simply about difficult
In this article, we are going to figure out, how to delete PushGateway metrics/groups. Let’s also answer the question – why “PushGateway metrics delete not working” or “PushGateway groups delete not working”. First of all, you must specify all the keys of the group that you want to delete.You need to delete groups with such […]
READ MORELet’s imagine that you need to download a certificate from a website / service / endpoint and put it in the trusted certificates store (JKS or cacerts). To do this, you need to fill in the parameters SERVER_URL, ALIAS_NAME, CERT_NAME and run the script: As a result, an trusted jks storage will be created with […]
READ MOREFull error text: This error can be encountered if there are signed libraries among the dependencies of your project. To solve the problem, you need to exclude files with the extensions .SF, .DSA, .RSA from the build. Of course, we will assume that you are building uber jar (fat jar). For Maven: For Gradle: Complete […]
READ MOREYou can get this error if you try to run jar without specifying the name of the class that contains fun main() and which you want to run. To do this, you need to register the full class name in the Main-Class key of your manifest. Plain jar without dependencies You need to replace the […]
READ MOREIn this article, we will find a solution to the question – how to make an uber jar Gradle Kotlin DSL or how to make a fat jar Gradle Kotlin DSL. Let’s add this to build.gradle.kts file: After that, you can build the jar with dependencies: That’s all. Possible errors Error: no main manifest attribute, […]
READ MOREIn this article we will find the answer for questions: How to change the column in Spark? How to modify column in Spark? In other words: how to create a user defined function (UDF) and apply it. For example, let’s have a look to UDF, that takes a String and returns a String. For Spark […]
READ MOREThe problem You may encounter errors like this when running a Spark script / application: Solutions If you do not need the MetaStore server, there are two ways to disable it. Please note that Spark version >= 2.x is required. The first way (via spark2-submit parameters) The second way (via SparkConf object) Java example: Scala […]
READ MOREIf you need to make your own implementation of OutputCommiter for spark parquet-output tasks, then first of all you need to make a class that extends from org.apache.hadoop.mapreduce.OutputCommiter: Further, regardless of implementation of the OutputCommiter, you need to register the full class name in the Hadoop (!) configuration of Spark like this: Example for Scala: […]
READ MOREThe problem Sometimes you need to run such a scenario when several Spark tasks write data along the same path to HDFS. During the execution of tasks, you may encounter some errors: Suppose we have one Spark task, that writes to the hdfs://data/test directory. At runtime, Spark will make a temporary directory: hdfs://data/test/_temporary/0. There is […]
READ MORELet’s suppose that you need configure a TCP server in Spring / Spring Boot application. We will make it that the server prints the client’s request on the screen, then sends a response to the client. First, let’s include the spring-integration-ip dependency. In Maven it will look like this: Like gRPC ideology, in this case […]
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