Nushell has very useful commands to filter lists and tables. When you have a list with null values, you can use the compact command to filter out the null values. With the option --empty you can also filter out empty items like empty strings, empty lists and empty records. If you want to filter out rows in a table where a column contains a null value, you can use the compact command followed by the name of the column.

Nushell has some nice built-in commands to get randomized data. The random command can be used to get random numbers, strings, and more. You can use the dice subcommand to get random numbers between 1 and 6. The command returns a list of integers. With the option --dice you can specify how many times to throw the dice. By default the dice has 6 sides, but you can use the option --sides to change that. You could roll a dice with 2 sides, like flipping a coin, or roll a dice with 10 sides.

The nice thing about the http command in Nushell is that you can interact with HTTP endpoints without the need to install any external tools. You can use several subcommands like get, post, put, delete and patch. Each of these commands has the options to specify request headers. You can use the option --headers or the short version -H followed by a list of header keys and values.

The http command in Nushell can be used to interact with HTTP endpoints. You can post data to an endpoint using the post subcommand. If you want to post JSON data than you can simply use a record data structure and use the argument --content-type application/json (or the shorthand -t application/json). Nushell will automatically convert the record data structure to JSON and use it as the body of the HTTP request.

Nushell has a built-in command to invoke HTTP requests: http. You don’t need an external tool like curl or httpie to make HTTP requests. There a lot of options to use with the http command. One of them is the --full or shorter -f option to return a table with extra details of the HTTP request and response. The request and response headers, the body and status are returned in the table. You can easily get information from the table with all the default selection options for a table structure.

Nushell has a lot of commands to work with strings. The str kebab-case command can be used to convert a string to kebab case. Kebab-case is a string that contains only lowercase letters and words are separated by hyphens.

SDKMAN! is as powerful tool to install and manage software development kits (SDKs) and tools, like Java, Groovy, Gradle, Maven, Spring Boot and Quarkus. If you want to see if a new version of a SDK or tool is available, you can use the sdk upgrade command. This command will list all outdated SDKs and tools. The installed version and the latest version are shown for each SDK and tool. To see if a single SDK or tool is outdated, you can use the name of the SDK or tool as argument to the sdk upgrade command.

When you enable the /observe endpoints you can configure them to be served on a different port than the application. By default the endpoints are available on the same port as the application. But you can define an extra named socket with another port number in the configuration of the WebServer instance. And in the configuration of the ObserveFeature instance you can define the socket name that should be used for the observe endpoints.

In a previous post you learned how to add information to the /observe/info endpoint. You can also add Git information to the endpoint. For example you can add the Git commit id so you can see check, when the application is running in a production environment, which Git commit for the code was deployed. In order to achieve this you must first generate a properties file with all Git information. The next step is to process this file in your Helidon SE application and add the properties to the /observe/info endpoint.

It is possible to add an endpoint to Helidon SE that can show information about the application. You can add custom information to this endpoint. In order to enable the endpoint you need to add the dependency io.helidon.webserver.observe:helidon-webserver-observe-info to your pom.xml file. This will add the endpoint /observe/info to your application. You can add key-value pairs to your configuration or code that will be exposed in the endpoint.

You can configure a memory health check in Helidon SE. A memory health check will return a status of UP if the memory usage is below a certain threshold percentage and DOWN if the memory usage is above the threshold percentage. The default threshold percentage is 98%. To add the memory health check you need to add the dependency io.helidon.health:helidon-health-checks to your pom.xml file. This dependency contains three health checks: disk space usage, memory usage and dead lock detection.

To configure the memory health check you need to set the configuration property server.features.observe.observers.health.helidon.health.memory.thresholdPercent to the threshold percentage. Alternatively you can set the threshold percentage in your application code.

Suppose you want to return a response based on the Accept header of the request. If the Accept header is application/json you want to return a JSON response and if the Accept header is application/xml you want to return an XML response. You can use the isAccepted(MediaType) of the ServerRequestHeaders class to check if the value of the request header Accept is equal to the specified media type. The method returns true if the media type is defined for the request header Accept and false if not.

In order to convert an object to XML you need to add the dependency com.fasterxml.jackson.dataformat:jackson-dataformat-xml to your pom.xml file: