>
    <dependency>
        <groupId>com.example</groupId>
        <artifactId>foo</artifactId>
        <version>${foo.version}</version>
    </dependency>
</dependencies>

Is there some Maven plugin for doing this with one command line instruction? Else I will need to write a short script (eg in Ruby) which parses and changes all the pom.xml files in the project.

Answer 1

Yes, there exists a maven-replacer-plugin which is capable of this.

But if you're using some CI tool (which apparently you are) you could as well just stick with a custom script for this purpose.

Answer 2

The available Maven plugins didn't fit my purpose, so I ended up writing the following Ruby script that does exactly what I need:

#!/usr/bin/env ruby
require 'rexml/document'

def change_property(pom, key, value)
  property = pom.elements["/project/properties/#{key}"]
  if property != nil
    puts "    #{key}: #{property.text} -> #{value}"
    property.text = value
  end
end

unless ARGV.length == 2
  puts "Usage: #{$0} KEY VALUE"
  exit 1
end
KEY = ARGV.shift
VALUE = ARGV.shift

Dir.glob("**/pom.xml") { |pom_path|
  puts pom_path

  pom = REXML::Document.new(File.new(pom_path))
  pom.context[:attribute_quote] = :quote
  change_property(pom, KEY, VALUE)

  File.open(pom_path, 'wb') { |file|
    pom.write(file)
  }
  puts
}

Answer 3

Did you try this one?

Version Maven Plugin

Answer 4

I had a similar requirement. Besides updating the property under the /project/properties node, I also need to update the property under /project/profiles/properties node, so I modify Esko's script to support updating both cases. Meanwhile, it also supports updating multiple properties in one command so you don't have to run it multiple time if you need to update multiple properties in the same pom.xml.

#!/usr/bin/env ruby
require 'rexml/document'

def change_profile_property(pom, profile_id, key, value)
  property = pom.elements["/project/profiles/profile[id='#{profile_id}']/properties/#{key}"]
  if property != nil
    puts "    #{profile_id}-#{key}: #{property.text} -> #{value}"
    property.text = value
  end
end

def change_property(pom, key, value)
  property = pom.elements["/project/properties/#{key}"]
  if property != nil
    puts "    #{key}: #{property.text} -> #{value}"
    property.text = value
  end
end

if ARGV.length == 0
  puts "Usage: #{$0} KEY=VALUE [-profile <profile id>] KEY=VALUE"
  exit 1
end

# parse the command line argument to get the key/value
global_properties = Array.new
profile_properties= Array.new

profile = nil
loop { case ARGV[0]
  when '-profile' then  ARGV.shift; profile=ARGV.shift
  when nil then break
  else 
    kv_str = ARGV.shift
    if profile == nil
      global_properties.push(kv_str)
    else
      profile_properties.push(kv_str)
    end
  end; 
}

Dir.glob("**/pom.xml") { |pom_path|
  puts pom_path

  pom = REXML::Document.new(File.new(pom_path))
  pom.context[:attribute_quote] = :quote

  # updating the global properties
  if global_properties.length != 0
    for kv in global_properties
      kv_array = kv.split('=')
        if kv_array.length == 2
          change_property(pom, kv_array[0], kv_array[1])
        end
    end
  end

  # updating the properties in profile
  if profile_properties.length != 0
    for kv in profile_properties
      kv_array = kv.split('=')
      if kv_array.length == 2
        if profile != nil
          change_profile_property(pom, profile, kv_array[0], kv_array[1])
        end
    end
    end
  end

  File.open(pom_path, 'wb') { |file|
    pom.write(file)
  }
  puts
}

Answer 5

Flatten Maven Plugin can be used to update the variables. Let me explain with an example.

<groupId>groupid</groupId>
<artifactId>artifactid</artifactId>
<version>${ServiceVersion}</version>
<packaging>pom</packaging>

<properties>
    <foo.version>${ServiceVersion}</foo.version>
</properties>

In pom.xml, I'm using "ServiceVersion" to get the value during the build. The foo.version variable will be updated too during the build. Now, the foo.version variable can be used in any of the dependencies.

<dependencies>
    <dependency>
        <groupId>com.example</groupId>
        <artifactId>foo</artifactId>
        <version>${foo.version}</version>
    </dependency>
</dependencies>

So, finally include the Flatten Maven Plugin in the pom.xml

<plugin>
<groupId>org.codehaus.mojo</groupId>
<artifactId>flatten-maven-plugin</artifactId>
<version>1.0.0</version>
<configuration>
    <updatePomFile>true</updatePomFile>
</configuration>
 <executions>
    <execution>
        <id>flatten</id>
        <phase>process-resources</phase>
        <goals>
            <goal>flatten</goal>
        </goals>
    </execution>
    <execution>
      <id>flatten.clean</id>
      <phase>clean</phase>
      <goals>
        <goal>clean</goal>
      </goals>
    </execution>
  </executions>
</plugin>

Now provide the service version.

clean install -DServiceVersion=0.1.345