Reverse Library precedence during loading to prevent library overriding

Version_2.adoc

@@ -50,12 +50,17 @@ As JTE grows in adoption, there is plenty that can be done to improve our abilit
 
 == Feature Development
 
+* [] https://github.com/jenkinsci/templating-engine-plugin/pull/132[Allow for reversal of library sources traversal]
+* [x] https://github.com/jenkinsci/templating-engine-plugin/issues/111[move JTE behavior feature flags into a root level `jte` block in the pipeline configuration]
+* [x] https://github.com/jenkinsci/templating-engine-plugin/issues/100[Pipeline Job: added SCM pipeline configuration and template]
+* [x] https://github.com/jenkinsci/templating-engine-plugin/pull/101[JTE pipelines can survive an ungraceful restart now]
+* [x] https://github.com/jenkinsci/templating-engine-plugin/pull/98[Added pipelineConfig reserved variable]
 * [x] https://github.com/jenkinsci/templating-engine-plugin/issues/46[Add support for Library Resources]
 * [x] https://github.com/jenkinsci/templating-engine-plugin/issues/97[Field-level pipeline configuration governance]
 * [x] https://github.com/jenkinsci/templating-engine-plugin/issues/79[Standardize on autowired variables - remove the Lifecycle Hook context parameter in favor of an autowired variable]
 * [x] https://github.com/jenkinsci/templating-engine-plugin/issues/72[Document the StageContext functionality to pass arguments to steps run as part of a Stage]
-* [ ] https://github.com/jenkinsci/templating-engine-plugin/issues/62[Introduce step namespacing so that multiple steps with the same name can be loaded via a less-strict initialization process configurable by the user]
-* [ ] https://github.com/jenkinsci/templating-engine-plugin/issues/84[Improve overall initialization logging for JTE to help users debug issues]
+* [x] https://github.com/jenkinsci/templating-engine-plugin/issues/62[Introduce step namespacing so that multiple steps with the same name can be loaded via a less-strict initialization process configurable by the user]
+* [x] https://github.com/jenkinsci/templating-engine-plugin/issues/84[Improve overall initialization logging for JTE to help users debug issues]
 * [ ] https://github.com/jenkinsci/templating-engine-plugin/issues/23[Investigate whether or not JTE can integrate with Jenkins Pipeline's Declarative Syntax]
 
 

docs/modules/pipeline-templating/pages/configuration_files.adoc

@@ -22,6 +22,7 @@ jte{ <1>
     allow_scm_jenkinsfile = true
     pipeline_template = "some_template"
     permissive_initialization = false
+    reverse_library_resolution = false
 }
 
 template_methods{} <2>
@@ -59,6 +60,10 @@ keywords{} <7>
 | Whether or not JTE will allow a naming collision within the binding. For example, two library's that both contribute a step by the same name or a keyword and application environment by the same name.
 | `false`
 
+| `reverse_library_resolution`
+| Normally, JTE resolves libraries based on the library sources from the highest governance tier down towards the job, xref:governance:library_selection.adoc[default library selection]. This flag, if enabled, reverses the library search order
+| `false`
+
 |===
 
 [WARNING]

src/main/groovy/org/boozallen/plugins/jte/init/PipelineDecorator.groovy

@@ -106,10 +106,9 @@ class PipelineDecorator extends InvisibleAction {
     }
 
     String determinePipelineTemplate(){
-        LinkedHashMap pipelineConfig = config.getConfig()
         WorkflowJob job = getJob()
         FlowDefinition flowDefinition = job.getDefinition()
-        JteBlockWrapper jteBlockWrapper = (pipelineConfig.jte ?: [:]) as JteBlockWrapper
+        JteBlockWrapper jteBlockWrapper = config.jteBlockWrapper
         if (flowDefinition instanceof AdHocTemplateFlowDefinition){
             String template = flowDefinition.getTemplate(flowOwner)
             if(template){
@@ -172,14 +171,16 @@ class PipelineDecorator extends InvisibleAction {
         String pipeline_template = null
         Boolean allow_scm_jenkinsfile = true
         Boolean permissive_initialization = false
+        Boolean reverse_library_resolution = false
 
         static LinkedHashMap getSchema(){
             return [
                 fields: [
                     optional: [
                         allow_scm_jenkinsfile: Boolean,
                         pipeline_template: String,
-                        permissive_initialization: Boolean
+                        permissive_initialization: Boolean,
+                        reverse_library_resolution: Boolean
                     ]
                 ]
             ]

src/main/groovy/org/boozallen/plugins/jte/init/governance/config/dsl/PipelineConfigurationObject.groovy

@@ -15,6 +15,7 @@
 */
 package org.boozallen.plugins.jte.init.governance.config.dsl
 
+import org.boozallen.plugins.jte.init.PipelineDecorator
 import org.boozallen.plugins.jte.util.TemplateLogger
 import org.codehaus.groovy.runtime.InvokerHelper
 import org.jenkinsci.plugins.workflow.flow.FlowExecutionOwner
@@ -38,6 +39,10 @@ class PipelineConfigurationObject implements Serializable{
         this.flowOwner = flowOwner
     }
 
+    PipelineDecorator.JteBlockWrapper getJteBlockWrapper(){
+        return (config.jte ?: [:]) as PipelineDecorator.JteBlockWrapper
+    }
+
     PipelineConfigurationObject plus(PipelineConfigurationObject child){
         /*
             If this is the first call to join, then there is no pre-existing

src/main/groovy/org/boozallen/plugins/jte/init/primitives/TemplateBindingFactory.groovy

@@ -39,7 +39,7 @@ class TemplateBindingFactory {
 
     static TemplateBinding create(FlowExecutionOwner flowOwner, PipelineConfigurationObject config){
         invoke("validateConfiguration", flowOwner, config)
-        JteBlockWrapper jte = (config.getConfig().jte ?: [:]) as JteBlockWrapper
+        JteBlockWrapper jte = config.jteBlockWrapper
         TemplateBinding templateBinding = new TemplateBinding(flowOwner, jte.permissive_initialization)
         invoke("injectPrimitives", flowOwner, config, templateBinding)
         invoke("validateBinding", flowOwner, config, templateBinding)

src/main/groovy/org/boozallen/plugins/jte/init/primitives/injectors/LibraryStepInjector.groovy

@@ -54,6 +54,10 @@ import org.jenkinsci.plugins.workflow.job.WorkflowJob
         LinkedHashMap aggregatedConfig = config.getConfig()
         AggregateException errors = new AggregateException()
         List<LibraryProvider> providers = getLibraryProviders(flowOwner)
+        boolean reverseProviders = config.jteBlockWrapper.reverse_library_resolution
+        if(reverseProviders) {
+            providers = providers.reverse()
+        }
         ConfigValidator validator = new ConfigValidator(flowOwner)
         aggregatedConfig[KEY].each { libName, libConfig ->
             LibraryProvider provider = providers.find{ provider ->
@@ -86,7 +90,12 @@ import org.jenkinsci.plugins.workflow.job.WorkflowJob
     @Override
     void injectPrimitives(FlowExecutionOwner flowOwner, PipelineConfigurationObject config, TemplateBinding binding){
         LinkedHashMap aggregatedConfig = config.getConfig()
+
         List<LibraryProvider> providers = getLibraryProviders(flowOwner)
+        boolean reverseProviders = config.jteBlockWrapper.reverse_library_resolution
+        if(reverseProviders) {
+            providers = providers.reverse()
+        }
         aggregatedConfig[KEY].each{ libName, libConfig ->
             LibraryProvider provider = providers.find{ provider ->
                 provider.hasLibrary(flowOwner, libName)

src/test/groovy/org/boozallen/plugins/jte/init/PipelineDecoratorSpec.groovy

@@ -63,12 +63,14 @@ class PipelineDecoratorSpec extends Specification{
         then:
         jte.allow_scm_jenkinsfile == expected_allow
         jte.pipeline_template == expected_template
+        jte.permissive_initialization == permissive
+        jte.reverse_library_resolution == reverse_libs
 
         where:
-        config | expected_allow | expected_template
-        [:]   | true        | null
-        [allow_scm_jenkinsfile:false] | false | null
-        [allow_scm_jenkinsfile:false, pipeline_template:'dev_template'] | false | 'dev_template'
+        config | expected_allow | expected_template | permissive | reverse_libs
+        [:]   | true        | null   | false | false
+        [allow_scm_jenkinsfile:false, reverse_library_resolution:true] | false | null | false | true
+        [allow_scm_jenkinsfile:false, pipeline_template:'dev_template', permissive_initialization:true] | false | 'dev_template' | true | false
     }
 
 }