# How to Resolve Specific Artifacts from a Module Dependency with Gradle

version 9.7.0-rc-2

Gradle resolves module dependencies by looking for metadata files (`.module`, `.pom`, or `ivy.xml`) and a default artifact (usually a JAR). If none of these files are found, the build fails. In some cases, you may need to customize how Gradle resolves artifacts.

## Why Use Custom Artifact Resolution?

You might need to tweak artifact resolution in the following scenarios:

- The dependency provides a non-standard artifact (e.g., a ZIP file) without metadata.

- The module metadata declares multiple artifacts (e.g., an Ivy dependency descriptor).

- You want to download only a specific artifact without transitive dependencies.

## Step 1: Resolving an Artifact Without Metadata

Let’s say you want to build a web application that uses JavaScript libraries, such as jQuery, and download them from a repository instead of checking them into version control.

Google Hosted Libraries provides open-source JavaScript libraries. Using artifact-only notation, you can fetch a JavaScript file like `jquery.js`.

The `@` character separates the dependency’s coordinates from the artifact’s file extension:

build.gradle.kts

    repositories {
        ivy {
            url = uri("https://ajax.googleapis.com/ajax/libs")
            patternLayout {
                artifact("[organization]/[revision]/[module].[ext]")
            }
            metadataSources {
                artifact()
            }
        }
    }

    configurations {
        create("js")
    }

    dependencies {
        "js"("jquery:jquery:3.2.1@js")
    }

build.gradle

    repositories {
        ivy {
            url = 'https://ajax.googleapis.com/ajax/libs'
            patternLayout {
                artifact '[organization]/[revision]/[module].[ext]'
            }
            metadataSources {
                artifact()
            }
        }
    }

    configurations {
        js
    }

    dependencies {
        js 'jquery:jquery:3.2.1@js'
    }

| Declaring dependencies with a custom extension (e.g. `@zip`, `@jar`, or `@custom`) disables metadata resolution. Gradle treats this as a request for a specific artifact, skipping variant-aware resolution and component metadata. You may need to provide metadata with a custom component metadata rule.

## Step 2: Resolving an Artifact with a Classifier

Some libraries provide multiple variations or flavors of an artifact. In Java, a library may publish:

- A compiled artifact with class files.

- A separate artifact containing source code.

- Another one with Javadocs.

Similarly, in JavaScript, libraries often have:

- An uncompressed version.

- A minified version (optimized for production).

To specify a particular variation, you can use a classifier. In Gradle, classifiers allow you to fetch a specific artifact within a module.

Instead of downloading the uncompressed `jquery.js` file, you can fetch the minified version (`jquery.min.js`) by specifying the classifier `min`:

build.gradle.kts

    repositories {
        ivy {
            url = uri("https://ajax.googleapis.com/ajax/libs")
            patternLayout {
                artifact("[organization]/[revision]/[module](.[classifier]).[ext]")
            }
            metadataSources {
                artifact()
            }
        }
    }

    configurations {
        create("js")
    }

    dependencies {
        "js"("jquery:jquery:3.2.1:min@js")
    }

build.gradle

    repositories {
        ivy {
            url = 'https://ajax.googleapis.com/ajax/libs'
            patternLayout {
                artifact '[organization]/[revision]/[module](.[classifier]).[ext]'
            }
            metadataSources {
                artifact()
            }
        }
    }

    configurations {
        js
    }

    dependencies {
        js 'jquery:jquery:3.2.1:min@js'
    }

## Summary

Gradle can fetch non-Java artifacts like JavaScript libraries from external repositories:

- Use artifact-only notation (`@`) when resolving dependencies that lack metadata.

- Use classifiers to specify different versions or variations of an artifact.