1. How to cast pulumi.Output to string in TypeScript?


    In Pulumi, you may want to cast a pulumi.Output<T> value to a string for simple console log purposes or for use within a part of your script where a raw string is needed. However, pulumi.Output<T> values represent a value which will be available in the future, not at the time of execution of your script, hence it requires a special method to deal with this.

    To handle this, we can use the apply method available on instances of pulumi.Output<T>. This method allows you to provide a callback function, which will be invoked with the eventual outputted value.

    Here's an example of how to do it:

    import * as pulumi from "@pulumi/pulumi"; let myOutput: pulumi.Output<string> = /* some pulumi.Output<string> here */ myOutput.apply(value => { // value here is automatically of type string console.log("My value: ", value); return value; });

    In this snippet, value inside the apply function will be of type string and can be used wherever a string is required. However, do remember that this function will be executed asynchronously in the future, not at the time your script is initially processed.

    The type T in pulumi.Output<T> can be any data type such as string, number, custom interface, etc. The apply method can also return a different type, which will change the type of the output. For example:

    let myOutputNumber: pulumi.Output<number> = myOutput.apply(value => { let numberValue = parseInt(value); console.log("My value as number: ", numberValue); return numberValue; // changing the Output type to number });

    Now, myOutputNumber is of type pulumi.Output<number>, not pulumi.Output<string>.