Angular's HttpClient Does Not Submit the Request Until Subscribed To

Angular’s HttpClient does not submit requests until it receives a subscription (and in case it receives multiple subscriptions, will submit requests multiple times).

While this is very clear in the HttpClient documentation, whenever I take some time between projects, I usually forget it, especially for POST requests that return No Content and so nothing needs to be done that would require a subscription. You can use void firstValueFrom to simplify the Observable to a Promise at the expense of some features (no canceling the request when the user navigates away, no retry mechanism). await firstValueFrom will get you the data in case of a success, and throw an exception which you can catch (or handle data in finally) on error.