If I want to check for a specific (nested) object value, I can do this by
if (configuration?.my_project?.frontend?.version)
instead of
if (
configuration &&
configuration.my_project &&
configuration.my_project.frontend &&
configuration.my_project.frontend.version
)
But how do I handle this if I want to do this for dynamic keys using variables?
configuration[project][app].version
would fail for { my_project: {} } as there is no frontend.
So if I want to check if version is missing for a specific app in a specific project, I'm going this way:
if (
configuration &&
configuration[project] &&
configuration[project][app] &&
!configuration[project][app].version
)
The only part I see is just !configuration[project][app]?.version, but this would also fail for { my_project: {} }
Use:
configuration?.[project]?.[app]?.version
But if you want to check specifically that version is missing (i.e. falsey) you'll need to split your tests:
const my_app = configuration?.[project]?.[app];
if (my_app && !my_app.version) {
...
}
You can use optional chaining for the brackets syntax like so:
const configuration = {}
const project = 'someProject'
const app = 'someApp'
console.log(configuration?.[project]?.[app]?.version)
configuration[project] = {}
console.log(configuration?.[project]?.[app]?.version)
configuration[project][app] = {version: '1.0.0'}
console.log(configuration?.[project]?.[app]?.version)More details in the documentation: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/Optional_chaining