It's something we debated in our team: if there's an API that returns data based on filters, what's the better behavior if no filters are provided - return everything or return nothing?
The consensus was that returning everything is rarely what's desired, for two reasons: first, if the system grows, allowing API users to return everything at once can be a problem both for our server (lots of data in RAM when fetching from the DB => OOM, and additional stress on the DB) and for the user (the same problem on their side). Second, it's easy to forget to specify filters, especially in cases like "let's delete something based on some filters."
So the standard practice now is to return nothing if no filters are provided, and we pay attention to it during code reviews. If the user does really want all the data, you can add pagination to your API. With pagination, it's very unlikely for the user to accidentally fetch everything because they must explicitly work with pagination tokens, etc.
Another option, if you don't want pagination, is to have a separate method named accordingly, like ListAllObjects, without any filters.
The consensus was that returning everything is rarely what's desired, for two reasons: first, if the system grows, allowing API users to return everything at once can be a problem both for our server (lots of data in RAM when fetching from the DB => OOM, and additional stress on the DB) and for the user (the same problem on their side). Second, it's easy to forget to specify filters, especially in cases like "let's delete something based on some filters."
So the standard practice now is to return nothing if no filters are provided, and we pay attention to it during code reviews. If the user does really want all the data, you can add pagination to your API. With pagination, it's very unlikely for the user to accidentally fetch everything because they must explicitly work with pagination tokens, etc.
Another option, if you don't want pagination, is to have a separate method named accordingly, like ListAllObjects, without any filters.