rancher-partner-charts/charts/bitnami/spark/README.md

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Apache Spark packaged by Bitnami

Apache Spark is a high-performance engine for large-scale computing tasks, such as data processing, machine learning and real-time data streaming. It includes APIs for Java, Python, Scala and R.

Overview of Apache Spark

Trademarks: This software listing is packaged by Bitnami. The respective trademarks mentioned in the offering are owned by the respective companies, and use of them does not imply any affiliation or endorsement.

TL;DR

$ helm repo add my-repo https://charts.bitnami.com/bitnami
$ helm install my-release my-repo/spark

Introduction

This chart bootstraps an Apache Spark deployment on a Kubernetes cluster using the Helm package manager.

Apache Spark includes APIs for Java, Python, Scala and R.

Bitnami charts can be used with Kubeapps for deployment and management of Helm Charts in clusters.

Prerequisites

  • Kubernetes 1.19+
  • Helm 3.2.0+

Installing the Chart

To install the chart with the release name my-release:

$ helm repo add my-repo https://charts.bitnami.com/bitnami
$ helm install my-release my-repo/spark

These commands deploy Apache Spark on the Kubernetes cluster in the default configuration. The Parameters section lists the parameters that can be configured during installation.

Tip: List all releases using helm list

Uninstalling the Chart

To uninstall/delete the my-release statefulset:

$ helm delete my-release

The command removes all the Kubernetes components associated with the chart and deletes the release. Use the option --purge to delete all persistent volumes too.

Parameters

Global parameters

Name Description Value
global.imageRegistry Global Docker image registry ""
global.imagePullSecrets Global Docker registry secret names as an array []
global.storageClass Global StorageClass for Persistent Volume(s) ""

Common parameters

Name Description Value
kubeVersion Force target Kubernetes version (using Helm capabilities if not set) ""
nameOverride String to partially override common.names.fullname template (will maintain the release name) ""
fullnameOverride String to fully override common.names.fullname template ""
namespaceOverride String to fully override common.names.namespace ""
commonLabels Labels to add to all deployed objects {}
commonAnnotations Annotations to add to all deployed objects {}
clusterDomain Kubernetes cluster domain name cluster.local
extraDeploy Array of extra objects to deploy with the release []
initScripts Dictionary of init scripts. Evaluated as a template. {}
initScriptsCM ConfigMap with the init scripts. Evaluated as a template. ""
initScriptsSecret Secret containing /docker-entrypoint-initdb.d scripts to be executed at initialization time that contain sensitive data. Evaluated as a template. ""
diagnosticMode.enabled Enable diagnostic mode (all probes will be disabled and the command will be overridden) false
diagnosticMode.command Command to override all containers in the deployment ["sleep"]
diagnosticMode.args Args to override all containers in the deployment ["infinity"]

Spark parameters

Name Description Value
image.registry Spark image registry docker.io
image.repository Spark image repository bitnami/spark
image.tag Spark image tag (immutable tags are recommended) 3.3.1-debian-11-r14
image.digest Spark image digest in the way sha256:aa.... Please note this parameter, if set, will override the tag ""
image.pullPolicy Spark image pull policy IfNotPresent
image.pullSecrets Specify docker-registry secret names as an array []
image.debug Enable image debug mode false
hostNetwork Enable HOST Network false

Spark master parameters

Name Description Value
master.existingConfigmap The name of an existing ConfigMap with your custom configuration for master ""
master.containerPorts.http Specify the port where the web interface will listen on the master over HTTP 8080
master.containerPorts.https Specify the port where the web interface will listen on the master over HTTPS 8480
master.containerPorts.cluster Specify the port where the master listens to communicate with workers 7077
master.hostAliases Deployment pod host aliases []
master.extraContainerPorts Specify the port where the running jobs inside the masters listens []
master.daemonMemoryLimit Set the memory limit for the master daemon ""
master.configOptions Use a string to set the config options for in the form "-Dx=y" ""
master.extraEnvVars Extra environment variables to pass to the master container []
master.extraEnvVarsCM Name of existing ConfigMap containing extra env vars for master nodes ""
master.extraEnvVarsSecret Name of existing Secret containing extra env vars for master nodes ""
master.podSecurityContext.enabled Enable security context true
master.podSecurityContext.fsGroup Set master pod's Security Context Group ID 1001
master.podSecurityContext.runAsUser Set master pod's Security Context User ID 1001
master.podSecurityContext.runAsGroup Set master pod's Security Context Group ID 0
master.podSecurityContext.seLinuxOptions Set master pod's Security Context SELinux options {}
master.containerSecurityContext.enabled Enabled master containers' Security Context true
master.containerSecurityContext.runAsUser Set master containers' Security Context runAsUser 1001
master.containerSecurityContext.runAsNonRoot Set master containers' Security Context runAsNonRoot true
master.containerSecurityContext.readOnlyRootFilesystem Set master containers' Security Context runAsNonRoot false
master.command Override default container command (useful when using custom images) []
master.args Override default container args (useful when using custom images) []
master.podAnnotations Annotations for pods in StatefulSet {}
master.podLabels Extra labels for pods in StatefulSet {}
master.podAffinityPreset Spark master pod affinity preset. Ignored if master.affinity is set. Allowed values: soft or hard ""
master.podAntiAffinityPreset Spark master pod anti-affinity preset. Ignored if master.affinity is set. Allowed values: soft or hard soft
master.nodeAffinityPreset.type Spark master node affinity preset type. Ignored if master.affinity is set. Allowed values: soft or hard ""
master.nodeAffinityPreset.key Spark master node label key to match Ignored if master.affinity is set. ""
master.nodeAffinityPreset.values Spark master node label values to match. Ignored if master.affinity is set. []
master.affinity Spark master affinity for pod assignment {}
master.nodeSelector Spark master node labels for pod assignment {}
master.tolerations Spark master tolerations for pod assignment []
master.updateStrategy.type Master statefulset strategy type. RollingUpdate
master.priorityClassName master pods' priorityClassName ""
master.topologySpreadConstraints Topology Spread Constraints for pod assignment spread across your cluster among failure-domains. Evaluated as a template []
master.schedulerName Name of the k8s scheduler (other than default) for master pods ""
master.terminationGracePeriodSeconds Seconds Redmine pod needs to terminate gracefully ""
master.lifecycleHooks for the master container(s) to automate configuration before or after startup {}
master.extraVolumes Optionally specify extra list of additional volumes for the master pod(s) []
master.extraVolumeMounts Optionally specify extra list of additional volumeMounts for the master container(s) []
master.resources.limits The resources limits for the container {}
master.resources.requests The requested resources for the container {}
master.livenessProbe.enabled Enable livenessProbe true
master.livenessProbe.initialDelaySeconds Initial delay seconds for livenessProbe 180
master.livenessProbe.periodSeconds Period seconds for livenessProbe 20
master.livenessProbe.timeoutSeconds Timeout seconds for livenessProbe 5
master.livenessProbe.failureThreshold Failure threshold for livenessProbe 6
master.livenessProbe.successThreshold Success threshold for livenessProbe 1
master.readinessProbe.enabled Enable readinessProbe true
master.readinessProbe.initialDelaySeconds Initial delay seconds for readinessProbe 30
master.readinessProbe.periodSeconds Period seconds for readinessProbe 10
master.readinessProbe.timeoutSeconds Timeout seconds for readinessProbe 5
master.readinessProbe.failureThreshold Failure threshold for readinessProbe 6
master.readinessProbe.successThreshold Success threshold for readinessProbe 1
master.startupProbe.enabled Enable startupProbe false
master.startupProbe.initialDelaySeconds Initial delay seconds for startupProbe 30
master.startupProbe.periodSeconds Period seconds for startupProbe 10
master.startupProbe.timeoutSeconds Timeout seconds for startupProbe 5
master.startupProbe.failureThreshold Failure threshold for startupProbe 6
master.startupProbe.successThreshold Success threshold for startupProbe 1
master.customLivenessProbe Custom livenessProbe that overrides the default one {}
master.customReadinessProbe Custom readinessProbe that overrides the default one {}
master.customStartupProbe Custom startupProbe that overrides the default one {}
master.sidecars Add additional sidecar containers to the master pod(s) []
master.initContainers Add initContainers to the master pods. []

Spark worker parameters

Name Description Value
worker.existingConfigmap The name of an existing ConfigMap with your custom configuration for workers ""
worker.containerPorts.http Specify the port where the web interface will listen on the worker over HTTP 8080
worker.containerPorts.https Specify the port where the web interface will listen on the worker over HTTPS 8480
worker.containerPorts.cluster Specify the port where the worker listens to communicate with workers ""
worker.hostAliases Add deployment host aliases []
worker.extraContainerPorts Specify the port where the running jobs inside the workers listens []
worker.daemonMemoryLimit Set the memory limit for the worker daemon ""
worker.memoryLimit Set the maximum memory the worker is allowed to use ""
worker.coreLimit Se the maximum number of cores that the worker can use ""
worker.dir Set a custom working directory for the application ""
worker.javaOptions Set options for the JVM in the form -Dx=y ""
worker.configOptions Set extra options to configure the worker in the form -Dx=y ""
worker.extraEnvVars An array to add extra env vars []
worker.extraEnvVarsCM Name of existing ConfigMap containing extra env vars for worker nodes ""
worker.extraEnvVarsSecret Name of existing Secret containing extra env vars for worker nodes ""
worker.replicaCount Number of spark workers (will be the minimum number when autoscaling is enabled) 2
worker.podSecurityContext.enabled Enable security context true
worker.podSecurityContext.fsGroup Group ID for the container 1001
worker.podSecurityContext.runAsUser User ID for the container 1001
worker.podSecurityContext.runAsGroup Group ID for the container 0
worker.podSecurityContext.seLinuxOptions SELinux options for the container {}
worker.containerSecurityContext.enabled Enabled worker containers' Security Context true
worker.containerSecurityContext.runAsUser Set worker containers' Security Context runAsUser 1001
worker.containerSecurityContext.runAsNonRoot Set worker containers' Security Context runAsNonRoot true
worker.containerSecurityContext.readOnlyRootFilesystem Set worker containers' Security Context runAsNonRoot false
worker.command Override default container command (useful when using custom images) []
worker.args Override default container args (useful when using custom images) []
worker.podAnnotations Annotations for pods in StatefulSet {}
worker.podLabels Extra labels for pods in StatefulSet {}
worker.podAffinityPreset Spark worker pod affinity preset. Ignored if worker.affinity is set. Allowed values: soft or hard ""
worker.podAntiAffinityPreset Spark worker pod anti-affinity preset. Ignored if worker.affinity is set. Allowed values: soft or hard soft
worker.nodeAffinityPreset.type Spark worker node affinity preset type. Ignored if worker.affinity is set. Allowed values: soft or hard ""
worker.nodeAffinityPreset.key Spark worker node label key to match Ignored if worker.affinity is set. ""
worker.nodeAffinityPreset.values Spark worker node label values to match. Ignored if worker.affinity is set. []
worker.affinity Spark worker affinity for pod assignment {}
worker.nodeSelector Spark worker node labels for pod assignment {}
worker.tolerations Spark worker tolerations for pod assignment []
worker.updateStrategy.type Worker statefulset strategy type. RollingUpdate
worker.podManagementPolicy Statefulset Pod Management Policy Type OrderedReady
worker.priorityClassName worker pods' priorityClassName ""
worker.topologySpreadConstraints Topology Spread Constraints for pod assignment spread across your cluster among failure-domains. Evaluated as a template []
worker.schedulerName Name of the k8s scheduler (other than default) for worker pods ""
worker.terminationGracePeriodSeconds Seconds Redmine pod needs to terminate gracefully ""
worker.lifecycleHooks for the worker container(s) to automate configuration before or after startup {}
worker.extraVolumes Optionally specify extra list of additional volumes for the worker pod(s) []
worker.extraVolumeMounts Optionally specify extra list of additional volumeMounts for the master container(s) []
worker.resources.limits The resources limits for the container {}
worker.resources.requests The requested resources for the container {}
worker.livenessProbe.enabled Enable livenessProbe true
worker.livenessProbe.initialDelaySeconds Initial delay seconds for livenessProbe 180
worker.livenessProbe.periodSeconds Period seconds for livenessProbe 20
worker.livenessProbe.timeoutSeconds Timeout seconds for livenessProbe 5
worker.livenessProbe.failureThreshold Failure threshold for livenessProbe 6
worker.livenessProbe.successThreshold Success threshold for livenessProbe 1
worker.readinessProbe.enabled Enable readinessProbe true
worker.readinessProbe.initialDelaySeconds Initial delay seconds for readinessProbe 30
worker.readinessProbe.periodSeconds Period seconds for readinessProbe 10
worker.readinessProbe.timeoutSeconds Timeout seconds for readinessProbe 5
worker.readinessProbe.failureThreshold Failure threshold for readinessProbe 6
worker.readinessProbe.successThreshold Success threshold for readinessProbe 1
worker.startupProbe.enabled Enable startupProbe true
worker.startupProbe.initialDelaySeconds Initial delay seconds for startupProbe 30
worker.startupProbe.periodSeconds Period seconds for startupProbe 10
worker.startupProbe.timeoutSeconds Timeout seconds for startupProbe 5
worker.startupProbe.failureThreshold Failure threshold for startupProbe 6
worker.startupProbe.successThreshold Success threshold for startupProbe 1
worker.customLivenessProbe Custom livenessProbe that overrides the default one {}
worker.customReadinessProbe Custom readinessProbe that overrides the default one {}
worker.customStartupProbe Custom startupProbe that overrides the default one {}
worker.sidecars Add additional sidecar containers to the worker pod(s) []
worker.initContainers Add initContainers to the worker pods. []
worker.autoscaling.enabled Enable replica autoscaling depending on CPU false
worker.autoscaling.minReplicas Minimum number of worker replicas ""
worker.autoscaling.maxReplicas Maximum number of worker replicas 5
worker.autoscaling.targetCPU Target CPU utilization percentage 50
worker.autoscaling.targetMemory Target Memory utilization percentage ""

Security parameters

Name Description Value
security.passwordsSecretName Name of the secret that contains all the passwords ""
security.rpc.authenticationEnabled Enable the RPC authentication false
security.rpc.encryptionEnabled Enable the encryption for RPC false
security.storageEncryptionEnabled Enables local storage encryption false
security.certificatesSecretName Name of the secret that contains the certificates. ""
security.ssl.enabled Enable the SSL configuration false
security.ssl.needClientAuth Enable the client authentication false
security.ssl.protocol Set the SSL protocol TLSv1.2
security.ssl.existingSecret Name of the existing secret containing the TLS certificates ""
security.ssl.autoGenerated Create self-signed TLS certificates. Currently only supports PEM certificates false
security.ssl.keystorePassword Set the password of the JKS Keystore ""
security.ssl.truststorePassword Truststore password. ""
security.ssl.resources.limits The resources limits for the container {}
security.ssl.resources.requests The requested resources for the container {}

Traffic Exposure parameters

Name Description Value
service.type Kubernetes Service type ClusterIP
service.ports.http Spark client port for HTTP 80
service.ports.https Spark client port for HTTPS 443
service.ports.cluster Spark cluster port 7077
service.nodePorts.http Kubernetes web node port for HTTP ""
service.nodePorts.https Kubernetes web node port for HTTPS ""
service.nodePorts.cluster Kubernetes cluster node port ""
service.clusterIP Spark service Cluster IP ""
service.loadBalancerIP Load balancer IP if spark service type is LoadBalancer ""
service.loadBalancerSourceRanges Spark service Load Balancer sources []
service.externalTrafficPolicy Spark service external traffic policy Cluster
service.annotations Additional custom annotations for Spark service {}
service.extraPorts Extra ports to expose in Spark service (normally used with the sidecars value) []
service.sessionAffinity Control where client requests go, to the same pod or round-robin None
service.sessionAffinityConfig Additional settings for the sessionAffinity {}
ingress.enabled Enable ingress controller resource false
ingress.pathType Ingress path type ImplementationSpecific
ingress.apiVersion Force Ingress API version (automatically detected if not set) ""
ingress.hostname Default host for the ingress resource spark.local
ingress.ingressClassName IngressClass that will be be used to implement the Ingress (Kubernetes 1.18+) ""
ingress.path The Path to Spark. You may need to set this to '/*' in order to use this with ALB ingress controllers. /
ingress.annotations Additional annotations for the Ingress resource. To enable certificate autogeneration, place here your cert-manager annotations. {}
ingress.tls Enable TLS configuration for the hostname defined at ingress.hostname parameter false
ingress.selfSigned Create a TLS secret for this ingress record using self-signed certificates generated by Helm false
ingress.extraHosts The list of additional hostnames to be covered with this ingress record. []
ingress.extraPaths Any additional arbitrary paths that may need to be added to the ingress under the main host. []
ingress.extraTls The tls configuration for additional hostnames to be covered with this ingress record. []
ingress.secrets If you're providing your own certificates, please use this to add the certificates as secrets []
ingress.extraRules Additional rules to be covered with this ingress record []

Other parameters

Name Description Value
serviceAccount.create Enable the creation of a ServiceAccount for Spark pods true
serviceAccount.name The name of the ServiceAccount to use. ""
serviceAccount.annotations Annotations for Spark Service Account {}
serviceAccount.automountServiceAccountToken Automount API credentials for a service account. true

Metrics parameters

Name Description Value
metrics.enabled Start a side-car prometheus exporter false
metrics.masterAnnotations Annotations for the Prometheus metrics on master nodes {}
metrics.workerAnnotations Annotations for the Prometheus metrics on worker nodes {}
metrics.podMonitor.enabled If the operator is installed in your cluster, set to true to create a PodMonitor Resource for scraping metrics using PrometheusOperator false
metrics.podMonitor.extraMetricsEndpoints Add metrics endpoints for monitoring the jobs running in the worker nodes []
metrics.podMonitor.namespace Specify the namespace in which the podMonitor resource will be created ""
metrics.podMonitor.interval Specify the interval at which metrics should be scraped 30s
metrics.podMonitor.scrapeTimeout Specify the timeout after which the scrape is ended ""
metrics.podMonitor.additionalLabels Additional labels that can be used so PodMonitors will be discovered by Prometheus {}
metrics.prometheusRule.enabled Set this to true to create prometheusRules for Prometheus false
metrics.prometheusRule.namespace Namespace where the prometheusRules resource should be created ""
metrics.prometheusRule.additionalLabels Additional labels that can be used so prometheusRules will be discovered by Prometheus {}
metrics.prometheusRule.rules Custom Prometheus rules []

Specify each parameter using the --set key=value[,key=value] argument to helm install. For example,

$ helm install my-release \
  --set master.webPort=8081 my-repo/spark

The above command sets the spark master web port to 8081.

Alternatively, a YAML file that specifies the values for the parameters can be provided while installing the chart. For example,

$ helm install my-release -f values.yaml my-repo/spark

Tip: You can use the default values.yaml

Configuration and installation details

Rolling vs Immutable tags

It is strongly recommended to use immutable tags in a production environment. This ensures your deployment does not change automatically if the same tag is updated with a different image.

Bitnami will release a new chart updating its containers if a new version of the main container, significant changes, or critical vulnerabilities exist.

Define custom configuration

To use a custom configuration, a ConfigMap should be created with the spark-env.sh file inside the ConfigMap. The ConfigMap name must be provided at deployment time.

To set the configuration on the master use master.configurationConfigMap=configMapName. To set the configuration on the worker, use worker.configurationConfigMap=configMapName.

These values can be set at the same time in a single ConfigMap or using two ConfigMaps. An additional spark-defaults.conf file can be provided in the ConfigMap. You can use both files or one without the other.

Submit an application

To submit an application to the Apache Spark cluster, use the spark-submit script, which is available at https://github.com/apache/spark/tree/master/bin.

The command below illustrates the process of deploying one of the sample applications included with Apache Spark. Replace the k8s-apiserver-host, k8s-apiserver-port, spark-master-svc, and spark-master-port placeholders with the correct master host/IP address and port for your deployment.

$ ./bin/spark-submit \
    --class org.apache.spark.examples.SparkPi \
    --conf spark.kubernetes.container.image=bitnami/spark:3 \
    --master k8s://https://k8s-apiserver-host:k8s-apiserver-port \
    --conf spark.kubernetes.driverEnv.SPARK_MASTER_URL=spark://spark-master-svc:spark-master-port \
    --deploy-mode cluster \
    ./examples/jars/spark-examples_2.12-3.2.0.jar 1000

This command example assumes that you have downloaded a Spark binary distribution, which can be found at Download Apache Spark.

For a complete walkthrough of the process using a custom application, refer to the detailed Apache Spark tutorial or Spark's guide to Running Spark on Kubernetes.

Be aware that it is currently not possible to submit an application to a standalone cluster if RPC authentication is configured. Learn more about the issue.

Configuring Spark Master as reverse proxy

Spark offers configuration to enable running Spark Master as reverse proxy for worker and application UIs. This can be useful as the Spark Master UI may otherwise use private IPv4 addresses for links to Spark workers and Spark apps.

Coupled with ingress configuration, you can set master.configOptions and worker.configOptions to tell Spark to reverse proxy the worker and application UIs to enable access without requiring direct access to their hosts:

master:
  configOptions:
    -Dspark.ui.reverseProxy=true
    -Dspark.ui.reverseProxyUrl=https://spark.your-domain.com
worker:
  configOptions:
    -Dspark.ui.reverseProxy=true
    -Dspark.ui.reverseProxyUrl=https://spark.your-domain.com
ingress:
  enabled: true
  hostname: spark.your-domain.com

See the Spark Configuration docs for detail on the parameters.

Configure security for Apache Spark

Configure SSL communication

In order to enable secure transport between workers and master, deploy the Helm chart with the ssl.enabled=true chart parameter.

Create certificate and password secrets

It is necessary to create two secrets for the passwords and certificates. The names of the two secrets should be configured using the security.passwordsSecretName and security.ssl.existingSecret chart parameters.

The keys for the certificate secret must be named spark-keystore.jks and spark-truststore.jks, and the content must be text in JKS format. Use this script to generate certificates for test purposes if required.

The secret for passwords should have three keys: rpc-authentication-secret, ssl-keystore-password and ssl-truststore-password.

Refer to the chart documentation for more details on configuring security and an example.

It is currently not possible to submit an application to a standalone cluster if RPC authentication is configured. Learn more about this issue.

Set Pod affinity

This chart allows you to set your custom affinity using the XXX.affinity parameter(s). Find more information about Pod affinity in the Kubernetes documentation.

As an alternative, you can use the preset configurations for pod affinity, pod anti-affinity, and node affinity available at the bitnami/common chart. To do so, set the XXX.podAffinityPreset, XXX.podAntiAffinityPreset, or XXX.nodeAffinityPreset parameters.

Troubleshooting

Find more information about how to deal with common errors related to Bitnami's Helm charts in this troubleshooting guide.

Upgrading

To 6.0.0

This chart major version standarizes the chart templates and values, modifying some existing parameters names and adding several more. These parameter modifications can be sumarised in the following:

  • worker.autoscaling.CpuTargetPercentage/.replicasMax parameters are now found by worker.autoscaling.targetCPU/.maxReplicas.
  • webport/webPortHttps/cluster parameters are now found by containerPorts.http/.https/.cluster.
  • service.webport/webPortHttps/cluster parameters are now found by service.ports.http/.https/.cluster.
  • service.nodePorts.web/webHttps/cluster parameters are now found by service.nodePorts.http/.https/.cluster.
  • xxxxx.securityContext parameters are now under xxxxx.podSecurityContext
  • xxxxx.configurationConfigMap parameter has been renamed to xxxxx.existingConfigmap
  • extraPodLabels parameter has been renamed to podLabels

Besides the changes detailed above, no issues are expected to appear when upgrading.

To 5.0.0

This version standardizes the way of defining Ingress rules. When configuring a single hostname for the Ingress rule, set the ingress.hostname value. When defining more than one, set the ingress.extraHosts array. Apart from this case, no issues are expected to appear when upgrading.

To 4.0.0

On November 13, 2020, Helm v2 support formally ended. This major version is the result of the required changes applied to the Helm Chart to be able to incorporate the different features added in Helm v3 and to be consistent with the Helm project itself regarding the Helm v2 EOL.

Learn more about this change and related upgrade considerations.

To 3.0.0

  • This version introduces bitnami/common, a library chart as a dependency. More documentation about this new utility could be found here. Please, make sure that you have updated the chart dependencies before executing any upgrade.

  • Spark container images are updated to use Hadoop 3.2.x: Notable Changes: 3.0.0-debian-10-r44

Note: Backwards compatibility is not guaranteed due to the above mentioned changes. Please make sure your workloads are compatible with the new version of Hadoop before upgrading. Backups are always recommended before any upgrade operation.

License

Copyright © 2022 Bitnami

Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at

http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.