Unable to turn off fetching the packageListUrl from network

[harri35]

Describe the bug
I have an Android library project with dokka plugin "org.jetbrains.dokka:dokka-gradle-plugin:1.4.20" and two separate tasks - one for library source and one for library source + tests.

I have a requirement that the project must be able to compile offline. For this we have a setup of a local maven repository that contains all the build script and compile dependencies. Also the ones that are needed for Dokka.

Everything else runs offline. But the dokka task every time fails with

* What went wrong:
Execution failed for task ':splitkey-service:dokkaHtml'.
> java.net.UnknownHostException: developer.android.com

I understand that this is because it tries to fetch the packageListUrl from online.
In order to avoid it I downloaded the package-list and added it locally:

externalDocumentationLink {
    url.set(URL("https://developer.android.com/reference/"))
    packageListUrl.set(URL("file:///${rootDir}/config/dokka-package-list/package-list"))
}

But this does not solve my issue, the build continues to fail.

What am I doing wrong?

Expected behaviour
Dokka is able to generate documentation without connecting to developer.android.com

To Reproduce

1. Use dokka plugin "org.jetbrains.dokka:dokka-gradle-plugin:1.4.20" for a Java/Kotlin mixed Android library project
2. Configure the dokka task as below
3. Turn your system offline
4. Run the task

Dokka configuration

// Main dokka task for Service
dokkaHtml.configure {
    dokkaSourceSets {
        named("main") {
            // Main source set conf
            outputDirectory.set(file(dokkaDocFilePath))
            includes.from(files("dokka_modules_main.md"))

            noJdkLink.set(true)
            noStdlibLink.set(true)
            noAndroidSdkLink.set(true)

            includeNonPublic.set(false)
            skipEmptyPackages.set(true)
            reportUndocumented.set(true)
            skipDeprecated.set(false)
            externalDocumentationLink {
                url.set(URL("https://developer.android.com/reference/"))
                packageListUrl.set(URL("file:///${rootDir}/config/dokka-package-list/package-list"))
            }
        }
    }
}

// Dokka task for Service tests
task dokkaHtmlTests(type: org.jetbrains.dokka.gradle.DokkaTask) {
    dokkaSourceSets {
        named("main") {
            outputDirectory.set(file(dokkaDocTestsFilePath))
            includes.from(files("dokka_modules_main.md", "dokka_modules_test.md"))
            sourceRoots.setFrom(file("src/main/java"))
            sourceRoots.from(file("src/androidTest/java"))

            noJdkLink.set(true)
            noStdlibLink.set(true)
            noAndroidSdkLink.set(true)

            includeNonPublic.set(true)
            skipEmptyPackages.set(true)
            reportUndocumented.set(true)
            skipDeprecated.set(false)

            externalDocumentationLink {
                url.set(URL("https://developer.android.com/reference/"))
                packageListUrl.set(URL("file:///${rootDir}/config/dokka-package-list/package-list"))
            }
        }
    }
}
}

Installation

• Operating system: Windows
• Build tool: Gradle 6.7.1
• Dokka version: 1.4.20

[harri35]

Followup:

I can't find this from anywhere in the documentation, but if I add

...
offlineMode.set(true)
...

then Dokka works offline perfectly.

So the full task in reference to the one in the initial post:

// Main dokka task for Service
dokkaHtml.configure {
    dokkaSourceSets {
        named("main") {
            // Main source set conf
            outputDirectory.set(file(dokkaDocFilePath))
            includes.from(files("dokka_modules_main.md"))

            // We need to run this in offline mode. We can't go fetching things from developer.android.com
            offlineMode.set(true)
            noJdkLink.set(false)
            noStdlibLink.set(false)
            noAndroidSdkLink.set(false)

            includeNonPublic.set(false)
            skipEmptyPackages.set(true)
            reportUndocumented.set(true)
            skipDeprecated.set(false)
            externalDocumentationLink {
                url.set(URL("https://developer.android.com/reference/"))
                // We need to run this in offline mode. We can't go fetching things from developer.android.com
                packageListUrl.set(URL("file:///${rootDir}/config/dokka-package-list/package-list"))
            }
        }
    }
}

[harri35]

If this is the expected behaviour then could you please document this somewhere in the Gradle plugin documentation? Currently, the offline mode is only mentioned on the CLI config.

[kamildoleglo]

That's strange actually. Are you sure this configuration is executed and you have no other source sets that Dokka might document? Turning off those links and adding a local one should be enough, offlineMode is more like a kill switch. Documented that in the Gradle plugin configuration nevertheless, thanks!

[tprochazka]

This is a related (not the same) issue
#1706

[vmishenev]

Currently, this is documented.

    // Used to prevent resolving package-lists online. When this option is set to true, only local files are resolved  
    offlineMode.set(false)