Struct ChainedCredentialProvider 

pub struct ChainedCredentialProvider { /* private fields */ }

Try a sequence of CredentialProviders in order, returning the first one that resolves successfully. A provider that returns AuthError::Missing (the configured “not my source” signal) is skipped; any other Error short-circuits and is returned to the caller — failed-but-real credential sources must surface their failure rather than silently fall through.

Typical layout: try environment first, fall back to vault, fall back to instance metadata. The chain is built once at transport-construction time; resolve is hot-path safe.

Implementations

impl ChainedCredentialProvider

pub const fn new(providers: Vec<Arc<dyn CredentialProvider>>) -> Self

Build a chain from the supplied provider list. An empty list is permitted but pointless — every resolve call returns AuthError::Missing.

pub fn len(&self) -> usize

Number of providers in the chain.

pub fn is_empty(&self) -> bool

True when no providers are registered.

Trait Implementations

impl CredentialProvider for ChainedCredentialProvider

fn resolve<'life0, 'async_trait>( &'life0 self, ) -> Pin<Box<dyn Future<Output = Result<Credentials>> + Send + 'async_trait>>

where Self: 'async_trait, 'life0: 'async_trait,

Resolve current credentials. Long-running impls should respect tokio cancellation in their internals; the transport supplies the ExecutionContext indirectly via the surrounding async task.