Day 2 / May 17 (Tue)¶
Live-Coding Session¶
A live-coding session of Demo: Running Spark Examples on minikube by Krzysiek.
Invalid value: "TYPE=ssh"¶
During the session we faced the following issue that we eventually managed to sort out by reviewing the source code of Spark on Kubernetes (namely org.apache.spark.deploy.k8s.submit.KubernetesClientUtils).
22/05/17 09:26:36 INFO SparkKubernetesClientFactory: Auto-configuring K8S client using current context from users K8S config file
22/05/17 09:26:38 INFO KerberosConfDriverFeatureStep: You have not specified a krb5.conf file locally or via a ConfigMap. Make sure that you have the krb5.conf locally on the driver image.
22/05/17 09:26:39 INFO KubernetesClientUtils: Spark configuration files loaded from Some(/home/adform/spark/conf) : spark-env.sh
Exception in thread "main" io.fabric8.kubernetes.client.KubernetesClientException: Failure executing: POST at: https://127.0.0.1:56811/api/v1/namespaces/spark-demo/configmaps. Message: ConfigMap "a1-a0a2c280d0e95f2a-hadoop-config" is invalid: data[TYPE=ssh]: Invalid value: "TYPE=ssh": a valid config key must consist of alphanumeric characters, '-', '_' or '.' (e.g. 'key.name', or 'KEY_NAME', or 'key-name', regex used for validation is '[-._a-zA-Z0-9]+'). Received status: Status(apiVersion=v1, code=422, details=StatusDetails(causes=[StatusCause(field=data[TYPE=ssh], message=Invalid value: "TYPE=ssh": a valid config key must consist of alphanumeric characters, '-', '_' or '.' (e.g. 'key.name', or 'KEY_NAME', or 'key-name', regex used for validation is '[-._a-zA-Z0-9]+'), reason=FieldValueInvalid, additionalProperties={})], group=null, kind=ConfigMap, name=a1-a0a2c280d0e95f2a-hadoop-config, retryAfterSeconds=null, uid=null, additionalProperties={}), kind=Status, message=ConfigMap "a1-a0a2c280d0e95f2a-hadoop-config" is invalid: data[TYPE=ssh]: Invalid value: "TYPE=ssh": a valid config key must consist of alphanumeric characters, '-', '_' or '.' (e.g. 'key.name', or 'KEY_NAME', or 'key-name', regex used for validation is '[-._a-zA-Z0-9]+'), metadata=ListMeta(_continue=null, remainingItemCount=null, resourceVersion=null, selfLink=null, additionalProperties={}), reason=Invalid, status=Failure, additionalProperties={}).
at io.fabric8.kubernetes.client.dsl.base.OperationSupport.requestFailure(OperationSupport.java:639)
at io.fabric8.kubernetes.client.dsl.base.OperationSupport.assertResponseCode(OperationSupport.java:578)
at io.fabric8.kubernetes.client.dsl.base.OperationSupport.handleResponse(OperationSupport.java:543)
at io.fabric8.kubernetes.client.dsl.base.OperationSupport.handleResponse(OperationSupport.java:504)
at io.fabric8.kubernetes.client.dsl.base.OperationSupport.handleCreate(OperationSupport.java:292)
at io.fabric8.kubernetes.client.dsl.base.BaseOperation.handleCreate(BaseOperation.java:893)
at io.fabric8.kubernetes.client.dsl.base.BaseOperation.create(BaseOperation.java:357)
at io.fabric8.kubernetes.client.dsl.base.BaseOperation.create(BaseOperation.java:86)
at io.fabric8.kubernetes.client.handlers.core.v1.ConfigMapHandler.create(ConfigMapHandler.java:39)
at io.fabric8.kubernetes.client.handlers.core.v1.ConfigMapHandler.create(ConfigMapHandler.java:25)
at io.fabric8.kubernetes.client.utils.CreateOrReplaceHelper.lambda$createOrReplaceItem$0(CreateOrReplaceHelper.java:77)
at io.fabric8.kubernetes.client.utils.CreateOrReplaceHelper.createOrReplace(CreateOrReplaceHelper.java:56)
at io.fabric8.kubernetes.client.utils.CreateOrReplaceHelper.createOrReplaceItem(CreateOrReplaceHelper.java:91)
at io.fabric8.kubernetes.client.dsl.internal.NamespaceVisitFromServerGetWatchDeleteRecreateWaitApplicableListImpl.createOrReplaceOrDeleteExisting(NamespaceVisitFromServerGetWatchDeleteRecreateWaitApplicableListImpl.java:454)
at io.fabric8.kubernetes.client.dsl.internal.NamespaceVisitFromServerGetWatchDeleteRecreateWaitApplicableListImpl.createOrReplace(NamespaceVisitFromServerGetWatchDeleteRecreateWaitApplicableListImpl.java:297)
at io.fabric8.kubernetes.client.dsl.internal.NamespaceVisitFromServerGetWatchDeleteRecreateWaitApplicableListImpl.createOrReplace(NamespaceVisitFromServerGetWatchDeleteRecreateWaitApplicableListImpl.java:66)
at org.apache.spark.deploy.k8s.submit.Client.run(KubernetesClientApplication.scala:150)
at org.apache.spark.deploy.k8s.submit.KubernetesClientApplication.$anonfun$run$4(KubernetesClientApplication.scala:220)
at org.apache.spark.deploy.k8s.submit.KubernetesClientApplication.$anonfun$run$4$adapted(KubernetesClientApplication.scala:214)
at org.apache.spark.util.Utils$.tryWithResource(Utils.scala:2713)
at org.apache.spark.deploy.k8s.submit.KubernetesClientApplication.run(KubernetesClientApplication.scala:214)
at org.apache.spark.deploy.k8s.submit.KubernetesClientApplication.start(KubernetesClientApplication.scala:186)
at org.apache.spark.deploy.SparkSubmit.org$apache$spark$deploy$SparkSubmit$$runMain(SparkSubmit.scala:955)
at org.apache.spark.deploy.SparkSubmit.doRunMain$1(SparkSubmit.scala:180)
at org.apache.spark.deploy.SparkSubmit.submit(SparkSubmit.scala:203)
at org.apache.spark.deploy.SparkSubmit.doSubmit(SparkSubmit.scala:90)
at org.apache.spark.deploy.SparkSubmit$$anon$2.doSubmit(SparkSubmit.scala:1043)
at org.apache.spark.deploy.SparkSubmit$.main(SparkSubmit.scala:1052)
at org.apache.spark.deploy.SparkSubmit.main(SparkSubmit.scala)
The issue was an environment variable that pointed out at a directory with configuration files that should not have been loaded. Call it a misconfiguration of Spark on Kubernetes.
Scala Exercises¶
Using PATH Environment Variable¶
Write a function that accepts a path (of type String) and returns a Boolean value whether the path is in the PATH environment variable or not. Use sys.env.
File Directories¶
Write a function that accepts a file name (String) and returns the directories it is in (in PATH environment variable). The function should return all the paths with the file.
Find a solution in solutions/path-utils project.
This project uses the following: