Documentation
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Overview ¶
Package pluginsocket connects a server to its plugin sidecar over a Unix socket. It depends on no plugin implementation, so a server that only calls a plugin does not link the plugin's storage SDKs.
Index ¶
Constants ¶
const ReadyWait = 30 * time.Second
ReadyWait is the ready wait servers pass to Dial. It rides through a sidecar restart, including the first 10s step of kubelet's crash-loop back-off, and fails a plugin that stays down well before a caller's deadline would.
Variables ¶
This section is empty.
Functions ¶
func CallError ¶
CallError returns the error a server reports to its own caller for a failed plugin call. codes.Unavailable, which a call reports when the plugin cannot be reached, becomes an apierror.Unavailable so the server's caller retries rather than treating it as Internal. Any other error is returned unchanged.
func Dial ¶
Dial returns a long-lived client connection to a plugin socket. A unary call waits up to readyWait for the connection to become ready, then fails with codes.Unavailable, so a plugin that is lost after startup fails calls promptly while a brief restart does not. A call that starts on a ready connection is not bounded by readyWait, and one in flight when the plugin goes fails with codes.Unavailable at once. A caller that passes grpc.WaitForReady itself opts out of the bound and waits as long as its context allows; WaitReady does so at startup.
The bound covers unary calls only. A streaming call gets gRPC's plain fail-fast and fails at once while the plugin restarts, so the first streaming RPC on this connection needs a grpc.WithStreamInterceptor that applies the same wait.
The connection is unauthenticated: the socket is reachable only from inside the pod, and only by its owner.
func Listen ¶
Listen removes any stale socket at path and listens on a fresh one that only the socket's owner can connect to.
func WaitReady ¶
func WaitReady(ctx context.Context, conn *grpc.ClientConn) error
WaitReady blocks until the plugin behind conn reports that it is serving, or ctx ends, however long the plugin takes to come up. Bounding ctx is what turns a plugin that never comes up (a wrong socket path, a crash loop) into an error at startup.
Types ¶
This section is empty.
Source Files