接口定义

// Workflow is the definition of a workflow resource
type Workflow struct {
    metav1.TypeMeta   `json:",inline"`
    metav1.ObjectMeta `json:"metadata" protobuf:"bytes,1,opt,name=metadata"`
    Spec              WorkflowSpec   `json:"spec" protobuf:"bytes,2,opt,name=spec "`
    Status            WorkflowStatus `json:"status,omitempty" protobuf:"bytes,3,opt,name=status"`
}

type WorkflowTemplate struct {
    metav1.TypeMeta   `json:",inline"`
    metav1.ObjectMeta `json:"metadata" protobuf:"bytes,1,opt,name=metadata"`
    Spec              WorkflowSpec `json:"spec" protobuf:"bytes,2,opt,name=spec"`
}

type ClusterWorkflowTemplate struct {
    metav1.TypeMeta   `json:",inline"`
    metav1.ObjectMeta `json:"metadata" protobuf:"bytes,1,opt,name=metadata"`
    Spec              WorkflowSpec `json:"spec" protobuf:"bytes,2,opt,name=spec"`
}

// CronWorkflow is the definition of a scheduled workflow resource
type CronWorkflow struct {
    metav1.TypeMeta   `json:",inline"`
    metav1.ObjectMeta `json:"metadata" protobuf:"bytes,1,opt,name=metadata"`
    Spec              CronWorkflowSpec   `json:"spec" protobuf:"bytes,2,opt,name=spec"`
    Status            CronWorkflowStatus `json:"status,omitempty" protobuf:"bytes,3,opt,name=status"`
}

// CronWorkflowSpec is the specification of a CronWorkflow
type CronWorkflowSpec struct {
    // WorkflowSpec is the spec of the workflow to be run
    WorkflowSpec WorkflowSpec `json:"workflowSpec" protobuf:"bytes,1,opt,name=workflowSpec,casttype=WorkflowSpec"`

    // Schedule is a schedule to run the Workflow in Cron format
    // 必填，同 linux cron 语法：https://en.wikipedia.org/wiki/Cron
    Schedule string `json:"schedule" protobuf:"bytes,2,opt,name=schedule"`

    // ConcurrencyPolicy is the K8s-style concurrency policy that will be used
	// 同时存在多个工作流时要执行的策略，可取：Allow Replace Forbid
	// Allow 允许新任务同时执行
	// Replace 移除所有旧任务之后在执行新工作流
	// Forbid 如果旧任务未完成则不允许继续创建
    ConcurrencyPolicy ConcurrencyPolicy `json:"concurrencyPolicy,omitempty" protobuf:"bytes,3,opt,name=concurrencyPolicy,casttype=ConcurrencyPolicy"`

    // Suspend is a flag that will stop new CronWorkflows from running if set to true
    // 设置为 'true' 则停止该工作流调度
    Suspend bool `json:"suspend,omitempty" protobuf:"varint,4,opt,name=suspend"`

    // StartingDeadlineSeconds is the K8s-style deadline that will limit the time a CronWorkflow will be run after its
    // original scheduled time if it is missed.
    // 上次成功运行至当前的最大秒数，如在此期间错过的任务将被执行，比如 "workflow-controller" 故障导致
    StartingDeadlineSeconds *int64 `json:"startingDeadlineSeconds,omitempty" protobuf:"varint,5,opt,name=startingDeadlineSeconds"`

    // SuccessfulJobsHistoryLimit is the number of successful jobs to be kept at a time
	// 对已成功的工作流保留历史数量
    SuccessfulJobsHistoryLimit *int32 `json:"successfulJobsHistoryLimit,omitempty" protobuf:"varint,6,opt,name=successfulJobsHistoryLimit"`

    // FailedJobsHistoryLimit is the number of failed jobs to be kept at a time
	// 对已失败的工作流保留历史数量
    FailedJobsHistoryLimit *int32 `json:"failedJobsHistoryLimit,omitempty" protobuf:"varint,7,opt,name=failedJobsHistoryLimit"`

    // Timezone is the timezone against which the cron schedule will be calculated, e.g. "Asia/Tokyo". Default is machine's local time.
    // 计划任务依赖的时区
    Timezone string `json:"timezone,omitempty" protobuf:"bytes,8,opt,name=timezone"`

    // WorkflowMetadata contains some metadata of the workflow to be run
    WorkflowMetadata *metav1.ObjectMeta `json:"workflowMetadata,omitempty" protobuf:"bytes,9,opt,name=workflowMeta"`
}

type ConcurrencyPolicy string

const (
    AllowConcurrent   ConcurrencyPolicy = "Allow"
    ForbidConcurrent  ConcurrencyPolicy = "Forbid"
    ReplaceConcurrent ConcurrencyPolicy = "Replace"
)

// WorkflowSpec is the specification of a Workflow.
type WorkflowSpec struct {
    // Templates is a list of workflow templates used in a workflow
    // +patchStrategy=merge
    // +patchMergeKey=name
	// 一个工作流由这些子任务组成
    Templates []Template `json:"templates,omitempty" patchStrategy:"merge" patchMergeKey:"name" protobuf:"bytes,1,opt,name=templates"`

    // Entrypoint is a template reference to the starting point of the workflow.
    // 该工作流执行的入口，类似函数的 "main" 功能
    Entrypoint string `json:"entrypoint,omitempty" protobuf:"bytes,2,opt,name=entrypoint"`

    // Arguments contain the parameters and artifacts sent to the workflow entrypoint
    // Parameters are referencable globally using the 'workflow' variable prefix.
    // e.g. {{workflow.parameters.myparam}}
    // 用于配置请求或附件参数，可在下游通过变量 "{{workflow.parameters.myparam}}" 获取
    Arguments Arguments `json:"arguments,omitempty" protobuf:"bytes,3,opt,name=arguments"`

    // ServiceAccountName is the name of the ServiceAccount to run all pods of the workflow as.
	// 流水线 POD 运行的 sa 账户
    ServiceAccountName string `json:"serviceAccountName,omitempty" protobuf:"bytes,4,opt,name=serviceAccountName"`

    // AutomountServiceAccountToken indicates whether a service account token should be automatically mounted in pods.
    // ServiceAccountName of ExecutorConfig must be specified if this value is false.
    // 是否挂载 sa 的 token 至容器内
    AutomountServiceAccountToken *bool `json:"automountServiceAccountToken,omitempty" protobuf:"varint,28,opt,name=automountServiceAccountToken"`

    // Executor holds configurations of executor containers of the workflow.
    // TODO;
    Executor *ExecutorConfig `json:"executor,omitempty" protobuf:"bytes,29,opt,name=executor"`

    // Volumes is a list of volumes that can be mounted by containers in a workflow.
    // +patchStrategy=merge
    // +patchMergeKey=name
	// 挂载至工作流任务中 POD 的卷，见[Pod Volume](/docs/concepts/workloads/pods-volume/)
    Volumes []apiv1.Volume `json:"volumes,omitempty" patchStrategy:"merge" patchMergeKey:"name" protobuf:"bytes,5,opt,name=volumes"`

    // VolumeClaimTemplates is a list of claims that containers are allowed to reference.
    // The Workflow controller will create the claims at the beginning of the workflow
    // and delete the claims upon completion of the workflow
    VolumeClaimTemplates []apiv1.PersistentVolumeClaim `json:"volumeClaimTemplates,omitempty" protobuf:"bytes,6,opt,name=volumeClaimTemplates"`

    // Parallelism limits the max total parallel pods that can execute at the same time in a workflow
	// 同一时间内最大可并行执行的任务数量
    Parallelism *int64 `json:"parallelism,omitempty" protobuf:"bytes,7,opt,name=parallelism"`

    // ArtifactRepositoryRef specifies the configMap name and key containing the artifact repository config.
    ArtifactRepositoryRef *ArtifactRepositoryRef `json:"artifactRepositoryRef,omitempty" protobuf:"bytes,8,opt,name=artifactRepositoryRef"`

    // Suspend will suspend the workflow and prevent execution of any future steps in the workflow
	// 挂起工作流
    Suspend *bool `json:"suspend,omitempty" protobuf:"bytes,9,opt,name=suspend"`

    // NodeSelector is a selector which will result in all pods of the workflow
    // to be scheduled on the selected node(s). This is able to be overridden by
    // a nodeSelector specified in the template.
	// 调度任务至关联的主机节点
    NodeSelector map[string]string `json:"nodeSelector,omitempty" protobuf:"bytes,10,opt,name=nodeSelector"`

    // Affinity sets the scheduling constraints for all pods in the workflow.
    // Can be overridden by an affinity specified in the template
    // 亲和性配置，见 [Pod Affinity](/docs/concepts/workloads/pods-affinity/)
    Affinity *apiv1.Affinity `json:"affinity,omitempty" protobuf:"bytes,11,opt,name=affinity"`

    // Tolerations to apply to workflow pods.
    // +patchStrategy=merge
    // +patchMergeKey=key
	// 污点，见 [Toleration](/docs/concepts/workloads/pods/#toleration)
    Tolerations []apiv1.Toleration `json:"tolerations,omitempty" patchStrategy:"merge" patchMergeKey:"key" protobuf:"bytes,12,opt,name=tolerations"`

    // ImagePullSecrets is a list of references to secrets in the same namespace to use for pulling any images
    // in pods that reference this ServiceAccount. ImagePullSecrets are distinct from Secrets because Secrets
    // can be mounted in the pod, but ImagePullSecrets are only accessed by the kubelet.
    // More info: https://kubernetes.io/docs/concepts/containers/images/#specifying-imagepullsecrets-on-a-pod
    // +patchStrategy=merge
    // +patchMergeKey=name
	// 拉取镜像的密钥文件
    ImagePullSecrets []apiv1.LocalObjectReference `json:"imagePullSecrets,omitempty" patchStrategy:"merge" patchMergeKey:"name" protobuf:"bytes,13,opt,name=imagePullSecrets"`

    // Host networking requested for this workflow pod. Default to false.
    // 工作流使用主机网络
    HostNetwork *bool `json:"hostNetwork,omitempty" protobuf:"bytes,14,opt,name=hostNetwork"`

    // Set DNS policy for workflow pods.
    // Defaults to "ClusterFirst".
    // Valid values are 'ClusterFirstWithHostNet', 'ClusterFirst', 'Default' or 'None'.
    // DNS parameters given in DNSConfig will be merged with the policy selected with DNSPolicy.
    // To have DNS options set along with hostNetwork, you have to specify DNS policy
    // explicitly to 'ClusterFirstWithHostNet'.
    // 工作流 pod 使用的 dns 策略，见[PodDNSConfig](/docs/concepts/workloads/pods/#poddnsconfig)
    DNSPolicy *apiv1.DNSPolicy `json:"dnsPolicy,omitempty" protobuf:"bytes,15,opt,name=dnsPolicy"`

    // PodDNSConfig defines the DNS parameters of a pod in addition to
    // those generated from DNSPolicy.
    // 工作流 pod 使用的 dns 策略，见[PodDNSConfig](/docs/concepts/workloads/pods/#poddnsconfig)
    DNSConfig *apiv1.PodDNSConfig `json:"dnsConfig,omitempty" protobuf:"bytes,16,opt,name=dnsConfig"`

    // OnExit is a template reference which is invoked at the end of the
    // workflow, irrespective of the success, failure, or error of the
    // primary workflow.
    // 在工作流结束时调用，无论是否执行成功或失败、错误，一般用于消息推送
    OnExit string `json:"onExit,omitempty" protobuf:"bytes,17,opt,name=onExit"`

    // TTLStrategy limits the lifetime of a Workflow that has finished execution depending on if it
    // Succeeded or Failed. If this struct is set, once the Workflow finishes, it will be
    // deleted after the time to live expires. If this field is unset,
    // the controller config map will hold the default values.
	// 工作流生命周期
    TTLStrategy *TTLStrategy `json:"ttlStrategy,omitempty" protobuf:"bytes,30,opt,name=ttlStrategy"`

    // Optional duration in seconds relative to the workflow start time which the workflow is
    // allowed to run before the controller terminates the workflow. A value of zero is used to
    // terminate a Running workflow
    // 允许工作流最长执行时间，默认没有时间限制
    ActiveDeadlineSeconds *int64 `json:"activeDeadlineSeconds,omitempty" protobuf:"bytes,19,opt,name=activeDeadlineSeconds"`

    // Priority is used if controller is configured to process limited number of workflows in parallel. Workflows with higher priority are processed first.
    // 并行处理有限数量的工作流程中，优先级越高越先执行
    Priority *int32 `json:"priority,omitempty" protobuf:"bytes,20,opt,name=priority"`

    // Set scheduler name for all pods.
    // Will be overridden if container/script template's scheduler name is set.
    // Default scheduler will be used if neither specified.
    // +optional
    // 使用 k8s 集群调度程序名称
    SchedulerName string `json:"schedulerName,omitempty" protobuf:"bytes,21,opt,name=schedulerName"`

    // PodGC describes the strategy to use when deleting completed pods
    // 任务完成后 pod 是否删除策略
    PodGC *PodGC `json:"podGC,omitempty" protobuf:"bytes,22,opt,name=podGC"`

    // PriorityClassName to apply to workflow pods.
	// TODO;
    PodPriorityClassName string `json:"podPriorityClassName,omitempty" protobuf:"bytes,23,opt,name=podPriorityClassName"`

    // Priority to apply to workflow pods.
    // DEPRECATED: Use PodPriorityClassName instead.
    PodPriority *int32 `json:"podPriority,omitempty" protobuf:"bytes,24,opt,name=podPriority"`

    // +patchStrategy=merge
    // +patchMergeKey=ip
    // 见 [PodSpec](/docs/concepts/workloads/pods/#podspec)
    HostAliases []apiv1.HostAlias `json:"hostAliases,omitempty" patchStrategy:"merge" patchMergeKey:"ip" protobuf:"bytes,25,opt,name=hostAliases"`

    // SecurityContext holds pod-level security attributes and common container settings.
    // Optional: Defaults to empty.  See type description for default values of each field.
    // +optional
	// 容器安全上下文，见 [Pod Security](/docs/concepts/workloads/pods-security/)
    SecurityContext *apiv1.PodSecurityContext `json:"securityContext,omitempty" protobuf:"bytes,26,opt,name=securityContext"`

    // PodSpecPatch holds strategic merge patch to apply against the pod spec. Allows parameterization of
    // container fields which are not strings (e.g. resource limits).
    PodSpecPatch string `json:"podSpecPatch,omitempty" protobuf:"bytes,27,opt,name=podSpecPatch"`

    // PodDisruptionBudget holds the number of concurrent disruptions that you allow for Workflow's Pods.
    // Controller will automatically add the selector with workflow name, if selector is empty.
    // Optional: Defaults to empty.
    // +optional
    PodDisruptionBudget *policyv1.PodDisruptionBudgetSpec `json:"podDisruptionBudget,omitempty" protobuf:"bytes,31,opt,name=podDisruptionBudget"`

    // Metrics are a list of metrics emitted from this Workflow
    // 该工作流关联的指标
    Metrics *Metrics `json:"metrics,omitempty" protobuf:"bytes,32,opt,name=metrics"`

    // Shutdown will shutdown the workflow according to its ShutdownStrategy
	// TODO；关闭的策略
    Shutdown ShutdownStrategy `json:"shutdown,omitempty" protobuf:"bytes,33,opt,name=shutdown,casttype=ShutdownStrategy"`

    // WorkflowTemplateRef holds a reference to a WorkflowTemplate for execution
	// TODO;
    WorkflowTemplateRef *WorkflowTemplateRef `json:"workflowTemplateRef,omitempty" protobuf:"bytes,34,opt,name=workflowTemplateRef"`

    // Synchronization holds synchronization lock configuration for this Workflow
	// 工作流的同步锁配置
    Synchronization *Synchronization `json:"synchronization,omitempty" protobuf:"bytes,35,opt,name=synchronization,casttype=Synchronization"`

    // VolumeClaimGC describes the strategy to use when deleting volumes from completed workflows
	// 工作流程删除卷策略
    VolumeClaimGC *VolumeClaimGC `json:"volumeClaimGC,omitempty" protobuf:"bytes,36,opt,name=volumeClaimGC,casttype=VolumeClaimGC"`

    // RetryStrategy for all templates in the workflow.
	// 重试策略
    RetryStrategy *RetryStrategy `json:"retryStrategy,omitempty" protobuf:"bytes,37,opt,name=retryStrategy"`

    // PodMetadata defines additional metadata that should be applied to workflow pods
    // 植入额外的 labels 与 annotations 至工作流关联 POD
    PodMetadata *Metadata `json:"podMetadata,omitempty" protobuf:"bytes,38,opt,name=podMetadata"`

    // TemplateDefaults holds default template values that will apply to all templates in the Workflow, unless overridden on the template-level
	// 各项子任务的默认值
    TemplateDefaults *Template `json:"templateDefaults,omitempty" protobuf:"bytes,39,opt,name=templateDefaults"`

    // ArchiveLogs indicates if the container logs should be archived
    // 容器运行日志是否被归档保存
    ArchiveLogs *bool `json:"archiveLogs,omitempty" protobuf:"varint,40,opt,name=archiveLogs"`

    // Hooks holds the lifecycle hook which is invoked at lifecycle of
    // step, irrespective of the success, failure, or error status of the primary step
	// TODO;
    Hooks LifecycleHooks `json:"hooks,omitempty" protobuf:"bytes,41,opt,name=hooks"`

    // WorkflowMetadata contains some metadata of the workflow to refer to
	// 关联工作流的元数据
    WorkflowMetadata *WorkflowMetadata `json:"workflowMetadata,omitempty" protobuf:"bytes,42,opt,name=workflowMetadata"`

    // ArtifactGC describes the strategy to use when deleting artifacts from completed or deleted workflows (applies to all output Artifacts
    // unless Artifact.ArtifactGC is specified, which overrides this)
    // 删除工作流之后，附件的保留策略
    ArtifactGC *ArtifactGC `json:"artifactGC,omitempty" protobuf:"bytes,43,opt,name=artifactGC"`
}

// Template is a reusable and composable unit of execution in a workflow
type Template struct {
    // Name is the name of the template
    Name string `json:"name,omitempty" protobuf:"bytes,1,opt,name=name"`

    // Inputs describe what inputs parameters and artifacts are supplied to this template
    Inputs Inputs `json:"inputs,omitempty" protobuf:"bytes,5,opt,name=inputs"`

    // Outputs describe the parameters and artifacts that this template produces
    Outputs Outputs `json:"outputs,omitempty" protobuf:"bytes,6,opt,name=outputs"`

    // NodeSelector is a selector to schedule this step of the workflow to be
    // run on the selected node(s). Overrides the selector set at the workflow level.
    NodeSelector map[string]string `json:"nodeSelector,omitempty" protobuf:"bytes,7,opt,name=nodeSelector"`

    // Affinity sets the pod's scheduling constraints
    // Overrides the affinity set at the workflow level (if any)
    Affinity *apiv1.Affinity `json:"affinity,omitempty" protobuf:"bytes,8,opt,name=affinity"`

    // Metdata sets the pods's metadata, i.e. annotations and labels
    Metadata Metadata `json:"metadata,omitempty" protobuf:"bytes,9,opt,name=metadata"`

    // Daemon will allow a workflow to proceed to the next step so long as the container reaches readiness
    Daemon *bool `json:"daemon,omitempty" protobuf:"bytes,10,opt,name=daemon"`

    // Steps define a series of sequential/parallel workflow steps
    Steps []ParallelSteps `json:"steps,omitempty" protobuf:"bytes,11,opt,name=steps"`

    // Container is the main container image to run in the pod
    Container *apiv1.Container `json:"container,omitempty" protobuf:"bytes,12,opt,name=container"`

    // ContainerSet groups multiple containers within a single pod.
    ContainerSet *ContainerSetTemplate `json:"containerSet,omitempty" protobuf:"bytes,40,opt,name=containerSet"`

    // Script runs a portion of code against an interpreter
    Script *ScriptTemplate `json:"script,omitempty" protobuf:"bytes,13,opt,name=script"`

    // Resource template subtype which can run k8s resources
    Resource *ResourceTemplate `json:"resource,omitempty" protobuf:"bytes,14,opt,name=resource"`

    // DAG template subtype which runs a DAG
    DAG *DAGTemplate `json:"dag,omitempty" protobuf:"bytes,15,opt,name=dag"`

    // Suspend template subtype which can suspend a workflow when reaching the step
    Suspend *SuspendTemplate `json:"suspend,omitempty" protobuf:"bytes,16,opt,name=suspend"`

    // Data is a data template
    Data *Data `json:"data,omitempty" protobuf:"bytes,39,opt,name=data"`

    // HTTP makes a HTTP request
    HTTP *HTTP `json:"http,omitempty" protobuf:"bytes,42,opt,name=http"`

    // Plugin is a plugin template
    Plugin *Plugin `json:"plugin,omitempty" protobuf:"bytes,43,opt,name=plugin"`

    // Volumes is a list of volumes that can be mounted by containers in a template.
    // +patchStrategy=merge
    // +patchMergeKey=name
    Volumes []apiv1.Volume `json:"volumes,omitempty" patchStrategy:"merge" patchMergeKey:"name" protobuf:"bytes,17,opt,name=volumes"`

    // InitContainers is a list of containers which run before the main container.
    // +patchStrategy=merge
    // +patchMergeKey=name
    InitContainers []UserContainer `json:"initContainers,omitempty" patchStrategy:"merge" patchMergeKey:"name" protobuf:"bytes,18,opt,name=initContainers"`

    // Sidecars is a list of containers which run alongside the main container
    // Sidecars are automatically killed when the main container completes
    // +patchStrategy=merge
    // +patchMergeKey=name
    Sidecars []UserContainer `json:"sidecars,omitempty" patchStrategy:"merge" patchMergeKey:"name" protobuf:"bytes,19,opt,name=sidecars"`

    // Location in which all files related to the step will be stored (logs, artifacts, etc...).
    // Can be overridden by individual items in Outputs. If omitted, will use the default
    // artifact repository location configured in the controller, appended with the
    // <workflowname>/<nodename> in the key.
    ArchiveLocation *ArtifactLocation `json:"archiveLocation,omitempty" protobuf:"bytes,20,opt,name=archiveLocation"`

    // Optional duration in seconds relative to the StartTime that the pod may be active on a node
    // before the system actively tries to terminate the pod; value must be positive integer
    // This field is only applicable to container and script templates.
    ActiveDeadlineSeconds *intstr.IntOrString `json:"activeDeadlineSeconds,omitempty" protobuf:"bytes,21,opt,name=activeDeadlineSeconds"`

    // RetryStrategy describes how to retry a template when it fails
    RetryStrategy *RetryStrategy `json:"retryStrategy,omitempty" protobuf:"bytes,22,opt,name=retryStrategy"`

    // Parallelism limits the max total parallel pods that can execute at the same time within the
    // boundaries of this template invocation. If additional steps/dag templates are invoked, the
    // pods created by those templates will not be counted towards this total.
    Parallelism *int64 `json:"parallelism,omitempty" protobuf:"bytes,23,opt,name=parallelism"`

    // FailFast, if specified, will fail this template if any of its child pods has failed. This is useful for when this
    // template is expanded with `withItems`, etc.
    FailFast *bool `json:"failFast,omitempty" protobuf:"varint,41,opt,name=failFast"`

    // Tolerations to apply to workflow pods.
    // +patchStrategy=merge
    // +patchMergeKey=key
    Tolerations []apiv1.Toleration `json:"tolerations,omitempty" patchStrategy:"merge" patchMergeKey:"key" protobuf:"bytes,24,opt,name=tolerations"`

    // If specified, the pod will be dispatched by specified scheduler.
    // Or it will be dispatched by workflow scope scheduler if specified.
    // If neither specified, the pod will be dispatched by default scheduler.
    // +optional
    SchedulerName string `json:"schedulerName,omitempty" protobuf:"bytes,25,opt,name=schedulerName"`

    // PriorityClassName to apply to workflow pods.
    PriorityClassName string `json:"priorityClassName,omitempty" protobuf:"bytes,26,opt,name=priorityClassName"`

    // Priority to apply to workflow pods.
    Priority *int32 `json:"priority,omitempty" protobuf:"bytes,27,opt,name=priority"`

    // ServiceAccountName to apply to workflow pods
    ServiceAccountName string `json:"serviceAccountName,omitempty" protobuf:"bytes,28,opt,name=serviceAccountName"`

    // AutomountServiceAccountToken indicates whether a service account token should be automatically mounted in pods.
    // ServiceAccountName of ExecutorConfig must be specified if this value is false.
    AutomountServiceAccountToken *bool `json:"automountServiceAccountToken,omitempty" protobuf:"varint,32,opt,name=automountServiceAccountToken"`

    // Executor holds configurations of the executor container.
    Executor *ExecutorConfig `json:"executor,omitempty" protobuf:"bytes,33,opt,name=executor"`

    // HostAliases is an optional list of hosts and IPs that will be injected into the pod spec
    // +patchStrategy=merge
    // +patchMergeKey=ip
    HostAliases []apiv1.HostAlias `json:"hostAliases,omitempty" patchStrategy:"merge" patchMergeKey:"ip" protobuf:"bytes,29,opt,name=hostAliases"`

    // SecurityContext holds pod-level security attributes and common container settings.
    // Optional: Defaults to empty.  See type description for default values of each field.
    // +optional
    SecurityContext *apiv1.PodSecurityContext `json:"securityContext,omitempty" protobuf:"bytes,30,opt,name=securityContext"`

    // PodSpecPatch holds strategic merge patch to apply against the pod spec. Allows parameterization of
    // container fields which are not strings (e.g. resource limits).
    PodSpecPatch string `json:"podSpecPatch,omitempty" protobuf:"bytes,31,opt,name=podSpecPatch"`

    // Metrics are a list of metrics emitted from this template
    Metrics *Metrics `json:"metrics,omitempty" protobuf:"bytes,35,opt,name=metrics"`

    // Synchronization holds synchronization lock configuration for this template
    Synchronization *Synchronization `json:"synchronization,omitempty" protobuf:"bytes,36,opt,name=synchronization,casttype=Synchronization"`

    // Memoize allows templates to use outputs generated from already executed templates
    Memoize *Memoize `json:"memoize,omitempty" protobuf:"bytes,37,opt,name=memoize"`

    // Timeout allows to set the total node execution timeout duration counting from the node's start time.
    // This duration also includes time in which the node spends in Pending state. This duration may not be applied to Step or DAG templates.
    Timeout string `json:"timeout,omitempty" protobuf:"bytes,38,opt,name=timeout"`
}

// Inputs are the mechanism for passing parameters, artifacts, volumes from one template to another
type Inputs struct {
    // Parameters are a list of parameters passed as inputs
    // +patchStrategy=merge
    // +patchMergeKey=name
    Parameters []Parameter `json:"parameters,omitempty" patchStrategy:"merge" patchMergeKey:"name" protobuf:"bytes,1,opt,name=parameters"`

    // Artifact are a list of artifacts passed as inputs
    // +patchStrategy=merge
    // +patchMergeKey=name
    Artifacts Artifacts `json:"artifacts,omitempty" patchStrategy:"merge" patchMergeKey:"name" protobuf:"bytes,2,opt,name=artifacts"`
}

// Outputs hold parameters, artifacts, and results from a step
type Outputs struct {
    // Parameters holds the list of output parameters produced by a step
    // +patchStrategy=merge
    // +patchMergeKey=name
    Parameters []Parameter `json:"parameters,omitempty" patchStrategy:"merge" patchMergeKey:"name" protobuf:"bytes,1,rep,name=parameters"`

    // Artifacts holds the list of output artifacts produced by a step
    // +patchStrategy=merge
    // +patchMergeKey=name
    Artifacts Artifacts `json:"artifacts,omitempty" patchStrategy:"merge" patchMergeKey:"name" protobuf:"bytes,2,rep,name=artifacts"`

    // Result holds the result (stdout) of a script template
    Result *string `json:"result,omitempty" protobuf:"bytes,3,opt,name=result"`

    // ExitCode holds the exit code of a script template
    ExitCode *string `json:"exitCode,omitempty" protobuf:"bytes,4,opt,name=exitCode"`
}

// Pod metdata
type Metadata struct {
    Annotations map[string]string `json:"annotations,omitempty" protobuf:"bytes,1,opt,name=annotations"`
    Labels      map[string]string `json:"labels,omitempty" protobuf:"bytes,2,opt,name=labels"`
}

// +kubebuilder:validation:Type=array
type ParallelSteps struct {
    Steps []WorkflowStep `json:"-" protobuf:"bytes,1,rep,name=steps"`
}

type ContainerSetTemplate struct {
    Containers   []ContainerNode      `json:"containers" protobuf:"bytes,4,rep,name=containers"`
    VolumeMounts []corev1.VolumeMount `json:"volumeMounts,omitempty" protobuf:"bytes,3,rep,name=volumeMounts"`
    // RetryStrategy describes how to retry a container nodes in the container set if it fails.
    // Nbr of retries(default 0) and sleep duration between retries(default 0s, instant retry) can be set.
    RetryStrategy *ContainerSetRetryStrategy `json:"retryStrategy,omitempty" protobuf:"bytes,5,opt,name=retryStrategy"`
}

// ScriptTemplate is a template subtype to enable scripting through code steps
type ScriptTemplate struct {
    apiv1.Container `json:",inline" protobuf:"bytes,1,opt,name=container"`

    // Source contains the source code of the script to execute
    Source string `json:"source" protobuf:"bytes,2,opt,name=source"`
}

// ResourceTemplate is a template subtype to manipulate kubernetes resources
type ResourceTemplate struct {
    // Action is the action to perform to the resource.
    // Must be one of: get, create, apply, delete, replace, patch
    Action string `json:"action" protobuf:"bytes,1,opt,name=action"`

    // MergeStrategy is the strategy used to merge a patch. It defaults to "strategic"
    // Must be one of: strategic, merge, json
    MergeStrategy string `json:"mergeStrategy,omitempty" protobuf:"bytes,2,opt,name=mergeStrategy"`

    // Manifest contains the kubernetes manifest
    Manifest string `json:"manifest,omitempty" protobuf:"bytes,3,opt,name=manifest"`

    // ManifestFrom is the source for a single kubernetes manifest
    ManifestFrom *ManifestFrom `json:"manifestFrom,omitempty" protobuf:"bytes,8,opt,name=manifestFrom"`

    // SetOwnerReference sets the reference to the workflow on the OwnerReference of generated resource.
    SetOwnerReference bool `json:"setOwnerReference,omitempty" protobuf:"varint,4,opt,name=setOwnerReference"`

    // SuccessCondition is a label selector expression which describes the conditions
    // of the k8s resource in which it is acceptable to proceed to the following step
    SuccessCondition string `json:"successCondition,omitempty" protobuf:"bytes,5,opt,name=successCondition"`

    // FailureCondition is a label selector expression which describes the conditions
    // of the k8s resource in which the step was considered failed
    FailureCondition string `json:"failureCondition,omitempty" protobuf:"bytes,6,opt,name=failureCondition"`

    // Flags is a set of additional options passed to kubectl before submitting a resource
    // I.e. to disable resource validation:
    // flags: [
    //  "--validate=false"  # disable resource validation
    // ]
    Flags []string `json:"flags,omitempty" protobuf:"varint,7,opt,name=flags"`
}

// DAGTemplate is a template subtype for directed acyclic graph templates
type DAGTemplate struct {
    // Target are one or more names of targets to execute in a DAG
    Target string `json:"target,omitempty" protobuf:"bytes,1,opt,name=target"`

    // Tasks are a list of DAG tasks
    // +patchStrategy=merge
    // +patchMergeKey=name
    Tasks []DAGTask `json:"tasks" patchStrategy:"merge" patchMergeKey:"name" protobuf:"bytes,2,rep,name=tasks"`

    // This flag is for DAG logic. The DAG logic has a built-in "fail fast" feature to stop scheduling new steps,
    // as soon as it detects that one of the DAG nodes is failed. Then it waits until all DAG nodes are completed
    // before failing the DAG itself.
    // The FailFast flag default is true,  if set to false, it will allow a DAG to run all branches of the DAG to
    // completion (either success or failure), regardless of the failed outcomes of branches in the DAG.
    // More info and example about this feature at https://github.com/argoproj/argo-workflows/issues/1442
    FailFast *bool `json:"failFast,omitempty" protobuf:"varint,3,opt,name=failFast"`
}

// DAGTask represents a node in the graph during DAG execution
type DAGTask struct {
    // Name is the name of the target
    Name string `json:"name" protobuf:"bytes,1,opt,name=name"`

    // Name of template to execute
    Template string `json:"template,omitempty" protobuf:"bytes,2,opt,name=template"`

    // Inline is the template. Template must be empty if this is declared (and vice-versa).
    Inline *Template `json:"inline,omitempty" protobuf:"bytes,14,opt,name=inline"`

    // Arguments are the parameter and artifact arguments to the template
    Arguments Arguments `json:"arguments,omitempty" protobuf:"bytes,3,opt,name=arguments"`

    // TemplateRef is the reference to the template resource to execute.
    TemplateRef *TemplateRef `json:"templateRef,omitempty" protobuf:"bytes,4,opt,name=templateRef"`

    // Dependencies are name of other targets which this depends on
    Dependencies []string `json:"dependencies,omitempty" protobuf:"bytes,5,rep,name=dependencies"`

    // WithItems expands a task into multiple parallel tasks from the items in the list
    WithItems []Item `json:"withItems,omitempty" protobuf:"bytes,6,rep,name=withItems"`

    // WithParam expands a task into multiple parallel tasks from the value in the parameter,
    // which is expected to be a JSON list.
    WithParam string `json:"withParam,omitempty" protobuf:"bytes,7,opt,name=withParam"`

    // WithSequence expands a task into a numeric sequence
    WithSequence *Sequence `json:"withSequence,omitempty" protobuf:"bytes,8,opt,name=withSequence"`

    // When is an expression in which the task should conditionally execute
    When string `json:"when,omitempty" protobuf:"bytes,9,opt,name=when"`

    // ContinueOn makes argo to proceed with the following step even if this step fails.
    // Errors and Failed states can be specified
    ContinueOn *ContinueOn `json:"continueOn,omitempty" protobuf:"bytes,10,opt,name=continueOn"`

    // OnExit is a template reference which is invoked at the end of the
    // template, irrespective of the success, failure, or error of the
    // primary template.
    // DEPRECATED: Use Hooks[exit].Template instead.
    OnExit string `json:"onExit,omitempty" protobuf:"bytes,11,opt,name=onExit"`

    // Depends are name of other targets which this depends on
    Depends string `json:"depends,omitempty" protobuf:"bytes,12,opt,name=depends"`

    // Hooks hold the lifecycle hook which is invoked at lifecycle of
    // task, irrespective of the success, failure, or error status of the primary task
    Hooks LifecycleHooks `json:"hooks,omitempty" protobuf:"bytes,13,opt,name=hooks"`
}

// SuspendTemplate is a template subtype to suspend a workflow at a predetermined point in time
type SuspendTemplate struct {
    // Duration is the seconds to wait before automatically resuming a template. Must be a string. Default unit is seconds.
    // Could also be a Duration, e.g.: "2m", "6h", "1d"
    Duration string `json:"duration,omitempty" protobuf:"bytes,1,opt,name=duration"`
}

// Data is a data template
type Data struct {
    // Source sources external data into a data template
    Source DataSource `json:"source" protobuf:"bytes,1,opt,name=source"`

    // Transformation applies a set of transformations
    Transformation Transformation `json:"transformation" protobuf:"bytes,2,rep,name=transformation"`
}

type Transformation []TransformationStep

type TransformationStep struct {
    // Expression defines an expr expression to apply
    Expression string `json:"expression" protobuf:"bytes,1,opt,name=expression"`
}

// DataSource sources external data into a data template
type DataSource struct {
    // ArtifactPaths is a data transformation that collects a list of artifact paths
    ArtifactPaths *ArtifactPaths `json:"artifactPaths,omitempty" protobuf:"bytes,1,opt,name=artifactPaths"`
}

// ArtifactPaths expands a step from a collection of artifacts
type ArtifactPaths struct {
    // Artifact is the artifact location from which to source the artifacts, it can be a directory
    Artifact `json:",inline" protobuf:"bytes,1,opt,name=artifact"`
}

type HTTP struct {
    // Method is HTTP methods for HTTP Request
    Method string `json:"method,omitempty" protobuf:"bytes,1,opt,name=method"`
    // URL of the HTTP Request
    URL string `json:"url" protobuf:"bytes,2,opt,name=url"`
    // Headers are an optional list of headers to send with HTTP requests
    Headers HTTPHeaders `json:"headers,omitempty" protobuf:"bytes,3,rep,name=headers"`
    // TimeoutSeconds is request timeout for HTTP Request. Default is 30 seconds
    TimeoutSeconds *int64 `json:"timeoutSeconds,omitempty" protobuf:"bytes,4,opt,name=timeoutSeconds"`
    // SuccessCondition is an expression if evaluated to true is considered successful
    SuccessCondition string `json:"successCondition,omitempty" protobuf:"bytes,6,opt,name=successCondition"`
    // Body is content of the HTTP Request
    Body string `json:"body,omitempty" protobuf:"bytes,5,opt,name=body"`
    // BodyFrom is  content of the HTTP Request as Bytes
    BodyFrom *HTTPBodySource `json:"bodyFrom,omitempty" protobuf:"bytes,8,opt,name=bodyFrom"`
    // InsecureSkipVerify is a bool when if set to true will skip TLS verification for the HTTP client
    InsecureSkipVerify bool `json:"insecureSkipVerify,omitempty" protobuf:"bytes,7,opt,name=insecureSkipVerify"`
}

type HTTPHeader struct {
    Name      string            `json:"name" protobuf:"bytes,1,opt,name=name"`
    Value     string            `json:"value,omitempty" protobuf:"bytes,2,opt,name=value"`
    ValueFrom *HTTPHeaderSource `json:"valueFrom,omitempty" protobuf:"bytes,3,opt,name=valueFrom"`
}

type HTTPHeaderSource struct {
    SecretKeyRef *v1.SecretKeySelector `json:"secretKeyRef,omitempty" protobuf:"bytes,1,opt,name=secretKeyRef"`
}

type HTTPHeaders []HTTPHeader

// HTTPBodySource contains the source of the HTTP body.
type HTTPBodySource struct {
    Bytes []byte `json:"bytes,omitempty" protobuf:"bytes,1,opt,name=bytes"`
}

// Plugin is an Object with exactly one key
type Plugin struct {
    Object `json:",inline" protobuf:"bytes,1,opt,name=object"`
}

// UserContainer is a container specified by a user.
type UserContainer struct {
    apiv1.Container `json:",inline" protobuf:"bytes,1,opt,name=container"`

    // MirrorVolumeMounts will mount the same volumes specified in the main container
    // to the container (including artifacts), at the same mountPaths. This enables
    // dind daemon to partially see the same filesystem as the main container in
    // order to use features such as docker volume binding
    MirrorVolumeMounts *bool `json:"mirrorVolumeMounts,omitempty" protobuf:"varint,2,opt,name=mirrorVolumeMounts"`
}

// ArtifactLocation describes a location for a single or multiple artifacts.
// It is used as single artifact in the context of inputs/outputs (e.g. outputs.artifacts.artname).
// It is also used to describe the location of multiple artifacts such as the archive location
// of a single workflow step, which the executor will use as a default location to store its files.
type ArtifactLocation struct {
    // ArchiveLogs indicates if the container logs should be archived
    ArchiveLogs *bool `json:"archiveLogs,omitempty" protobuf:"varint,1,opt,name=archiveLogs"`

    // S3 contains S3 artifact location details
    S3 *S3Artifact `json:"s3,omitempty" protobuf:"bytes,2,opt,name=s3"`

    // Git contains git artifact location details
    Git *GitArtifact `json:"git,omitempty" protobuf:"bytes,3,opt,name=git"`

    // HTTP contains HTTP artifact location details
    HTTP *HTTPArtifact `json:"http,omitempty" protobuf:"bytes,4,opt,name=http"`

    // Artifactory contains artifactory artifact location details
    Artifactory *ArtifactoryArtifact `json:"artifactory,omitempty" protobuf:"bytes,5,opt,name=artifactory"`

    // HDFS contains HDFS artifact location details
    HDFS *HDFSArtifact `json:"hdfs,omitempty" protobuf:"bytes,6,opt,name=hdfs"`

    // Raw contains raw artifact location details
    Raw *RawArtifact `json:"raw,omitempty" protobuf:"bytes,7,opt,name=raw"`

    // OSS contains OSS artifact location details
    OSS *OSSArtifact `json:"oss,omitempty" protobuf:"bytes,8,opt,name=oss"`

    // GCS contains GCS artifact location details
    GCS *GCSArtifact `json:"gcs,omitempty" protobuf:"bytes,9,opt,name=gcs"`

    // Azure contains Azure Storage artifact location details
    Azure *AzureArtifact `json:"azure,omitempty" protobuf:"bytes,10,opt,name=azure"`
}

// RetryStrategy provides controls on how to retry a workflow step
type RetryStrategy struct {
    // Limit is the maximum number of retry attempts when retrying a container. It does not include the original
    // container; the maximum number of total attempts will be `limit + 1`.
    Limit *intstr.IntOrString `json:"limit,omitempty" protobuf:"varint,1,opt,name=limit"`

    // RetryPolicy is a policy of NodePhase statuses that will be retried
    RetryPolicy RetryPolicy `json:"retryPolicy,omitempty" protobuf:"bytes,2,opt,name=retryPolicy,casttype=RetryPolicy"`

    // Backoff is a backoff strategy
    Backoff *Backoff `json:"backoff,omitempty" protobuf:"bytes,3,opt,name=backoff,casttype=Backoff"`

    // Affinity prevents running workflow's step on the same host
    Affinity *RetryAffinity `json:"affinity,omitempty" protobuf:"bytes,4,opt,name=affinity"`

    // Expression is a condition expression for when a node will be retried. If it evaluates to false, the node will not
    // be retried and the retry strategy will be ignored
    Expression string `json:"expression,omitempty" protobuf:"bytes,5,opt,name=expression"`
}

// ExecutorConfig holds configurations of an executor container.
type ExecutorConfig struct {
    // ServiceAccountName specifies the service account name of the executor container.
    ServiceAccountName string `json:"serviceAccountName,omitempty" protobuf:"bytes,1,opt,name=serviceAccountName"`
}

const (
    MetricTypeGauge     MetricType = "Gauge"
    MetricTypeHistogram MetricType = "Histogram"
    MetricTypeCounter   MetricType = "Counter"
    MetricTypeUnknown   MetricType = "Unknown"
)

// Metrics are a list of metrics emitted from a Workflow/Template
type Metrics struct {
    // Prometheus is a list of prometheus metrics to be emitted
    Prometheus []*Prometheus `json:"prometheus" protobuf:"bytes,1,rep,name=prometheus"`
}

// Prometheus is a prometheus metric to be emitted
type Prometheus struct {
    // Name is the name of the metric
    Name string `json:"name" protobuf:"bytes,1,opt,name=name"`
    // Labels is a list of metric labels
    Labels []*MetricLabel `json:"labels,omitempty" protobuf:"bytes,2,rep,name=labels"`
    // Help is a string that describes the metric
    Help string `json:"help" protobuf:"bytes,3,opt,name=help"`
    // When is a conditional statement that decides when to emit the metric
    When string `json:"when,omitempty" protobuf:"bytes,4,opt,name=when"`
    // Gauge is a gauge metric
    Gauge *Gauge `json:"gauge,omitempty" protobuf:"bytes,5,opt,name=gauge"`
    // Histogram is a histogram metric
    Histogram *Histogram `json:"histogram,omitempty" protobuf:"bytes,6,opt,name=histogram"`
    // Counter is a counter metric
    Counter *Counter `json:"counter,omitempty" protobuf:"bytes,7,opt,name=counter"`
}

// SynchronizationStatus stores the status of semaphore and mutex.
type SynchronizationStatus struct {
    // Semaphore stores this workflow's Semaphore holder details
    Semaphore *SemaphoreStatus `json:"semaphore,omitempty" protobuf:"bytes,1,opt,name=semaphore"`
    // Mutex stores this workflow's mutex holder details
    Mutex *MutexStatus `json:"mutex,omitempty" protobuf:"bytes,2,opt,name=mutex"`
}

// Memoization enables caching for the Outputs of the template
type Memoize struct {
    // Key is the key to use as the caching key
    Key string `json:"key" protobuf:"bytes,1,opt,name=key"`
    // Cache sets and configures the kind of cache
    Cache *Cache `json:"cache" protobuf:"bytes,2,opt,name=cache"`
    // MaxAge is the maximum age (e.g. "180s", "24h") of an entry that is still considered valid. If an entry is older
    // than the MaxAge, it will be ignored.
    MaxAge string `json:"maxAge" protobuf:"bytes,3,opt,name=maxAge"`
}

// Cache is the configuration for the type of cache to be used
type Cache struct {
    // ConfigMap sets a ConfigMap-based cache
    ConfigMap *apiv1.ConfigMapKeySelector `json:"configMap" protobuf:"bytes,1,opt,name=configMap"`
}

// Parameter indicate a passed string parameter to a service template with an optional default value
type Parameter struct {
    // Name is the parameter name
    Name string `json:"name" protobuf:"bytes,1,opt,name=name"`

    // Default is the default value to use for an input parameter if a value was not supplied
    Default *AnyString `json:"default,omitempty" protobuf:"bytes,2,opt,name=default"`

    // Value is the literal value to use for the parameter.
    // If specified in the context of an input parameter, the value takes precedence over any passed values
    Value *AnyString `json:"value,omitempty" protobuf:"bytes,3,opt,name=value"`

    // ValueFrom is the source for the output parameter's value
    ValueFrom *ValueFrom `json:"valueFrom,omitempty" protobuf:"bytes,4,opt,name=valueFrom"`

    // GlobalName exports an output parameter to the global scope, making it available as
    // '{{workflow.outputs.parameters.XXXX}} and in workflow.status.outputs.parameters
    GlobalName string `json:"globalName,omitempty" protobuf:"bytes,5,opt,name=globalName"`

    // Enum holds a list of string values to choose from, for the actual value of the parameter
    Enum []AnyString `json:"enum,omitempty" protobuf:"bytes,6,rep,name=enum"`

    // Description is the parameter description
    Description *AnyString `json:"description,omitempty" protobuf:"bytes,7,opt,name=description"`
}

type Artifacts []Artifact

// Artifact indicates an artifact to place at a specified path
type Artifact struct {
    // name of the artifact. must be unique within a template's inputs/outputs.
    Name string `json:"name" protobuf:"bytes,1,opt,name=name"`

    // Path is the container path to the artifact
    Path string `json:"path,omitempty" protobuf:"bytes,2,opt,name=path"`

    // mode bits to use on this file, must be a value between 0 and 0777
    // set when loading input artifacts.
    Mode *int32 `json:"mode,omitempty" protobuf:"varint,3,opt,name=mode"`

    // From allows an artifact to reference an artifact from a previous step
    From string `json:"from,omitempty" protobuf:"bytes,4,opt,name=from"`

    // ArtifactLocation contains the location of the artifact
    ArtifactLocation `json:",inline" protobuf:"bytes,5,opt,name=artifactLocation"`

    // GlobalName exports an output artifact to the global scope, making it available as
    // '{{workflow.outputs.artifacts.XXXX}} and in workflow.status.outputs.artifacts
    GlobalName string `json:"globalName,omitempty" protobuf:"bytes,6,opt,name=globalName"`

    // Archive controls how the artifact will be saved to the artifact repository.
    Archive *ArchiveStrategy `json:"archive,omitempty" protobuf:"bytes,7,opt,name=archive"`

    // Make Artifacts optional, if Artifacts doesn't generate or exist
    Optional bool `json:"optional,omitempty" protobuf:"varint,8,opt,name=optional"`

    // SubPath allows an artifact to be sourced from a subpath within the specified source
    SubPath string `json:"subPath,omitempty" protobuf:"bytes,9,opt,name=subPath"`

    // If mode is set, apply the permission recursively into the artifact if it is a folder
    RecurseMode bool `json:"recurseMode,omitempty" protobuf:"varint,10,opt,name=recurseMode"`

    // FromExpression, if defined, is evaluated to specify the value for the artifact
    FromExpression string `json:"fromExpression,omitempty" protobuf:"bytes,11,opt,name=fromExpression"`

    // ArtifactGC describes the strategy to use when to deleting an artifact from completed or deleted workflows
    ArtifactGC *ArtifactGC `json:"artifactGC,omitempty" protobuf:"bytes,12,opt,name=artifactGC"`

    // Has this been deleted?
    Deleted bool `json:"deleted,omitempty" protobuf:"varint,13,opt,name=deleted"`
}

// WorkflowStep is a reference to a template to execute in a series of step
type WorkflowStep struct {
    // Name of the step
    Name string `json:"name,omitempty" protobuf:"bytes,1,opt,name=name"`

    // Template is the name of the template to execute as the step
    Template string `json:"template,omitempty" protobuf:"bytes,2,opt,name=template"`

    // Inline is the template. Template must be empty if this is declared (and vice-versa).
    Inline *Template `json:"inline,omitempty" protobuf:"bytes,13,opt,name=inline"`

    // Arguments hold arguments to the template
    Arguments Arguments `json:"arguments,omitempty" protobuf:"bytes,3,opt,name=arguments"`

    // TemplateRef is the reference to the template resource to execute as the step.
    TemplateRef *TemplateRef `json:"templateRef,omitempty" protobuf:"bytes,4,opt,name=templateRef"`

    // WithItems expands a step into multiple parallel steps from the items in the list
    WithItems []Item `json:"withItems,omitempty" protobuf:"bytes,5,rep,name=withItems"`

    // WithParam expands a step into multiple parallel steps from the value in the parameter,
    // which is expected to be a JSON list.
    WithParam string `json:"withParam,omitempty" protobuf:"bytes,6,opt,name=withParam"`

    // WithSequence expands a step into a numeric sequence
    WithSequence *Sequence `json:"withSequence,omitempty" protobuf:"bytes,7,opt,name=withSequence"`

    // When is an expression in which the step should conditionally execute
    When string `json:"when,omitempty" protobuf:"bytes,8,opt,name=when"`

    // ContinueOn makes argo to proceed with the following step even if this step fails.
    // Errors and Failed states can be specified
    ContinueOn *ContinueOn `json:"continueOn,omitempty" protobuf:"bytes,9,opt,name=continueOn"`

    // OnExit is a template reference which is invoked at the end of the
    // template, irrespective of the success, failure, or error of the
    // primary template.
    // DEPRECATED: Use Hooks[exit].Template instead.
    OnExit string `json:"onExit,omitempty" protobuf:"bytes,11,opt,name=onExit"`

    // Hooks holds the lifecycle hook which is invoked at lifecycle of
    // step, irrespective of the success, failure, or error status of the primary step
    Hooks LifecycleHooks `json:"hooks,omitempty" protobuf:"bytes,12,opt,name=hooks"`
}

// S3Artifact is the location of an S3 artifact
type S3Artifact struct {
    S3Bucket `json:",inline" protobuf:"bytes,1,opt,name=s3Bucket"`

    // Key is the key in the bucket where the artifact resides
    Key string `json:"key,omitempty" protobuf:"bytes,2,opt,name=key"`
}

// S3Bucket contains the access information required for interfacing with an S3 bucket
type S3Bucket struct {
    // Endpoint is the hostname of the bucket endpoint
    Endpoint string `json:"endpoint,omitempty" protobuf:"bytes,1,opt,name=endpoint"`

    // Bucket is the name of the bucket
    Bucket string `json:"bucket,omitempty" protobuf:"bytes,2,opt,name=bucket"`

    // Region contains the optional bucket region
    Region string `json:"region,omitempty" protobuf:"bytes,3,opt,name=region"`

    // Insecure will connect to the service with TLS
    Insecure *bool `json:"insecure,omitempty" protobuf:"varint,4,opt,name=insecure"`

    // AccessKeySecret is the secret selector to the bucket's access key
    AccessKeySecret *apiv1.SecretKeySelector `json:"accessKeySecret,omitempty" protobuf:"bytes,5,opt,name=accessKeySecret"`

    // SecretKeySecret is the secret selector to the bucket's secret key
    SecretKeySecret *apiv1.SecretKeySelector `json:"secretKeySecret,omitempty" protobuf:"bytes,6,opt,name=secretKeySecret"`

    // RoleARN is the Amazon Resource Name (ARN) of the role to assume.
    RoleARN string `json:"roleARN,omitempty" protobuf:"bytes,7,opt,name=roleARN"`

    // UseSDKCreds tells the driver to figure out credentials based on sdk defaults.
    UseSDKCreds bool `json:"useSDKCreds,omitempty" protobuf:"varint,8,opt,name=useSDKCreds"`

    // CreateBucketIfNotPresent tells the driver to attempt to create the S3 bucket for output artifacts, if it doesn't exist. Setting Enabled Encryption will apply either SSE-S3 to the bucket if KmsKeyId is not set or SSE-KMS if it is.
    CreateBucketIfNotPresent *CreateS3BucketOptions `json:"createBucketIfNotPresent,omitempty" protobuf:"bytes,9,opt,name=createBucketIfNotPresent"`

    EncryptionOptions *S3EncryptionOptions `json:"encryptionOptions,omitempty" protobuf:"bytes,10,opt,name=encryptionOptions"`
}

// GitArtifact is the location of an git artifact
type GitArtifact struct {
    // Repo is the git repository
    Repo string `json:"repo" protobuf:"bytes,1,opt,name=repo"`

    // Revision is the git commit, tag, branch to checkout
    Revision string `json:"revision,omitempty" protobuf:"bytes,2,opt,name=revision"`

    // Depth specifies clones/fetches should be shallow and include the given
    // number of commits from the branch tip
    Depth *uint64 `json:"depth,omitempty" protobuf:"bytes,3,opt,name=depth"`

    // Fetch specifies a number of refs that should be fetched before checkout
    Fetch []string `json:"fetch,omitempty" protobuf:"bytes,4,rep,name=fetch"`

    // UsernameSecret is the secret selector to the repository username
    UsernameSecret *apiv1.SecretKeySelector `json:"usernameSecret,omitempty" protobuf:"bytes,5,opt,name=usernameSecret"`

    // PasswordSecret is the secret selector to the repository password
    PasswordSecret *apiv1.SecretKeySelector `json:"passwordSecret,omitempty" protobuf:"bytes,6,opt,name=passwordSecret"`

    // SSHPrivateKeySecret is the secret selector to the repository ssh private key
    SSHPrivateKeySecret *apiv1.SecretKeySelector `json:"sshPrivateKeySecret,omitempty" protobuf:"bytes,7,opt,name=sshPrivateKeySecret"`

    // InsecureIgnoreHostKey disables SSH strict host key checking during git clone
    InsecureIgnoreHostKey bool `json:"insecureIgnoreHostKey,omitempty" protobuf:"varint,8,opt,name=insecureIgnoreHostKey"`

    // DisableSubmodules disables submodules during git clone
    DisableSubmodules bool `json:"disableSubmodules,omitempty" protobuf:"varint,9,opt,name=disableSubmodules"`

    // SingleBranch enables single branch clone, using the `branch` parameter
    SingleBranch bool `json:"singleBranch,omitempty" protobuf:"varint,10,opt,name=singleBranch"`

    // Branch is the branch to fetch when `SingleBranch` is enabled
    Branch string `json:"branch,omitempty" protobuf:"bytes,11,opt,name=branch"`
}

// HTTPArtifact allows a file served on HTTP to be placed as an input artifact in a container
type HTTPArtifact struct {
    // URL of the artifact
    URL string `json:"url" protobuf:"bytes,1,opt,name=url"`

    // Headers are an optional list of headers to send with HTTP requests for artifacts
    Headers []Header `json:"headers,omitempty" protobuf:"bytes,2,rep,name=headers"`

    // Auth contains information for client authentication
    Auth *HTTPAuth `json:"auth,omitempty" protobuf:"bytes,3,opt,name=auth"`
}

// Arguments to a template
type Arguments struct {
    // Parameters is the list of parameters to pass to the template or workflow
    // +patchStrategy=merge
    // +patchMergeKey=name
    Parameters []Parameter `json:"parameters,omitempty" patchStrategy:"merge" patchMergeKey:"name" protobuf:"bytes,1,rep,name=parameters"`

    // Artifacts is the list of artifacts to pass to the template or workflow
    // +patchStrategy=merge
    // +patchMergeKey=name
    Artifacts Artifacts `json:"artifacts,omitempty" patchStrategy:"merge" patchMergeKey:"name" protobuf:"bytes,2,rep,name=artifacts"`
}

// DAGTask represents a node in the graph during DAG execution
type DAGTask struct {
    // Name is the name of the target
    Name string `json:"name" protobuf:"bytes,1,opt,name=name"`

    // Name of template to execute
    Template string `json:"template,omitempty" protobuf:"bytes,2,opt,name=template"`

    // Inline is the template. Template must be empty if this is declared (and vice-versa).
    Inline *Template `json:"inline,omitempty" protobuf:"bytes,14,opt,name=inline"`

    // Arguments are the parameter and artifact arguments to the template
    Arguments Arguments `json:"arguments,omitempty" protobuf:"bytes,3,opt,name=arguments"`

    // TemplateRef is the reference to the template resource to execute.
    TemplateRef *TemplateRef `json:"templateRef,omitempty" protobuf:"bytes,4,opt,name=templateRef"`

    // Dependencies are name of other targets which this depends on
    Dependencies []string `json:"dependencies,omitempty" protobuf:"bytes,5,rep,name=dependencies"`

    // WithItems expands a task into multiple parallel tasks from the items in the list
    WithItems []Item `json:"withItems,omitempty" protobuf:"bytes,6,rep,name=withItems"`

    // WithParam expands a task into multiple parallel tasks from the value in the parameter,
    // which is expected to be a JSON list.
    WithParam string `json:"withParam,omitempty" protobuf:"bytes,7,opt,name=withParam"`

    // WithSequence expands a task into a numeric sequence
    WithSequence *Sequence `json:"withSequence,omitempty" protobuf:"bytes,8,opt,name=withSequence"`

    // When is an expression in which the task should conditionally execute
    When string `json:"when,omitempty" protobuf:"bytes,9,opt,name=when"`

    // ContinueOn makes argo to proceed with the following step even if this step fails.
    // Errors and Failed states can be specified
    ContinueOn *ContinueOn `json:"continueOn,omitempty" protobuf:"bytes,10,opt,name=continueOn"`

    // OnExit is a template reference which is invoked at the end of the
    // template, irrespective of the success, failure, or error of the
    // primary template.
    // DEPRECATED: Use Hooks[exit].Template instead.
    OnExit string `json:"onExit,omitempty" protobuf:"bytes,11,opt,name=onExit"`

    // Depends are name of other targets which this depends on
    Depends string `json:"depends,omitempty" protobuf:"bytes,12,opt,name=depends"`

    // Hooks hold the lifecycle hook which is invoked at lifecycle of
    // task, irrespective of the success, failure, or error status of the primary task
    Hooks LifecycleHooks `json:"hooks,omitempty" protobuf:"bytes,13,opt,name=hooks"`
}

type ContainerNode struct {
    corev1.Container `json:",inline" protobuf:"bytes,1,opt,name=container"`
    Dependencies     []string `json:"dependencies,omitempty" protobuf:"bytes,2,rep,name=dependencies"`
}

// ArchiveStrategy describes how to archive files/directory when saving artifacts
type ArchiveStrategy struct {
    Tar  *TarStrategy  `json:"tar,omitempty" protobuf:"bytes,1,opt,name=tar"`
    None *NoneStrategy `json:"none,omitempty" protobuf:"bytes,2,opt,name=none"`
    Zip  *ZipStrategy  `json:"zip,omitempty" protobuf:"bytes,3,opt,name=zip"`
}

// TarStrategy will tar and gzip the file or directory when saving
type TarStrategy struct {
    // CompressionLevel specifies the gzip compression level to use for the artifact.
    // Defaults to gzip.DefaultCompression.
    CompressionLevel *int32 `json:"compressionLevel,omitempty" protobuf:"varint,1,opt,name=compressionLevel"`
}

// ZipStrategy will unzip zipped input artifacts
type ZipStrategy struct{}

// NoneStrategy indicates to skip tar process and upload the files or directory tree as independent
// files. Note that if the artifact is a directory, the artifact driver must support the ability to
// save/load the directory appropriately.
type NoneStrategy struct{}

// ValueFrom describes a location in which to obtain the value to a parameter
type ValueFrom struct {
    // Path in the container to retrieve an output parameter value from in container templates
    Path string `json:"path,omitempty" protobuf:"bytes,1,opt,name=path"`

    // JSONPath of a resource to retrieve an output parameter value from in resource templates
    JSONPath string `json:"jsonPath,omitempty" protobuf:"bytes,2,opt,name=jsonPath"`

    // JQFilter expression against the resource object in resource templates
    JQFilter string `json:"jqFilter,omitempty" protobuf:"bytes,3,opt,name=jqFilter"`

    // Selector (https://github.com/expr-lang/expr) that is evaluated against the event to get the value of the parameter. E.g. `payload.message`
    Event string `json:"event,omitempty" protobuf:"bytes,7,opt,name=event"`

    // Parameter reference to a step or dag task in which to retrieve an output parameter value from
    // (e.g. '{{steps.mystep.outputs.myparam}}')
    Parameter string `json:"parameter,omitempty" protobuf:"bytes,4,opt,name=parameter"`

    // Supplied value to be filled in directly, either through the CLI, API, etc.
    Supplied *SuppliedValueFrom `json:"supplied,omitempty" protobuf:"bytes,6,opt,name=supplied"`

    // ConfigMapKeyRef is configmap selector for input parameter configuration
    ConfigMapKeyRef *apiv1.ConfigMapKeySelector `json:"configMapKeyRef,omitempty" protobuf:"bytes,9,opt,name=configMapKeyRef"`

    // Default specifies a value to be used if retrieving the value from the specified source fails
    Default *AnyString `json:"default,omitempty" protobuf:"bytes,5,opt,name=default"`

    // Expression, if defined, is evaluated to specify the value for the parameter
    Expression string `json:"expression,omitempty" protobuf:"bytes,8,rep,name=expression"`
}

// WorkflowTemplateRef is a reference to a WorkflowTemplate resource.
type WorkflowTemplateRef struct {
    // Name is the resource name of the workflow template.
    Name string `json:"name,omitempty" protobuf:"bytes,1,opt,name=name"`
    // ClusterScope indicates the referred template is cluster scoped (i.e. a ClusterWorkflowTemplate).
    ClusterScope bool `json:"clusterScope,omitempty" protobuf:"varint,2,opt,name=clusterScope"`
}

// PodGC describes how to delete completed pods as they complete
type PodGC struct {
    // Strategy is the strategy to use. One of "OnPodCompletion", "OnPodSuccess", "OnWorkflowCompletion", "OnWorkflowSuccess". If unset, does not delete Pods
    Strategy PodGCStrategy `json:"strategy,omitempty" protobuf:"bytes,1,opt,name=strategy,casttype=PodGCStrategy"`
    // LabelSelector is the label selector to check if the pods match the labels before being added to the pod GC queue.
    LabelSelector *metav1.LabelSelector `json:"labelSelector,omitempty" protobuf:"bytes,2,opt,name=labelSelector"`
    // DeleteDelayDuration specifies the duration before pods in the GC queue get deleted.
    DeleteDelayDuration *metav1.Duration `json:"deleteDelayDuration,omitempty" protobuf:"bytes,3,opt,name=deleteDelayDuration"`
}

// PodGCStrategy is the strategy when to delete completed pods for GC.
type PodGCStrategy string

// PodGCStrategy
const (
    PodGCOnPodNone            PodGCStrategy = ""
    PodGCOnPodCompletion      PodGCStrategy = "OnPodCompletion"
    PodGCOnPodSuccess         PodGCStrategy = "OnPodSuccess"
    PodGCOnWorkflowCompletion PodGCStrategy = "OnWorkflowCompletion"
    PodGCOnWorkflowSuccess    PodGCStrategy = "OnWorkflowSuccess"
)

// TTLStrategy is the strategy for the time to live depending on if the workflow succeeded or failed
type TTLStrategy struct {
    // SecondsAfterCompletion is the number of seconds to live after completion
    SecondsAfterCompletion *int32 `json:"secondsAfterCompletion,omitempty" protobuf:"bytes,1,opt,name=secondsAfterCompletion"`
    // SecondsAfterSuccess is the number of seconds to live after success
    SecondsAfterSuccess *int32 `json:"secondsAfterSuccess,omitempty" protobuf:"bytes,2,opt,name=secondsAfterSuccess"`
    // SecondsAfterFailure is the number of seconds to live after failure
    SecondsAfterFailure *int32 `json:"secondsAfterFailure,omitempty" protobuf:"bytes,3,opt,name=secondsAfterFailure"`
}

// ArtifactGCStrategy is the strategy when to delete artifacts for GC.
type ArtifactGCStrategy string

// ArtifactGCStrategy
const (
    ArtifactGCOnWorkflowCompletion ArtifactGCStrategy = "OnWorkflowCompletion"
    ArtifactGCOnWorkflowDeletion   ArtifactGCStrategy = "OnWorkflowDeletion"
    ArtifactGCNever                ArtifactGCStrategy = "Never"
    ArtifactGCStrategyUndefined    ArtifactGCStrategy = ""
)

// ArtifactGC describes how to delete artifacts from completed Workflows - this is embedded into the WorkflowLevelArtifactGC, and also used for individual Artifacts to override that as needed
type ArtifactGC struct {
    // Strategy is the strategy to use.
    // +kubebuilder:validation:Enum="";OnWorkflowCompletion;OnWorkflowDeletion;Never
    Strategy ArtifactGCStrategy `json:"strategy,omitempty" protobuf:"bytes,1,opt,name=strategy,casttype=ArtifactGCStategy"`

    // PodMetadata is an optional field for specifying the Labels and Annotations that should be assigned to the Pod doing the deletion
    PodMetadata *Metadata `json:"podMetadata,omitempty" protobuf:"bytes,2,opt,name=podMetadata"`

    // ServiceAccountName is an optional field for specifying the Service Account that should be assigned to the Pod doing the deletion
    ServiceAccountName string `json:"serviceAccountName,omitempty" protobuf:"bytes,3,opt,name=serviceAccountName"`
}