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require_valid_identifier

microvms_core::control

Function require_valid_identifier 

Source 
pub fn require_valid_identifier(
    member: &str,
    identifier: &str,
) -> Result<(), Error>
Expand description

Rejects a MicrovmIdentifier/MicrovmImageIdentifier the service would reject.

§Twelve members across every implemented operation

Both shapes are min: 1, max: 256, and between them they bound the identifier on GetMicrovm, SuspendMicrovm, ResumeMicrovm, TerminateMicrovm, CreateMicrovmAuthToken, GetMicrovmImage, DeleteMicrovmImage, DeleteMicrovmImageVersion, GetMicrovmImageVersion, UpdateMicrovmImageVersion, GetMicrovmImageBuild, the three listings, and RunMicrovm.imageIdentifier. Issue #24 counted six implemented operations for each shape; every one of them is guarded here.

§An empty identifier is the case that pays for this

Ten of those members are URI parameters, and an empty one does not produce a validation error about a blank field: it collapses the path. GET /2025-09-09/microvms/ addresses the listing, not a VM, so an empty id sent to get_microvm asks a different question and can get a 200 back for it — and DELETE on a collapsed path is worse. That failure mode is invisible in the service’s answer, which is the strongest argument for a local refusal anywhere in this module.

§The model contradicts itself, and this is the side that can be guarded

MicrovmImageArn permits 2048 and is what the service answers with, so the model allows a legal response value that is an illegal request value — see crate::constants::MAX_IDENTIFIER_LEN for the whole account. The message says so, because a caller who hit it by echoing an ARN back is looking at a service inconsistency rather than at their own mistake, and telling them “shorten it” would be useless advice about a value they did not choose.