Dependency resolution of Ivy artifacts does not support [type] token

[frisby]

Summary

There should be a way to customize every element of an Ivy artifact pattern. It appears that there is no way to specify a [type] that does not match [ext].

Context

Sample Ivy layout pattern, taken from the Gradle 3.3 User Guide:

repositories {
    ivy {
        url "http://repo.mycompany.com/repo"
        layout "pattern", {
            artifact "[module]/[revision]/[type]/[artifact].[ext]"
        }
    }
}

Fairly typical external dependency, also from the Gradle 3.3 User Guide:

dependencies {
    compile group: 'org.hibernate', name: 'hibernate-core', version: '3.6.7.Final'
}

(apply plugin: 'java' was specified in a previous Example, and presumed to remain in effect.)

In the above example, compile's group: parameter maps to [module], name: to [artifact], and version: to [revision]. Although I can find no documentation for it, the compile command appears to support ext:, which maps to Ivy's [ext] token.

Current Behavior

As near as I can tell, Gradle forces [type] to match [ext]. While very common, this is not guaranteed, which is why they are separate tokens to begin with.

Expected Behavior

There should be a way, either inline or via closure, to let [type] and [ext] operate independently of one another. Because they usually match, a default in which they are equal is fine.

In researching this, I've seen a few people draw comparisons to Maven's classifier. In these online discussions, Gradle developers have resisted this comparison, for reasons I presume are valid (this is not my area of expertise). Nevertheless, the [type] token should have some mechanism of support.

Steps to Reproduce (for bugs)

Using the examples above, an Ivy repository with the following directory layout should be sufficient to reproduce:

org.hibernate/
  |
  +--3.6.7.Final/
      |
      +--bin/
      |    |
      |    +--hibernate-core.jar
      |
      +--src/
           |
           +--hibernate-core.jar

The expectation would be that Hibernate's binary file would have a [type] of 'bin', while the source code would have a [type] of 'src'. The goal is to specify an external dependency that lets one download either .jar using the Ivy pattern in Gradle's User Guide.

(The only workaround I can see right now is to create separate patterns with each value for [type] hard-coded into it. This not only misses the point of having a token, it forces a download of every .jar, instead of "just sources" or "just binaries".)

I saw that the incubating IvyArtifact class has a type property, but it appears to be publish-only. I cannot find an equivalent concept for dependencies.

Your Environment

I am currently a developer working at a large enterprise with a strong division of roles between developers and operations. My access to the Ivy repository is restricted to an "end-user" role, so altering its configuration is not an option.

[eriwen]

Thank you very much for a thorough feature request @frisby. It sounds like you dug into the code here, would you be willing and able to submit a PR to address this? I believe it will ship to users like yourself faster.

[eriwen]

Note that this seems closely related to #1357. A contributor could make a very big impact by addressing both changes.

[stale]

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[stale]

This issue has been automatically closed due to inactivity. If you can reproduce this on a recent version of Gradle or if you have a good use case for this feature, please feel free to reopen the issue with steps to reproduce, a quick explanation of your use case or a high-quality pull request.