[MNG-8286] Add a condition profile based on a simple expressions

• Type: Sub-task
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 4.0.0-rc-1
• Component/s: Profiles
• Assignee: Guillaume Nodet
• Reporter: Guillaume Nodet
• Created: 03/Oct/24 18:00
• Updated: 2 days ago 20:39
• Resolved: 2 days ago 20:37

Description

GitHub Pull Request: https://github.com/apache/maven/pull/1771

Condition-Based Profile Activation in Maven

In addition to the traditional activation mechanisms (JDK version, OS properties, file existence, etc.), Maven now supports a powerful condition-based activation through the condition field. This new mechanism allows for more flexible and expressive profile activation rules.

Condition Syntax

The condition is specified as a string expression that can include various functions, comparisons, and logical operators.
Some key features include:

Property access: ${property.name}
Comparison operators: ==, !=, <, >, <=, >=
Logical operators: && (AND), || (OR), not(...)
Functions: exists(...), missing(...), matches(...), inrange(...), and more

Supported Functions

The following functions are supported in condition expressions:

• length(string): Returns the length of the given string.
• upper(string): Converts the string to uppercase.
• lower(string): Converts the string to lowercase.
• substring(string, start, [end]): Returns a substring of the given string.
• indexOf(string, substring): Returns the index of the first occurrence of substring in string, or -1 if not found.
• contains(string, substring): Checks if the string contains the substring.
• matches(string, regex): Checks if the string matches the given regular expression.
• not(condition): Negates the given condition.
• if(condition, trueValue, falseValue): Returns trueValue if the condition is true, falseValue otherwise.
• exists(path): Checks if a file matching the given glob pattern exists.
• missing(path): Checks if a file matching the given glob pattern does not exist.
• inrange(version, range): Checks if the given version is within the specified version range.

Supported properties

The following properties are supported in expressions:

• project.basedir: The project directory
• project.rootDirectory: The root directory of the project
• project.artifactId: The artifactId of the project
• project.packaging: The packaging of the project
• user properties
• system properties (including environment variables prefixed with env.)

Examples

• JDK version range: inrange(${java.version}, '[11,)') (JDK 11 or higher)
• OS check: ${os.name} == 'windows'
• File existence: exists('${project.basedir}/src/** /*.xsd')
• Property check: ${my.property} != 'some-value'
• Regex matching: matches(${os.version}, '.*aws')
• Complex condition: ${os.name} == 'windows' && ${os.arch} != 'amd64' && inrange(${os.version}, '[10,)')
• String length check: length(${user.name}) > 5
• Substring with version: substring(${java.version}, 0, 3) == '1.8'
• Using indexOf: indexOf(${java.version}, '-') > 0
• Conditional logic: if(contains(${java.version}, ''), substring(${java.version}, 0, indexOf(${java.version}, '')), ${java.version})

This flexible condition mechanism allows for more precise control over profile activation, enabling developers to create profiles that respond to a wide range of environmental factors and project states.

This will be triggered using a new profile activation in the 4.1.0 model:

<profile>
  <activation>
    <condition>inrange(${maven.version}, '[4,)')</condition>
  </activation>
</profile>

Issue Links

• contains: MNG-3328 Allow multiple profile activation properties
• contains: MNG-7577 Ability to activate profile based on multiple property values
• fixes: MNG-8124 Allow regex usage in any profile activation key/value
• relates to: MNG-5909 Activating a profile based on the existence of multiple files is not possible
• links to: GitHub Pull Request #1771