private void applyOutlierDetection(ClientRequestContext ctx) {
        if (outlierRule == null || !isAcquirable()) {
            return;
        }
        assert outlierDetector != null;
        if (outlierDetector.isOutlier()) {
            return;
        }

        ctx.log().whenComplete().thenAccept(this::detectOutlier);
    }
Tries to complete the {@link #sessionPromise} if the session is ready to serve.

@return {@code true} if the {@link #sessionPromise} has been completed successfully or exceptionally.
        {@code false} if the {@link #sessionPromise} is still incomplete.
core/src/main/java/com/linecorp/armeria/client/HttpSessionHandler.java