Add option to show preview URL for the PR in the GitHub comment

README.md

@@ -77,6 +77,10 @@ savage {
     //   pushing the branch to GitHub, Savage will assume something went wrong and delete the branch to
     //   keep the test repo's branches tidy.
     travis-timeout = 2 hours
+    // Include a link to the "preview URL" of the PR in the GitHub comment?
+    //   Probably only makes sense if you're Bootstrap.
+    //   Otherwise, you'll need to edit the hardcoded URL template string.
+    show-preview-urls = false
     // Full name of GitHub repo to watch for new pull requests
     github-repo-to-watch = "twbs/bootstrap"
     // Full name of GitHub repo to push test branches to

src/main/resources/application.conf

@@ -26,6 +26,7 @@ savage {
     squelch-invalid-http-logging = true
     set-commit-status = true
     travis-timeout = 2 hours
+    show-preview-urls = true
     github-repo-to-watch = "twbs/bootstrap"
     github-test-repo = "twbs-savage/bootstrap"
     allowed-base-branches = [ "master", "v4-dev", "v3-dev" ]

src/main/scala/com/getbootstrap/savage/server/PullRequestCommenter.scala

@@ -15,12 +15,14 @@ class PullRequestCommenter extends GitHubActorWithLogging {
     case PullRequestBuildResult(prNum, commitSha, buildUrl, succeeded) => {
       val mythicalStatus = if (succeeded) { "**CONFIRMED**" } else { "**BUSTED**" }
       val plainStatus = if (succeeded) { "**Tests passed.**" } else { "**Tests failed.**" }
+      val previewInfo = if (settings.ShowPreviewUrls) { "Docs preview: http://preview.twbsapps.com/c/${commitSha.sha}" } else { "" }
 
       val commentMarkdown = s"""
         |${plainStatus} Automated cross-browser testing via Sauce Labs and Travis CI shows that the JavaScript changes in this pull request are: ${mythicalStatus}
         |
         |Commit: ${commitSha.sha}
         |Build details: ${buildUrl}
+        |${previewInfo}
         |
         |(*Please note that this is a [fully automated](https://github.com/twbs/savage) comment.*)
       """.stripMargin

src/main/scala/com/getbootstrap/savage/server/Settings.scala

@@ -30,6 +30,7 @@ class SettingsImpl(config: Config) extends Extension {
   val TrustedOrganizations: Set[String] = config.getStringList("savage.trusted-orgs").asScala.toSet
   val SetCommitStatus: Boolean = config.getBoolean("savage.set-commit-status")
   val TravisTimeout: FiniteDuration = config.getFiniteDuration("savage.travis-timeout")
+  val ShowPreviewUrls: Boolean = config.getBoolean("savage.show-preview-urls")
 }
 object Settings extends ExtensionId[SettingsImpl] with ExtensionIdProvider {
   override def lookup() = Settings