setting credentials in gradle via maven-publish

Question

I am using gradle v3.4 and have populated properties from a secrets.properties file (passed into project.ext) but when I use the variables in the credentials section, I get an error from nexus complianing about authentication issues which makes me believe the string interpolation is not working correctly. I can print the variable value just before the credentials section.

build.gradle

        maven {
            credentials {
println(project.nexusUsername)  //prints the value
                username '${project.nexusUsername}'
                password '${project.nexusPassword}'
            }
            if (project.version.endsWith("-SNAPSHOT")) {
                url "http://nexus.somewhere.com/repository/some-java-snapshot/"
            } else {
                url "http://nexus.somewhere.com/repository/some-java-release/"
            }
        }

Update I updated the credentials section above to use double quotes (not single) but that did not solve the issue. Single quotes are String literals - if you need String interpolation, you need to use double quotes in groovy.

Answer 1

The issue was how the properties was specified in the external properties file. I was using double quotes for the String values in the properties file and that was resulting in authentication failures. Once I removed the double quotes from the external properties file, I was able to publish to nexus.

Incorrect external properties file setting

someUsername="someuser"

Correct external properties file setting

someUsername=someuser

build.gradle

publishing {
    publications {
        shadow(MavenPublication) {
            from components.shadow
            groupId project.group
            artifactId project.artifactId
        }
    }
    repositories {
        maven {
            credentials {
                username project.someUsername
                password project.somePassword
            }
            if (project.version.endsWith("-SNAPSHOT")) {
                url project.someSnapshot
            } else {
                url project.someRelease
            }
        }
    }
}

this works.