feat(container): add floating latest tag when publishing images

vars/container.groovy

@@ -18,8 +18,9 @@ String buildAndPublishImage(Map options = [:]) {
     String contextDir = options.get('contextDir', '.')
     String imageName = options.get('imageName', '')
     String gitRef = sh(returnStdout: true, script: 'git describe --always').trim()
-    
-    List<String> imageTags = options.get('imageTags', utils.getProjectVersionTags())
+
+    List<String> defaultImageTags = utils.getProjectVersionTags() + [ "${utils.getProjectVersionDefaultChannel()}-latest" ]
+    List<String> imageTags = options.get('imageTags', defaultImageTags)
     // Handle legacy imageTag parameter
     if (options.containsKey('imageTag')) {
         imageTags = [ options.get("imageTag", gitRef) ]

vars/utils.groovy

@@ -44,19 +44,36 @@ String getBuildUser() {
 }
 
 String getProjectVersionDefaultChannel() {
-    return env.BRANCH_NAME.toLowerCase().replaceAll('(_|-| )+', '')
+    switch (env.BRANCH_NAME) {
+        case 'develop':
+            return 'develop'
+        
+        case 'testing':
+        case 'staging':
+            return 'testing'
+
+        case 'stable':
+        case 'master':
+            return 'stable'
+        
+        default:
+            return env.BRANCH_NAME.toLowerCase().replaceAll('(_|-| )+', '')
+    }
 }
 
 String getProjectVersionShortChannel(String channel) {
     switch (channel) {
         case 'develop':
             return 'dev'
+        
         case 'testing':
         case 'staging':
             return 'tst'
+        
         case 'stable':
         case 'master':
             return 'stb'
+        
         default:
             return channel.toLowerCase().replaceAll('(a|e|i|o|u|y_|-| )+', '').take(3)
     }