Set platform from PR labels

If PR specifies a ci-platform label, override the default
test platform.

Signed-off-by: Pablo Chacin <pchacin@suse.com>

ci/jenkins/pipelines/prs/skuba-test.Jenkinsfile

@@ -4,12 +4,16 @@
  *   - Basic skuba deployment, bootstrapping, and adding nodes to a cluster
  */
 
+
+// Platform for pr tests.
+def platform = 'vmware'
+
 // Branch specific repo
 def branch_repo = ""
 
 // Set the agent platform label. Cannot be set using the environment variables
 // because agent labels are evaluated before environment is set
-labels=''
+def labels=''
 node('caasp-team-private-integration') {
     stage('set-labels') {
         sh 'env'
@@ -19,13 +23,23 @@ node('caasp-team-private-integration') {
            validResponseCodes: "200")
 
         if (response.status == 200) {
-              def pr = readJSON text: response.content
-              pr.labels.findAll {
-                it.name.startsWith("ci-label:")
-              }.each{
-                def label = it.name.split(":")[1]
-                labels = labels + " && " + label 
-              }
+            def pr = readJSON text: response.content
+
+            // set al pr specific labels
+            pr.labels.findAll {
+              it.name.startsWith("ci-label:")
+            }.each{
+              def label = it.name.split(":")[1]
+              labels = labels + " && " + label 
+            }
+
+            // check if the PR request an specific test platform
+            def pr_platform_label = pr.labels.find {
+               it.name.startsWith("ci-platform")
+            }
+            if (pr_platform_label != null) {
+                platform = pr_platform_label.name.split(":")[1]
+            }
         }
     }
 }
@@ -37,7 +51,7 @@ pipeline {
         SKUBA_BINPATH = '/home/jenkins/go/bin/skuba'
         VMWARE_ENV_FILE = credentials('vmware-env')
         GITHUB_TOKEN = credentials('github-token')
-        PLATFORM = 'vmware'
+        PLATFORM = "${platform}" 
         TERRAFORM_STACK_NAME = "${BUILD_NUMBER}-${JOB_NAME.replaceAll("/","-")}".take(70)
         PR_CONTEXT = 'jenkins/skuba-test'
         PR_MANAGER = 'ci/jenkins/pipelines/prs/helpers/pr-manager'