# Release Branches

Release branches have a name of `release-MAJOR.MINOR`. Essential Istio repositories are branched from master roughly 4
weeks prior to a new release. The `istio/istio.io` repository does not get branched until the release is ready
for publication.

This document outlines getting in new features after a new branch has been cut and the process for getting a PR
merged in before and after the first public release.

# Feature Freeze

        private
        const val EXPERIMENTAL_BRANCH = "experimental"

        private
        val OLD_RELEASE_PATTERN = "release(\\d+)x".toRegex()

        fun fromDslContext(): VersionedSettingsBranch {
            val branch = DslContext.getParameter("Branch")
            // TeamCity uses a dummy name when first running the DSL
            if (branch.contains("placeholder-1")) {

                        def WORK_DIR=pwd()
                        def ITS_BRANCH = env.CHANGE_BRANCH != null ? env.CHANGE_BRANCH :  env.BRANCH_NAME;
                        try {
                          echo "Checkout ITs from branch: ${ITS_BRANCH}"
                          checkout([$class: 'GitSCM',
                                  branches: [[name: ITS_BRANCH]],

        }

        cleanup {
            history(days = 180)
        }

        this.init()
    }
}

class PublishFinalRelease(branch: VersionedSettingsBranch) : PublishRelease(
    promotedBranch = branch.branchName,
    prepTask = "prepFinalRelease",
    promoteTask = branch.promoteFinalReleaseTaskName(),
    requiredConfirmationCode = "final",
    init = {
        id("Promotion_FinalRelease")

based on a specific branch. Currently, we have two pipelines: `master` and `release`, but you can easily create
and test another isolated pipeline from any branch. 

We'll explain everything via an example. Let's say you make some changes on your branch `myTestBranch`
(we highly recommend to name this branch without prefix and hyphen (`-`) because it's used to generate build type ID) and want to

    buildType(PublishNightlySnapshotFromQuickFeedbackStepPromote(branch))
    buildType(PublishBranchSnapshotFromQuickFeedback)
    buildType(PublishMilestone(branch))

    if (branch.isMaster) {
        buildType(StartReleaseCycle)
        buildType(StartReleaseCycleTest)
    } else {
        buildType(PublishReleaseCandidate(branch))
        buildType(PublishFinalRelease(branch))
    }

    buildDiscarder(logRotator(numToKeepStr: '20', artifactNumToKeepStr: '5'))
    timeout(time: 180, unit: 'MINUTES')
  }
  parameters {
    string( defaultValue: 'master', description: 'Core Its branch (default master)',
            name: 'ITS_BRANCH' )
  }
  stages {
    stage("Build Maven Core") {
      steps {
        withEnv(["JAVA_HOME=${ tool "JDK 1.8 (latest)" }", "PATH+MAVEN=${tool 'Maven 3.6.3'}/bin:${env.JAVA_HOME}/bin"]) {

package promotion

import common.VersionedSettingsBranch
import vcsroots.gradlePromotionBranches

class PublishNightlySnapshotFromQuickFeedbackStepPromote(branch: VersionedSettingsBranch) : BasePublishGradleDistribution(
    promotedBranch = branch.branchName,
    prepTask = branch.prepNightlyTaskName(),
    triggerName = "QuickFeedback",
    vcsRootId = gradlePromotionBranches,
    cleanCheckout = false
) {
    init {

                                def ITS_BRANCH = env.CHANGE_BRANCH != null ? env.CHANGE_BRANCH :  env.BRANCH_NAME;
                                try {
                                  echo "Checkout ITs from branch: ${ITS_BRANCH}"
                                  checkout([$class: 'GitSCM',
                                          branches: [[name: ITS_BRANCH]],

package promotion

import common.VersionedSettingsBranch
import vcsroots.gradlePromotionBranches

class PublishNightlySnapshotFromQuickFeedbackStepUpload(branch: VersionedSettingsBranch) : BasePublishGradleDistribution(
    promotedBranch = branch.branchName,
    prepTask = branch.prepNightlyTaskName(),
    triggerName = "QuickFeedback",
    vcsRootId = gradlePromotionBranches
) {
    init {