How to handle context of a processing.

I need to sign the content of body, then add to head.
The signKey is different for each different user.
So i need to pass signKey to SignRequestInterceptor, the signKey is context.
there is context concept in WebClient, can be retrive in any part of the procedue.

q1:
In feign, is there any official way to save the context?

q2:
We could use header as the context, but the defaultRequestHeaders is added as interceptor after the requestInterceptors.
so we can't get the head in requestInterceptors.

Can feign fix it, change the order?

        defaultRequestHeaders:
          APP_ID: 123
          APP_KEY: abc
        requestInterceptors:
          - club.AuthRequestInterceptor

FeignClientFactoryBean.configureUsingProperties:

		if (config.getRequestInterceptors() != null && !config.getRequestInterceptors().isEmpty()) {
			// this will add request interceptor to builder, not replace existing
			for (Class<RequestInterceptor> bean : config.getRequestInterceptors()) {
				RequestInterceptor interceptor = getOrInstantiate(bean);
				builder.requestInterceptor(interceptor);
			}
		}
                ....
               /
		addDefaultRequestHeaders(config, builder);

Start with FeignClientFactoryBean.configureUsingProperties and the RequestInterceptor configuration shown in the issue. Trace how defaultRequestHeaders and requestInterceptors are applied, then determine the supported way to propagate per-user signing context and whether their ordering can be changed. Done means the behavior or official guidance answers both questions and is validated against the relevant configuration flow.