Generate site using Jekyll via Docker

This makes site-building process more stable and less dependent on the environment, requiring only Docker to be installed locally.

Author: elizarov

gradle.properties

@@ -30,3 +30,6 @@ source_map_support_version=0.5.3
 # Settings
 kotlin.incremental.multiplatform=true
 kotlin.native.ignoreDisabledTargets=true
+
+# Site deneration
+jekyll_version=4.0

site/build.gradle

@@ -3,6 +3,7 @@
  */
 
 def buildDocsDir = "$buildDir/docs"
+def jekyllDockerImage = "jekyll/jekyll:$jekyll_version"
 
 task copyDocs(type: Copy, dependsOn: rootProject.getTasksByName("dokka", true)) {
     from (rootProject.getTasksByName("dokka", true).collect { "$it.project.buildDir/dokka" }) {
@@ -23,7 +24,17 @@ task site(type: Exec, description: 'Generate github pages', dependsOn: [copyDocs
     inputs.files(fileTree(buildDocsDir))
     outputs.dir("$buildDir/dist")
     workingDir file(buildDocsDir)
-    commandLine 'bundle', 'exec', 'jekyll', 'build'
+    commandLine 'docker', 'run', '--rm', "--volume=$buildDir:/srv/jekyll",
+        '-t', jekyllDockerImage,
+        '/bin/bash', '-c', 'cd docs; jekyll build'
+}
+
+// A useful task for local debugging -- serves a site locally
+task serve(type: Exec, dependsOn: [copyDocs, copyExampleFrontendJs]) {
+    commandLine 'docker', 'run', '--rm', "--volume=$buildDir:/srv/jekyll",
+        '-p', '8080:8080',
+        '-t', jekyllDockerImage,
+        '/bin/bash', '-c', 'cd docs; jekyll serve --host 0.0.0.0 --port 8080'
 }
 
 task clean(type: Delete) {

site/docs/Gemfile

@@ -10,8 +10,5 @@ destination: ../dist
 
 # Build settings
 markdown: kramdown
-exclude:
-  - Gemfile
-  - Gemfile.lock
 include:
   - package-list